Is USB overrated as decent digital source?

Some of the USB DACs or USB-SPDIF converters are really expensive, are they really worth the price?

Is USB overrated?

Lets discuss.

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I traded my fully modded Modwright 999es for an expensive USB converter. The converter/DAC outperformed the 999es on every level. I will never go back to a CDP. BTW, The Modwright was much more expensive than the converter plus a DAC.

Modwright $1500 to $2500. vs.
Converter $400 to $950 plus the price of the DAC of your choice. Mine total was $1100.
Expensive ? What about the Hagerman Technology HAGUSB for wopping total of $129?

That is the first one I would try to do the switch to USB digital.
I have an Ayre D1xe player over 10K, and I just bought a Wavelength Cosecant USB DAC a couple of months ago. The Cosecant is every bit as good as the Ayre and when you add in the benefits of having you music in itunes it's the clear winner.
I have been studying this for a few months and there are several approaches. Finished products such as Gordon Rankin's Wavelength products, less expensive but possibly as good stuff from Scott Nixon, or the kit approach. Google DDDAC for an example.

I am presently using a Scott Nixon USB DAC (modified by me by replacing the output caps with some I like much better and running it from a battery supply) and couldn't be happier with the results. My previous player was a Naim CDX-2 ($5,000) and I have no regrets.

I see no reason to get a converter to go from USB to spdif and then feed that to a conventional DAC as there are one box devices. Some use oversampling so that is something to consider. The Nixon DAC as well as others have basically 2 chips, the USB receiver fed to a DAC chip. Some also use a single chip, a USB receiver that also ouputs analog but all of these oversample so I personally would stay away.

I bought a Mac Mini as my server with storage on redundant firewire drives and it is a cheap (relatively) and very simple solution. I tried it on a Windows system but it becomes very complicated, the best ripper is a clunky third party program that is difficult to set up and use and the best players are even worse as well as having to use additional plug in programs to bypass the Windows kmixer digital handling that screws up the sound. The Apple Mini is simple and has a remote to control your music library
I have been considering the Mac Mini with either a Hagerman Chim or a Wavelength DAC. I have been wondering what you use for a screen with the Mac Mini and do you need a mouse and keyboard? I was hoping that, if it were to be used as a music server only, that it would be possible to get a very small flat screen and that only a mouse would be needed.
It comes without screen, keyboard, or mouse but just about anything will work. I bought a 19 in lcd at Compusa on sale for $199, an Apple keyboard and mouse. It will suppost a wireless bluetooth mouse and keyboard but I didn't see the need. When you boot up it it looks for both and won't go on until you plug them in, besides, you will want to edit file names and make playlists so you need a keyboard. You may want to go with a bigger screen as the mini comes with a great remote that you can use to control playback.
Hi Mike -

That's a tremendous thread you got going on AA.

Really not much to discuss except for the various value propositions offered by the manufacturers.

As Herman points out there is much to like about one box solutions but this is basically the same argument as CD players. If you have a great DAC already go the USB box with a SPDIF output to get started.

As Herman points out, these devices are based on stock chipsets being mass manufactured. What we are seeing - and are not really used to yet as audiophiles- is the impact of being able to use mass produced standardized products designed to sell to a worldwide market.

As the market settles, I don't think that products will have or manufacturers will be able to justify the kind of price spread we are used to in the rest of our space. One big reason is that there is no need to jump through the kinds of hoops it takes to make a great transport, turntable or speaker. (eg advanced metallurgy and manufacturing skills, sophisticated power supplies, furniture grade cabinetry with resonance and damping controls etc, etc) No analog physics here - not much EE - just IT

IMHO the three devices that have had the biggest impact on most people reading this forum (and Asylum PC where I also post regularly under xmasparty) are the Waveterminal ($155), the Squeezebox ($249) and the iPod ($350) The leading software - iTunes - is free.

Even without the tweaks being offered by the modders like Steve, Gordon, Wayne and Vinnie, we are already as close to as most of us are going to get (or will ever need to get) to a perfect source. We have some money in your pocket. And you can go back to fiddling with the rest of your rig.

Add a few hundred dollars for a better power supply or clock or connectors or caps and you have something better then most of us ever dreamed of.

As the big boys in the CE space start to do the math on iPod adoption I would expect more and more of them to being implementing strategies to get a piece of this pie...
Ok take for a moment that what your really asking is for some sort of Digital source to be changed to analog. Leave the USB out of it to begin with. USB is nothing more than a type of connection that will support a transfer rate of about 50MB a second. Are you interested in the dac, the connection, or how it gets interfaced with your source? All of them?

