First Steps into Computer Audio

"good ol' Ethernet may be the dark horse"

Ethernet has beat out every other technically superior network protocol in the world because... it's dirt cheap to implement. For world markets it's not so much about building a better mousetrap as building a mousetrap that's good enough and doesn't cost very much.

With so many different versions of the Windows operating system it's cumbersome for small manufacturers to implement the software drivers needed for firewire. I'm not saying one is better or worse than the other, but simply that USB is the dominant format for consumer computers, so if you want to sell audio interfaces, you'd better target the USB market. BTW, the PFO article is a great piece with lots of info.

I'm sure that's a factor, but several of the respondents in that PFO piece argue that there are other reasons why USB is the better choice, including some technical reasons. Regardless, it appears that good ol' Ethernet may be the dark horse in this race.

Historically, Firewire was the dominant format in pro audio equipment. When pro audio went personal computer based the Apple Macintosh/Digidesign ProTools was the dominate platform, and Firewire became the interface of choice. Since pro audio applications required working with far more than 2 channels of audio at a time, Firewire's speed advantage over USB was important. The current prevalence of USB interfaces for home computers isn't a reflection of any technical advantage, but due to the fact that the overwhelming majority of home computers are non-Macintosh and don't come equipped with Firewire ports.

PS - here are the individual answers

http://www.positive-feedback.com/Issue41/ca_moore.htm

Thnx - very interesting read. You've got a little of everything and a lot of no one really knows - would love the chance to read the raw responses as well.

Thanks - I didn't even notice that. EXCELLENT information from various perspectives. For Cerrot, here is the take from the initial question about interfaces posed to Steve Nugent of Empirical. This also goes directly to the question of USB vs Firewire:

The only interface of those listed that can have Async protocol, or handshake with flow-control is USB. Firewire does not support it and neither does AES/EBU or S/PDIF, coax or Toslink. Async protocol allows the master clock to be located at the designation device, either a converter, reclocker or the DAC itself, which is the optimum scenario. This establishes the master clock near the D/A conversion and then controls the source rate using a flow-control protocol.

However many USB and all Firewire interfaces do not use flow-control. The jitter characteristics with these is only as good as the circuits/chips that track the incoming stream from the computer. The master clock is established at the source, which is the computer, and then this must be maintained by all circuits up to the D/A conversion. The jitter from the computer must be dealt with by using PLL-type devices (Phase-Locked-Loop). These track the incoming datastream and synchronize to it, as the same time using filtering and other clever tricks to reduce the jitter of the original stream. Fortunately, there are a few very good chips available that deal with jitter very effectively, namely the DiceII chip for Firewire and the TAS1020 for USB. Even though these do not establish the master clock for the system and instead track the computer datastream clock, their jitter rejection is excellent. Current support for samples rates is: USB - 24/96, Firewire - 24/192 and S/PDIF - 24/192. Look for this to change in 2009.

Of the interfaces listed, an important one was omitted, and that is networked, otherwise known as LAN, Ethernet or Wi-Fi wireless network. The protocol of this network has inherent in it the flow-control and retry mechanisms that enable the optimum audio streaming scenario, as well as having the advantage of avoiding altogether the sometimes troublesome audio software stack of the computer OS. Using networked devices, either wired or wireless can be no different than sending data to a printer. The only concern is getting the data to the device intact. There is no timing information sent or implied. The data is not contiguously streamed at real-time speed as with USB, Firewire or S/PDIF interfaces. It is packetized and sent periodically in high-speed bursts over the network, whenever the network has an "opening". These packets are then collected in a buffer memory at the destination device where they can be clocked out to the D/A using a local low-jitter master clock. The fact that networked data flow incorporates flow-control and retry, and bypasses the computer audio stack makes it the superior method. The only disadvantage is that the player that interfaces to the network is currently a custom player, such as Squeezecenter or Sonos. Hopefully, in the future Microsoft and/or Apple will create more generic player software to drive a networked interface so that more player options will be available. As for bandwidth, networked interfaces can not only support the highest audio sample-rates, such as 24/192, but it can support multiple channels of this, allowing for multiple channel playback for software generated speaker crossover and even movie surround-sound.

The index of all of the interviews is here

Thanks again for pointing that out, Drubin.

