Benchmark DAC1 now available with USB

[little-endian]

Elias, thanks again for your quick and professional answers.

Since some use regular CD-players to playback dts via S/PDIF for instance, I almost expected that there shouldn't be any damage done. In this operation, the player's built-in DAC will output more or less white noise all the time and nobody really cares as long as the speakers and hence the listener's ears are fed by the analog output.

 

[joijwall]

After your replies, folks, I've been listening more.
My iTunes settings are correct, Sound/MIDI is set to 24/44,1, I've tried by ear to volume match.
But listening is difficult. I tried Gordon's AIFF-suggestion and had the feeling AIFF was better than Apple Lossless, but by so little. And I thought suddenly VLC didn't perform Cosi Fan Tutte as well as iTunes (used to be other way round), and Linn vs LinnDAC was dashing over the finish line today as one.

Still, what I hope for is to get my MacBook/DAC1 USB to sound better than my Linn CD. I thought reading from the harddrive was superior to reading a CD, and I was pretty sure DAC1 was a better DAC than the Linn one. But I can't hear the great difference.

So where did my hopes go wrong? Have I missed something?
Thanks! Joachim

 

[little-endian]

Hi joijwall,

actually getting an answer to your question is straightforward if one excludes any voodoo and proceeds rationally instead:

Since the logic is much more powerful than our hearing abilities, a good question for the beginning is "what can affect the analog quality which is "reconstructed" on a fixed digital basis?".

The right answer which can be proven is "data integrity and time".

The first can be examined by recording the S/DPIF-output of your different sources and comparing the result with the original file or data from the CD. If there are no differences (besides the offsets of course), then there is only the variation in time left to explain sonic differences.

And since the Benchmark DAC1 doesn't care of the last parameter due to its ultralock system (as advertised), pushing jitter artefacts far below the hearing threshold, you may lay back and relax becoming aware that imagination is something great but really no impartial counsel.

 

[helian]

Hi Elias,

I just got a DAC1 USB. I'm using it with Linux, so I'd like to know if there is any plans on adding a linux section to Benchmark Audio-Wiki.



Thanks

 

[joijwall]

"The first can be examined by recording the S/DPIF-output of your different sources and comparing the result with the original file or data from the CD. If there are no differences (besides the offsets of course), then there is only the variation in time left to explain sonic differences."
I'm with you this far, little-endian. How do I record and compare S/DPIF-output and CD-source? What do you say about my presumptions that HDD reads data better than a CD player, and that DAC1 should convert extremely well? It's easy to hear difference between a Linn Majik CD and Linn Akurate CD. Shouldn't I hear some difference between Linn Majik CD and MacBook/DAC1? Thanks! Joachim

 

[little-endian]

Hi joijwall,

Quote:

Originally Posted by joijwall /img/forum/go_quote.gif How do I record and compare S/DPIF-output and CD-source?

Well, the effort actually depends on the data rates you're trying to compare. For instance to do that for 96kHz/24Bit or even 192kHz material, one will face mainly two problems: The equipment capable of recording that rates over S/PDIF, source capable of deliver such rates over S/PDIF and of course the old annoying topic copy protection.

But let's stick with 44.1kHz/16Bit for now like it comes from regular audio-cds. The deal would be to record the player's output with a sound card featuring a S/PDIF input (~ 20 EUR) and compare that result with the files you get via DAE (Digital Audio Extraction) from your CD.

If the output of your player is bitperfect (unfortunately not all are, sad but true) and the transmission is fine, both files (the recorded one and the "ripped" one) should match. There might be missing / repeated samples, also sporadical within the track (I encounter this with my Transit USB, still have to investigate the reason) but the proofe is still valid.

Quote:

Originally Posted by joijwall /img/forum/go_quote.gif What do you say about my presumptions that HDD reads data better than a CD player, and that DAC1 should convert extremely well?

It depends on what you mean by "reading better". On physical layer, every readout or storage is analog, hence varies in quality (for instance, when reading a CD a high-frequency signal is digitized and processed further) but at the end, what counts is if the "user data" (the raw data before the error correction stages may contain errors) is free of errors or not. There are debates about different amounts of jitter though. However, this doesn't affect the data integrity when within the threshold levels.

Quote:

Originally Posted by joijwall /img/forum/go_quote.gif It's easy to hear difference between a Linn Majik CD and Linn Akurate CD. Shouldn't I hear some difference between Linn Majik CD and MacBook/DAC1? Thanks! Joachim

If you use different players or DAC configurations, the sound may be different although they are fed by the same data, yes.

Even if it might be bad for your stomach one hint at last: The undoubtful exclusive and well produced Linn players - and even if their drives are of highest quality materials - won't deliver you other data than the cheapest, rattly PC CD-ROM for ~ 15 EUR.

Amazing, huh?

 

[infinitesymphony]

The Linn Majik CD costs $3,500 while the DAC1 USB costs $1,275. If they sound the same, doesn't that speak for the value of the DAC1?

 

[Wavelength]

Quote:

Originally Posted by little-endian /img/forum/go_quote.gif Hi joijwall, Well, the effort actually depends on the data rates you're trying to compare. For instance to do that for 96kHz/24Bit or even 192kHz material, one will face mainly two problems: The equipment capable of recording that rates over S/PDIF, source capable of deliver such rates over S/PDIF and of course the old annoying topic copy protection.

Guys,

Really bits are not bits as we have found out. There is all kinds of things that make up sound. In the case of the computer why SHOULD the AIFF sound different from the Losless? They are identical files, heck the AIFF was created from the Lossless.

Joijwall,

Maybe you better give us the run down of your system in complete detail, including the ac and audio layout and maybe I can see something.

