As previewed on this site in November, the Wolfson Audio card for the Raspberry Pi is now available from Element 14. It has the following features:
- 3.5 mm jack (4-pole) for a headset/boom mic combination for gaming or VoIP applications
- 3.5 mm jack for microphone input
- On-board MEMS microphone
- 3.5 mm jack stereo line input for connection to devices such as digital audio players (iPod etc.) or mobile phones
- 3.5 mm jack stereo line output for connection to devices such as external stereo amplifiers or powered speakers
- S/PDIF input and output
- On-board class D power amplifier for external speakers, with connection to external power source if needed.
- Small pin header for extra functions if they are low cost, already on-chip, and don’t require any further components
- Raspberry Pi form factor
It’s currently available for £24, which isn’t at all bad for this quality of kit and is only compatible with Revision 2 Pis – the ones with the extra P5 pads. You don’t need to solder a header onto the pads as the card uses an ‘innovative sprung’ mechanism to connect to the pads. (I’m not sure what that looks like in practice, but it sounds like a very cool, and sensible, way of getting around the P5 header dilemma).
[…] recantha As previewed on this site in November, the Wolfson Audio card for the Raspberry Pi is now available […]
There is only one thing this board should do.
( DAC digital music stored on the pi and output via two good RCA sockets. )
We don’t want to feed other inferior sources into it, and we can use a “dumb” DAC to convert S/PDIF anyway, so why the need for the pi…..?
Lets face it, all we want is the pi to send our digital music through a good quality stereo DAC!
The Wolfson DAC, preferably two (one for left and right channel) to decode digital files stored on the pi up to 24bit, 192khz is the go.
Left and Right RCA is all that is needed, not a crappy, inferior 3.5mm stereo socket.
Buffer / boost the DAC signal to line level through one, or a couple good op-amps. Then send to an integrated amplifier.
Or better yet, in addition to the above give it a sub out and digital volume controls for all!
Then, make a car audio version to amplify right up to 5V for the line out.
Also for volume control don’t bit shift within the DAC to reduce output, the SN ratio goes down the toilet. Put a small pot in the feedback loop of the op-amp so as the signal decreases so does the noise, keeping a good SN ratio at all volume levels.
One better again, put a DCP in the feedback loop of the op-amp and still control the volume digitally while maintaining good SN ratio.
Then, sell me one.