Yeah, he asked that same series of questions of several (many!) digital gurus. Great stuff, and they were the right questions as far as I'm concerned.

Thanks for the link, Drubin...that's an interesting read. Also, Ckorody for the computer interface history.

These comments from Charles Hansen of Ayre are a pretty strong refutation of the Firewire point of view.

Guys - just for history. Apple introduced FW400 - it was very cool at the time since we were living in the bad old days of SCSI.

But the WinTel world (remember that) didn't like it (OK they hated it) because they had to pay a royalty for each computer equipped with FW.

So they backed USB. And pretty soon USB was ubiquitous and FW a niche product. Remember we are talking a global market here which is what put USB over the top. I suspect there are a 1,000 USB machines for every FW machine and that might be conservative.

Later USB 1.1 begat 2.0 and soon there will be a 3.0. There are also five iterations of FW by now.

As long as we are using RedBook and 24/96; speed is not an issue - the audio files are very small, while cache, RAM and busses are very fast. To be sure an old PC which is asked to do some other processor intensive tasks at the same time or whose HD is an overloaded nasty mess may have some trouble keeping up. Same for a 386 PC that is being asked to upsample. This is one of those fascinating things that the bit biters like to bring up over and over but one never finds a concrete example of... YMMV

FWIW the general consensus seems to be that while we can agree that FW is a much better format then USB for some things, the war is long over and FW is and will remain a niche product.

Consider that many of the newer Apple Notebooks like the MacBook, the MacBook Air and the Mac Mini don't come with FW. No argument that its a way to control costs - but it reflects the fact that no one uses it.

There is a reason that Steve, Gordon and most everyone else designs for USB - it's what people use. Which is why that is most likely where the innovations will occur. And is most certainly the choices are.

Cerrot - I guess I'm missing your logic here. Though I can understand that firewire delivers more information, faster than USB 1.1 (I'm pretty sure most USB DACs are using the older version), if it's delivering the info to a buffer where it is then passed on and reclocked by the DAC, how is delivering it any faster going to make the music sound better? Perhaps I'm missing something, and if so, somebody 'splain it to me. If a grocery store needs a steady supply of three cases of Spam every day it won't matter much if it's delivered every morning by a man in a delivery truck or two race car drivers in a Ferarri - the Spam still arrives each morning in time to be sold. The Ferarri may be a better vehicle to get the Spam to the store faster, but what's the point if the truck can get the same Spam there every morning as well? If firewire is a better interface for DACs then why are some of the best PC DACs using USB?I'd be interested to hear from someone like Steve Nugent who actually designs this stuff and makes that decision.

I'm not sure, Reubent. My issues aren't with the DAC, just the architecture of the PC interface. I'm sure it sounds great. My only thought would be that using firewire out, the PC would perform better. If the PC performs better, I would think all would sound better as well.

Again, historically, USB was never intended to passthrough audio, just attach peripherals. I'm not sure why PC audio adopted USB as it did. I predict that within two years, all will be using firewire.

Cerrot,

Do the new asyncronous USB DACs like Wavelength and UltraFi overcome the USB issues you mention? I've heard the new UltraFi MusicStream DAC connected directly to a Mac Mini via USB and it was outstanding.

Enjoy,

TIC

http://www.sweetwater.com/expert-center/techtips/d--03/26/2002

http://www.usb-ware.com/firewire-vs-usb.htm

Above are just two links I had from recent searches. I had spent a bit of time on this before I went with firewire. I understand most of the PC audio offerings out there are USB-and I'm not a Mac guy but, again, technology wise, Firewire is, well, better. I'm sure all your USB systems sound wonderful, and I have heard quite a few USB systems that sound great. I tried a few different USB set ups (utrends to spdif; benchmark dac w/usb) and, even with a pretty highpower PC, 10,000 rpm hard drives, I had some hiccups w/usb and sound stage was not as wide or deep, and have better resolution and retrieval of low level detail, and system is MUCH more transparent with the Firewire. Before you dismiss is, give it a try. I have tried both.

Drubin, it is an undisputed fact that the firewire interface is superior to usb by all computer techs. As I have said, just google it. I don't recall anything specific to dacs, just the interface. Please do a search and you will see what I mean. I am not knocking USB-most here are using it. All I am saying is that firewire, tech wise, is better.

