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Re: Laptop sound cards

Hi all,

Like Ville, I have been using the VXPocket's AES/EBU output to an external D/A with good results, although not for final listening test  and have also heard very good things about the RME Digiface and Multiface referred to in other replies.

I have no personal experiences with USB soundcards but have read and heard from others that, even with the newer USB 2.0 there are some issues that have to be born in mind

USB shares multiple devices on a single IRQ so, unlike PCMCIA or PCI soundcards that have dedicated IRQs, depending on the number of devices attached and each ones bandwidth, there may be buffer under-runs if the audio output buffer size is not high enough and latency jitter depending on the access frequency of the devices.
Remedying these problems boils down to having only the most neccesary USB devices attached to the PC when using the soundcard and making sure that the output buffer size is large enough. Apogee also recommend that a USB soundcard not be connected to a hub and that the cable length not exceed 5 metres (although there are devices that extend the range of USB, e.g.ICRON Ranger, these are hubs and so should be avoided).


David Isherwood
Research Engineer
Audio Quality Assesment Group
Speech and Audio Systems Laboratory
P.O. Box 100, FIN-33721

> -----Original Message-----
> From: ext Ville Sivonen [mailto:vps@ACOUSTICS.AUC.DK]
> Sent: 04 June, 2003 18:37
> Subject: Re: Laptop sound cards
> Dear Satra and list,
> Digigram has a variety of sound cards for laptop.
> http://www.digigram.com/products/by_category.htm?o=getcat&pcat
> _key=PCSCD&t=Sound+Cards
> I have earlier used Digigram VXPocket v2 PCMCIA sound card with a
> laptop. The sound card was high quality, except at low sampling
> frequencies (<16kHz), when the noise floor was quite high for some
> reason. However, when using a higher sampling rate there were no
> problems.
> kind regards,
> Ville
> --
> ____________________________________
> Ville Sivonen, M.Sc.E.E.
> Sound Quality Research Assistant
> Department of Acoustics
> University of Aalborg
> Fredrik Bajers Vej 7 B 4
> DK-9220 Aalborg X
> tel. +45 96 35 8721
> fax. +45 98 15 2144
> email. vps@acoustics.auc.dk
> www.acoustics.dk
> www.soundquality.dk
> ____________________________________
> "Satrajit S. Ghosh" wrote:
> >
> > Dear list members,
> >
> > We are looking to get a sound card for a laptop. We would 
> appreciate any
> > suggestions.
> >
> > Thanks,
> >
> > Satra
> >
> > --
> > Satrajit S. Ghosh
> > Department of Cognitive and Neural Systems, Boston University