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Michael Green
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PostSubject: Re: Bill333's System   Mon Mar 14, 2011 7:16 pm

My suggestion would be to keep learning what things do instead of trying to do too much at once. When you find the balancing act that works for you consistently life becomes a lot easier. I'm pretty sure that I could walk into your room right now and make it sound like I wanted is short order but that is because I know how things are relating to each other. I would know when I hear blockage what it was and what to do. I would hear where things were not producing the proper transfers because of knowing what they sound like. Remember that when I do things in front of you I'm hurrying because of time constraints, in the real world I go much slower and more methodical letting things blend into each other rather than taking huge jumps of change. Without knowing the effects of what things do it is easy to get lost and to be honest your room is getting to the place where it is going to start playing itself. If your voice sounds good in your room than your music should sound equally as good. If the system doesn't that means that the equipment side of things is not doing the job and you are trying to force the room to make up for lacks in the system. This is a never ending chase if you don't find the balance between all the different parts.

I think for you the equipment platform is the only way to go. The rack leaning is cramping your style big time. I can relate to this and personally enjoy using a platform canopy setup over the rack type of setup.

Top tuning will save the day once you start understanding it. If your not hearing huge changes by just barely touching the top of what you are tuning than you are doing something very wrong. In both cases when you and I were together here and at your place the single biggest change was when I top tuned your DVD player. There is absolutely no comparison between gravity transfer and top tuning. This is something we will have to get down.

What I see from a distance is that you are trying to make changes using the acoustics that need to be done by top tuning. When these two worlds start complimenting each other you will get where your wanting to go much easier.

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PostSubject: Re: Bill333's System   Mon Mar 14, 2011 9:42 pm

Hi Everyone,

Michael is exactly right about what I was hearing during the above listening session. It was the rack the whole time. I think the slivers of magic wood under the top shelf bolts was deadening the sound. It seemed to work nicely for a few days or a week, then turned bad on me. The thing about it was that all the bolts seemed nicely adjusted, but the sound just wasn't good.

I am hoping to get a nice equipment platform for Christmas. I am also hoping that Christmas comes in April. lol!

To bring everyone up to date, I had Drewster and Scott over for dinner last Saturday night. Having pulled the magic wood off the rack and fiddled with it for a while, the system was actually sounding quite good by Saturday evening. We had a nice time listening to music until Drewster and I decided to do some tuning on the components. To make a long story short, the Altmann DAC was damaged by some kind of electrical discharge from the PaceCar. I have already shipped it off to Germany to be repaired and am currently listening to the DVD player. It pays to have an equipment closet.

Michael's post got me thinking about how my voice sounds in the room now, so I went down and did a quick voice test. My voice sounds a lot more resonant with much more harmonics than I remember it being when the room was first put up. We are still not in 'voice of God' territory yet, but it's clear that the room is maturing.

Another thing going on is that I have all the parts for my Audio PC project. I'll start a separate thread for this on the computer audio forum, but basically I'm trying to build a computer as a music server that can host a digitized music collection and act as S/PDIF transport for a DAC. I'm hoping to answer Michael's concerns about computer-based audio with this project, so we'll see how it turns out.
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PostSubject: Re: Bill333's System   Mon Mar 14, 2011 11:40 pm

This is exciting!

A computer based system that performs at the ultimate level. This would solve so many fears as listeners head into the future with our audiophile "next step".

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PostSubject: Re: Bill333's System   Wed Mar 16, 2011 8:05 am


Hi Bill333

Sonic seconds your observation -- I have tried MW slivers under the bolts of my rack several times. Each time, the immediate effect was good but headed south after a few days. So I have stopped using the slices.

I'm getting used to a livelier room with the plastic sheets and adjusting them for best effect without ringing.

Not nice what happened to the Altmann. Tell me, what did you use to top tune it? What was that long thin rod?

Also I had a good read of Michael's comments about speakers that cannot do mono right. While I agree with him that things like inefficient and overdamped speakers not being able to sing mono, I am not so certain about planars.

For sure, a planar with the tweeter off to one side won't mono well (like Magneplanars) but I would expect the original Quads to do well. This is because they were designed as a mono replay unit first then doubled up when stereo came along. Even in the mono days, the Quads (now referred to as the ELS 57) set the pace for transparency and accuracy at the BBC. Comments as a Quad user?

Oh yes, and Michael is right that throwing a mono switch doesn't work -- double mono is awful. There are networks that can sum two channels nicely like one DIY tube thing I found, using 845 DHT Single-ended triodes. The right way is to use a mono source or sum your stereo properly and use one loudspeaker. That works well as Sonic discovered.

Sonic
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PostSubject: Re: Bill333's System   Wed Mar 16, 2011 11:25 am

Hi Sonic,

Here's the picture of the RoomLens setup that you asked for earlier:



As far as the Altmann DAC goes, I tried several times to top tune it without success. It always seemed to make the sound worse in some way. Usually it wasn't subtle at all. I'm not certain what was going wrong, but I suspect that the wood used for the canopy may not have been up to the task. Michael did a quick sanding and coating on it while he was here, but I don't think it was nearly as dried out or as well cured as he would have liked. That same piece of wood seemed to do the DVD player a lot of good, but the DAC may be more particular about what it needs for a successful top tune.

I had it off its board and put the pcb on magic wood slices for a while also, but it never really sounded better than it did on its board. As you can see from the picture above, I just have it on springs on the rack shelf. I'm sure it's possible to tune it better than that, but I'll leave that to Michael. Eventually I will be sending the entire equipment stack off to him to be custom tuned.

As far as the Quads go, they certainly do have the transparency and accuracy. I can't speak to whether they reproduce the sense of space Michael was talking about, since I've never tried a mono setup. My complaint with them in the past had been that I couldn't get them to image well, but that concern is a thing of the past in the tunable room. Those things soundstage like nobody's business if the equipment and vibrational context (tuning) upstream are right. My only real issue with them now is that the frequency response isn't as flat as I would like. And as good as the Quads are, I suspect that the ultralight cabinets and paper drivers of a highly tuned pair of 60s may may still win out in the end. We'll see.