The easier, less expensive way to go is getting a firewire to spdif converter. MAudio has the firewire solo for $200-you can get any dac you choose. Aside from streaming & packets, USB uses up CPU cycles, so a 480 usb throughput is actually slower than Firewire 400.

Sorry, Jax, I haven't checked this thread. I'll see if I can find something and post it.

$80 ?

I don’t think you’re actually stepping up over the CL card that way.

I think cost is an issue for you for now. If so, and it is for me too now and then, I'd go with as good a firewire or USB (outboard) PC soundcard for now. I have one of those CL cards too.

M audio cards do sound better. No question.
Going out of the card into the exact same DAC, with a different interface (coax) than USB, you will gain more accuracy and depth... or I should say in my case, that's what happened… as I could set the software to emulate upsampling to 24/96 or 24/192.

Also, down the road you can take more time to get a good to great DAC, which will definitely be an improvement.

You’ll also have a fall back unit just in case.

Look at the M audio 24/192 outboard card… About $200… Sam Ash carries them as do many others. I go to Ash ‘cause they’re close by and flexible when you show them cash. Their online outlet is right here in my town, but sometimes they’ll differ on price from their BM stores, so check out both, if possible…

J R music also caries them. Both are price competitive. Both are good places to buy from in my exp.

I think from everything I have read a USB DAC is the best way to go, I have the option to get an EMU 1820 (not M) for around $80, and wondering if thats ok till I get a good DAC. Thinking I can sell it easily for $80.

S

Drubin

Agreed.

I'm in no mood, nor hurry to make changes in the HDD digital pile up going on around here.

I'm still experimenting in fact... I'm also receeding from living on the bleeding edge tech wise too.

maybe on the next gear-go-round I'll look into another way to do things. right now I am very well pleased.

Yes, the iRoc is a great deal used. It was about $1500 new.

And Jax2, thanks for the invitation. I will take you up on it if the opportunity presents.

All I said is that cheap USB sucks, but obviously mileage varies. The iRoc is not cheap USB. And I may need to back off my earlier comments a bit after last night, when I was very impressed with the USB input on the Bryston DAC.

Sorry I didn't get your gist - I thought you were making a broader critical statement than that. At the $550 you sold the iRoc for it seems pretty affordable to me, but I guess that's all relative. Cool beans on the Bryston results. Their CD player got a good review in the recent TAS fwiw.

All I said is that cheap USB sucks, but obviously mileage varies. The iRoc is not cheap USB. And I may need to back off my earlier comments a bit after last night, when I was very impressed with the USB input on the Bryston DAC.

I keep hearing folks allude to fire wire, & I2S. i DON'T SEE MUCH BY WAY OF AFFORDABLE PATHS THERE THOUGH. i2s, ESPECIALLY. a $1,000 for the gizmo needed to get the info to a I2S DAC? Then there's the I2S DAC costs. how much is a decent one of those going for lately?

Blindjim - if you're happy with your current DAC/rig there's no reason to change. But to answer your question, certainly at the $2k cost of your BC there are I2S options. I think Red Wine's Isabellina is $2500. Northstar, Perpetual Technology and Audio Alchemy all have I2S DACs. Empirical Audio also modifies some DACs, like the Benchmark, for I2S input. You can read an interesting article by Steve Nugent of Empirical which contains much information on USB and I2S in Positive Feedback, here. Like you, I've had pretty good results with USB. I've only seen very expensive firewire options out there. I've yet to read anyone else opine that Firewire is a superior interface for PC audio purposes, and am still awaiting some links from Cerrot to support that statement.

Tok20000

Please tell me how you rip 16/44.1 CDs to a 24/96 format?

or anyone else for that matter.

et al... I'm not so sure the inference that USB sucks is either truthful, or appropriate.

I say this only becuase what I'm getting via a USB DAC sounds better than what I was getting from my CDP via the same DAC using coax.

There are indeed other factors aside from just the interface, I suspect.

