USB soundcard for measurements?

[John Sheerin]

I'm looking for a new sound card to do 2 channel measurements with using a laptop. I previously had a laptop that had a PCMCIA slot which I bought a nice Echo Indigo IO card for. Unfortunately I no longer have that computer and the two laptops I currently have either don't have a PCMCIA slot or are internally crippled so the Indigo feeds back.

So now I am looking for a USB soundcard. I need something that has a line in and line out and is full duplex (can play and record at the same time). I also need something that I can disable internal feedback on. In other words, I need to prevent the input from being fed to the output. I'm looking at the Creative X-fi 5.1 for $60:

http://www.newegg.com/Product/Produc...82E16829102020

However, I've never seen a set of soundcard specifications that lists these two qualities that are important to me. So that's why I'm asking here - does anyone have an X-Fi and have you used it to take 2 channel measurements with successfully? Or does anyone have any other recommendations around this price range?

Thanks,
John

[Helmuth]

Hobby box users say the creative x-fi is good.


I use a USB behringer UCA202 16 bit 29,- euro
And with toslink.
And no aditional mixer software

[cbrunhaver]

Hi John,

I use an M-Audio Transit USB with my Praxis rig with good results (it is one of their recommended cards), though the Praxis "audpod" has it's own mic pre. The only negative is that their Vista driver support is spotty.

If you're looking for something with phantom power, you might consider the M-Audio Mobile Pre USB. I've use this with an EASEra setup with good results.

-Chris

[Thawach]

[/B][/QUOTE]

Helmuth,29 euro its very cheap but when it comes to thailand. its very expensive(around 85 euro) diy in thailand thiks a lot when theywill buy.

[dlneubec]

I've had good luck with the Edirol Ua-1EX, a 24bit/96khz USB Audio interface.
Edirol Ua-1EX

[gainphile]

I use Creative Soundblaster Live!.

You get 24/96kHz DAC with that, and only $50 !

Sounds great too.

[mcmahon48]

http://cgi.ebay.com/ESI-U24XL-24-bit...3A1%7C294%3A50

I did a lot of research in finding out what would give the most accurate result and this one came out to be the best gives the best of both worlds inexpensive with truly flat accurate readings
I was going to use my creative Audigy nx, but I am waiting to get one of these before doing any testing

[John Sheerin]

Thanks guys. I'm going to try the Behringer.

[Helmuth]

The behringer isn't the best one when you look at the snr, for loudspeaker measurements more than good enough.

There are very good products like terratec. snr 110dB

terratec

[John Sheerin]

I've been using the Behringer more, and my conclusion is it sucks. The signal to noise ratio, specifically the 1/f noise, makes it almost unusable for measurements at low frequencies in my system. There is so much noise I can't measure impedance at low frequencies accurately - the noise is making the impedance rise at low frequencies. I know I could get around this in various ways, but basically I don't want to and don't think I should have to. I've never had to before with other soundcards. I was measuring a speaker outside today as well, and with my mic (Linkwitz modded Panasonic capsule) around 5m away and mic my preamp gain all the way down,I couldn't get above the noise floor at 20hz without clipping the input of the sound card. Once again, I could get around that by building more attenuation into my mic pre, but it should not be necessary. Besides, I was already cranking on the woofers and didn't really want to go any louder. I was afraid my neighbors were about to start complaining.

I must say in the Behringer's favor, it was truly plug and play on my laptop running WinXP and it was cheap, but that's about the end of its advantages.

So now I'll try something else that's been previously suggested in this thread - just not sure what yet.