At the moment, my system is unlistenable. I have the DVD player hooked back up and am running it straight into the RWA amp. I don't know what's going wrong- maybe the rack, or possibly the top tuning on the DVD? I'll post again when I've done some experimenting.

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PostSubject: Re: Bill333's System   Thu Mar 17, 2011 8:24 am


Hi Biull333

Unlistenable sounds very bad. Sonic has had bad moments with the system but so far I always managed to recover because my system has less degrees of freedom so tracking a fault is easier.

The steps I take to do fault tracing goes like this:

a. Check the Tune record and look at what tweaks were most recently done. The problem usually lies one or two tunes back, at most three that have settled and are probably not working with something else that was done.

the max-3 tune back point is where my system restore point will be and work again from there.

b. Alternatively or at the same time, Sonic starts retuning from the beginning of the signal chain. I look at the sources first -- sometimes it is a weak laser or a dirty one in the CD player...it could be a cartridge whose alignment has run. I work forward thru the system to the loudspeakers. If your mains have been tuned then have a look at that too. I once traced a patch of bad sound to a mains wire that was too loose. The Tune thing of keeping things loose has a downside that we always need to be making sure that they don't go too loose. Speaker cable tightness/looseness is something that varies given the vibrations at the wire/jack interface.

Once the gear is balanced, rack balanced and everything tightened to just so, then time to look at the room. Your room is so advanced so there not much I can tell you but I guess checking and varying tightness of things is part of the drill. For my set up, I find the room/acoustic stuff is stable, it is usually the equipment chain that goes off (unless I start tuning and getting it wrong like i did recently).

Sonic will try not to jump from the equipment-tune path to room path and back again when debugging a system. I know they are interrelated but I have gotten confused and worsen things.

Thanks for the pix. Hope you get out of this rut soon.

Sonic
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PostSubject: Re: Bill333's System   Thu Mar 17, 2011 6:13 pm

Hi Sonic & Bill333

I think this is a very nice list. It's good that we get to our own method of how we are going to go about shaping the tune of things. For myself I find it much easier to do all of the variables as if they were one. That is probably because I have found the link between all of them and treat them as one. Tuning for me (once I learn the system) is more of a slide than a jump. I only jump if I know I have time constraints (like a show or quick client visit). Where as Sonic takes notes (which I think is a great idea) I make judgements based on when I hear the energy shifting from one part of the trilogy to the next. It works like this. Find the weakest link then make it the strongest. This will then show you the new weakest. I keep volleying these until the whole system is raised to a much higher level.

In a post I recently did I started jumping on the audiophiles for not getting it based on what I was seeing on another forum. It blows my mind how we can start adding parts before learning the greatness of simplicity. For my own listening things are much easier when I use the fewest possible pieces and parts. I think this is because I have been able to achieve 2 things relatively well. One, I am so used to listening to materials that they jump out at me while listening like someone is screaming in my ear "I don't fit" or whispering "now that feels good". I don't know why that is, it just is an easy thing for me. An example is when I hear you guys talk about using slivers of Magic Wood. For me it is so easy to hear the transfer that I will ad or subtract an amount or pressure till I get it right. To you guys it seems like you are treating it much more like a jump of good or bad instead of using the pieces like a varying slide tool interchanged with other wood or materials to flavour or set free. I might be over stating this but I just want to make the point of the varying process vs all or nothing. Number two is technology itself. I read recording journals from time to time as well as audio industry ones to not only learn a little but to build up the fact that movement is a part of every thing.

Here's a simple example (I'm not saying right or wrong here, I'm just giving a well documented example from a few years ago). I left out the diagrams cause you guys have seen them tons of times before.
________________________________________

Vast amounts of marketing efforts are placed on touting the latest and greatest technological advancements in the realm of home audio. We are all aware of the over-inflated, and often baseless claims that companies tend to make when advertising their new products. The latest A/V receiver and A/V Processor offerings are currently marketing super high sampling rates and wide bit words for processing digital audio signals. The ability to upsample to these extreme rates is a main advertising point for many A/V receivers. So does upsampling to higher rates really provide better sound? The following will briefly try to go into the details behind why upsampling is used and if it really is the answer to better sound.

Basics of Sampling - Oversampling and Upsampling

To start with, we must review the system as a whole and look at the terminology. Two main parts of the whole system we are going to consider are upsampling and oversampling. In the purely mathematical context, they are similar operations. When practically implemented though, oversampling refers to using a higher sampling rate than needed to run the A/D or D/A converter thus increasing the rate of the signal. Upsampling is on the other hand a rate conversion from one rate to another arbitrary rate. Oversampling in the ADC has been around for quite a bit of time, while upsampling of audio that results in a simple rate conversion is relatively newer. The figure below shows an example of oversampling. We assume that we can sufficiently sample the analog waveform at twice the bandwidth of the signal as to prevent any aliasing in each case. In one case we are sampling at some frequency, f s and in the other case we are at twice the same sampling rate. The resulting data samples are shown to the right in the figure. In both cases we have assumed that we are at twice the Nyquist rate for the signal to prevent any aliasing.



Figure 1 : Oversampling Operation


A rate conversion in the middle of the digital processing, or upsampling, looks slightly different depending on how it is specifically implemented. The simplest of these implementations entails zero stuffing the original sample stream to increase the sample rate. Other implementations may create the additional samples by taking some weighted averaging of the samples in the original rate. In almost all cases, the upsampling process also includes an interpolation filter to get rid of the images of the original signal.

A simple block diagram of a processing chain is shown below. The Analysis filter sits prior to the ADC and isolates our signal of interest before we sample it. Oversampling is performed at the ADC and then the signal is sent to the digital processing chain that does the filtering and any DSP operations. The upsampler (if any) sits somewhere between the DSP and filtering. Just like the ADC, the DAC also oversamples the signal. Oversampling at the DAC and ADC will make the design of all our filters much simpler as we will see.