Then mass produced items get poor (generally) dacs the most expensive get the better dacs and better caps and better designs from the input (USB) to the output RCA.

IPODS do not output from USB they take input, they output analog which makes the ipod a non source. If you want to use the USB DAC from your computer then you place a whole additional piece in this puzzle as your computer must be fast enough to allow unbroken transmission to your DAC. This is easier said than done especially depending on the compression or non compression of your source and how the USB DAC supports the USB interface.

How does a winning combination sound? Better than most will admit, especially a audiophile, as we tend to hold on to the things we know, quite hard sometimes.
Mr. Stepenson, I'm not sure I follow. Are you saying that the computer with usb interface isn't fast enough?

I'm streaming uncompressed data from my Mini to my USB DAC and it works just fine. In fact it uses the older, slower USB1.1 as do all USB receivers designed for audio that I know of. USB 1.1 is more than fast enough to handle wav files.
Yes, USB1.1 has maximum 12Mb/sec bandwidth which is still fast enough to handle streaming music files even at 24bit resolution.
So, which external USB DAC have you decided on?
I sold my fully modded SB2 after 6 months a bought a CEC TL-1 transport for my EAD 7000 III DAC, couldnt be happier, the sound from the CEC is miles away better than the Modded Squeezebox2 into the DAC, the SB2 directly to amps did nothing...

I still have to try out the Wavelenght, but since I am using a passsive preamp the Brick wont do (so I hear) so I will need to splash ot some good cash....

I am afraid of cheaper options now, but I am listening, I have most of my CDs now on WAV files and I really love the availability of music through the computer.
USB is simply a method to get data from point A to point B. It has little to do with audio quality if the conversion circuitry is designed correctly. There are probably lots of poor designs out there, but this is true of almost every type of design, not just USB converters. USB has the advantage that the bandwidth is not limited as much as 802.11G (WIFI), so you can do 24/96 over USB and not WIFI. Also WIFI is limited in compatibility with player software. If you do AirPort Express, then you MUST use iTunes. If you do Squeezebox, then you MUST use Slimserver. There may be plug-ins that allow you to get around this though....

Steve N.
Empirical Audio
USB is underrated. I am using a Bel Canto DAC-3 with a USB port. It sounds just as good as a CD as long as you rip with a loseless format, like wma. The DAC-3 set on the USB input sounds better than any CD player I have used or heard, which has more to do with the master clock and TI dacs.
MikeChai - the difference in cost of USB converters is mostly due to four factors:

1) the inclusion of a low-jitter clock, such as Superclock4.
2) external power supply
3) custom software driver (not using the stock Windows driver)
4) optimum design and parts selection, regardless of cost

These four factors drive the cost up orders of magnitude, but also result in sound quality that matches or beats the best transports. It's like the difference between a Samsung $60 DVD player as a transport or an Esoteric.

Steve N.
Empirical Audio
I see alot of comments about the speed of USB but not enough about all of the pieces. You can certainly choke a PC or MAC with streaming music, as the Hard drive speed, Processor speed, amount of memory, and the USB version all combine. You must consider all of the parts that work in unison. USB has buffers at each end and performs error correction, no jitter that way. You must take into consideration all of the parts including the USB DAC when designing a music system based around a USB DAC and PC.
There are many misconceptions about USB audio.

The speed demands for streaming audio are so slow compared to the rest of the hardware that they have no problem keeping up. Even USB 1.1 is plenty fast enough.

USB for audio uses isochronous transfer and does not have any provisions for error correction. Even if it did error correction has nothing to do with jitter.
So are we saying that a .wav file is perfect as the information contained has been cross checked several times during ripping (eg better than streaming CD)?
Using a laptop connected via USB to a DAC such as the Audio Note 2.1, must be close to the perfect source???
The CDP manufacturers must be quaking in their boots.
I would much rather have a nice laptop as part of my system than an expensive spinner.
Yep Michael - you have figured it out - what's fascinating is to watch the massively time delayed reaction the industry seems to be taking. Here we are once again post RMAP and post CES and I have seen no coverage about any products that address this - meanwhile Apple blew all the projections out the doo - again - selling iPods. These are not big dots to connect....

Considering that the mid and hi-fi business has been on the ropes for years, if not decades, I find it remarkable that anyone in the 21st century is willing to sit around while their market share evaporates...

BTW IMHO the issue is not the multiple cross checks - its much simpler. Its simply much easier to pull data off a CD then it is to playback a CD in real time. Game over
You've got it Michael!

