laptop multichannel ethernet OR PCMCIA sound cards

laptop multichannel ethernet OR PCMCIA sound cards

[Matt Flax]

We are after an ultra low latency connection to a multichannel in/out
sound card for a laptop. We want a portable system and don't want to
network to a different computer to achieve this goal.

As we are after ultra low latency, we are interested in both PCMCIA and
ethernet (gigabit) solutions.

Is anyone aware of any such ultra low latency hardware ?

Can anyone suggest any other solution for a laptop which is portable and
not based on ethernet or PCMCIA ?

I think that USB and firewire are good, but want even lower latency to
the hardware if possible.

thanks
-- 
Matt Flax, BE, BSc, PhD
Research Engineer

National Acoustic Laboratories
A Division of Australian Hearing

126 Greville Street
Chatswood NSW 2067 Australia
P +61 2 9412 6985
F +61 2 9411 8273

Please consider the environment before printing this email

Re: laptop multichannel ethernet OR PCMCIA sound cards

[James Courtier-Dutton]

2009/7/1 Matt Flax <flatmax@nal.gov.au>:
>
> We are after an ultra low latency connection to a multichannel in/out
> sound card for a laptop. We want a portable system and don't want to
> network to a different computer to achieve this goal.
>
How about any PCMCIA based sound card?
Latency is the same as a PCI based sound card.

Re: laptop multichannel ethernet OR PCMCIA sound cards

[Eliot Blennerhassett]

Matt Flax wrote:
> We are after an ultra low latency connection to a multichannel in/out
> sound card for a laptop. We want a portable system and don't want to
> network to a different computer to achieve this goal.
> 
> As we are after ultra low latency, we are interested in both PCMCIA and
> ethernet (gigabit) solutions.
> 
> Is anyone aware of any such ultra low latency hardware ?

Can you define what you require.

Do you want analog or digital audio I/O?

Do you need low latency in, out or both?

What samplerates do you need?

What latency would be acceptable (say how many milliseconds or 
microseconds).

regards

Eliot

Re: laptop multichannel ethernet OR PCMCIA sound cards

[flaxma]

HI, yes

A little more background ... we are implementing research algorithms for
hearing aids ... so ... we have many mic inputs and stereo output ...

we want a digital interface to the laptop.

Need 6 analog inputs
Need 2 analog outputs

Need minimal latency both in and out as it is a collect/process/output
system.

Sample rates anything between 22050 Hz and 48 kHz is good at this point.

At the moment we can get about 3 ms with an off the shelf firewire/usb card
 @ 48 kHz, however when we load the CPU with DSP algorithms, we sometimes
need to bump up the frame size and thus the latency goes up ...
We are running a realtime patched kernel.

I have found that there is about 2/3 of the latency in hardware buffers.

So we are still open to better USB/Firewire hardware, however would prefer
more bandwidth and hopefully less latency to the device. This is why I
asked about ethernet and possible PCMCIA.

Matt

> Matt Flax wrote:
>> We are after an ultra low latency connection to a multichannel in/out
>> sound card for a laptop. We want a portable system and don't want to
>> network to a different computer to achieve this goal.
>>
>> As we are after ultra low latency, we are interested in both PCMCIA and
>> ethernet (gigabit) solutions.
>>
>> Is anyone aware of any such ultra low latency hardware ?
>
> Can you define what you require.
>
> Do you want analog or digital audio I/O?
>
> Do you need low latency in, out or both?
>
> What samplerates do you need?
>
> What latency would be acceptable (say how many milliseconds or
> microseconds).
>
> regards
>
> Eliot
>
>
>
>

Re: laptop multichannel ethernet OR PCMCIA sound cards

[Florian Faber]

Matt,

> A little more background ... we are implementing research algorithms for
> hearing aids ... so ... we have many mic inputs and stereo output ...
> [..]
> So we are still open to better USB/Firewire hardware, however would prefer
> more bandwidth and hopefully less latency to the device. This is why I
> asked about ethernet and possible PCMCIA.

http://lad.linuxaudio.org/events/2009_cdm/Friday/07_Grimm/index.html

All these topics were covered in this lecture on this year's LAC, with
some measurements etc.


Flo
-- 
Machines can do the work, so people have time to think.
public key DA43FEF4          x-hkp://wwwkeys.eu.pgp.net

Re: laptop multichannel ethernet OR PCMCIA sound cards

[John Rigg]

On Wed, Jul 01, 2009 at 02:01:33PM +1000, Matt Flax wrote:
> 
> We are after an ultra low latency connection to a multichannel in/out
> sound card for a laptop. We want a portable system and don't want to
> network to a different computer to achieve this goal.
> 
> As we are after ultra low latency, we are interested in both PCMCIA and
> ethernet (gigabit) solutions.
> 
> Is anyone aware of any such ultra low latency hardware ?
> 
> Can anyone suggest any other solution for a laptop which is portable and
> not based on ethernet or PCMCIA ?
> 
> I think that USB and firewire are good, but want even lower latency to
> the hardware if possible.

Have you looked at the RME HDSPe MADIface?

John