I keep hearing folks allude to fire wire, & I2S. i DON'T SEE MUCH BY WAY OF AFFORDABLE PATHS THERE THOUGH. i2s, ESPECIALLY. a $1,000 for the gizmo needed to get the info to a I2S DAC? Then there's the I2S DAC costs. how much is a decent one of those going for lately?

I'm pretty well pleased with my BC DAC3. Either way... coax or USB. Even it's optical interface isn't bad. I spent some hours last night using just that link and had a very good time with it using my mega changer as a source. So in essence I was using a $300 CDP, the BC DAC3, a $10 fiber optics cable, some HT Magic II rca LINKS OFF OF IT TO AN ONKYO 805, then out via Audio Art ICS to Dodd mono blocks & sonata IIIs & Velodyne DD15.

No getting around it, it was fun. Fun to me is being able to listen without the idea popping up 'something isn't right here', for extended periods. When I can just keep playing till the wee hours of the night, I'd say I'm enjoying what I'm getting.

.... using the laptop via USB into that same deal is noticeably better.

... better too is using my preamp and better ICs & pcs.

.... better still is using this last path with J river MC, and the Vista 32 laptop on it's DC power supply sitting atop a small Ebony folding table.

...yet one more level up is using this USB driver:

http://www.usb-audio.com/download.html

$70.

Ripping with error control is yet another step up.

ALAC, AIF, WAV, all sound very good to excellent, depending on the orig recording of course. Even compressed AAC files sound at least decent.... only the mp3 files were noticeably poorer sounding... (many of which were seven or eight years old too and done at 320kps constant bit rates).

I'm hard pressed to believe USB sucks IMO.

the pc path I use not counting wires came to me at $2750. $750 of which (the laptop) was free. So $2K for the DAC and 1TB NAS drive.

M Audio does issue a Fire wire sound card duplicate of the Audiophile 192... which I own in PCI format. I believe it's under $300 or right at it. I wasn't aware of that when I bought the PCI version... BTW, their support is great.

Check "M" out. ;-))

As far as budget would like to stay in the $300 range or under for DAC and our sound card if not USB DAC.

S

For the last several months I have been reading this Forum as well as a number of other PC audio forums. I could be wrong, but the consensus seems to be that the best PC to DAC connections are as follows (in descending order);
1. I2S
2. Firewire
3. USB ala something on the order of Empirical, Wavelenght, Weiss, et. al.
4. USB into an affordable DAC
5. coax or optical from internal soundcard to DAC

But, there are other considerations. Downloading one of the free media players, like Foobar, Media Monkey or JRiver Jukebox. And for Windows XP, downloading the free ASIO4ALL driver to avoid the Windows KMixer.

So each of those four DACs you've tried left you with a strong preference for a standalone player, and not liking USB DACs in general (I'm not sure I'm interpreting you correctly in that - forgive me if not)? Of those you noted I've only heard the Benchmark, which, as I mentioned, I did not like (found the highs ever strident - but same via a transport), so I could understand your not liking it. I've also heard the Bel Canto, though not in my system. The Bel Canto sounded great in the TAD room at RMAF '07 fwiw and to my ears, and again at CES recently in the Bel Canto room. I've not heard the other two. You sure seem to have liked the Ultra-fi iRoc USB DAC. From your ad:

Honestly, I would call it the most musical component I can remember owning -- by which I mean that it extracts the musical line in a compelling fashion from everything you play.

If you're ever up in the Seattle area you'd be most welcome to come over and hear the TP in my modest system. Ping me through A'gon for my contact info.

I hear what you are saying, but my experience has been disappointing and I've tried quite a few things. I'd love to hear your "Modwright Transporter I use (via wireless, NOT usb) without any doubt at all exceeds any transport I've used." I've tried the USB input on the Bel Canto DAC3 and Toslink out to a Benchmark, an Audio note and a Lavry. Will try the USB on the Bryston this weekend.

However, inexpensive USB audio sucks, in my experience. If you have a good system, products like the Keces, HagUsb, and the USB input on many otherwise good DACs are complete non-starters compared to playing a CD via a transport.

