[Crowbar]

I was referring to Wavelength.

 

[Wavelength]

Quote:

Originally Posted by little-endian /img/forum/go_quote.gif 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

LE,

I did read that post and do agree with your statement. I also want you to realize that we have characterized and held listening test's at CES with dealers, media and other even competing companies.

It was plain to hear that when converting a lossless file to another format (WAV/AIFF) which was uncompressed that there was a differential in sound that was easily heard. It more true in slower machines but we did the test on both OSX and Windows as both the MAC mini we had setup and the MacBook both had bootcamp installed with Vista Ultimate.

The thing you further have to understand is this. With a product like the Benchmark that puts the data through a upsampler to remove the jitter there should be LESS of difference in sound.

As I am sure from your alias (don't you hate these things, just say who you are) that you have some programming and therefore math background then I would suggest re-reading LaPlace and Forier work in math. This math was conceived in the early 1820's (why???) and is the basis for much of how digital audio works.

But in the end Joijwall did hear a difference from the same file. Which means as bits are not bits as they would be identical in nature.

Guys for years we have struggled with SPDIF and originally people would say bits are bits why does this digital cable sound different than that one. Now we know allot more of why that is.

Missinformation is the biggest crime in Computer Audio. The idea that the KMIXER is bit perfect. Common.... There is not a person alive who has heard the KMIXER then bypassed it and heard the difference and said they where the same.

If the KMIXER is truely bit perfect then... bits are bits correct?

I have heard the truth, what about you?

Thanks
Gordon

 

[sejarzo]

Someone please explain to this dumb chemical engineer why we cannot have a definitive answer to all of this via a simple objective test that doesn't involve listening.....please?!?!?

Why is it so hard to prove or disprove that KMIXER, or any other playback app or combination thereof, is bit perfect?

Does no device exist that can take an S/PDIF input from a computer source and convert the bit stream back to a file to be compared to the original?

 

[EliasGwinn]

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif LE, I also want you to realize that we have characterized and held listening test's at CES with dealers, media and other even competing companies.

Can you please explain in detail the configuration for this listening test?

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif It was plain to hear that when converting a lossless file to another format (WAV/AIFF) which was uncompressed that there was a differential in sound that was easily heard. It more true in slower machines but we did the test on both OSX and Windows as both the MAC mini we had setup and the MacBook both had bootcamp installed with Vista Ultimate.

This issue deals with the quality of format conversion within the media player. I make no claims in that regard.

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif The thing you further have to understand is this. With a product like the Benchmark that puts the data through a upsampler to remove the jitter there should be LESS of difference in sound.

Can you explain this in more detail?

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif But in the end Joijwall did hear a difference from the same file. Which means as bits are not bits as they would be identical in nature.

I don't want to speak for Joijwall, but I believe he was comparing the difference between his transport's internal DAC vs. the DAC1. However, I could be very wrong about that.

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif Guys for years we have struggled with SPDIF and originally people would say bits are bits why does this digital cable sound different than that one. Now we know allot more of why that is.

It is important to make a distinction between data integrity and transmission integrity.

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif Missinformation is the biggest crime in Computer Audio. The idea that the KMIXER is bit perfect. Common.... There is not a person alive who has heard the KMIXER then bypassed it and heard the difference and said they where the same. If the KMIXER is truely bit perfect then... bits are bits correct? I have heard the truth, what about you?

I don't hear any difference with the DAC1 USB when I bypass kmixer. And I am alive.

There may be some confusion about 'cause and effect' in some of your conclusions. However, I am not discrediting your opinions. We may have to look at the empirical methods a little bit closer.

Thanks,
Elias

 

[EliasGwinn]

Quote:

Originally Posted by sejarzo /img/forum/go_quote.gif Why is it so hard to prove or disprove that KMIXER, or any other playback app or combination thereof, is bit perfect? Does no device exist that can take an S/PDIF input from a computer source and convert the bit stream back to a file to be compared to the original?

A test exists with Audio Precision (AP) equipment. However, our results with these tests conflict with the testimony of one of Kmixer's programmers. The AP test indicated that the playback through Kmixer is truly bit-for-bit perfect, exact, transparent. The programmer says this is not possible because Kmixer performs a floating-point operation on all audio.

There are some people who have done data comparisons, with conflicting results. Some have determined that kmixer is bit-transparent, and some have determined that it is not.

There may be (and probably are) several variables that are not being taken into account. We may never know all the variables, simply because of the many layers and generations of computer code that makes the whole system.

So, we've performed FFT analysis' of the signal pre and post kmixer as a way to determine its affect. There is no discernible affect that we've noticed. And, please understand that we would shout loud and often if we did notice a problem. We would be telling all DAC1 USB/PRE owners to avoid kmixer so that the system sounded as good as possible. However, we have no reason to believe that there is a problem.

Thanks,
Elias

 

[sejarzo]

So...I thus take it that a similar test using the AP equipment could be also used to determine whether a playback chain all the way from a lossless file through a playback app, drivers, OS, and some external device is bit perfect or not.

And it also seems to me that if a given configuration of hardware/drivers/OS is bit-perfect with one (or more?) playback apps on .wav files, and then is found to be not bit-perfect on lossless compressed files, the errors are introduced in the playback app/plug-ins--but that could always be the case, right? There sure aren't any guarantees that freeware code is error-free.

