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May 21, 2011 - 11:10am
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The Bit's is Bit's argument
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Yes. That's what I found in my measurements.
Low datastream jitter.
John Atkinson
Editor, Stereophile
Lower jitter than a competently connected computer? Seriously, low jitter compared to what? I reread the test section and still nothing to compare it to there or in the body of the review.
Even a computer should provide entirely competent bitstream jitter performance.
One may not, if so, it's crap hardware.
I can see the Bryston device being a better source than a computer due to it being able to use a flash USB stick which is directly connected to it. My thought is that there are many data transmission/streaming variables taking place between the computer and the hard drive that hosts the media files before it reaches the device that is used to interpret them. Dropped data packets can cause re-transmission of such packet resulting in timing related issues. If enough of these dropped packets takes place it could certainly be detrimental to SQ and increase jitter.
As I noted earlier, the lack of I/V and output circuits -- i.e., design/features/topology that would make this a TRUE (= stand-alone) digital player -- make "sense" only if Bryston's economic and market projections hold out.
So how about an even better-than-Bryston digital audio player (DAP)? Dunno if it's better, but Stephen Meijas snuck this review in back in Sept 2010 (web only). Hope JA can get 'round to measuring it some time.
> The Bit's is Bit's argument
You are using the phrase "Bits is Bit's" to construct a strawman. If you understand the technical issues, write about those.
> I asked how it was possible that a computer based front end could rival a dedicated transport
> as the computer was noisy, full of cheap parts, and was in no way constructed to audiophle standards.
You have used this description "noisy, full of cheap parts, and was in no way contructed to audiophile standards" in several threads
as a perjorative dismissal of computer audio.
Several people have reported that the Bryston BDP-1 uses an ALIX motherboard ($ 124) and a Juli@ soundcard ($ 129-140).
These are both standard items which you would dismiss as being full of cheap parts.
> I have to be missing something about this argument...If bits is bits, then the Bryston device is simply an expensive,
> well made but hard to use front end sounding no better than a computer based front end at 1/4 the cost.
Why not judge the Bryston BDP1 AND computer audio systems based on the function they provide and how well they provide it?
You said in another thread that you were using a Mac Mini.
Do you consider it to be "noisy, full of cheap parts, and was in no way contructed to audiophile standards"?
Are you dissatisfied with the sound you are getting?
Computers are cheaply made...all you need do is open one up and look at it. If it was an audio product 99% of audiophiles would put their nose in the air, sniff devisively, and dismiss the thing as junk. As it is not audio gear, it gets a pass. As I asked long ago, why is it necessary for a CD transport to meet audiophile standards of contruction and parts selection to put out a bit perfect signal while acepting a computer made to the exact opposite standards of quality and part selection as A-OK. If both put out an identical signal, a bit perfect stream, are we not overselling the need for all that construction quality and added cost for the transport...or, is the computer inherently flawed?
The answer I was given was that yes indeed, that bit perfect data stream from the junk parts was indistinguishable from the stream from the megabuck transport with the half inch case and premium parts.
OK, I bought into that. Then I read this review and what do I read, not a comparison of the actual sound the thing puts out into a DAC but build quality summary and a horror story about setup and extra gear needed to make it work as well as a description of how the user interface is vastly worse than even a basic computer based front end.
If 'Bits is NOT Bits' then the entire argument for a computer based front end suffers, something folk do not appear to support. If bits is bits then why this new device at its very high total price (need to add in all the extra stuff listed in the review)
You misunderstand my position on the parts in the Bryston...they are quality and support the price of the device itself. My question is more basic. If the computer does the same thing at 1/4 the price with far cheaper parts and far better ease of use, why buy the gold plated spread?
I am using an iMac, not a Mac Mini and yes, it, like all compters, is a mass of plastic and cheap parts...and as a result, costs 1/3 the price of this unit BUT, seems to do the same thing.
So, side by side, does the Bryston device with all its premium parts and difficulty in use, SOUND any better than my system would going into the same DAC?
That is the question and that is what was missing in the review...
And that comes back to this threads basic question. If one bit perfect data stream is the same as another bit perfect data stream and if both are produced correctly so as to produce limited jitter, why go for the higher priced spread? If that device does do something special, just what is it? And...does it sound any better? And why?
Jim, I have commented on your other thread, and questions about "bit perfect" replay (and the cost you need to pay to achieve this) are valid but I also want to introduce here the concept of computer device pollution (physical noise but more especially power)
Many of us go to extreme lengths to eliminate residual noise pollution (cables with crazy levels of sheilding/fancy power distribution boxes/dedicate power lines with seperate grounds) and then you want to stick inline/close to your hi-end components a consumer PC device (Desktop/laptop/USB drive etc).
Not for me and thats where I have my issues with computer based solutions. Hence for my money something like the Slimdevices Transporter is the ideal platform. It has both the quality and topology.
Others may disagree because PC power pollution isnt a concern for them but I am willing to pay a premium to eliminate it.
