Andrew L Weekes
Reverse Engineer
Haven't posted for a while so this one might be of interest.
As most will be aware there's a plethora of DAC cards available for the Pi, but in terms of value for money, the original Wolfson (later Cirrus) DAC card has a lot of bang for your buck.
A 24/192 capable DAC, with ADC, built in stereo digital microphones, line in, line out and headphone drive capability, a 2W class D amp and some powerful internal DSP trickery.
Their biggest downside was they originally required a custom kernel and were less easy to implement than some of the simple DAC's. There were two versions of the board, the newer Cirrus board which was compatible with the Pi v3 is now obsolete and an older Wolfson card designed for Pi v1.
Matthias Reichl has written a new reworked driver for the Wolfson / Cirrus cards that doesn’t require out-of-tree patches to the upstream kernel modules. This means the card now works out of the box with Raspbian.
The best bit is the older Wolfson card (£18.76 on the Farnell site and >800 available from stock) which was only compatible with the older Pi's can now be made to work with a Pi3 and above!
There's a lengthy post on this on my website where I made a music player for my desk at work:
https://alw-audio.co.uk/?p=605
I also did some work on the reported sensitivity of the DAC to PSU noise:
https://alw-audio.co.uk/?p=643
Which I then looked to fix in a simple, cheap and elegant way:
https://alw-audio.co.uk/?p=657
I then discovered it wasn't performing at full resolution and discovered there's a noise gate enabled by default:
https://alw-audio.co.uk/?p=669
Then to finish it off, I did a new rear case that I 3D-printed:
https://alw-audio.co.uk/?p=680
As most will be aware there's a plethora of DAC cards available for the Pi, but in terms of value for money, the original Wolfson (later Cirrus) DAC card has a lot of bang for your buck.
A 24/192 capable DAC, with ADC, built in stereo digital microphones, line in, line out and headphone drive capability, a 2W class D amp and some powerful internal DSP trickery.
Their biggest downside was they originally required a custom kernel and were less easy to implement than some of the simple DAC's. There were two versions of the board, the newer Cirrus board which was compatible with the Pi v3 is now obsolete and an older Wolfson card designed for Pi v1.
Matthias Reichl has written a new reworked driver for the Wolfson / Cirrus cards that doesn’t require out-of-tree patches to the upstream kernel modules. This means the card now works out of the box with Raspbian.
The best bit is the older Wolfson card (£18.76 on the Farnell site and >800 available from stock) which was only compatible with the older Pi's can now be made to work with a Pi3 and above!
There's a lengthy post on this on my website where I made a music player for my desk at work:
https://alw-audio.co.uk/?p=605
I also did some work on the reported sensitivity of the DAC to PSU noise:
https://alw-audio.co.uk/?p=643
Which I then looked to fix in a simple, cheap and elegant way:
https://alw-audio.co.uk/?p=657
I then discovered it wasn't performing at full resolution and discovered there's a noise gate enabled by default:
https://alw-audio.co.uk/?p=669
Then to finish it off, I did a new rear case that I 3D-printed:
https://alw-audio.co.uk/?p=680