Benchmark DAC1 USB

[jsa]

Is anyone using Benchmark DAC1 USB? I am testing it right now, but under Vista it doesn't want to go into exclusive mode with XXHighEnd:-(
Has anyone tried this DAC before?
 
I have tested last week PSAudio Digital Link III DAC (with USB input) and no problems whatsoever. Worked great with XXHighEnd.

Anyone?

brgds
Jurek

[edward]

I'm very interested in the answer to this question as well.

I've not heard this DAC yet, but I've been reading about it. And I've read that the only way to achieve bit-perfect in Vista (using shared mode) with 16 bit music is to set the default mode to 24bit and then for the media player to output 16 bit padded data to 24 bits.

So perhaps the only way to lock on to exclusive mode is to send 24 bit data.

Peter, is there any chance of getting a version to us soon that will allow us to play 24 bit files (or at least pad the 16 bit files)? 

[PeterSt]

Is anyone using Benchmark DAC1 USB? I am testing it right now, but under Vista it doesn't want to go into exclusive mode with XXHighEnd:-(

If you say "but under Vista it doesn't want to go into exclusive mode", what exactly do you mean by that ? How do you know ? messages ?

[PeterSt]

So perhaps the only way to lock on to exclusive mode is to send 24 bit data.

Hardly imagineable. Exclusive/Shared by itself is not done "in" the DAC. It depends on how you mean to say it though;
If the DAC just isn't capable of receiving 16bit data (at 44K1), it just can't connect to the program.

Peter, is there any chance of getting a version to us soon that will allow us to play 24 bit files (or at least pad the 16 bit files)? 

And indeed that would solve it then.
It will be the next main subject (or project if you like). Padding only is rather easy.
But after I finished with what I'm doing currently. () I'm first going to work through the pending bugs.

[jsa]

Peter,
I will get you the detailed error message from XXHighEnd once I get home.
brgds
Jurek

[jsa]

Peter,
 
The message that I am getting says:
"The device currently does not support / allow Exclusive Use. It will not be bit perfect!"

I think it has to do with the fact that Benchmark operates only in 24 bits modes. Its driver does not have option for 16 bits.
 
Can XXHighEnd work with Engine #3 supplying 24bits signal?

Regards,
Jurek

[PeterSt]

Yep, that would cause it.
Further, please see my before post ... Sorry for now ...

[EliasGwinn]

Hello,

I am an applications engineer with Benchmark Media Systems.  Jsa contacted me regarding this problem.  It seems that the 24-bit operation is what is preventing XXHighEnd from locking to the DAC1 USB through 'Exclusive Mode'.

Peter, operating at 24-bits has several advantages, even if the audio is 16-bits.  For instance, operating the software's volume control will result in a greater-than-16-bits digital audio stream (because the math leaves remainders).  To reduce to 16-bits, the data must be truncated (omitting all bits after the 16th) or dithered to 16-bits.  Truncating results in serious distortion, as you may be aware of.  Dithering is acceptable, however it requires extra processing.  If the result of the software volume control was left undithered at 24-bit, the distortion would be sufficiently below the performance of currently available D-to-A chips (i.e., < -150 dBFS).  In other words, it would not have any audible degredation. 

I understand you probably have a very full plate with regards to modifying your software.  And I commend you for this open forum for feedback...I wish all software designers were as open to suggestions as yourself!

Thanks,
Elias 

[PeterSt]

Hi Elias,

Thank you for jumping in.

Peter, operating at 24-bits has several advantages, even if the audio is 16-bits.  For instance, operating the software's volume control will result in a greater-than-16-bits digital audio stream (because the math leaves remainders).

Maybe not to discuss this, and merely to put it in the context of us audiophools hence everybody knows what he/she can head for :

I don't think anyone with great care for his audio payback would want or should use software (aka digital) volume control. Note the "great care" though, of which I know that the people in here (say, this community) are about that to the highest degree. "They" hear everything, and so to speak, an i++ sounds different than an i = i + 1.

Now, unless you have a very dedicated / tuned set of amps allowing for 24dB attenuation max, 24 bits is not enough. Even 32 bits would allow for 48dB attenuation only without any losses, but, that would suffice with not too crazily over-powered amps. For me anyway (33W into 114dB @8Ohms and always playing loud).

So, using 24 bits with 16 bit data for digital volume control, honestly is not an argument IMHO.