Figure 2 : Basic Signal Processing Chain


Effects on Frequency Response

To get a better idea of what is going on with our original signal when we upsample or oversample, we need to look at it in the frequency domain. That will allow us to see what benefits we gain by going to a higher sample rate. The figure below shows the result of taking our standard audio spectrum that ranges from 20Hz to 20kHz and then increasing its rate by 8x.




Figure 3 : Oversampling/Upsampling Effects on Frequency


Whether we upsample or oversample, the effect on the spectrum of our audio signal is similar. Instead of our signal of interest occupying almost our entire bandwidth all the way up to fs/2 (22.05 kHz), it now only occupies 1/8 th of that. This allows us the use of a very simple analysis filter at the head of our processing chain, the internal digital filters, or the reconstruction filter at the end of the chain. Both the processes of upsampling and oversampling give us this benefit. Without increasing the sample rate, we would need to design a very sharp filter that would have to cutoff at just past 20kHz and be 80-100dB down at 22kHz. Such a filter is not only very difficult and expensive to implement, but may sacrifice some of the audible spectrum in its rolloff. If we examine the spectrum at the increased rate, we can see that the filter can roll off gently well past 22kHz and as long as it is down in the cutoff region at 176.4kHz, the image created by the sampling process will easily be removed. The analog filter after the D/A converter is responsible for removing the audio signal's image as well as the frequency spurs caused by the DACs integration steps. An analog filter with a smooth roll off will have nicer phase characteristics as well.

To demonstrate these benefits, let's take a look at two analog filters: one that must operate at Nyquist, and one that can operate at 64x Nyquist. The filter that operates at Nyquist, must have a very sharp cutoff and a higher order. The figure below shows a 10 th order Bessel lowpass filter. We can see that the filter rolloff is very sharp and the corresponding phase response is nonlinear towards the higher frequencies. Such variations in phase are undesirable in our audio signal. The plots below are a function of radians rather than hertz and are in logarithmic scale. On the radians scale, our audio signal occupies 125.66 rad/s up to 138544 rad/s, which roughly corresponds to 10^2 and 10^5 on the plots.




Figure 4 : Analog Filter at Nyquist


Now lets look at a filter that operates on our bandlimited audio signal at 64x Nyquist. This filter is a 3 rd order Bessel lowpass filter that cuts off well after our audio spectrum. The rolloff is much gentler, but the phase response is notably better. It is linear over almost the entire audio spectrum, which extends from 0 rad/s up to 138544 rad/s.




Figure 5 : Analog Filter at 64x Nyquist


The phase response of the analog reconstruction filter after the DAC is a function of the type of filter used and how much oversampling the DAC uses. A higher oversampling will allow for a more linear phase response over the audio spectrum for a given analog filter structure. The DACs oversampling to a higher rate allows for a reasonable analog filter design that gives us linear phase. The key point is that the oversampling in the DAC and the oversampling in the ADC are both important parts of the processing that have been used for a very long time.

Upsampling would give us the same benefits in frequency response that we have gone over, however we can achieve the same effects by sufficiently oversampling our signal both at the DAC and ADC. Upsampling has no effect on our digital filter design problem since all our digital filters are FIR (finite impulse response) and all have linear phase. By sufficiently oversampling at the ADC, we can design a very simple, linear phase, digital filter that has no problems with our audio signal. There has been much misinformation surrounding upsampling and many claims have been made that state that upsampling is necessary to allow for such a desirable digital filter. However, it is the oversampling at the ADC takes care of this, not upsampling. To demonstrate, lets take our audio signal that has been oversampled at 8x Nyquist and design a digital filter for it.

Below we have a symmetric digital FIR filter. The plot below is in normalized frequency where 1 = 176.4kHz. Our audio signal extends from approximately .00011338 up to .125. From this we can see that the passband of our filter is smooth over this frequency range and that the phase response is linear. At just past 22kHz, the response of the filter is down only 6 db and falls off to below -120dB soon after.

Jitter
Jitter is basically a timing error that is caused by inaccuracies of a system clock relative to the data stream. In an ADC for example, jitter will cause the sampling of the analog waveform either too early or too late relative to the previous sample. This error will cause the sample's level to be incorrect. Logically, a signal that is high frequency and high amplitude will be more likely to be affected by jitter than one that is lower frequency and smaller amplitude. One major claim that the proponents of upsampling, or sample rate conversion claim is reduction of the effects of this jitter. It is very important to note that the increase in rate itself is not responsible for the reduction in jitter. In fact, the jitter that is caused by the inaccurate ADC clock can not be removed completely since it is already present in our digital samples. However by upsampling to another rate and using a clock that is asynchronous to our original, the incorrectly sampled data can be somewhat corrected. Basically what we achieve is a 'spreading out' of the effects caused by sampling jitter over a wider spectrum. Jitter appears in our system by increasing the noise floor on our audio spectrum. By going through this rate increase, we basically spread out this jitter over more samples, interpolate, and then filter once again. One popular ASIC that does such a function is the AD1896 produced by Analog Devices. Another important point to note is that if not implemented correctly, this whole process of upsampling can actually yield poorer results. Also, with the use of an accurate clock relative to our input data's frequency, we can greatly reduce the effects of jitter at the head end. The amount of jitter that is really audible is something that is debated religiously and the psychoacoustics behind that is beyond the scope of this.

Oversampling DACs and Bits
Oversampling is widely used in the DAC. The effects of oversampling at the DAC are advantageous to the design of the analog reconstruction filter that must be built, as we have seen previously. By having a high sample rate out of our DAC we can use a very simple, gentle analog filter to reconstruct our analog filter. This is important since we will be able to design an analog filter that is not only cheap hardware wise, but also has a nice linear phase response over the passband.