I tried the HAGUSB briefly and did not like it at all. That was many years ago - Perhaps they've improved it. The USB input on the MHDT DAC was good in my system and would easily compete with many of the standalone players I've owned. I would not consider it expensive at around $600 new. The current Modwright Transporter I use (via wireless, NOT usb) without any doubt at all exceeds any transport I've used via wireless connection to my music library two floors below in my basement. Using a transport into the DAC of the Modwright Transporter it is marginally better. Disclaimer: Modwright is one of my clients. The Benchmark USB DAC, though I ultimately did not like it for the same reasons I didn't like it via a transport, did not give up much via USB. I've heard the same USB Benchmark in a few rooms at both RMAF, CES and THE Show sounding quite good (contrary to my own experiments with it). Red Wine Audio's Isabellina DAC was sounding great via USB. Maybe I'm misinterpreting your intent, but it seems like it's a broad and sweeping statement you've made for having studied for "several months". Does that mean you've tried out many different USB DACs - if so, which ones? I guess I'd say my impressions are different (obviously) and I've been using computer audio for several years rather than months (and did not always favor it). I would agree that some of the cheap USB devices have the potential to be poor performers as does any cheaply built/designed component. No surprises there. I think the potential of PC Audio in general could easily exceed the performance of a CD transport. Check out the recent article on the high-rez formats and the Berkley Alpha DAC - I think in TAS...maybe January...or was it Decemeber? I'd suggest you give it a better chance as there is great potential there.

I've been studying computer audio intensively for several months and have found nothing to substantiate Cerrot's claims. Respectfully, I think you are wrong, buddy.

However, inexpensive USB audio sucks, in my experience. If you have a good system, products like the Keces, HagUsb, and the USB input on many otherwise good DACs are complete non-starters compared to playing a CD via a transport.

Cerrot - thanks for explaining that a bit. I did a search but could not come up with much at all. Would you point out some URL's that expand more on this as applied to DACs? As I understand it USB is much easier to implement than Firewire and certainly most offerings in audio DACs and servers use USB. The ones that implement Firewire are usually much more expensive, like the DCS gear (which wouldn't be my inclination to recommend to someone stepping up from a card in their computer). Do you know of any reasonably priced Firewire DACs? Wavelength DACs are now using an asynchronous USB technology, but they do suggest using a Firewire hard drive to store your music library on. Empirical's offerings are all USB. Those are certainly two of the more respected computer-audio offerings in the high-end. I've listened to many USB DACs that do an outstanding job, packets or not. Certainly from the standpoint of what they sound like, I cannot hear any reason to dismiss USB on face value as a DAC interface. The computer audio solutions I've tried have all sounded equally as good, if not better than the best standalone player I've listened to and owned. None have used Firewire.

USB does not stream, it transmits packets. That's the problem. USB was created in order to connect peripherials, ie printers, scanners, etc. Firewire, on the other hand, was created for audio. There is quite a bit of info on the net explaining the differences and advantages of firewire (even against USB 2.0). Here on 'gon, the majority are using USB, but please take a google, and you will see some major audio concerns explain that USB is an inferior interface for high end audio applications.

Tok2000 - I haven't seen your posts here in ages! My friend has been working with Steve on getting his PaceCar and Northstar modified DAC to work out for him. His been mightily impressed by the Pacecar in demo. Seems like beyond the budget of what the poster is talking about, but de-jitter is certainly a good idea. There's also Genesis Digital Lens, and Monarchy's solutions, which are more frequently on the used market at reasonable prices. Don't know how they might compare.

USB is for printers?! Can you elaborate on that comment? I don't know that it's as much a matter of of the computer side interface since even USB 1.1 is plenty fast to stream music, but I think the DAC side makes a more significant difference. Those solutions like Empirical's, which go straight to I2S rather than convert from S/PDIF would be the direction I'd go. Again, you'd be breaking what I only anticipate might be your budget, but another good choice might be Red Wine Audio's Isabellina DAC (USB>I2S). I heard that NOS DAC at CES recently and it sounded great! Just a stream of thoughts....

Fire Wire.
USB is for printers.

I have been into computer audio for over 6 years.
It all depends how much you want to spend.
If you want serious killer sound, get Empirical Audio's Off Ramp Turbo. This device makes all the sound of the computer come out of USB and it reclocks all of it removing most of the jitter and outputs it through a short RCA cable, so you can use any DAC with it. I would recommend getting a DAC that can process 24/96 as this setup will allow you to output 24/96 (which sounds freakin amazing) through the USB port. The Off Ramp Turbo runs $1k new, but it is worth every penny. They do pop up for less here occasionally.

