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Just received a press release email from Benchmark:***Benchmark Media Systems Announces First Native 96-kHz 24-bit "Advanced USB Audio"***
Is this really the "first"?
Follow Ups:
i will prefer better power supply, better regulation, discrete output stage instead of opams..
Regarding the op-amps - yes there are too many. Initially, I too was not blown-away by the sound of even the best op-amps modded into the DAC-1. It was very good, better than most expensive DAC's, but lacked smoothness on the vocals. DAC's such as the Northstar with discrete transistor output were much more smooth. I was ready to use a discrete transistor stage in my new SS DAC design.However, I recently eliminated one op-amp from each channel and changed the current-flow in the circuits. These changes made it smooth on vocals and improved the front-to-back layering, bringing it on-par with a discrete transistor output.
I'm back to using op-amps in my new SS DAC. They have much more capability and are easier to design with. DC-servo for instance is much more straight-forward. It believe that most of the bad-sounding op-amp designs are due to the design, not the op-amps. There are some excellent sounding op-amps available now.
I was hoping Benchmark would announce their next generation DAC, like "DAC-2," that most importantly would offer discrete output stage and hopefully "defeat" button for the 110 kHz Ultralock asynch upsampling.
I would love to hear this next to a firewire Apogee MiniDac.
No, my USB tubeDAC, the Spoiler does 24/96. They are not the first.
I guess they are saying that a 3rd party driver is not needed. I can see that for Vista, but not for WinXP and Win2000. Yes, these drivers work with my DAC as well, but they don't sound good, so what's the point in mentioning them?
The main culprits for bad computer audio playback are:Software mismanagement:
- Poorly designed software volume control
- Truncating to 16-bit
- Sample-rate converting
- Other DSPHardware mismanagement:
- DAC, etc unable to handle high jitter levels common with computer outputsAn ideal computer-audio playback path will get the digital information to the DAC without corrupting it whatsoever, just as we expect from any high quality transport.
The USB audio solution developed for the DAC1 USB is tested and proven to be bit-transparent. This means, if the media player (iTunes, etc) is set up properly, every digital bit that was originally present in the audio file will be perfectly transmitted to the DAC1 USB. This was tested using "Bittest", a bit-tranparency test from Audio Precision.
Further, due to the UltraLock clocking mechanism, the DAC1's immunity to Jitter make it the perfect counterpart to computer-based digital audio playback.
In fact, when playing a 96/24 test tone from the computer's USB port, the performance from the DAC1 USB is just as good as from a high quality transport.
Hope this helps!!
Elias Gwinn
Engineer
Benchmark Media System, Inc
http://www.BenchmarkMedia.com
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I do not have Vista yet, so no.
The generic usbaudio driver in Vista has been substantially rewritten (to fit within the UAA and WAS frameworks).I wasn't sure in your post whether your remarks were directed at the XP driver or the Vista driver (the Benchmark DAC press releases states that it will run at 96k on the vista driver).
... then it is indeed a "first".I wonder if it will work in asynchronous mode (XP usbaudio.sys only supported adaptive and synchronous). If so, this will finally address concerns about USB jitter.
I've been trying to find out more details about what's different in the Vista usbaudio driver but most of the "public" information is old. Possibly Microsoft may reveal more at WinHEC 2007.
PS - Interestingly, Roland/Edirol recently released Vista compatible drivers for the StudioCanvas SD90, which I own. I suspect it's based on an proprietary asynchronous implementation (since the SD90 has fixed internal clocks that can only be changed by power toggling the device). However, the SD90 only supports 44.1 and 48kHz sampling rates (even though the ADC and DAC is capable of 96kHz), because it is a USB1 device.
Actually, the 'backchannel' endpoint is used for both adaptive, and asynchronous modes, so does not prove anything.
According to the protocol:For adaptive audio source endpoints and asynchronous audio sink endpoints, an explicit synch mechanism
is needed to maintain synchronization during transfers. For details about synchronization, see Section 5,
“USB Data Flow Model,” in the USB Specification and the relevant parts of the Universal Serial Bus
Class Specification.
.....
An adaptive audio source IN endpoint is accompanied by an associated isochronous synch OUT endpoint
that carries Ff. An asynchronous audio sink OUT endpoint is accompanied by an associated isochronous
synch IN endpoint.
Actually XP has asynchronous support as well. If you plug in an Audigy 2NX without installing the creative driver you can see asynchronous USB audio at work and of course it does 24/96.
Cheers
The Audigy 2NX doesn't use the generic usbaudio driver, it installs a Creative driver (through Windows Update, or from a service pack).If you read up Microsoft's description of the XP usbaudio driver (in one of the WinHEC presentations) they clearly state it only supports 32, 44.1, 48k sample rates, 16 bit, and adaptive/synchronous modes.
Sorry Christine,sometimes Google is not the truth. Try plugging a Audigy 2NX into XP without installing the Creative drivers. You will find that it works in 2-channel stereo mode using asynchronous USB audio. There is one other USB card that works this way.
And the standard driver does indeed support 24/96 at least it does on my XP box with an Audiotrak Optoplay.
Cheers
Thomas
*** Try plugging a Audigy 2NX into XP without installing the Creative drivers. ***Yes, but is it using usbaudio.sys?
Just because the drivers weren't sourced from the installation disk doesn't mean that usbaudio.sys is being used.
Sure, just try it ...
Can you point me to exactly where does it state that ntrack 5 supports WASAPI exclusive mode?I am surfing the ntrack web site right now, and I can't find any evidence that it supports WASAPI exclusive mode.