This seems to be ripe for a truly independent test at a university.

 

[KarateKid]

I'm very interested in spending some money on a balanced amp setup. I already have balanced hd650 cables. However there are just so many choices out there in terms of balanced amps, none of which are accessable locally. The popular balanced amps out there have been out for quite some time so I'm not sure if they have the latest things in there like the lm4562s. There's so many variables like opamps vs discrete designs that is needs to be considered.

Do you think one needs to spend a lot of xlr interconnects? I know Benchmark aim to be transparent as possible when it comes to audio, I want to preserve that signature. Anyone got any tips or advice on xlr IC or a good balanced amp and whether I should go with opamps based or a discrete based?

 

[sejarzo]

Sure, build your own balanced IC's out of Mogami balanced mic cable and Neutrik XLR connectors. The recorded signal has passed through that already, and if it didn't degrade the signal between the mic and the preamp, or the preamp and the A/D, well????

 

[Ross MacGregor]

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif LE, It was plain to hear that when converting a lossless file to another format (WAV/AIFF) which was uncompressed that there was a differential in sound that was easily heard. It more true in slower machines but we did the test on both OSX and Windows as both the MAC mini we had setup and the MacBook both had bootcamp installed with Vista Ultimate.

Hi Gordon,
There are two variables that come to mind that may be affecting the test:
A) Is the player properly transforming the lossless formated data into the original data? Is it making approximations or taking shortcuts?
B) Is decoding the lossless format taxing the computer and causing transmission problems?

 

[EliasGwinn]

Quote:

Originally Posted by KarateKid /img/forum/go_quote.gif Do you think one needs to spend a lot of xlr interconnects? I know Benchmark aim to be transparent as possible when it comes to audio, I want to preserve that signature. Anyone got any tips or advice on xlr IC or a good balanced amp and whether I should go with opamps based or a discrete based?

I don't think you need to spend more then $100 per cable. If you are using balanced cabling, I recommend Starquad analog cabling. Several manufacturers make starquad cable - Canare, Mogami, etc. I also recommend Neutrik connectors.

There are many reasons why we recommend not employing balanced headphone drive systems, including significant distortion. So I have no suggestions except to avoid the topology all together.

Thanks,
Elias

 

[KarateKid]

Quote:

Originally Posted by EliasGwinn /img/forum/go_quote.gif I don't think you need to spend more then $100 per cable. If you are using balanced cabling, I recommend Starquad analog cabling. Several manufacturers make starquad cable - Canare, Mogami, etc. I also recommend Neutrik connectors. There are many reasons why we recommend not employing balanced headphone drive systems, including significant distortion. So I have no suggestions except to avoid the topology all together. Thanks, Elias

Do you mean I should not bother getting a balanced headphone amp with balance outs? Or one shouldn't use the back of the DAC1's xlr.

 

[EliasGwinn]

Quote:

Originally Posted by KarateKid /img/forum/go_quote.gif Do you mean I should not bother getting a balanced headphone amp with balance outs? Or one shouldn't use the back of the DAC1's xlr.

It is not a good idea to drive headphones with balanced cables, no matter what source. It causes significant distortion. I can explain this in detail, or you can find my posts on the subject earlier in this thread (good luck).

Don't confuse with driving equipment with balanced cables. That is not a problem. But the idea of balanced headphones has major problems.

I'll be back here on Head-Fi Wednesday. Have a great weekend!!

Thanks,
Elias

 

[KarateKid]

Quote:

Originally Posted by EliasGwinn /img/forum/go_quote.gif It is not a good idea to drive headphones with balanced cables, no matter what source. It causes significant distortion. I can explain this in detail, or you can find my posts on the subject earlier in this thread (good luck). Don't confuse with driving equipment with balanced cables. That is not a problem. But the idea of balanced headphones has major problems. I'll be back here on Head-Fi Wednesday. Have a great weekend!! Thanks, Elias

I see.

But wasn't one of the main attractions of driving headphones with balanced cable being one cable going to one cup thus eliminating any sort of cross talk? Do you think there's a better connection than single ended or is it just a myth?

 

[KarateKid]

Quote:

Originally Posted by EliasGwinn /img/forum/go_quote.gif It is not a good idea to drive headphones with balanced cables, no matter what source. It causes significant distortion. I can explain this in detail, or you can find my posts on the subject earlier in this thread (good luck). Don't confuse with driving equipment with balanced cables. That is not a problem. But the idea of balanced headphones has major problems. I'll be back here on Head-Fi Wednesday. Have a great weekend!! Thanks, Elias

Sorry to keep you. I hope you have a good weekend. However, you did not recommend using balanced headphones straight out of the DAC1, is it better to use a balanced headphone amp, even if it's still not ideal as you've explained?

 

[emmodad]

Quote:

Originally Posted by KarateKid /img/forum/go_quote.gif Sorry to keep you. I hope you have a good weekend. However, you did not recommend using balanced headphones straight out of the DAC1, is it better to use a balanced headphone amp, even if it's still not ideal as you've explained?

1/ read the thread

2/ use the search function