Dave, It's possible to skip the A/D conversion by using amplifiers with digital inputs. Texas Instruments have a 8 channels digital to PWM converter that can drive D-class amps with PWM inputs; that means only one A/D conversion, done by the speaker...
http://www.ti.com/product/TAS5508C Marc Wed, 25 Apr 2012 15:51:02 +0100, Dave Malham <dave.mal...@york.ac.uk> a écrit : > Hi Marc, > True, I'm sure you could use a usb interface, but even a low > cost multichannel unit would be quite a lot more expensive (and, > probably, power hungry) than the PI whereas Analog Devices (for > instance) do a 16 channel, 24 bit, 192kHz DASC IC for around 10 ukp > (ADAU1966) which would probably need around another 20 quid's worth > of op-amps and other bits to get going properly. Much more in the > maker tradition - and a possible product. > > Dave > > PS total number of pre-orders for PI's have reach 350,000! > PPS I'm not connected with them at all, I've not even ordered one! > > On 24/04/2012 18:33, Marc Lavallée wrote: > > The snd_bcm2835 driver is for the integrated stereo sound module. > > For more channels, a cheap 8 channels USB sound module would > > probably work, and ALSA drivers for many sound modules are stable. > > > > Martin Leese<martin.le...@stanfordalumni.org> a écrit : > > > >> Dave Malham<dave.mal...@york.ac.uk> wrote: > >> > >>> The Raspberry PI is really cheap and runs Linux, so it does > >>> provide some real possibilities, though > >>> it is, in some ways, quite limited - max 256m ram at present, for > >>> instance - > >> ... > >>> it seems that the SPI pins are available on a standard header so > >>> shouldn't be too difficult > >>> physically to add DAC's or ADC's (since most use that interface), > >>> though how easy it would be to > >>> write the drivers, I don't know. > >> The Arch Linux ARM image (operating system) > >> contains an ALSA driver. However, it states: > >> > >> "The alpha-quality ALSA driver included in this > >> release is disabled by default. Type > >> modprobe snd_bcm2835 > >> to enable it." > >> > >> Regards, > >> Martin _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
