Is there a maximum playback rate to PsychPortAudio?

1
Dear all,

I'm planning to playback ultrasonic sounds (up to 32kHz) as part of my research, and I was wondering if PsychPortAudio was suited for this.

Using the GetDevices function, I can get some information on the specifications of the different audio devices under windows 7. However, the minimum and maximum sampling rate of all my audio devices are both always returned as 44.1kHz, while I am pretty sure that they support both lower and slightly higher (48kHz, DVD audio) sampling rates. This got me wondering whether it is PsychPortAudio itself which presents a ceiling to the allowed audio playback rates.

Specifically, I want to playback audio sampled at a rate of 192 kHz, and am wondering whether this is possible using the latest PsychToolBox version and a dedicated soundcard (I'm thinking of the M-Audio Audiophile 192).

I could not find anything about this on the forum or wiki, and since this information would also influence choices made on the rest of my setup, I really hope you could give me an answer; I'd be very grateful.

Thanks in advance,
Paul



--
This conversation is incomplete. You can help by expanding it.
2
There's no printout of our driver which would tell you minimum and maximum sampling rate. It only tells you the default sampling rate, recommended for standard use. That's probably the 44.1kHz you see.

The driver supports up to 200kHz and has been tested with rates of 44100, 48000, ... up to 192000 Hz. The 200 kHz limit is just to catch typos, as i'm not aware of any sound card that goes beyond 192 kHz.

So if your sound card and driver supports it, it should work for you.
On Windows you should get an ASIO capable sound card.

A different question would be if the 192 KhZ (or 96 kHz net signal if we take the Nyquist sampling frequency into account) would reach the speakers. It is likely that standard sound cards have built in low pass filters which cut off the signal at a much lower frequency. That's something you might wanna check.

best,
-mario

--- In psychtoolbox@yahoogroups.com, Paul Mertens <pecmertens@...> wrote:
>
> Dear all,
>
> I'm planning to playback ultrasonic sounds (up to 32kHz) as part of my
> research, and I was wondering if PsychPortAudio was suited for this.
>
> Using the GetDevices function, I can get some information on the
> specifications of the different audio devices under windows 7. However, the
> minimum and maximum sampling rate of all my audio devices are both always
> returned as 44.1kHz, while I am pretty sure that they support both lower
> and slightly higher (48kHz, DVD audio) sampling rates. This got me
> wondering whether it is PsychPortAudio itself which presents a ceiling to
> the allowed audio playback rates.
>
> Specifically, I want to playback audio sampled at a rate of 192 kHz, and am
> wondering whether this is possible using the latest PsychToolBox version
> and a dedicated soundcard (I'm thinking of the M-Audio Audiophile 192).
>
> I could not find anything about this on the forum or wiki, and since this
> information would also influence choices made on the rest of my setup, I
> really hope you could give me an answer; I'd be very grateful.
>
> Thanks in advance,
> Paul
>
>
>
> --
> This conversation is incomplete. You can help by expanding it.
>
3
the big question is can your entire signal chain faithfully reproduce signals up to 32 kHz??? it's easy to mathematically create a stimulus like that, presenting it is another matter entirely...

what kind of signals are you presenting?


--- In psychtoolbox@yahoogroups.com, "Mario" <mario.kleiner@...> wrote:
>
>
>
> There's no printout of our driver which would tell you minimum and maximum sampling rate. It only tells you the default sampling rate, recommended for standard use. That's probably the 44.1kHz you see.
>
> The driver supports up to 200kHz and has been tested with rates of 44100, 48000, ... up to 192000 Hz. The 200 kHz limit is just to catch typos, as i'm not aware of any sound card that goes beyond 192 kHz.
>
> So if your sound card and driver supports it, it should work for you.
> On Windows you should get an ASIO capable sound card.
>
> A different question would be if the 192 KhZ (or 96 kHz net signal if we take the Nyquist sampling frequency into account) would reach the speakers. It is likely that standard sound cards have built in low pass filters which cut off the signal at a much lower frequency. That's something you might wanna check.
>
> best,
> -mario
>
> --- In psychtoolbox@yahoogroups.com, Paul Mertens <pecmertens@> wrote:
> >
> > Dear all,
> >
> > I'm planning to playback ultrasonic sounds (up to 32kHz) as part of my
> > research, and I was wondering if PsychPortAudio was suited for this.
> >
> > Using the GetDevices function, I can get some information on the
> > specifications of the different audio devices under windows 7. However, the
> > minimum and maximum sampling rate of all my audio devices are both always
> > returned as 44.1kHz, while I am pretty sure that they support both lower
> > and slightly higher (48kHz, DVD audio) sampling rates. This got me
> > wondering whether it is PsychPortAudio itself which presents a ceiling to
> > the allowed audio playback rates.
> >
> > Specifically, I want to playback audio sampled at a rate of 192 kHz, and am
> > wondering whether this is possible using the latest PsychToolBox version
> > and a dedicated soundcard (I'm thinking of the M-Audio Audiophile 192).
> >
> > I could not find anything about this on the forum or wiki, and since this
> > information would also influence choices made on the rest of my setup, I
> > really hope you could give me an answer; I'd be very grateful.
> >
> > Thanks in advance,
> > Paul
> >
> >
> >
> > --
> > This conversation is incomplete. You can help by expanding it.
> >
>