Article: Weiss Engineering DAC202 Review

[barrows]

"then the inability of those involved in said evaluation to discern any difference must mean that there is no difference. Right?"<br />

<br />

Emphatically, wrong.<br />

<br />

There is a whole thread on these forums that brings up the many problems associated with so called "scientific" blind testing. If you would like to learn why blind testing is largely irrelevant, I would suggest reading the thread that already exists, and commenting there. No need to start a whole new discussion on this topic here. <br />

Back to the Weiss 202...

[artk]

<br />

The problem with double blind studies is they demonstrate that much of what the high end audio industry is selling is actually a myth. Take three DACs, two in over 5k category, and a good one for a 1k or so, I’ll bet my bicycle seat all the “golden ears” can’t tell the difference. It’s amazing how sound quality improves when listeners see the price tag. <br />

[The Computer Audiophile]

ArtK - Do you have any data to base your opinion on or are you just using your hearing and listening skills to make generalizations across an entire industry?

[artk]

Pretty much every review I’ve ever read is measurement free, just full of anecdotal value judgments. My anecdote is from my local Hi End retail store. They were dutifully demonstrating how a very well know 5k DAC sounded so much better than a unit a quarter it’s cost. I got lucky; the sale person got called away for a few minutes so I had a chance to swap cables. The sale person came back and continued point out the flaws of what was actually the high priced spread but he thought was the cheap unit. He would then switch to the cheaper unit, thinking it was the high priced spread, and point out its superior attributes. Just one more anecdote for an industry built on anecdotes.

[gmgraves]

That's the general consensus anyway. Ostensibly, DBTs have been performed where an analog signal has been "round-tripped" in a series of 10 modestly priced ADC/DACs and then compared to the original analog signal and no one, in dozens of tries, could tell the difference between the original analog program and the same program that had gone through 10 conversions! Kind of hard to believe, isn't it?<br />

<br />

A good discussion on listening biases and how they affect people's perceptions can be found at: <br />

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/>

<br />

Very interesting. I'm going to take a previous poster's advice and go read the discussion on this site about the "fallacy of DBT in audio evaluation" (if I can find the thread).

[The Computer Audiophile]

Art - Your anecdote is just another shortsighted claptrap that proves nothing except your desire to troll forums and retail stores (if the story is actually true).<br />

<br />

Computer Audiophile is for people who enjoy this wonderful hobby and see tremendous value in improving our music listening experience. Based on all your posts here you clearly have an insurmountable grudge against the industry even though it is no different than every other luxury goods industry. Your continued comments tell much more about you than the subject matter in the comments. <br />

<br />

[4est]

Would love to see how long Art could ride his bike before he had to sit on the remaining post after losing his seat!

[Tipper]

Art<br />

I describe myself as a recovering audiophile.<br />

I’m also fascinated by DBT and I much prefer to trust what can be measured. <br />

I’ve been a Hi Fi and music enthusiast for over 25 years and I still read reviews (even though I think they’re pretty pointless) buy the occasional component and thoroughly enjoy the whole process. I build rather than buy these days and spend many happy hours tinkering with what I have hoping that somewhere I’ll improve the sound I can hear. I try not to take it all too seriously and bear in mind what I hear may not be what another does.<br />

As Chris points out it’s no different from any other luxury market and if it gives people pleasure spending their money on expensive Hi Fi I don’t have problem with that and neither should you.<br />

It helps our economies, provides entertainment, brings people with a common interest together and most importantly, hopefully gets people listening to music and anything that does that in my eyes can’t be a bad thing.<br />

Here everyone is given a chance to state their opinion. However, if you wander into a church and shout “there is no god” you can hardly expect not to get stones thrown at you.<br />

These people are enjoying themselves discussing an expensive Dac. I may not think it’s worth the money and you obviously don’t. But, isn’t it easier to leave them to it?<br />

[Charles Hansen]

George said, "I'm going to take a previous poster's advice and go read the discussion on this site about the "fallacy of DBT in audio evaluation". I've got some better advice. Leave this forum and don't come back. You are wasting our time.<br />

<br />

You used an anecdote. Here's one for you. Before CES we set up our system for three weeks to fully burn in. During that time I became very familiar with the way it sounded. When I got to the show, our crew had the system all set up to duplicate the sound we got at the shop.<br />

<br />

But something was wrong. It just didn't sound right. I listened to several CD's to be sure. Then we started trying to figure out what the problem was. At first we were focused on the room acoustics, trying different absorbers. Nothing worked.<br />

<br />

Then after four hours, in frustration I leaned against the wall and kicked the floor. As I looked down, there was one power cord (for the preamp) that was missing ONE wood block that held it off the carpet. We put that wood block in and everything was fine. Sounded just like it did at the factory.<br />

<br />

Explain that one to me. I can't. I don't even know how wood blocks work....