If the only product of the computer is that bit perfect stream and is not sitting n the DAC, I fail to see how any of that can effect the sound. I am using an i'Mac connected to my DAC by a 5 meter glass toslink cable. I can understand how jitter might be an issue, but how does computer noise or power supply issues get to the DAC and otehr gear 15 feet away and with its own filtered power?
Correct me if I am wrong Jim, but you have stated on more than one occasion, in the past, that driving your DAC with different sources produced different sounds, the computer feeds usually the less desireable, your own words?
RG
That is true because I am driving that DAC with a 5 meter glass toslink...If I run it with a 1 meter cable, I cannot tell the difference...
What criteria do are you using? How well it performs its function? How long it lasts? The thickness of the faceplate? The presence of audiophile approved resistors and capacitors?
That would say more about those audiophiles than it would about the computers they disdained.
Your idea is sound. Expressing it in terms of bit-perfect transmission makes it far less sound.
The concept of a bit-perfect stream makes sense when you are talking about the the music player software and the operating system's audio stack. This isn't about hardware at all; it is about the software in the path from the digital audio file to the DAC chip. (There are still a few soundcards and external DACs that only operate at 48 KHz but they aren't of any interest for serious music listening.) The developers who assembled the software in the Bryston player had to face the same issues of selecting and configuring player software, mixing software and the audio stack within Linux as anyone would in a Windows or Mac based player.
If you are sending the digital audio stream over an SPDIF or the pro audio equivalent, it has been trivial for many years to transmit the data bits and recover them in an external device. Bit-perfect transmission hasn't been an issues for a long time.
However, the receiver also recovers a clock signal. That signal may not be very high quality. Even if the DAC geberates its own clock signal, in most cases, it usually has to adapt the clock to match the long term clock rate at which the data is being transmitted. The more jitter free the clock signal the D to A process uses, the better the resulting analog audio output. The clock issues have nothing to do with the "bit perfect" issue.
If the digital stream is sent over an electrical connection rather than an optical cable, there may also be issues of electrial noise that the spdif receiver passes on to other circuitry. This question of electrical isolation has nothing to do with the "bit perfect" issue.
You misunderstood the meaning of the parts and prices example I provided. The $ 124 Alix motherboard includes a CPU chip and Ram memory. A person choosing parts for an audio PC might spend $ 90-30 for the motherboard, $ 110 for the CPU chip and $ 50-100 for the. The part that Bryston uses is far less expensive and less capable than what's in any PC sold in the last few years.
The $129-140 Juli@ sound card is the one I use and the choice of many other people assembling a PC audio system. This isn't a premium part.
Just what premium parts are you talking about? The case, the analog power supply? (Since the BDP-1 doesn't contain a DAC chip, what is the big deal about an analog power supply?)
You might ask the same question when comapring any two audio products offering the same functionality at very different prices.
Beyond the case and a few support brackets, where is the mass of plastic that offends you?
Cheap parts? Do you have a suggestion for an audiophile approved CPU chip, a Graphics chip, a motherboard, a LAN chip or a hard drive?
Bill
This would serve...
A Bryston power amp....vs.....a HP computer....Need I say more
Which is what I do every day and why I read magazines like Stereophile. I want the best sound possible within my budget. If 'A' at $1K sounds as good as 'B' at $5K and both work in my system, why buy 'B'?
An aside...'Cheap parts' is not a comment on sound quality but but simply of cost. The audiophile community constantly writes of expensive parts as indicative of quality to justify price. I guess I am not being really clear. I am finding that the sound from my 4 year old iMac (cheap parts, plastic and all) with Pure Music software through a glass toslink cable is as good or better than the sound from my Theta transport to the same DAC. A year ago I would have said that was simply not possible as the computer does music as an aside and if premium parts and exquisite build quality are a key to great sound then the computer must sound far worse....
Only it doesn't. If it doesn't, if getting mega buck sound is possible from a computer made to mass market standards, then it must call into question a fundamental precept of our hobby, that mega bucks are needed for mega sound. I still belive that is true (to a point, as much of the really high end is label and botique cache). One more often than not gets what one pays for. $5K speakers DO sound better than $1K speakers. A $4K amp does sound better than a $500 one. I just do not believe it is true for a digital front end. One can get amazing sound from a fw hundred in mass market parts, a plastic case and a good software soultion. Now consider...perhaps the biggest bang for the buck in audio today is the software bargains one can get for that computer, and those makers do upgrades! (Pure Music is coming ut with a big one in a week...free) If you want to improve the sound of yur Amp...buy a new one. If you want to change the sound of your computer front end, see what software is out there...and most software companies do free trials, th old in home demo on your very own gear...This is amazing in a world where brick and morter places are becoming rare. Anyone anywhere can try the software for free, today, now....what other part of our hobby is so easy, so subject to improvement so quickly, and is so available?
Yes JIMV, you should say more, although less might be nice too. You are comparing a pure analog device with a pure digitial device. There is no way to make any valid conclusion from that.
The demands for digital fidelity are much less rigorous. Would we spend $Ks for mag wheels to put on a lawn mower?
Your very next post makes much more sense to me. So OK, I'm glad you did say more.