Keith

you can also look at the USB Dac from Blue Circle called the Thingee, sound very good for 160.00.
Greg

go outside of the PC tower with your card at least.

Past that a better driver for it will help. many USB sound cards will also have updates on their websites even though you just bought the thing new... so do look there too if you go USB sound card.

Past that... an independant USB DAC/Sound card driver like the german version sold for $70 or so will really help too.

A DAC with USB if money permits is also a thought.

In any case... DAC or Card... the better, the better. Apogee & Lavry make some nice units for under a grand with lots of flexibility and fine support.

Two all-in-one amps with built-in DAC's that you could consider are the Nuforce Icon and the Peachtree Decco. I have both and think they're wonderful products for the money.

There are two versions of the Quad 11L speakers. One is a traditioanal small monitor/bookshelf speaker and one is an active version with built-in amplification.....

TIC

I was mistaken about the Quad 11L - it is indeed self-powered. I was thinking of the old 11L which was no active.

Hi Shriram.

> The Quads are not active (self amplified) speakers like the Audioegines. You would need a preamp plus amp or an integrated amp to run the Quads.

> IMHO, the digital to audio converrsion should take place outside of the PC where, like Jax2 wrote, its too noisy.

> If you are running WMP (Windows Media Player) you should download a better sounding player (for free)like JRiver Jukebox, Media Monkey or Fubar.

> If your OS is Windows XP, you should download (free, again) ASIO4ALL which will improve sound by bypassing the Windows kernel mixer.

> The speakers and the electrics depend on you budget. USB DACs(most of which also have optical and/or coaxial inputs)start at about $150 and run to over $5000. AGon always has a good assortment of used DACs up for sale. If you give your budget, I'm sure a number of Forum members will make good recommendations for products in your price range.

I'm also researching computer audio and came across this site:

http://www.computeraudiophile.com/

which has lots of reviews and recommendations. Probably not the last word, but lots of good stuff to read through.

Over the years I've probably built 10 computers buying all my parts from NewEgg. So I did some research on sound cars there. When I searched the category and sorted by highest rated here is what I found:

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2000290057&bop=And&Order=RATING

HT-OMEGA is far and away the highest rated with SB not even showing up until like 10th place. Now, I've never heard or heard of HT-OMEGA, but I read the reviews and people love this company's audio cards. And many of the reviews are clearly audiophiles.

Anyway, hope my research helps you. Good topic and I'm looking forward to seeing it progress.

Definitely agree with Jax2 - do not do your audio in a computer unless you are prepared to spend for a very, very good sound card - not worth it IMHO

I favor USB - very standard, nothing too exotic is required in the cable - get a Belkin Gold.

I am delighted with the Valab sold on ebay for $180 shipped to your from Taiwan - for the price and much more its a giant killer. The Keces units are also excellent. No argument about the Paradisea btw.

BUT you will not be able to feed the speakers from the DAC unless they are active (contain their own amplifiers). Sorry I am not familiar with the ones you mentioned. Generally speaking you will need an amp - I suggest an integrated with the preamp built in.

The other alternative which I have not researched are the amps with a built in USB DAC. While not the ultimate, I like these kinds of solutions for several reasons:

1) they work as a unit - no messing with matching

2) it is compact which in a room your size is a significant consideration

3) fewer boxes means fewer interconnect and power cables which add up fast

Let us know how it turns out

You might want to see if you can find a pair of AVI ADM 9.1 speakers; they're a 2 way monitor from England that's very popular over there among those using a computer for source. They are an active speaker with built in pre-amp, power amps and 24/196 DAC. Very nice sounding, and perfect for computer audio. We're dealers for it up in Canada, sells for 2K USD. Well worth looking for.

Get the DAC out of the noisy electronic environment of the computer....definitely will make an improvement. I don't know what your budget is, but based on what you've done so far I'll hazard a guess and recommend an MHDT Labs Paradisea DAC..You can probably find a used one for under $500. Their Havana DAC is even better, I'm told, but quite a bit more expensive and more difficult to find used.