[BobH]

anecdote antidote or is it just another story?

[The Computer Audiophile]

<I>"I've got some better advice. Leave this forum and don't come back. You are wasting our time."</I><br />

<br />

That's a bit harsh Charlie. In person George seems like an amicable guy. We met in San Jose last week.

[labjr]

<i><br />

"Explain that one to me. I can't. I don't even know how wood blocks work...."<br />

<br />

</i><br />

<br />

The snake oil was just working as claimed.

[jhbpa]

Anything special needed?<br />

<br />

What is included in the box?

[The Computer Audiophile]

Hi jhbpa - I'm not sure if a FireWire cable is included in the box because I picked up the unit from another manufacturer who "intercepted" it on the way to me. The cable I really like when using the DAC202 with a newer Mac is a simple FireWire 800 to FireWire 400 (9 pin to 6 pin). Here is the one I used -> http://www.microcenter.com/single_product_results.phtml?product_id=0315146<br />

<br />

I also have a Monster Cable FireWire 400 cable that I used with my PC and it worked just the same.

[Charles Hansen]

>> That's a bit harsh Charlie. In person George seems like an amicable guy. <<<br />

<br />

I'm not saying that George isn't a nice guy. But it's clear that he has zero interest in improving the sound of his system.<br />

<br />

You probably weren't around to see those kind of people turn the first audio discussion group (on the Usenet, remember that?), rec.audio.high-end, into a cesspool of bickering. It's a strange mentality when one believes everything sounds the same and yet that person spends their time on audio forums where people discuss the different sound of components.<br />

<br />

Other forums have had to restrict the discussion of double-blind testing to specific forums to prevent chaos from taking over. But it's your forum, so you should run it as you see fit.

[Charles Hansen]

>> The snake oil was just working as claimed. <<<br />

<br />

Gosh, what an insightful comment!<br />

<br />

Instead of being snide, why don't you open up your mind? Go down to Target and spend $15 on the game called Jenga. Inside are 50 wood blocks. Prop them under all of your cables, interconnects, and power cords so that they are not touching the ground.<br />

<br />

Then get back to us. If you can't hear the difference, you can always just play the game. If you don't like games, give it to a nephew or something. C'mon. It's only $15. Give it a try!

[barrows]

weasel grease, full moon rituals, sacrificing virgins, etc.<br />

If it might improve my enjoyment of music, I'll give it a try.

[gmgraves]

"I'm not saying that George isn't a nice guy. But it's clear that he has zero interest in improving the sound of his system."<br />

<br />

I don't see how you can say, from what I've written, that I have zero interest in improving the sound of my system.<br />

<br />

My original post was to ask Chris what he thought of the fact that many very well conducted double-blind and ABX tests have shown, that when listeners didn't know what they were listening to, all differences between DACs disappeared. <br />

<br />

I never even said that *I* believed it. <br />

<br />

But I am an engineer and I do understand electrical theory and psychoacoustics. I do know that there is a such thing as sighted and expectational bias, and that human beings are VERY susceptible to it and no one is immune. Now, I have heard many DACs and I think they all sound different in spite of the conventional wisdom that says otherwise.<br />

<br />

In fact, my own DAC, (a Sonic Frontiers DAC 2.6) was recently upgraded by me from a pair of Burr-Brown OPA134s in the output to a pair of National LME49710s. The difference was immediately noticed not just by me, but by several friends. The main difference between the two op-amps were that the Nattys had much lower noise (2 µV/root Hz vs. 8 µV/root Hz) and this we could hear in quiet passages, and the LME 49710s were designed to have symmetrical slew rates while the OPA134s were not. This manifested itself in greater sense of clarity which one would expect due to much lower distortion. In fact, the low distortion advertised for these National op-amps is what caused me to change out the Burr-Browns for them. I would liked to have done a DBT between a DAC 2.6 with the original op-amps in them and my modified unit, but unfortunately, I know of no one who owns another DAC 2.6, and the time it would take to swap-out the op-amps in my unit would negate any semblance of accurate aural memory and it would be hard to disguise the "surgery" between listening sessions anyway. I have listened long and hard to this modified unit and have DBT'd it against a friend's older MSB unit. I recall that they were virtually indistinguishable from each other before I modified my 2.6, and my DAC now sounds much cleaner than his MSB. So I'm pretty satisfied that this upgrade was not merely a placebo. <br />