That's why I divested myself of an expensive single purpose device for a multiple purpose device -- MacBook. It and a Wavelength Ag Brick make beautiful music, much, MUCH more conveniently, and less expensively than my former CDP.
the difference in cost of USB converters is mostly due to four factors:

1) the inclusion of a low-jitter clock, such as Superclock4.
2) external power supply
3) custom software driver (not using the stock Windows driver)
4) optimum design and parts selection, regardless of cost

These four factors drive the cost up orders of magnitude, but also result in sound quality that matches or beats the best transports. It's like the difference between a Samsung $60 DVD player as a transport or an Esoteric.

Yah Steve. Agree with you. There's always a high cost if we want to squeeze the last drop of performance out of something. Out of the 4 points you listed, is No.1 the most costly?

As you said USB is merely a method to get data out of a computer, yet I think it's one of the greatest technology invented, for us computer audio freak. :D
Mikechai - No. 1 is the most costly, but well worth it, particularly the Superclock4.

BTW - I demonstrated my new I2S reclocker, the Pace Car at THE Show two weeks ago in Las Vegas. It's amazing how much of a difference it makes when the jitter is so low to be inaudible. Most audiophiles have no idea how much jitter they are listening to and how audible it is until its gone. This is the real flaw in real-time CD playback IMO.

Steve N.
There is a very nice professional product from TCelectronics, named Konnekt 24D (or 8D with less connection and DSP). It is a professional A/D, D/A converter mainly for musicians with Firewire connection.

They developed their own software driver for Mac and Windows, they have their own clock regeneration and jitter filtering and it can be used as a Firewire - SPDIF converter as well. This is how I am using it with a Macbook and an Altmann Attraction DAC (with all the clocking and jitter scrambling options). It sounds wonderful, with better dynamics, timing and transparency than any USB - to SPDIF converter I tried. The Altmann Attraction DAC / Konnekt 24D / Macbook is an extremely musical and emotional combination, I changed an Accuphase DP-100/DC-101 system to this one, and never looked back. Since I am using this system I almost doubled the number of my CDs, and I had more than 1000 earlier.
I'll check out the TCelectronics.

What are the USB to SPDIF converter that you have tried?
The Konnekt24D is powered from the firewire cable, which is the computers power. Have you changed this to battery or external power?

I have no experience with firewire converters, but the others in this industry say that the firewire chips are very jittery compared to the USB chips. Have you opened it up to see what firewire chip they are using?
Audioengr, the Konnekt can be firewire bus powered or externally powered by 12V DC.

I have read the brochure and the features. It has anti-jitter technology called DICE II and the JETâ„¢ technology.

Clock and Jitter
Internal/External Sample Rates

44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz and 192 kHz / 43 to 193 kHz, jitter rejection at all rates
Jitter Rejection Engine
- JETâ„¢ technology in TC DICE II

Jitter Rejection Filter
<-3 dB @ 10 Hz, < -100 dB @ 600 Hz

DIO Interface Jitter
< 1 ns peak, BW: 700 Hz to 100 kHz

AD/DA Conversion Jitter
< 42 ps RMS, BW: 100 Hz to 40 kHz

Digital Output Phase
(stand alone and across network)
< 0.5 % of sample period

Digital IO interface jitter of < 1ns? That's very low...
I am using a JVC 5.1 receiver model rx-9010vbk. This particular receiver is equipped with a mini-USB port on the front panel. This port connects to the USB port on the computer, allowing to use the computer as the playback source. I have a G-4 Mac and use I-tune's exclusively to play my 19000 mpg's through my stereo system. This is done with the JVC receiver via usb port to usb port on computer. The receiver has Burr-Brown PCM 2702 DAC and my computer automatically recognizes it. I use to connect my receiver to computer with rca inputs, but USB is much,much better since the sound quality and fidelity is noticeably better since I am bypassing the internal sound from the computer by going usb direct from the receiver. I have done some research and have found there very few is any current model receivers that have usb port for connecting computer for mgp playback.

FYI, the soon-to-be-shipping Musical Fidelity
"X-DACv8 Tubed Digital-to-Analogue Converter"
has USB connectivity ...
FWIW i am using a external dac made by M-Audio called "firewire audiophile." I like it because it is a great stand alone dac for my G4 cube and it has coaxial digital outputs. Sounds great as is, but down the road i will probably add an external dac to furtehr enhance the sound.

Just thought i would let everyone know that there are other solutions for fast data transfer besides USB.

Dont know if firewire is any cleaner, but i know its faster.

Firewire was designed from the ground up with music and sound in mind.

You implicitly raise an interesting point. Considering Firewire and USB, what are the relative strengths/weaknesses of each for computer music servers and is one better for these applications?
I am very satisfied with the Slimdevices Transporter. It is the only device that I know of that will output AES/EBU and it also has a word clock input. The DAC is outstanding and probably every bit as good as my Audio Aero Capitole. Having said that, I still run it through my Audio Aero into my main listening room The Transporter's DAC is a bit too analytical for me. I run the analog feed from the Transporter into the next room.

