[aragon63]

This one is worth mentioning ....... and it's on its way .

  Valab WM8741 24bit 192k USB DAC - Dual WM8741

   $ 330 + $ 50 shipping

   http://www.ebay.com/itm/Valab-WM8741-24bit-192k-USB-DAC-Dual-WM8741-Balanced-XLR-Output-Silver-Face-/280907938626?pt=US_CD_Players_Recorders&hash=item41676afb42

[wushuliu]

This one is worth mentioning ....... and it's on its way .

  Valab WM8741 24bit 192k USB DAC - Dual WM8741

   $ 330 + $ 50 shipping

   http://www.ebay.com/itm/Valab-WM8741-24bit-192k-USB-DAC-Dual-WM8741-Balanced-XLR-Output-Silver-Face-/280907938626?pt=US_CD_Players_Recorders&hash=item41676afb42

Interesting. Though you can also get the Audio-gd NFB 3 for the same money with discrete output (no opamps) and much beefier power supply. No xlr or optical out though.

[OzarkTom]

Check this out at RMAF in Avatar Acoustics room. With hadphone amp and preamp, it is rumored to be less than $400 and the sound of a tube Dac. It is made by AMR audio.

The iFi iDAC instantly transforms your computer audio into a 24bit/192kHz audiophile-grade
music source. 24bit/192kHz music has 6.5x more resolution than normal CD.
ESS Sabre® Hyperstream® DAC, one of the most advanced DAC chips, is at the core of the
iDAC allowing it to execute ‘Bit-Perfect’ High-Defi nition audio.
Asynchronous USB transfer with ZeroJitter Lite® technology and an with an internal master
clock, lock out all jitter coming from the computer clock.
Directdrive® technology get rids of the need for coupling capacitors, delivering a very high
damping factor with undistorted, uncoloured sound through all headphones.
WHAT COMPUTER AUDIO HAS BEEN WAITING FOR
iDAC
24/192KHz HD USB DAC

For Mac OSX this equiment can be plugged in directly.
For MS Windows, please install the driver software from the iFi website BEFORE connecting this equipment to the computer.
Specifi cations
• Compatible with High-Speed USB 2.0 (24Bit/192khz)
• Input Voltage: AC 100 - 240V, 50/60Hz
• Power (max.): 2.5W
• Dimensions: 156(l) x 68(w) x 28(h) mm
• Weight: 200g (0.5 lbs)

[geowak]

I have the Schiit Bifrost and it is very good. Although I did not do "technical" type testing. I did compare it to my Benchmark USB DAC1 and it sounding about 80 to 90% as good. So as one poster noted, it can hold it's own.

It is very neutral and very clean in it's presentation of the music. I don't use it as a USB device. I use it via Toslink.

IMHO

[ltr317]

I have the Schiit Bifrost and it is very good. Although I did not do "technical" type testing. I did compare it to my Benchmark USB DAC1 and it sounding about 80 to 90% as good. So as one poster noted, it can hold it's own.

It is very neutral and very clean in it's presentation of the music. I don't use it as a USB device. I use it via Toslink.

IMHO

What do you like about the Benchmark over the Bifrost?  Thanks.

[DaveC113]

I have the Schiit Bifrost and it is very good. Although I did not do "technical" type testing. I did compare it to my Benchmark USB DAC1 and it sounding about 80 to 90% as good. So as one poster noted, it can hold it's own.

It is very neutral and very clean in it's presentation of the music. I don't use it as a USB device. I use it via Toslink.

IMHO

I'm happy with my Bifrost as well. I might go for the high end model coming out soon... not the Gungnir but the next one, it's supposed to be their top end DAC for around $1500.

[aragon63]

  For $199 you can get Calyx Audio - Coffee USB dac (ESS Technology ES9023 chip ) / line level preamp with volume control & mini- plug headphone jack.

 

 Overview

[geowak]

What do you like about the Benchmark over the Bifrost?  Thanks.

Well to answer this question..(don't want to get off topic, maybe this will be helpful?)
The Benchmark USB DAC1 that I have has the USB as standard. The Bifrost has it as an option, but I did not get it. The Benchmark can also be used as a headphone amp, and really a very good one indeed. The Bifrost does not have a headphone option. Also, the Benchmark has a variable gain knob and allows for fixed gain. The Bifrost does not have that. So in many ways the Benchmark is more versatile.

