Category Archives: Information

A HiFiBerry DAC installation using a linear power supply

Here comes another nice HiFiBerry DAC installation. Jens from Germany doesn’t like switching mode power supplies for audio. Therefore he created a HiFiBerry setup with a huge linear power supply. Note that the power supply needs to provide at least 5V/1A for a stable operation of the Raspberry Pi. Depending on the input voltage this means heat. He uses a large heat sink and a small ventilator to get rid of the heat.

P1140607 P1140619



P1140647

A standalone streaming media device based on Raspberry Pi and HiFiBerry DAC

This is the most advanced HiFiBerry DAC setup we have seen so far. A German user integrated not only the Raspberry Pi and the DAC in a nice enclosure, but also a switching power supply. Power is connected using the onboard header on the HiFiBerry DAC and a USB WiFi Dongle is used for wireless connectivity.

IMG_2336IMG_2334 IMG_2333 IMG_2332

Cheat sheet: sample rates and clock frequencies

I2S audio connections usually use 3 different clocks: a frame clock, a bit clock and a master clock that must be synchronized. This is just a small sheet showing different sample rates for the standard sample rates. One thing that is important for anybody designing I2S audio interconnects: The frequencies can be relatively high. Make sure, you keep the traces as short and use countermeasures against ringing. Otherwise your circuit might interfere other devices.

Sample rate 32xfs 64xfs 128xfs 256xfs 512xfs
44.1kHz 1.4112MHz 2.8224MHz 5.6448MHz 11.2896MHz 22.5792MHz
48kHz 1.536MHz 3.072MHz 6.144MHz 12.288MHz 24.576MHz

As we start looking into Class-D audio, we want to see what’s going on above the audio band. ┬áNow, a new instrument arrived – a spectrum analyzer with integrated tracking generator. It is the Rigol DSA815. For its price, the build quality is very good. Unfortunately we have to get some test cables with N-plugs first. Therefore we can’t say much about it now.

dsa815

Stacking headers

Some HiFiBerry users asked how to connect other devices to the Raspberry Pi with HiFiBerry DAC installed. An easy solution are stacking headers. It took us some time to find a supplier for these headers, but finally we got a few. A HiFiBerry DAC with the stacking header instead of the normal 26-pin connector looks like this:

stackingheader

The headers are now available in our HiFiBerry shop.