The Transporter is connected to my Computer using RJ45 even though it has full wireless capacity. It works very well with my G5 itunes, to the point that I have not played a CD in quite a while. Also, I can search for streaming audio over the entire world by type, region, style of music, etc.

Listening to some of the African Nations has been fun. Check it out! - anywhere near 1 nsec is high jitter in my book. For instance, the stock Squeezebox and AirPort Express have 300-400 psec, which is half what you are saying and I can easily hear the jitter.

Until you have heard really low jitter, you dont know what you have been listening to all these years...

Steve N.
Empirical Audio
Firewire and USB are similar in performance. The advantage of USB is there are more drivers and better chips available that support it.

Steve N.
Empirical Audio
Unclejeff - It's a shame to spend $2K and just use the S/PDIF output. You would be better off to drive your DAC with I2S IMO. It's inherently superior and lower jitter.

you have to study the Konnekt brochure a bit more carefully. The 1 ns jitter is for the complete A/D, D/D and D/A loop. They developed their own firewire software driver for mac and pc, the mentioned Dice II and Jet chips developed for jitter attenuation and stable and jitterless clock. It has a 12V 2A external power supply.

I am using a Konnekt 24D since last december with my Altmann DAC. In the last 2 and half years I tried dozens of different USB, USB2 and Firewire to SPDIF converters with coax and with Toslink outputs. None of them were working so well (for me at least, YMMV) as the Konnekt with my latest Macbook. I sold my Accuphase DP-100/DC-101 when I became familiar with the Macbook - based solutions. Never looked back. The only CD player which is in the same league was the Naim CD555. Nothing else.

Since last week-end I am using the Altmann Creation ADC as an SPDIF clock generator for the Konnekt, it is now externally synchronized to the battery driven ADC and its Ultra Precise Clock. Soon I will be using the Konnekt from the same battery as the ADC. Can not imagine more pleasure from my cds and high - res audio files.

You can find a picture of my system here:

and here:

It is one of my friends' system with a custom built CD Pro transport using a spruce board from Charles Altmann:
Audioengr; You make a good point. Also, your inputs over at That Other Forum is really appreciated. For now I am using the Transporter digital output for two reasons. First, on my main system I prefer the warmer signal going to my amps that comes from the Audio Aero, as opposed to the more analytical sound I get from the Transporter. Also, the Audio Aero allows me to seamless switch audio sources without adding an awkward switching device. My Audio Aero accepts Toslink from the Satellite Receiver which also doubles as a decent OTA High Definition Receiver, and I use my Audio Aero's coax input for DVD and the AES/EBU input from the Transporter that also pulls music from my computer as well as streaming audio. Then, of course there is the occasional CD I play on the Audio Aero Capitole itself.

I am using the Transporter's analog output to another room that has a very nice secondary music distribution system which includes the Audio Aero Capitole amp.

The folks at slimdevices tell me that, for my purposes, the squeezebox that was given to me by them(when the Transporter was back-ordered) will suffice as, by bypassing the DAC I am not gaining any more by upgrading to the Transporter. However, I disagree as whatever happens when the Transporter it used sounds better.
Ferenc--Wow! I just clicked on your system. I have never seen anything like it. I am sure it sounds great---still, with all of those cables, etc. it looks a little bit like a BORG (ala Star Trek) Transport Device.


Actually the transport is not mine but one of my freinds' transport.
It seems that the venerable Benchmark DAC has been upgraded to include a USB port. Has anybody head this one?

Bel Canto DAC 3, USB from a Mac, is exquisite --
compared to my $2500 CD player ( brand withheld
in respect ). Apple Lossless, or uncompressed AIFF,
either, USB to a DAC like the Bel Canto 3 ... Best of
everything: no more shiny discs, iTunes interface --
which is not perfect yet, but, sure beats flipping discs.

Throw a couple of Bel Canto monoblocs
in the mix, and I haven't heard better except for maybe
the $30k + Linn activ set-up at my dealer. Maybe that set-up
was better ... but I'm not at all sure that it was.
I actually auditioned the Bel Canto DAC 3 prior to auditioning the Brick and was not as impressed, and the price was really high for the sound. It sounded stale in my system. The DAC chip they use in there (TI) is largely a commodity chip and in my system I could hear the difference between it and a few other DAC's I auditioned. Most notably the Wavelength Brick was just second to none of the DAC's I auditioned. Incredible detail and very musical, and hand-made piece as well.