how to use 24-bits sound card to do data acquisition?

[linnarlee]

my boss ask me use a 24-bits sound card to do data acquisition,the frequence is more the 90KHz,but i find the LV6.1 only can do less 16-bits and 44KHZ.so how can i do ,some one tell me the LV7 can do the 24-bits,is it?and can you introduce me some example for this?

[Randy_H]

LabVIEW 7 Express does not have 24-bit sound VIs either. You can do some data acquisition with them, but that is not what they were designed for. I would suggest a true data acquisition card. NI sells many that can do that rate of speed, but not at that rate. Whay are 24 bits needed? Will 16 do? If so, then NI sells many boards that will meet your needs.

Sound cards were ment to work in specific ranges and the way LabVIEW interacts with them is through the Windows kernel, so there will be many timing and buffering issues that will be very difficult to get around. I strongly suggest buying a dedicated data acquisition card.

Randy Hoskin
Applications Engineer
National Instruments
http://www.ni.com/ask

[Greg_McKaskle2]

> my boss ask me use a 24-bits sound card to do data acquisition,the
> frequence is more the 90KHz,but i find the LV6.1 only can do less
> 16-bits and 44KHZ.so how can i do ,some one tell me the LV7 can do the
> 24-bits,is it?and can you introduce me some example for this?

LV will work fine with these. The existing sound VIs in the palettes
will not. If you know what DLL functions to call to do the acquisition,
then you can make quick wrapper VIs around them and you are off. The
existing sound VIs do exactly this, and they handle most sound card
tasks, but obviously not the high end.

Greg McKaskle

[urs boegli]

Randy,

I would like state that the main difference is that soundcards are not
able to to handle dc components of any signal and so many measurement
methods are just not possible.
Another big diiference is the prize. I doubt NI can supply us with a
16bit card for 20$ 😉

I would like to observe the amplitude of an ac signal with a fixed
frequency.
Is there a vi that can be used to read in an 'endless' stream of
'audio' data?

Urs

Randy H schrieb:

>LabVIEW 7 Express does not have 24-bit sound VIs either. You can do
>some data acquisition with them, but that is not what they were
>designed for. I would suggest a true data acquisition card. NI sells
>many that can do that rate of speed, but not at that rate. Whay are 24
>bits needed? Will 16 do?
If so, then NI sells many boards that will
>meet your needs.
>
>Sound cards were ment to work in specific ranges and the way LabVIEW
>interacts with them is through the Windows kernel, so there will be
>many timing and buffering issues that will be very difficult to get
>around. I strongly suggest buying a dedicated data acquisition card.
>
>Randy Hoskin
>Applications Engineer
>National Instruments
>http://www.ni.com/ask
>
>

[qBot]

The same stuff ! We've got some 24bit 192kHz sound cards that are just fine for some ac measurements...

Does LabView 8.0 support 24bit sound ? Or the only way is to use the low-level (edit a so_config.vi or something like that)?