My problem with firewire is the cables and connectors. Especially the
connector which is easily dislodged, not a good thing when recording
audio. As Bob Olhsson mentioned, the build quality of cables is generally
poor. Both firewire and USB are capable of isochronous data transfer so
there is no reason why firewire should perform better. However Firewire is
peer-to-peer whereas USB requires the host to arbitrate traffic and since
USB will also have input devices (mouse and keyboard) attached, I suppose
it's possible that this could interfere with streaming audio. But if you
do the math, both Firewire and USB should be able to handle over 80
channels of 96-24 audio input/output, so there should be enough overhead
to fit a couple of mouse clicks in-between the audio stream. (For the
record real-world transfer rates are about about 25-30% below the stated

In general I feel it is a bad idea to have AD conversion in the computer -
it is full of EM interference and clock chatter. Try this experiment: take
a piece of 24 gauge wire and wrap a half dozen tight loops ~1" diameter in
the middle. Solder the ends to pin 1 & 2 of an XLR and plug it into a mic
input of a mixer, crank up the gain and hold the loops next to your
computer - all that crap you hear is also being picked up by your ADC. An
outboard unit will be better shielded and isolated.

Konrad Strauss 
Director of Recording Arts, Professor of Music
Indiana University Jacobs School of Music

On 8/10/11 8:16 AM, "Tom Fine" <[log in to unmask]> wrote:

Hi Konrad:

Thanks for the information and clarification.

So your preferred system is an internal AES/EBU card and do all the ADC
and DAC through external
units not integrated with the computer, so the computer is more a "record
and playback head" than a
full-fledged "tape machine"? I've thought about going this way with my
next DAW, not using the
computer for any analog interface, either way, but using it as a storage,
processing and editing
system all in the digital world.

What is it about Firewire cables and connectors that you find to be
"dodgy"? I thought Firewire was
the more reliable interface for constant-stream data like digital audio
and video, that USB was
designed more for bursts of data like moving files between hard drives or
emptying photos off a
camera or sending a document to a printer.

-- Tom Fine

----- Original Message -----
From: "Konrad Strauss" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, August 09, 2011 9:30 PM
Subject: Re: [ARSCLIST] digital input sound card recommendation

> +1 on the Lynx cards. We have six AES16 that have been in service for
> years now. As with all computer systems they require tweaking from time
> time as the OS is updated, but I've found maintenance to be pretty
> straight-forward.
> To answer a couple of Tom's points below, jitter is not a issue in
> digital-to-digital data flow. This is called interface jitter, and as
> as the samples arrive at their destination intact no harm is done. (The
> other kind of jitter is called sampling jitter, it happens during ADC and
> can cause major problems) So Firewire and USB interfaces are not
> necessarily bad, it really depends on the implementation. Personally, I
> dislike the cables and connectors, especially Firewire. The whole system
> seems dodgy to me. You can also run into problems if you want to use
> Firewire/USB DAC and ADC units from different manufacturers, often this
> impossible because of incompatible drivers. I much prefer to stick with
> AES.
> The interaction between audio and video subsystems is probably caused by
> an IRQ conflics. My memory is a little hazy since I haven't had to deal
> with this for a few years, but occasionally PCI slots will share the same
> IRQ address so if the audio and video card are in slots that share,
> glitches can be put into the audio stream when minimizing windows or a
> monitor going to sleep. Usually the recommendation is that if this
> try swapping PCI slots. I think that in Windows 7 you can manually assign
> IRQ addresses but like I said I haven't had to deal with this for a while
> so I may be misremembering.
> -- 
> Konrad Strauss
> Director of Recording Arts, Professor of Music
> Indiana University Jacobs School of Music
> On 8/9/11 1:46 PM, "Tom Fine" <[log in to unmask]> wrote:
> Hi David:
> That's a real bummer. Those are my front-line ADC's too.
> There has been much progress in recent years with external ADC's.
> I keep reading articles
> and papers about the USB connection not being ideal due to jitter and
> latency issues. And yet,
> firewire keeps getting de-emphasized by hardware manufacturers. I'm also
> not sure what role video
> circuitry plays in a modern Windows system. Even thru XP, there was some
> interaction between digital
> audio and the video subsystem, I'm not expert enough to discuss details
> but there are articles and
> white papers out there.
> If you're doing your analog-to-digital conversion externally and then
> "recording" an AES/EBU stream,
> it seems like you could use a very simple interface, but again I'm not
> sure how much clocking and
> latency matter in that setup.
> I've had some CardDeluxe cards since 1999 and they still work fine. Why
> not just recycle them as you
> upgrade computers, or are you building out more workstations and now need
> a new way to skin the cat?
> -- Tom Fine
> ----- Original Message -----
> From: "David Seubert" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, August 09, 2011 1:38 PM
> Subject: [ARSCLIST] digital input sound card recommendation
>> This discussion has come up repeatedly over the years but I just learned
>>that the Digital Audio
>> Labs CardDelux has been discontinued. I'm not sure why they have been
>>discontinued, but we got a
>> call from the manufacturer who said that they are "obsolete." We have
>>long used their cards (we
>> are a PC shop) and I need to spec out another PC-based audio
>>workstation. I use the CardDelux for
>> the AES/EBU digital inputs.
>> What are people using for digital input from an external ADC these days?
>>Is there an equivalent
>> sound card to the DAL card with AES/EBU digital inputs? I know some ADCs
>>offer firewire/USB
>> outputs, but I haven't really explored that.
>> Please send any suggestions to me on or off list.
>> David Seubert