We have actually found several user's trying to isolate computer power supplies from the audio. This is fine if the computer section floats the earth connection (center one on a 3 prong). But if it doesn't it causes a small ground loop that can steer the output to sound poor.

Heck even to say that the USB cables can sound different. The best inexpensive cable is the Belkin Gold 2.0 USB. We actually found the Kimber with the ferrites on both ends to sound poor compared to the Belkin. But these are easy to remove and Ray has been made aware of this.

Anyways spending hours looking at bits is basically a waste of time.

Thanks
Gordon

 

[EliasGwinn]

Gordon,

I have to respectfully disagree with every point in this post.

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif Guys, Really bits are not bits as we have found out.

Bits ARE bits. Data is data. Data sets are finite, discrete values that can be directly compared with certainty. Its just math.

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif In the case of the computer why SHOULD the AIFF sound different from the Losless? They are identical files, heck the AIFF was created from the Lossless.

AIFF's are not usually created from Lossless-coded files. They are usually created from the raw data. If they sound different, its because the data (bits) have been changed.

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif We have actually found several user's trying to isolate computer power supplies from the audio. This is fine if the computer section floats the earth connection (center one on a 3 prong). But if it doesn't it causes a small ground loop that can steer the output to sound poor.

It is a BAD idea to float the ground on a computer power cord. If the DAC1 and computer are plugged into the same power outlet, there will be little chance of a ground loop. BTW, if ground loops are a problem, it will cause a hum. If you don't hear a hum, you don't have to think about this. BTW, we've only had one case of a DAC1 USB with a hum, and this customer was using a laptop whose power cord had no ground plug.

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif Heck even to say that the USB cables can sound different. The best inexpensive cable is the Belkin Gold 2.0 USB. We actually found the Kimber with the ferrites on both ends to sound poor compared to the Belkin. But these are easy to remove and Ray has been made aware of this.

If a USB audio device is sensitive to different USB cables, such that the sound of the device will change with each successive cable, perhaps the USB device is not built properly.

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif Anyways spending hours looking at bits is basically a waste of time. Thanks Gordon

Analyzing and understanding the effect that various sources have on the digital data is very important. Several sources will modify the digital data (often to horrible ends). This includes software and hardware. In these cases, one could spend hours trying to fix the problem by changing cables, power cords, internal components, auxiliary components, etc, etc, etc (ad nauseum), when the problem was simply an improper setting in a menu somewhere.

Thanks,
Elias

 

[little-endian]

Well, Elias was faster than me. I totally agree with his disagreement.

The digital technique may be one of the most ingenious one ever invented but is unfortunately also one of the most poorly unterstood.

I just want to add something here:

If we speak about digital information, it even doesn't have to consist of bits actually. Every number system or alphabet is per se digital because it has a well defined, discret character set, where nothing can exist in between. Thus digital <> bits but digital --> bits for instance (one possible char set of infinite).

When you read a book, you're indeed retrieving digital information since simple text is purely digital although it is always represented in an analog form (for instance the paper and ink whose quality may vary).

Hence, digital data exists only on a logical level beyond physical inadequacy.

That is the big deal.

Never forget that.

End of philosophy.

 

[Wavelength]

Elias, Little-Endian;

Guys go back and read the post!

I suggested that he take a Lossless file and convert it to AIFF. The instructions were clear and easy. We have done extensive tests on this and yes the Lossless files on both PC and MAC are pure and the same and are a bit match to their uncompressed formats of WAV/AIFF.

The question to you is... if the bits are bits then why don't they sound the same?

Guys I have been draining my brain trying to find out why on the PC the applications all seem to sound different. If bits are bits then why? They are all the same files going to the same place.

I don't think it's bits are bits not yet at least.

Elias,

Ground loops often occur because of the computer. If you take really high end advice then all the components would be floated except the preamplifier. That (I am not kidding here... story to follow) is ground to a 1/2" steel post in the ground at least 2 feet.

Jonathan Valin got sited by Cincinnati Gas & Electric for this very setup. They came out and disconnected his entire power to his house.

Most of the noise caused by ground loops in computer systems stem from the fact that all grounded devices need to be plugged into the same outlet. But most of these audio guys want to plug xyz into power conditioner A and then the computer into the wall. If there is a ground potential between the units then ground loop noise occurs.

We found that if you used the 3 prong plugs on some early MacBooks and Intel Core Duo Mini's that ground loop would occur and the user needed to use a cheater plug to remove the ground.

This is no big deal as the common ground will still exist between the USB dac, computer and the rest of the system. Unless you use like an opticis cable to isolate the computer from the dac.

Thanks
Gordon

 

[Scrith]

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif if the bits are bits then why don't they sound the same?

They sound the same to me. With regular tests and with blind tests. Same with my wife. Have you tried blind testing or are you reiterating the opinions of many people that tend to echo the same opinion they read somewhere over and over again here on the internet?

 

[little-endian]

Hey Gordon,

no need to get upset here.

I have read your post - in opposite to you when it comes to mine I'm afraid.

You're invited to read my post #1428 to find the answer to your question.

You should allow yourself to trust a professional engineer from a company which manufactures these devices and one who is indeed layman in comparison but has understood the most important basics pretty well (me) a bit more.

Thanks,

little-endian

 

[Crowbar]

Isn't defeating the ground connection on a computer illegal? A computer is a significant RF radiator.

little-endian: he is an engineer, and he does manufacture DACs.

 

[little-endian]

Quote:

Originally Posted by Crowbar /img/forum/go_quote.gif little-endian: he is an engineer, and he does manufacture DACs.

Yes, of course I know. That's why I mentioned it.

And without flattering too much, Elias' support is one of the best I've ever seen from a company - really excellent. Many, many thanks at this point again!