Also the Benchmark is slightly better in resolution. It also is a bit smoother across the freq band. These sonic qualities are very marginal and mostly I hear them through the headphones. Both are very musical. Maybe the Bifrost is better here, the Benchmark is more clinical sounding. YMMV.

I could live with each one very well, and can recommend either one without hesitation.

[OzarkTom]

This is from the Enjoy the Music website of 2012 RMAF coverage, fourth picture down. AMR IDac/Pre/Class A headphone amp for $299.


http://www.enjoythemusic.com/rmaf_2012/sunday/

[Letitroll98]

This is from the Enjoy the Music website of 2012 RMAF coverage, fourth picture down. AMR IDac/Pre/Class A headphone amp for $299.


http://www.enjoythemusic.com/rmaf_2012/sunday/

Here's a slightly more complete report, and I mean slightly, from a London show.

http://www.theaudiobeat.com/nas2012/nas2012_ifi.htm

[OzarkTom]

Here's a slightly more complete report, and I mean slightly, from a London show.

http://www.theaudiobeat.com/nas2012/nas2012_ifi.htm

Thank you for that site. That IUSB for about $150 is said to clean up even the highest priced USB DAC's that are in use today. AMR says it even improves their $5K DAC.

[TheChairGuy]

I see this topic began months ago....a year is like an eternity in the DAC business and there are at least a couple new entries to consider...

AudioEngine D1: 24bit bit depth, USB and Optical (digital) inputs, volume control, 1/8" headphone AND rca outs....$169.00: http://audioengineusa.com/Store/Audioengine-D1#.UHyS91HZ0VA

Audioquest Dragonfly USB: 24 bit depth, USB only, 1/8" output only, internal volume control, thumb drive sized....$249.00: http://www.audioquest.com/usb_digital_analog_converter/dragonfly-dac

I wanted to hear the famed ESS Sabre chip in action and I loved the extremely small size (for traveling) so I just bought the AQ Dragonfly last week and I'm evaluating it now.

[emac]

Should also add the Ross Martin Audio PCM1794A DAC.  Recently took my modded Maverick Audio TubeMagic D1 out of my computer system and put the RMA DAC back in.  Really enjoying the speed, detail, and microdynamics. 

Gotta admit, I'm interested in trying the Dragonfly out.  Might pick it up for my wife, who uses headphones at work.

[techguy]

I recently also just acquired the Audioquest Dragonfly USB as described above and have had it a couple of days now.   I'm blown away at how good it sounds for the money.   It is an Async design that supports incoming stream up to 24/96 and the unit does not up-sample (which I prefer).

I previously had an HRT Streamer II+ and this Audioquest unit beats it easily for quality and accuracy.    While the Dragonfly can be used with both headphones and an integrated amp, I'm using it in my home office feeding a Creek Integrated amp and this combination seems to work well.   Only downside is that you need to use an adapter for phone jack to RCA output.

Best settings are to leave your computer volume setting at maximum to avoid using its analog volume control.   Also if using a Windows platform, use the Wasapi output add-on that bypasses all Windows audio processing including volume control.  I combine this with Foobar2000 as my music platform.

Only downside is that is doesn't natively support 24/192 bitstreams.   

While it won't replace my Bryston DAC anytime soon, this is a great deal at $ 250.   

[OzarkTom]

Check this out at RMAF in Avatar Acoustics room. With hadphone amp and preamp, it is rumored to be less than $400 and the sound of a tube Dac. It is made by AMR audio.

The iFi iDAC instantly transforms your computer audio into a 24bit/192kHz audiophile-grade
music source. 24bit/192kHz music has 6.5x more resolution than normal CD.
ESS Sabre® Hyperstream® DAC, one of the most advanced DAC chips, is at the core of the
iDAC allowing it to execute ‘Bit-Perfect’ High-Defi nition audio.
Asynchronous USB transfer with ZeroJitter Lite® technology and an with an internal master
clock, lock out all jitter coming from the computer clock.
Directdrive® technology get rids of the need for coupling capacitors, delivering a very high
damping factor with undistorted, uncoloured sound through all headphones.
WHAT COMPUTER AUDIO HAS BEEN WAITING FOR
iDAC
24/192KHz HD USB DAC