<br />

On the other hand, I also know that audio is simply not that difficult to quantify, amplify, or transmit. Compared to many signal types, audio, due to it's low frequency bandwidth does not tax conductors, amplifiers or digital processors. Collective electronics knowledge understands and has modeled every single aspect having to do with the capture, storage, retrieval and amplification of audio frequencies. We know, for instance, that at audio frequencies, and for relatively short runs (less than 20 feet, for instance) there is nothing that one can do to wire and connectors ALONE that would have the slightest effect on the audio signal being passed. If an interconnect or a speaker cable can alter any parameter in any way which would have any affect on the sound of an audio system, then those cables are not just cables, but are designed purposely to be filters and that can easily be measured. <br />

<br />

I am very interested in making my system sound more like real, live music. I am a recording engineer who started making live recordings because I thought I could do better than commercial releases. I have proven, to my satisfaction, at least, that I can. The better my system sounds, the more like the real event my recordings sound. But I know that some things simply cannot be true and usually these things can be proven by a simple DBT. Either they make a difference in a double-blind environment, or they don't.<br />

<br />

What bothers me the most about the previous poster's comment that I "obviously" have no interest in improving the sound of my system is the implicit admonition contained in that sentence which basically says "Our minds are made up, there is no place here for opinions other than the "party line", and your comments, especially those which ask the hard questions, are not wanted here."<br />

<br />

I hope that I am wrong about this. Believe me, I know what you are saying about rec.audio.high-end but I am NOT Arny Kruger and I do want to discuss the sound of different components.

[barrows]

"But I know that some things simply cannot be true and usually these things can be proven by a simple DBT"<br />

<br />

How can you "know" this? Respectfully, this "knowledge" that you appear to be referring to is exactly the problem when closed minded engineers approach audio design. They assume that they "know" and can measure everything about audio signals. This point of view is neither accurate, nor scientific in nature. True scientists accept that they "know" very little, and remain open to possibilities of learning more.<br />

Talented audio designers accept that they do not "know" everything, and are open to listening, experimenting, and learning about what approaches may sound better.<br />

The thread on blind testing is here:<br />

<br />

http://www.computeraudiophile.com/content/Controversy-ABX-testing

[artk]

Audio is so magical that signals that are electrically identical, and sound the same when you don’t model and price of the equipment, suddenly change when you know the price tag? Science doesn’t mean you’re open to any unfounded crackpot idea. Ideas require independent validation. If you can’t discern differences by measurement and you can’t discern differences by repeatable verifiable testing, than you’re claiming magic.<br />

[gmgraves]

Are you saying that there aren't things that you just know? For instance, you KNOW (one would hope) that you cannot fly by jumping off a roof and flapping your arms. If you're trying to say that all one needs to do is "open one's mind" in order to fly like this, I invite you to try it first, and then get back to me. :^)<br />

<br />

But seriously, have you ever seen a cable manufacturer try to explain why his cables "sound better" than than the competition? It's all technobabble. He can't explain it. There's nothing to explain. If expensive cables can remove distortion, flatten frequency response, "time-align" the signals passing through them, you would think that the companies making the cables would have ground-breaking research into conductors which would spill-over into other disciplines where signal "purity" would be crucial, maybe even life-saving. But these cable companies like Nordost and Kimber et al don't even have patents on these "breakthroughs" in wire design. Because there are none. <br />

<br />

I agree that we don't know everything, I certainly don't, but I suspect that a lot of these "talented audio designers" of which you speak are trying to sell components in a very narrow and highly competitive market where product differentiation is the difference between success and failure.<br />

<br />

I know several well known and extremely talented audio designers. They use the best materials available, the best components and the latest devices in time-proven circuit configurations in order to get the best out of their products. They will be the first to tell you that there is no magic involved, simply sound engineering practices and the highest quality components and build methodologies. <br />

<br />

BTW, Thanks for the link to the DBT debate.