Besides playing (original) 24 bit data - which seems "useful" enough to me to need 24 bit support in XXHighEnd - things can get rather complex;

First I'd say that using a 24bit DAC with 16 bit data, this DAC theoretically will be more (Voltage) stable at the 16'th bit. So, an advantage.
Next, however, I would be using a sigma/delta operating DAC then, which is far from my personal likings (and principles around XX) : non-oversampling.
Third, the first might not be true because of the 1-bit operating, me now not knowing whether there's advantage/disadvantage and if so, where.

Elias, I only responded to your implied "24 bits is better".
If that would be a ladder DAC (and for me without filters), yes.

Regards,
Peter

[soundcheck]

Hi there.

Peter as you might recall our session last summer at Bert's place and what difference it made
comparing e.g. a TVC and my 64bit float volume control. A TVC, such as a Django, is just slowing down the signal much more than a digital volume control would do!

24bit volume control only - sucks -  that's for sure. If you run higher quantitfication you need to dither anyhow. I am actually very positiv about dithering. It really improves the sound in my case.

Some might call the digtial volume control too "agressive". I just have a good laugh about that
statement.

Perhaps a ladder on the DAC ouput would do. But not a passive pot build as a ladder.

Beside that I believe that times of traditional DACs are over soon anyhow.
PowerDacs (PCM2PWM) will take over at the same time delivering great sound quality.
More and more chips are under devlopment. I'll stick with my PC volume control.

Panasonic is offering quite a good device at 199$.  No - I am not kidding.
Run SPDIF or HDMI into it and you'll hear what I mean.

BTW. I didn't have problems to run the Benchmark DAC1 under XP and Engine 1.

You might want to read my post over here:

http://www.phasure.com/index.php?topic=223.0

Cheers
\Klaus

[PeterSt]

Hey Klaus,

Oh ... that digital volume control is waaay better, you know that I know ...
But indeed not with 24 bits.

Some might call the digtial volume control too "agressive". I just have a good laugh about that
statement.

Regards,
Peter

[Gerard]

Panasonic is offering quite a good device at 199$.  No - I am not kidding.
Run SPDIF or HDMI into it and you'll hear what I mean.

Hi Klaus can you please tell me what's the name/model of that? (Panasonic)

Grtz

[Telstar]

Beside that I believe that times of traditional DACs are over soon anyhow.
PowerDacs (PCM2PWM) will take over at the same time delivering great sound quality.

HI Klaus,

Do you mean something like Lyngdorf Millenium or TDAI 2200?

[soundcheck]

Hi folks.

I am talking about the e.g. XR-55. Just run digital-in - analog-in sucks.
I was told that e.g. running 3 of them in a multichannel setup ( fired by 3 digital outs e.g. RME)  were
performing better than the TACTS these guys used to run before.
I had a chance to listen to a full digital chain from  Uli Brüggemann. (TACTS and RME card actively phase linear filtererd on the
PC). This I would call agressive.  I never heard better and more "shockingly" transient response before caused by the
linear filters and the PCM2PWM conversion.

With HDMI you need to be careful though, you need to check if it supports Multichannel-PCM properly - Stereo is not an issue.
I am digging into it by myself right now.

Peter: Perhaps a long term perspective for XX evolution.
(PC based filtering, crossover, convolution, volume control) .

http://www.thuneau.com/
http://www.acourate.com/

With your great basic audio engine I see quite some potential.
Perhaps you could start with a VST-plugin engine -- just as a trial.

Cheers
Klaus


 




 

[PeterSt]

Peter: Perhaps a long term perspective for XX evolution.
(PC based filtering, crossover, convolution, volume control) .

As you might expect, that indeed would be the (my) ultimate goal and Engine#3 anticipates on that (no matter it can't even do 24 bits yet ).

What's holding me back (apart from the lack of time ) is the needed DACs en enough bits (say 32) in there for appropriate volume control.
Now, it could be that your XR-55 (etc., there are more) for an overall result are better than my current setup (DAC + amps), but as you can expect it's not a matter of "just trying". It would need :

1. Buying six channels of such chains (one XR-55 would be enough I think);
2. Creating the crossovers for my speakers (which would not be a one day job);
3. At least try it with appropriate (ASIO) playback software, or in the end integrate all in XXHighEnd.

I don't underestimate such a project because

a. The DACs should workout at least as well as my current DAC;
b. The amps should be as least as good for sonic results as my current amps;
c. Although such an "active" crossover is easier to create in theory, it's not said that the result for SQ is better from it.

Then another theory (from me) :
Where such a DAC/AMP would work similarly to DSD for digital principles (at least I think it is), this would come down to SACD quality - or in the very end to delta/sigma like working, an I don't think anyone thinks that's the best.
Whether the net overall result is better still, is another question.

But hey, leaving out the crossover thing as a project, would simplify things to buying an XR-55. Right ?
Peter