For Mac OSX this equiment can be plugged in directly.
For MS Windows, please install the driver software from the iFi website BEFORE connecting this equipment to the computer.
Specifi cations
• Compatible with High-Speed USB 2.0 (24Bit/192khz)
• Input Voltage: AC 100 - 240V, 50/60Hz
• Power (max.): 2.5W
• Dimensions: 156(l) x 68(w) x 28(h) mm
• Weight: 200g (0.5 lbs)

Here is IFI's new website

.http://www.ifi-audio.com/en/

[wisnon]

Yes Tom,

I think the iDac and iUSB Power (retail $500 for the combo) will be a killer solution besting stuff all the way up to say the $2500 range. I think the combo will soon be discovered  to be an INCREDIBLE value proposition.
People need to take a serious look, because this stuff is chock full of innovative tech. This could well be what many have been looking for....

Just on the iUSB, I got nice insight from the designer...


Why a USB Power Supply?

by iFi Audio on Thursday, November 1, 2012 at 11:43am ·
We get asked this a lot. Why would anyone need this Box?
It is simple. USB carries audio AND power. Many USB Audio devices power at least some part, often all of the Audio Device from the power supplied by the Computer via its USB Port. The power supply from USB Ports on PC’s is variable in quality, but always contaminated by noise. Have a look here comparing the noise from the best (lowest noise) USB Port on a PC optimised for audio idling… When playing music this is worse.
This is a lot of noise! Many common Laptops and PC’s put out tens of millivolts of noise. That is as much noise as you often get music signal and much more noise than the delicate, small details and nuances in a musical performance. Another issue is the presence of a ground connection between the Computer and the USB Audio device. This can create earth/ground loops that even if they produce no audible hum or buzz, sound quality can be impaired.
So it is little surprise that computer based audio often fails to live up to the expected and possible excellent sound quality.So why do manufacturers keep relying on USB Bus Power? Cost plays a role, as does portability and practical considerations.
Adding the iUSBPower USB Power supply and breaking the ground loop using the IsoEarth gives a major improvement in clarity, detail and musicality. Any audio device starts with the power it receives and with the iUSBPower USB Power supply your USB Audio device gets power so pure, it has even lower noise than a battery!
But the true secret weapon is the ability to break ground loops. We have measured an improvement of over 10 times even in system that are already optimised and have no audible noise.
Like ·  · Share

>>>>This is a Critical part of ANY highend USB based music server!
November 4 at 4:38pm · Like · 1

>>>>> is the power supply galvanic isolated, pardon my ignorance.
November 6 at 10:01am · Like

iFi Audio Not sure in which way you mean this? In order to keep compatibility with high speed USB2 (480MBps) to allow multi-channel use at high sample rates/resolution we cannot employ USB isolators. All current isolators are limited to 12MBPS or 2 Channels at 96KHz, which we felt was not acceptable for modern audio. So we cannot fully, galvanically isolate the DAC and PC.

However, full isolation is not strictly needed. USB Signalling is differential, so in theory only the two signal lines are required. In practice we need somehow a ground reference. If this ground reference comes only through the USB cable, all is well.

If there additional path through other equipment and mains wiring things become problematic.

So our "IsoEarth" feature allows breaking the ground connection in a way that is reliably safe for attached equipment (sorry to be vague, but we consider the precise method a "trade secret") and does not require "earth lift" or "cheater" plugs.

As we also interrupt the power line from the computer and substitute our own super regulated very low noise supply from the Computers power we essentially only leave the two USB signal lines active and connecting between PC and DAC is IsoEarth is engaged.

I have measured differences in of around ten times (20dB) with IsoEarth engaged in systems we use for testing - that is they are already quite well treated regarding the ground noise problem!

When testing a USB Isolator marketed for Audio in the same setup I observed similar gains in ground noise levels as with the iUSBPower, suggesting that in our system at least breaking the ground line and full isolation perform comparable, objectively. I did observe that the 5V output from the USB Isolator was quite noisy due the use of an isolating DC-DC converter, which basically a small switched mode supply.