There's no mention in the change log (which I have linked to below).
The latest version of the User manuals states that it supports "WDM, MME, Asio, DirectSound" - no mention of WASAPI or exclusive mode.
You can just download and install it. It has some free trial period.When you go to Settings-> Audio Device you get a popup with all availabe devices. On that Window you need to extend into advanced and there you can select WASAPI (experimental)
I have not quite got this to work and I have not had the time to follow up with them. The furthest I have managed to get is with the open source Cmedia driver from Dogbert but it did not work bit perfect and was crackling pretty bad.
I am trying to get a small WASAPI player put together for experimentation.
Cheers
.
Just do a print screen from device properties in Hardware Manager and show me that it is using the usbaudio.sys driver.Shouldn't take more than a few minutes if you have the device handy.
Sorry to butt in with an OT question, but.... how does one print the screen as is? I have a PrtScn button on my keyboard, but nothing happens when I push it. This would be a neat poiece of info to know so appreciate any tips you can share! Thanks!
marc g. - audiophile by day, music lover by night
to put a bitmap of the current window or full screen into the clipboard.You then need something to view it in. I frequently open Word and paste it in to that - simple to control margins, image size etc.
Sure, where do you want me to send that? I add my mail and you can let me know.
Thanks for helping by the way.I'm sorry to be a pest on this, but I find this very intriguing.
On page 15, it clearly states:In Windows Server 2003 and earlier versions of Windows, including Windows Me and Windows 98, usbaudio.sys supports the adaptive and synchronous endpoints, but does not implement the asynchronous endpoint correctly. Full support for asynchronous endpoints in usbaudio.sys is planned for Windows Vista.
I think I have explained this a long time ago. I believe this is legal speak for there might be a bug that makes this not 100% standards compliance.Depending on your computer and USB interface it works actually quite well.
Cheers
*** Depending on your computer and USB interface it works actually quite well. ***I would like so see some evidence of this, other than an assertion.
My understanding is the XP usbaudio.sys is a USB 1 audio class driver, and USB 1 does not support sampling rates higher than 48k.
Therefore, if a device works at 96k, it's probably not using that particular driver.
Things may be different if you also have the UAA driver loaded in your system. I believe UAA comes with an updated USB audio class driver which may well support additional features. But remember, this is NOT the original XP usbaudio.sys driver.
So basically what I would like to see is evidence that, on a computer without UAA loaded, you have attached a USB device, which can be shown to be using the usbaudio.sys driver (you should be able to show this using the Hardware Manager device properties), and you can show that it's operating in asynchronous mode, at 96kHz (I'm not sure how you can demonstrate this, but I'm all ears).
I don't mean to be intentionally skeptical, but I am finding it difficult to believe what you are saying.
I can check for the async mode since I don't have access to an 2NX right now but I am happy to plug-in my Optoplay for you right now.Works just as it has for many years. Shows up as USB audio device in the device manager and uses USBaudio.sys as the driver. When I play 24/96 material the data rate indicator on my DAC switches from 44 to 96.
The simple way to show which mode it is operating under is with a USB monitor. That is at least the way I used last time. In async mode you will find a second isochronous endpoint that is going from the sound card to the computer. This channel is being used to tell the computer how much data to send over the primary channel.
No need to get worked worked up about this I am just trying to help.Cheers
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That seems steep.
The $300 price difference is due to several new features relative to the DAC1.1. High-current output drivers. The balanced output drivers are designed to handle low impedance, high capacitance, and/or high-inductance loads without the THD+N suffering.
2. Auto-sleep mode. When no digital input is present for more then 15 sec, the unit will enter auto-sleep mode, and will re-awaken when the signal is present again, or when the front panel switch is engaged.
3. Option to mute output upon headphone insertion. This means the output will mute when you stick the headphone jack in. This option can be turned off or on, depending on your preference.
4. Two gain-range settings for headphone amplifier. This accomodates headphones of different impedances.
5. 96/24 capable native USB interface. This is not an off-the-shelf USB solution. This is unprecedented with regard to capability and scope. We spent significant amounts of time developing and tweaking this custom interface solution to gracefully handle high-resolution, native USB audio streaming.
Hope this helps!
Elias Gwinn
Engineer
Benchmark Media System, Inc
http://www.BenchmarkMedia.com
Why wouldn't you include this feature on the basic Dac1 as well? The USB soluion is nice but not particullarly practical for many applications. For example using a computer as a source for a high end audio system usually necessitates the use some kind of control interface such as a squeezebox (since the PC is often in another room to reduce noise). That said I'd only be interested in the basic Dac1 and am unhappy that it doesn't have high current drivers.
The DAC1 USB was designed to have several features which are not available with the DAC1. The high-current output drivers, the high-resolution native USB interface, auto-sleep mode, and new headphone operation features are all included into the price. These features are available to DAC1 USB users.Feel free to call or post with any more questions!!
Thanks,
Elias Gwinn
Electrical Engineer
Benchmark Media Systems, Inc
www.BenchmarkMedia.com
1-315-437-6300
$300 is a good investment if you:1/ compare to a DAC1 mod to give I2S interface
2/ compare to adding a USB/SPDIF interrface plus a good coaxial cable with the bonus of all kinds of problem associated with the USB/SPDIF (e.g. clicks and pops + not knowing whether it is truly bid perfect).
3/ compare to transporter in terms of the quality of sound you will get.
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