Another reason for oversampling is to reduce the effects of quantization noise. By oversampling, we can spread any quantization noise over a larger bandwidth while keeping our signal of interest in the same band. Our filter will serve to cut out the out-of-band quantization noise while keeping our original signal and thereby increasing our SNR. For each factor of four that we oversample by, we gain 6dB of noise lowering. 6dB represents approximately one bit of information. By oversampling, we can theoretically drop one bit for every 4x increase in sample rate.

The question of number of bits is another thing to consider. Does carrying extra bits increase the amount of information in our signal? Unfortunately, once we have sampled our signal, nothing can be done to increase the amount of information we have to work with. What carrying more bits does is that it prevents the loss of information. DSP algorithms and filters require additions, multiplications, and other math functions. If we are able to carry more bits in the results of these operations, we lose less information by chopping off fewer bits. Every truncation of a result will add noise to our signal. But now we can see that by balancing the number of bits we carry in our computations and by the amount we oversample, we can reduce the effect of this truncation in word length. One thing to note is that many products claim 24-bit word lengths, but yet only process internally at 20 bits.

What Does This All Mean - Will it Sound Better?
So the question remains whether upsampling or oversampling actually make music sound 'better'. How much do we need? We have seen the main motivation behind oversampling and how it allows us to use simpler digital and analog filters as well as helping us with quantization noise. The effects of upsampling are greatly debated. While it is true that upsampling does help us in attenuating the amount of jitter caused by sampling errors and an inaccurate clock, whether this jitter is audible or not is a point of contention. There is no doubt that wide bit words and super-high sampling rates that are touted by the latest products are largely marketing. Oversampling has been around for a very long time and has been used extensively in audio products to not only improve sound quality through 'better' filtering but to make these same products much cheaper. Upsampling, on the other hand, is relatively newer and debated greatly. The effects of upsampling are no doubt overstated. By carefully designing the sampler, ADC, digital processing path, and oversampling DAC, the upsampling and asynchronous rate transfer can, in my opinion, be avoided.

The Purists Point of View
There are basically two points of view regarding this upsampling an oversampling. The audio 'purists' want no additional processing on their signal and want whatever comes in from the source to come out as analog. They talk about zero oversampling DACs and such that are completely filter free both in the analog and digital domain. That is one extreme that some may argue is the purest since it avoids any digital artifacts and it's quality relies on human perception by arguing that the human ear in itself acts as a brickwall filter after 20 kHz. Whenever we get into debates of human perception, the math and theory go out the window. Does it sound better without all the digital processing and filtering even with the image of the signal sitting just past fs/2? The energy past 22.05kHz is still present and you are still sending it to the speaker's tweeter. How will the tweeter react to such out-of-band frequencies that are present? Furthermore, sending such a signal that is not limited in bandwidth could cause stability problems with wide-bandwidth amplifiers that have a high unity-gain crossing. The overall system's signal-to-noise- ratio will be adversely affected as well. The DAC will also introduce frequency spurs all over the place. If we don't filter them at all, what will their presence do to the sound? It's a complicated problem and such a minimalist approach could introduce more non-linearities and negative effects, more so than the digital processing ever would.
_______________________________

We have all read hundreds of these right? Some more technical than others. Some we agree with more than others. These are published in both pro journals and home audio mags.

I have no idea what you guys look at when you read these but what I see is movement. Whether it be DAC or ADC there is movement and that means correction needs to be made to a moving signal. The question is, in my world is it better to correct a simple signal like the one produced in the Mag 100 or the more difficult signal that is produced by using additional components? At this point I give the advantage to the simple component with fewer parts and less over all weight and path jumps. I don't base my opinions on something that I haven't heard at a basic level but it must be inside of the fully tuned system atmosphere.

Now, there is a difference from what I'm hearing now and what I will be doing in the future with Bill333s setups. With what I know in the performance of the Mag 100 I know where I can go and how much I can make the tuning of this unit do harmonically to reproduce the extremes of listening. The future will be, will I be able to go further with the new more complicated system. We will see cause they will be going head to head. And when I say head to head this is not a personal taste thing but a how far can the boundaries get stretched thing.

As we will be exploring the computer based system you will see how my aim is at making a great, better, best stepping progression. I'm hoping that I will be able to say that we have stepped beyond the Mag type of sound which to the present day I can not say this with confidence.

If you guys hear me sounding a little critical as this is happening please try to keep this in context of what I am doing and not in the context of Bill333 or sonics personal taste. How someone dials in their own sound is up to them. It's an area that I don't really need to have much say in cause that is someones personal fun space.

So as we go through the next few months things should get pretty exciting I hope and maybe we will actually come up with some pretty cool answers to share along with personal taste comments.



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PostSubject: Re: Bill333's System   Fri Mar 18, 2011 1:27 am

Boy, there's a lot to chew on here. The Magnavox DVD player and the Altmann DAC are as different as two pieces of electronics can be.

In one corner we have a device whose entry into the world of high fidelity audio is completely unintentional: created by a mass market manufacturer to play DVDs, not CDs, it has had size, materials and parts whittled off of it in a relentless drive to bring its retail price to a bare minimum. It's a safe bet that the engineers who created the MDV100 spent most of their time on DVD-related functionality, not much time evaluating picture quality, and none at all listening to the player as a high fidelity audio source. But those same engineering choices have created a low mass, integrated digital source which can be tuned to extraordinarily high levels.

In the other corner we have the Altmann Attraction DAC: designed and handbuilt by a single individual working out of his home, its development was driven by Charles Altmann's desire to create the most sonically satisfying, unfatigueing and beautiful sounding digital music source in the world. Rejecting upsampling, oversampling and current DAC designs as unnatural sounding, he uses only ladder DACs which directly convert digital information into voltage. In an effort to increase fidelity, the DAC is powered by a battery and intentionally kept separate from the transport. In addition, the parts have been kept to a bare minimum and the signal path kept as short as possible on a single printed circuit board. The result? A low mass, non-integrated digital source which should be able to be tuned to extraordinarily high levels.