Sorry for the lengthy missive, but it is not a simple subject.
November 6 at 10:29am · Like

>>>>>  how does this device actulaly work? I am not sure how it is to be used. It is not a USB-Spdif converter, so what actually is it? How would it be used with such a converter? Is the iUSB powered by a SMPS?
Wednesday at 12:20am · Edited · Like

>>>>> Is there a manual online?
Wednesday at 12:17am · Like

iFi Audio ,

First, you can find more details and manuals etc. On-Line.

Secondly,the iUSBPower plugs into the USB connection between the PC/Mac and any USB Audio Device. Some of the more extreme High End gear does not draw power from the USB, the vast majority of USB Audio Devices, including USB to SPDIF Converters do.

In recent times we have seen some attempts to for example split up USB Cables and Lithium Polymer batteries to substitute the power supply, however most batteries when actually supplying are quite noisy (see our AP2 measurement which includes a 9V Dry Cell, rechargables are worse).

The iUSBPower contains noise filtering using multiple LCR filters and a so-called super regulator (as opposed to a simple cheap 3-pin regulator) which is similar but not identical to the one described by Walt Jung under this name.

As a result you isolate the USB Audio Device (including USB to SPDIF converters) from the computers power supply and you give a power supply much cleaner than that from the Computer.

Additionally we have also build in some ground impedance management and the option to break the USB ground connection entirely. This can help a lot with noise loops.

Third, you ask is it powered by an SMPS, plugtop type which we supply, however any source of around 9V DC may be applied (at your own risk, mind you). As we wanted a simple way of being able to sell and use the iFi worldwide and we wanted to avoid wasting power, we had to use a custom low noise SMPS.

In basic principle an SMPS is a much better choice power supply than using 50/60Hz rectified. The high frequency at which they produce their AC means transformers can be small and thus minimise noise leakage from the mains, they always use choke input filtering and the high frequency means relatively small components are required to filter any noise.

Another factor, such a supply may be made universal (runs on any mains voltage/frequency current, even DC) and if well designed efficiency will be very high, well over 90%.

However, many common inexpensive examples are build so badly they barely pass FCC requirements. This means they radiate a lot of noise back into the mains and often have very large levels of noise on the output.

The first examples we bought straight in shops like Radio-shack were horrendous. The noise on both the mains input side and the output side was sufficiently high to be visible easily on cheap oscilloscopes. output ripple went from 10's to 100's of millivolt.

Opening them up revealed that the RF filtering was not fitted, that the chokes and capacitors where of insufficient value and that several parts that would have produced low noise where missing, even though there where spaces provisioned on the PCB to fit them.

So we worked with a factory to produce our own plug-top power supply, which not only has all the extra parts fitted but goes beyond this. The result is a power supply that leaks very little noise into the mains (you can measure it, but it needs an expensive analyser, scope traces are clean).

Overall, a common linear supply using a transformer, common rectifiers and a 3-Pin regulator will produce more noise (including noise radiated into the mains) than our SMPS. Do not expect most SMPS's to perform similarly.

Finally, why don't you just try it? Ask our US distributor for a loan unit.
Wednesday at 4:43am · Like

>>>>> Thanks for the detailed and thorough explanation. I can now see more clearly the benefits and I do agree that a properly made SMPS is actually an advantage.
Yesterday at 7:33am · Edited · Like

[shadowlight]

Emotiva XDA2 for $399 on sale for 349 right now - shipping on 11/26 according to Emotiva's website.

[JohnR]

All current isolators are limited to 12MBPS or 2 Channels at 96KHz,

That's a good point, they all (well a few at least) seem to use the Adum4160 which only runs up to 12 MBPs.

[OzarkTom]

Great post wisnon. Since AMR insists the IUSB even makes their $5K Dac  sound better, $199 add on sounds like a great deal. I hope to give it a try soon.

[wisnon]

Did you know that stocks are exhausted till late next week? I got the last and it was the demo unit. LoL

Delivery early next week. I dont think they expected he instant demand, but as I say, power accessories are going to become the new rage in the coming years as the iPod crowd matures and steps up from MP3 to lossless.

I have not heard them yet, but from talks I had and studying the tech, the iDac+power combo will be a KILLER. It will discombobulate the market at the current price-point. Hold on tight.

We may have to rename this cheap and exhilerating!