[One and a half]

Yes... measurements need to be very accurate and resolve closely to that of the human listening experience.<br />

In a nutshell, the detection needs to be at this level:<br />

<br />

- The threshold of hearing corresponds to air vibrations on the order of a tenth of an atomic diameter.<br />

<br />

- 130db Dynamic Range<br />

<br />

- Pitch discrimination within 1Hz (or better) (A good oscillator can do this, OK)<br />

<br />

Until instruments that can *really* measure the same as our hearing, then we determine sound differences by measurement. The difficulty is that once the signals leave the ear for processing by the grey matter, all sorts of variables start to manifest themselves, which are clearly *undefinable* at best and could never be standardised. <br />

<br />

It is easy to measure audio criteria with microphones, and spectrum analysers, distortion meters but they don't come close to human hearing, never will. It's a very rough measurement in comparison. <br />

<br />

In summary there will always be differences in audio perception to different people, even when the rough measurements are taken into account (generally). Whether DAC A is better than DAC B is a choice up to you, ultimately, or what you can live with that makes you enjoy music between the two. <br />

<br />

The difficulty these days is that the world is close on the internet, yet many brick and tile dealers don't have the range to stock what's totally on the net. <br />

<br />

It's forums like this one, where collective opinions can make some sense of at least to try and find a solution for computer audio. Daniel Weiss has by all accounts improved on his previous DACs with some fortitude, yet the tall poppy syndrome prevails to a degree. Pity the new Weiss DAc is so expensive, there's no way I could justify one in my living room, but the DAC does provide a new reference level for which Weiss needs to be recognised, and that's a good thing. <br />

It keeps the competition on their toes and for us audiophiles, something to natter about and contemplate when to open the wallet..<br />

<br />

Cheers,<br />

[jonmarsh]

If you genuinely want to see an engineer talk about the physics behind cable technology and see actual electrical specs on cables, I'd recommend you pay a visit to the Cardas site. George Cardas is not a snake oil salesman. <br />

<br />

Being an engineer, I'm more comfortable with his products and how he presents and discusses them than the majority of cable manufacturers, though I do have Ayre cables also, which are developed by Ayre (yes, that includes a lot of listening tests) but built by Cardas. Even within the Cardas product lines, there are significant differences, and which ones will be the best choice depends on the overall system configuration, so while there are systems that work well with Cardas Golden Preference, I generally prefer Golden Reference and Cardas Clear, if the budget permits. <br />

<br />

Naturally, if you don't hear any difference between these and 12 gauge zip cord from Home Depot in your system, you can save yourself a lot of money. It's like the difference between how a recent speaker design I completed sounds in a system at my ex's oldest sister, versus what it sounds like at home. For some reason, there seems to be a difference between what the Technics receiver and CD player sounds like, versus a Berkeley Alpha DAC and an all Ayre amplification path. And with that Technics receiver, you won't hear meaningful differences between AWG14 zip cord and Cardas cables, in all likelihood. In the bigger system, with these specific two ways, I can reliably identify the difference between Cardas Golden Reference speaker cables and Cardas Golden Presence (preferring the former). <br />

<br />

But then, even the ex inlays understand and have experienced it, as her son has an Ayre Integrated and a decent mid fi DAC, a PS-Audio DL-III, and this is also, to their non audiophile ears, in a different class from the Technics equipment. <br />

<br />

But of course, all DACs and amplifiers sound the same, don't they? ;^)

[barrows]

"If expensive cables can remove distortion, flatten frequency response, "time-align" the signals passing through them, you would think that the companies making the cables would have ground-breaking research into conductors which would spill-over into other disciplines where signal "purity" would be crucial, maybe even life-saving. But these cable companies like Nordost and Kimber et al don't even have patents on these "breakthroughs" in wire design. Because there are none."<br />

<br />

Nordost also makes very special wiring for aerospace (used in the space shuttle project as one example) and high tech medical devices (including wiring used inside the body for prosthesis). While I agree that some cable companies are suspect in the marketing technobabble, Nordost is not one of those companies, and, they are pioneering new ways to measure cables using actual music signals and time delay analysis to support their theories on cable design (this is also a joint project, funded by Nordost and one of their competitors, so not just self serving). Of course a cable cannot "time align" a signal, but it can do less damage in the time domain than a competing design.<br />

<br />

RE: audio design engineers, how do you feel about feedback? It is generally accepted by most well respected audio designers that high amounts of loop feedback sound bad, but measurements "prove" that large amounts of feedback "improve" performance. Magic? Placebo?, or is there just something about audio signal reproduction which is not entirely understood or measureable at this time?

[Tipper]

I used to work in an avionics communications Research and Development Dept developing aircraft and tank communication systems and I don’t remember any particularly special cables being used.<br />

I would have thought in such applications everything that could contribute to the clarity of communications was pretty vital.<br />

It was hard enough just to get a set of commonly used directions and instructions understood in these environments particularly when the operators were under stress. <br />

Maybe a lot has changed since then<br />