But should be is not the same thing as is, and good intentions do not necessarily make good sound. In fact, it would be fair to say that high end audio is littered with products whose high fidelity intentions fall well short of the mark, especially in a tuned system. Charles' decision to keep the DAC's circuitry and its power separate from its transport source may increase the purity of the DAC, but at what cost in signal degradation from the extra parts in the transport and the connection between source and DAC?

The end result? I don't know. I think the Altmann DAC has a more natural, more real sound to it that I would be surprised if Michael doesn't hear. On the other hand, perhaps good tuning makes the nature of the conversion process irrelevant and the integrated nature of the DVD player wins out over the separate components and S/PDIF conversions of the DAC.

But I would like to make just one more point. It's interesting that Michael chose the above article about upsampling and oversampling, because in those terms the Altmann actually has a much simpler and more direct signal path than the Magnavox. The current DACs used in mass market devices like the MDV100 are all multibit sigma-delta designs which use heavy oversampling and filtering as an inherent part of the conversion process. So the signal path of the DVD player is not as simple as it may appear to be.


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PostSubject: Re: Bill333's System   Fri Mar 18, 2011 5:13 am

Should be fun!

As far as my taste goes when talking about what is "real" I probably won't get too much into that but more on the fundamentals of the recording reproduction. Flavoring the music I tend to leave to the beholder and find it fascinating to be honest. The first thing I will be looking for will be the harmonic balance that leads to the placement of the staging. When in balance we're able to hear the movements within the recording very easily. I'll be happy to walk through this while it is happening in case anyone wants to follow along on their system. I did this a little bit at Bill's place when listening to Abbey Road (all we had time for). It's a wonderful and easy recording to follow. The engineering is full of movement and many classes have been given on these movements and meanings so that makes it even more fun for me. It's always fun to once or twice a year to put myself through the staging game. I find so many cool things inside the recordings that remind me of why I like them so well. As I've said many times once you learned how to unlock the door it goes beyond what is and moves to where do you want to go. The where do you want to go is great and I go there often but the fundamental is where I start when I'm evaluating. That will be where I will put the parts and pieces to the test.

Tonal balance will also be an easy one because here again if a system is out of balance it will have a tendency to group around certain areas of the soundstage and gather on a set of frequencies. I tend to let the space dictate the tonality cause not being there while recorded the artist and engineer may and always do have their own twist on things. It's more fun for me to listen to them do their thing instead of me changing it. At the same time I do like to play my games after the balance and staging is in place and again anyone can follow along to see if they can do this with their system.

There are always "did you hear this" in recordings so it will be nice to hear you guys send me after a few cues as well. I love learning different parts to the recording I haven't heard before.

As far as the article it was just a random choice but I do hope that we go much further than the Mag 100. It would be interesting indeed to know that the audiophile version of high end audio could not beat up on a $29 DVD player that was not built for audio. That's sad or maybe not.

sunny

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PostSubject: Re: Bill333's System   Sat Mar 19, 2011 4:53 pm

Hey, Bill333,

Here's a bit of advice for ALL of us to keep in mind from Jim Bookhard in The Archives:

My intention of my post was to make clear to everyone, as well as reassuring them, that losing the sonic envelope happens to everyone, even Michael. The only difference with it happening to Michael is that he may do it deliberately because he momentarily is going after something else and then he will bring the sonic envelope back.

All of us should keep in mind that the changes we make to our tunable systems have dramatic effects on what is finally heard through our ears. There is no shame in losing the envelope and, as I said, learning to tune is a process which takes time and understanding. And, while I'm at it, yes, your racks are and should be the components with the highest level of tuning in your system.


He also mentioned something that I find kind of personally daunting which was that when you change one thing, you may have to go through the whole system again, the "everything affects everything" principle.
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PostSubject: Re: Bill333's System   Mon Mar 21, 2011 11:12 am

Hi there Bill333

Sonic has been reading up on the wonderful Quad you use. Great speaker, perhaps one of the greatest ever. I noticed you are placing them low to the ground -- can't see exactly but you have them on the three little wooden feet, no?

Here's something I learnt -- if you place your Quads this way, that is the correct thing to do. Some audiophiles use various stands to raise the Quads to ear level -- there are different stands out there to do this -- and the users then report a startling increase in clarity and focus.

Sonic read that raising the Quad ELS 57 and the later ELS 63 causes a mid bass cancellation notch around 200 to 300 hz that is very deep (like -10 to -20 dB, I read, which is very audible). This cancellation is the function of the different path lengths from the direct sound reaching your ears and a first reflection bounce off the floor at a point between you and speaker. This creates a cancellation which makes the musick go thin and lean and depending on the room environment, personal preferences and equipment interface, is interpreted as "stunning clarity". Apparently, the later Quad ESL 63 was meant to be placed directly on the floor! The late Peter Walker had his own 63s placed this way in his own home (from the "Quad -- The Closest Approach" coffee table book.

Sonic

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PostSubject: Re: Bill333's System   Mon Mar 21, 2011 11:56 am

Hi Sonic,

Yes, they're on the ground on their little wooden feet. Well, actually there are some finished out pieces of 2x4 between the feet and the floor of the room to improve the vibrational quality until the Quad platforms get here. But yes, they sit pretty low.

As far as cancellation points and bass suckouts go, I really don't think you can apply that kind of analysis to a nearfield room setup. The speakers excite the entire room at once which is a very different situation from what those people were measuring way back when. In addition, the standard nearfield setup has the direct wave of the speakers going past the listening position (in my room the Quads are actually toed outward slightly) so whatever clarity is heard is not so much a function of height or angle, as it is that particular position's ability to energize the pressure zones properly.

To be honest, even when I had stands that lifted the Quads up, I never really heard the bass suckout people talk about. What I do hear with my current setup in the tunable room, is that the soundstage is lower on the sides than it is in the center. Images tend to be about 5-6 feet high in the center and then gradually go down to about 3 feet at the far left and right of the soundstage. If I was to go down the road of improving the Quads, that would pretty certainly include building a pair of stands for them that would bring them up to ear level and eliminate the back tilt and the curvature of the panels. Any frequency response anomalies would be worked out with the wood in the speakers as much as possible, and then with the room.
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PostSubject: Re: Bill333's System   Tue Mar 22, 2011 11:27 am


Hi Bill333

Congratulations! Quads toed out and still giving useful treble is uncanny. Shows what the Tune can do to turn audiophile assumptions upsidedown.

