Hacker News Reader

Comment by mahyarm | Hacker News Reader

Is the audio any good? Would it compete on the level of an airport express?

Actually (unrelated to Pi 3), audio was recently improved in an experimental driver.

From the engineer who worked on it:

> I reimplemented the original PWM-based 11-bit audio @48kHz as 7-bit 2nd-order Sigma-Delta modulated at 781.25kHz. The effective noise floor with this scheme approximates that of CD-quality audio DACs.

from the forums https://www.raspberrypi.org/forums/viewtopic.php?f=29&t=1364...

That is a superlative discovery, and extremely intriguing. Thank you for sharing it!

No, the audio by default is pretty crap. There are several add-on daughterboards/hats available that use the i2s port to give better audio.

Yup, RPI's internal audio sounds rather dull, which you might not notice until you buy an external DAC :D.

The RPI can do great audio out of the box without USB, just don't use the 3.5mm jack. Instead, remember that HDMI does uncompressed bitstream audio!

You can connect the RPI to a dac/amp with HDMI input or a digital audio extractor. The best quality will be found by connecting to an HDMI to SPDIF extractor and then running that into a good quality DAC.

The nice thing about this solution is that you're not dependent on the horrible and CPU-sucking USB offered by the RPI.

That is a nice hack! I'm going to have to plug the HDMI port into my stereo amp and try this out.

How to connect a single hdmi cable to a monitor AND an amp?

HDMI amplifiers, DACs, and audio extractors (which give a clean digital bitstream on SPDIF) provide an HDMI output. The output HDMI will continue to carry the video portion of the signal and usually (if not always) the audio stream as well.

If it's the same as the previous models: no, the audio of the Raspberry Pi is pretty rudimentary (it uses PWM) [1]. However, you can use an external DAC to improve this.

[1] http://www.crazy-audio.com/2014/07/sound-quality-of-the-rasp...

A couple of years ago I bought a Raspberry Pi 2 to use as a music server. However, when playing through a Benchmark USB DAC I hear pops and clicks in the audio. Instead I bought a Cubox and use its Toslink output which works perfectly. Does anyone know if the USB audio issue have been fixed in the third version of the Raspberry Pi?

I had no problems with the first Raspberry Pi and a fiio e10k USB DAC.

Did the same and had clicks with a different USB DAC. I'm waiting to hear whether this one works too!

Connecting the analog audio of the RPi (1B) to my receiver causes the receiver's CPU to slow down to the point where it is unusable! It looks like the RPi puts out a DC-biased signal, and the receiver is seriously lacking input robustness. The two devices were also connected via HDMI, ruling out ground issues.

I've since moved the music setup to also use HDMI (the DAC in the receiver is bound to be better anyway), but sheesh, be warned.

How on earth do you know what your receiver's CPU is doing?

The UI slows down gradually until the whole thing is unresponsive, reproducibly. IIRC disconnect the analog input, and the UI picks right back up.

I've no idea if it's a priority interrupt firing too much, body diode current weirdness, or some thermal issue. And I'm certainly not going to keep teasing the fault to figure it out.

Yeah, wow. That's wacky.

Reply on news.ycombinator.com