How's the rack and your room/wall settings coming along?

Sonic
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Michael Green
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PostSubject: Re: Bill333's System   Sat Apr 02, 2011 11:52 am

Yes,

The Tunable Room is designed not to defy the laws of room acoustics but to let room acoustics be what they want to be naturally. When true acoustics happen the audiophile laws of physics goes right out the window. In fact if you took the Quads and removed any blockage in the design and built them to work with the room conditions like Bill was saying they would completely disappear. The room would take over and they would just be producing sound waves & pressure.

I wish I was at Bill's room every weekend to play. How much fun would that be!

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PostSubject: Re: Bill333's System   Sun Apr 03, 2011 8:58 am

Hi Michael,

I wish you were over every weekend, too. The room and my system could use the attention, and it's always nice to have someone around who knows good food when they see it. I would love to be hearing what you're hearing in Vegas these days. If you've got Clayton glued to the listening seat, I'm sure I would be too. In any case, I'm hoping we can schedule another visit before too long.

Hi Sonic,

The room and my rack have definitely had their ups and downs over the last few weeks. Aside from my last bout of playing with the walls, I really haven't done anything with the room. I set the screws so that nothing was obviously out of whack and just left them there. When I say out of whack, I really mean gross anomalies like ridiculously over-hardened sound. I have no doubt that the room acoustics can be tuned to a much higher level, but that will have to wait until Michael comes again.

The rack is still the same wild card that it has been. Sometimes I can get fairly good sound out of it, sometimes not. A lot of the time I find it difficult to say what contribution to the sound is coming from the rack and what is coming from the equipment and its tuning.

What's most interesting lately is what's been going on with the equipment. I mentioned before that I sent the Attraction DAC to Germany to be repaired, but I also sent the PaceCar away to be modified with a TosLink output. So I really had no source for the system except the DVD player which was not a very happy situation. The Magnavox can sound quite good when it's properly tuned but to do that it really has to be top-tuned. Just putting it up on springs and wood is not enough.

Which brings us to my top tuning canopy. This is the one that Michael mentioned in his thread recently. It was from a set of canopies that I ordered years ago and never used. When Michael was here, he sanded it down and gave it a couple coats of poly and set it up on the DVD player. Back in the beginning it did the DVD player a lot of good, but when I tried to use it on the Altmann DAC I was unable to get an improvement over the sound of the board the DAC came with. With the DAC out of my system again, I got the canopy out and set it up on the DVD player like I had it before. But this time it actually made the sound worse. I tried top tuning the Magnavox a dozen different times (yes, I allowed time for settling), but each time it did something terrible to the sound. Sometimes it had a positive effect as well, but always at an unacceptable cost.

Due to its effect on my system, I have given this canopy its own name: THE BADINATOR. But I should stop telling you about The Badinator and let it speak for itself:

The Badinator (with Teutonic accent): I am The Badinator and I am coming for your system!

Audiophiles: Nooooo!

The Badinator: I will force your soundstage down to the level of your knees!

Audiophiles: Nooooo!

The Badinator: I will improve your clarity and dynamics but at the same time make your sound so crabbed that you can not even understand the vocals!

Audiophiles: Nooooo!

The good news is that The Badinator has been packed up and sent off to Michael, so it won't be terrorizing my system anymore.
Note to Michael: Run!

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PostSubject: Re: Bill333's System   Sun Apr 03, 2011 9:38 am

But there have been some good things going on as well. I decided I needed a second DAC and purchased the DAC WOW! from HotAudio.com. I asked Dave Smith at HotAudio to modify the build of my DAC to make it easier to remove from its chassis, which he was happy to do. The entire DAC is smaller than a pack of cigarettes and has only a single TosLink input and the two line level outputs. Power comes from a lightweight 12V swiching power supply.

I've actually been quite pleased with the sound. It's remarkably clear and dynamic with good soundstaging. Its character seems similar to the DVD player when it's well tuned. So far I haven't done anything with it except put it up on springs, but I expect it will be very tunable. When I get the Altmann DAC back, I will do a thorough comparison and post the results.

The other thing that's new is that my audio PC is finished and working. I have the audio PC feeding the DAC WOW! with an ordinary TosLink cable and am finally enjoying pretty good sound, depending on the disposition of the rack. Here's a picture of the system:



Right now, I am using the mouse, monitor and keyboad, but I'm going to put together a remote system for myself before too long. I don't have the PaceCar on hand for comparison, but the sound I'm getting from the PC seems comparable.
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PostSubject: Re: Bill333's System   Sun Apr 03, 2011 6:00 pm

A side note

I have wood all over the place right now with new cones and spikes set up, the music playing and sand paper scraps piled up to the ceiling. It's been this way for a few weeks as I've been getting my listening groove started in anticipation of computer pieces and parts. Converting a normal room to enter the level of a tunable room is no easy task and demands a ton of concentration to even think it to be close.

OK, here's the side note. I'm in my focus right! Had some errands to do for Andy so I leave the music playing (keeping it fresh in my mind) and I head over to my shipping location office. I'm in there talking to the guys about the things I need for an order (but still in the focus, song playing over in my head). The phone rings and it's Bill333. He tells me about the BADINATOR and that was it, my thoughts became mush as I'm about to bust out laughing. I'm picturing the showdown between Bill and this piece of disobedient wood on top of a rack just waiting to go out of balance again. Now picture this, Bill's sitting in The Tunable Room while this is going down. Life is not fair. There is a sitcom in here somewhere and by golly we're going to produce it.

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PostSubject: Re: Bill333's System   Sat May 07, 2011 8:33 am

There's been a lot going on since I last posted, so I'm going to try to bring people quickly up to date. A couple weeks ago, Michael suggested that I try some Type 2 speaker wire in place of the Type 3 I've been using. This gave the system a much livelier sound which I liked, but also imbalanced the frequency response. My efforts to keep the Type 2 sound but balance out the rest of the system resulted in me moving the speakers farther and farther forward until I ended up with a true nearfield speaker setup. After adjusting the position of the floorstander PZCs, I have settled in for long term listening.

The nearfield is sounding good. I'm still getting used to it, but I do enjoy the depth and the clarity I'm getting. I think I can find some more sonic gains by fine tuning the position of the speakers. They're already so close to the listening chair that I can reach my feet out and touch them, but minor adjustments to the distance and toeing may bring even more clarity to the soundstage. The current position is just a little over 4 feet from the rear wall and toed inwards about 7 degrees.

On many/most recordings, I hear instruments near the left and right speakers while the vocalist is at the back of the room. Does it need to be that way? I would probably prefer if the vocalist came farther forward towards the instruments. On other recordings (classical and some jazz), instruments fill the whole space from front to back and sometimes beyond the room walls. Which is great. For the rock and popular recordings I listen to most, it seems like more of a mixed bag. Or do I just need to get used to this presentation?

Once I got the position of the speakers and the PZCs worked out last week, I had been pretty happy with what I was hearing. But there's an important new wrinkle in all this. I've been experimenting with different power supplies for the PaceCar and have found that the Red Top battery into the PaceCar has brought the system up to a whole new level.

I tried three different power supplies: the LiFePO4 battery from Red Wine Audio, the stock switching power supply, and the Optima Red Top car battery connected with a modified Altmann power cable. The RWA power supply didn't fare well, and I immediately retired it. The wall wart power supply has been the default configuration and I thought it sounded quite good. When I plugged in the Optima battery, my first reaction was that it sounded louder. On more careful listening, I realized that everything had been increased: more detail, more dynamics, more clarity and more low-level information about the recording space. What has been most astonishing to me about the change is just how much more clear spatial relationships in the music are. I've heard how those 4 drum beats in Come Together move through the soundstage before, but I've never heard it with such absolute clarity. Surprisingly, the battery power seems to have reduced the brightness in the system. It isn't gone, but is less than what I was hearing with the stock power supply.

So things are going well. I'm looking at getting an extra pair of Red Top batteries and have already bought two battery chargers so I can keep one pair of batteries in the system ( one for the PaceCar, one for the DAC/amplifier) while the other pair are being recharged.

All that being said, I'm not actually spending all that much time listening to music. So what's wrong? The major problems I'm still hearing are an electronic glare and the brightness. The system also seems a bit 'clinical'. I'm just not really hearing the beauty of the music the way I would like to be. I've been debating with myself whether the battery power into the PaceCar has made that problem worse or not. It's fairly close, but I think the battery power supply may make that problem worse than it was, or perhaps just expose it more.

Another thing that's different is that I'm using the PaceCar instead of the Audio PC lately. I accidentally pulled the sound card out of its slot while the computer was on, and this caused a software problem which I am still working on completely straightening out. When I figure it out, I'll post instructions for the fix on the computer audio thread. In the meantime, I'm quite happy using the PaceCar.
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PostSubject: Re: Bill333's System   Sat May 07, 2011 11:54 am


Hi Bill333

The effect of instruments near the speakers but vocalist at the back of the room is the effect that Sonic worked hard at tuning out. Another way of describing it is the curved/banana soundstage or listening in cheap seats from behind the band. The way Sonic sorted it out was my rather curious set up with FS-DRTs in front of the rack, just behind the plane of the loudspeakers.

I used as my reference a system with JBL professional monitors which, while having little depth, projected vocalists and solo instruments forward strongly in a way that was consistent with live musick -- classical, jazz and brass ensemble -- I have heard personally up close.

Don't lose heart, persevere...the music will come to you.

Sonic
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Robert Harrison



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PostSubject: Re: Bill333's System   Mon May 09, 2011 5:00 pm

Hey, Bill333,

Tuning is an adventure, isn't it? In the last year, I have had so many permutations of my soundfield that I can't keep track of it. I used to keep notes years ago, but I'm too lazy for that now. Plus, notes tend to make it feel like "work" and I sometimes forget the "have fun" aspect, almost like I have to come up with that Absolute Sound so I can brag about it and show it off. Odds are what I think is great, someone else may think sounds weird.

Somewhere in the Archives, I recall reading about a fellow who loved having his vocals appear up near the front wall, almost at the ceiling. A visitor, however, didn't like that at all. So, it's a "to each his own" type of thing. It's not yours, so that's where the search for a remedy comes in. Personally, I think dipole panel speakers may contribute to the difficulty of alleviating what's ailing you presently. As I said, I have had times when the vocals would appear in the plane between my dipole panel speakers, but usually at the expense of everything else doing the same. When I get the "space" back, here comes what Sonic aptly describes as that damn curved/banana soundstage. Mad

But, hey, man! You've got a tunable room! Enjoy it some, eh? I'm trying to remember something sage to say here...

Ummm....scratch

Something about how your best results, i.e. ideas for improvement, will come at leisure? Yeah. Let's go with that, since I lack any specific advice, other than I still can't get over the tremendous results I get from just moving the speakers an inch here or there. Could it be that every room has that one special nexus point where it all comes together? If so, I haven't found mine yet. But I keep trying.

Robert
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PostSubject: Re: Bill333's System   Tue May 10, 2011 7:07 am



Hi Bill333

Robert is right about preference in sound and some people may like the vocals at the front wall. Apart from ther incident Robert describes there is this account in the archives of a Sarah Maclachlan recording where she was at the front wall and the piano she was playing extended forward thru the room and a cello moved across the room.

But you can do wonders with that room of yours and you can bring your vocals forward by moving the two PZCs in a V ahead of the rack instead of behind it possibly leaving the "evil three tubed device" where it now is.

Do share the learnings! Sonic gains much insights from you and Robert.

Sonic
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PostSubject: Re: Bill333's System   Tue Jul 19, 2011 10:50 am


Hi there Bill333

Its been a couple of months and silence about your Quads and your room-within-a-room. Hows the Tune going on in your space?

Sonic
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PostSubject: Re: Bill333's System   Thu Jul 21, 2011 7:55 am

Hi Sonic,

Most of what's been happening with my system is going on in Las Vegas where Michael has my best equipment. I've got the B-string stuff here, where it sounds OK but nothing to write home about. The sound goes up and down depending on the state of the tune, but there is a brightness I can never seem to get rid of. Most of my time and effort in this direction is going towards assisting Michael in his work in whatever ways are available to me. Hopefully the A-list equipment will be finished and installed by September.

Right now, we are having to do some rethinking because the Red Top batteries I had been counting on as a power source are pushing the pitch of the system upwards in an unnatural way. So we're reconsidering power supply options for the audio PC and the Altmann equipment.

As far as the room goes, it never holds a system back but it can't make a flawed system sound better than it is.
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PostSubject: Re: Bill333's System   Fri Sep 30, 2011 12:56 pm


Hi Bill333

How's your system coming along? Have you run in and sorted out your tuneable room and all the special gear?

Sonic had a run of really good sound over the last month or two but now something is slightly off. I am checking the racks to make sure the rods have not gone off to lean and contact the shelves.

I really need to up the strength of my middle pressure zones. This is more to do with centre girth than recessed soundstage (the awful U-shape that fools some audiophiles into thinging they got lots of depth).

My system has veered over in the direction of too much wood/warmth but though I might feel that the trebles are turned down and the upper bass puffed up, I must learn to think of my room and equipment in terms of pressure zones and flow rather than frequency variations.

Sonic
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PostSubject: Re: Bill333's System   Mon Nov 07, 2011 12:34 am

Hi everyone,

I've been quiet for a while, but that does not mean that there's nothing going on here. I recently bought some Paul Hynes power supplies and have started a series of tests to find out how they sound and how they compare to the Red Top battery and to stock wall wart power supplies.

Here are my lab notes:

The PR3 is a DC to DC converter. The setup I used puts two batteries in
parallel for 24V and the PR3 downconverts that to 12V.

The SR1 is an AC to DC converter which puts out 12V at 1 amp, and the
SR3 is its big brother which makes 12V at 3 amp.

TEST METHOD:
I substituted each power supply one at a time into the baseline
configuration. There was never more than one power supply being tested
at one time.

BASELINE:

PaceCar: Stock wallwart power adapter.
Altmann DAC: Direct connect to Red Top battery with Altmann cable.
Altmann amp: Direct connect to Red Top battery with Altmann cable.

Baseline listening notes:
Some brightness. Spatiality good, but no imaging beyond walls.


(1) PaceCar-SR1
Sounds louder. Everything seems more distinct and pronounced. Bass
notes especially sound more distinct and powerful. At the same time,
images seem larger.

(2) PaceCar-SR3
Sounds louder still than (1). Far more impact in the bass. Rocks hard.
Images have grown even larger. Soundstage seems crowded now. I hear
the character of each instrument more distinctly than baseline or (1).

(3) PaceCar-PR3 with two Red Top batteries in parallel
Does not sound louder than (2) but is much clearer and more distinct.
Soundstage is no longer crowded. Exceptionally good sense of space,
imaging and focus. Background is much quieter and more sense of space
between instruments. Good rhythm, but does not have the bass slam of
(2).

(4) PaceCar-Red Top direct
Quieter, softer, and for some reason brighter than (1), (2) or (3). I
don't hear as much detail in each note. Spatiality and instrumental
separation still quite good.

(5) Altmann DAC-SR1
Sounds very similar to baseline. Straining my hearing to detect
differences between this and baseline.

(6) Altmann DAC-SR3
Sounds a bit louder than baseline or (5). Images larger. May have
slightly more dynamic impact than baseline, but the differences are much
smaller than when going into the PaceCar.

(7) Altmann DAC-PR3
Very similar to baseline. On 'Sun King', imaging may be a little wider
and a little more focused, but detail, dynamics and overall tone seem
unchanged.

(Cool Altmann amp-SR1
Unable to power amplifier. Power keeps cutting in and out like some
kind of interference.

(9) Altmann amp-SR3
Somewhat louder and clearer than baseline. Differences not huge.
Percussion seems a little bit more distinct. Might be a little more
musically involving. Very similar to baseline. Don't think I could
tell them apart in a blind test.

(10) Altmann amp-PR3
My first impression was that the PR3 was less bright, clearer, and more
musically engaging than baseline. After going back and forth a few
times, I find that that my initial impression was exaggerated and that
the differences between the two are pretty minor.

CONCLUSIONS:
In no situation did I prefer the SR1 to the SR3. I had bought the SR1
thinking that it might be better because it weighed less than the SR3,
but I don't think it sounded as good and the weight difference is
actually very small.

Clearly, the biggest bottleneck in the system is the power source going
into the digital source (PaceCar). Putting the PR3 back on the PaceCar,
it sounds like I turned the volume up 3 notches.

The bad news is that I had hoped these power supplies would be the magic
bullet that would cure everything wrong with the system. Instead they
seem very similar to the Red Top batteries. To be fair, the Hynes power
supplies are completely untuned. I didn't even take them out of their chassis
and they are just sitting on the floor on their little rubber (affraid ) feet.
Removed from their chassis, cut the plastic tie downs off the transformer and
put them up on good wood, and they could be killer. We'll know more after
Michael visits in a month or two.

The good news is that these are AC power supplies which sound every bit
as good as, and in some situations, better than the best battery power
source we know of.

That finishes my review of the Hynes supplies. I may do a round 2 of
testing where I eliminate the sonic bottleneck at the PaceCar and
compare the SR1 and SR3 on the Altmann equipment again to see if I can
hear more differences.
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