This is about how to make my system better. I know it’s possibly an endless discussion, but I thought its still worth starting it… and I would be grateful for some good advise.
I must admit I’m an extreme computer audio newbie. It was Raspyfi/Volumio, which made me venture into computer audio, so I started cautious with Volumio+Raspy and the HifiMeDIY async DAC (ES Sabre 9023), which now feed into the line-in of my Yamaha AX396 Receiver (yes, I know this is old stuff). Because my phone charger didn’t had enough power, I am currently using a USB hub which I bought about 10 years ago and which has a separate power supply. The hub thus connects grid, hard drive, raspy power line in and raspy data USB. The DAC occupies the other USB slot of the raspy. Things work well, and I was happy, but then I made a direct comparison:
FLAC read by Volumio and feed through the DAC into my amp
vs.
The CD from which I obtained the FLAC, played by my 10 years old Yamaha CDX396.
Sorry, but the CD Player won by far.
So what should I do to improve the Volumio System? My aim was to finally abandon my CD collection, but up to now, this is not gonna happen as long as there is a clear and audible quality difference. Take this as the benchmark, what would you suggest as the most economic way to reach it?
Are you using this hifimediy.com/index.php?route=pr … uct_id=123 ?
USB DAC is not the best thing for RasPi, try i2s DAC like hifiBerry or DIYINHK ES9023, both are excellent i2s DAC.
Also consider separating the power rail for the DAC using a very good regulated dedicated power supply or battery. There are many discussion saying dedicated good power supply to the DAC can improve the sonic performance.
Thanks for the answer!
Yes, the link points to the DAC I have here. The non-async version was once praised as a bang for the buck solution by Michelangelo in the Raspyfi forum. That’s why I bought this one.
Sorry that I missed to specify further that my DIY-skills are pretty limited. I have no equipment or training in soldering. So can I connect the I2s DAC without bigger manipulations?
Moreover, I know that the power supply can be a problem, but up to now, I couldn’t find anything like a “clean” power supply that does not require extensive DIY or would be a completely financial overkill. I mean, spending 600€ for a USB power supply to feed a 36€ Raspberry pi is pretty ridiculous.
(For security reasons, I am definitely not going to solder anything which is on high voltage. I might try on 5V but for sure I am not going to experiment with 220V, so this sorts out all DIY power supplies).
i2s DAC with minimum fuss with Rpi is using Hifiberry, but you still have to solder the P5 pins on Rpi. Then you can invest a bit on good handphone charger (eg. iPad original charger) as the power supply to the Rpi which also power the Hifiberry DAC from the P5 directly. There are a lot of discussion in the forum with a lot of pictures covering this setup… and Hifiberry website also very helpful, even with instruction how to solder the P5 pin. Good luck…
If you are willing to do some soldering with low power 5v then you can buy a non switching 5v ac/dc transformer rated 2A and use it instead of the switching ones that are so common now.
Next step is to solder a 100uf cap and a 100nf cap in parallel as close as possible to the pi.
You can do so also for the 5v supply of the dac thus “isolating” the power supply.
If your dac is the one that feeds from the USB, this would require to go into the dac board.
Another option is to use something like diyinhk power supply board.
Again use dac or ac non switching transformer so you just have the low dc cable coming out
And no high ac to deal with. Hope this helps
There is no proof or measurement that shows that a cleaner power supply (as long as you use a reasonably clean one, like a normal switching one) improves the sound. This is because the DAC (and the op-amp inside) operates much faster than the oscillations of input power and because sound is orders of magnitude “slower” than the op-amp.
There was a link here somewhere to a website that did measurements of cleanliness of different power supplies. Then I asked him explicitly “but how much the sound is actually affected by this lower quality power supplies with more ripple?” and the guy, that had all the required instrumentation (not a difficult measurement) avoided answering me because hey, sound is the same no matter the PSU.
Of course you may “feel” a different sound, but since instrumentation shows no change, I would think twice before hacking into the DAC itself.
Noise can affect the digital signal, not just the opamp. Switching power supply may generate high frequency noise. And the cheap ones are not always clean.
Interference with hs digital data can be problematic.
But… Usually there are LDOs and capacitors on the dac supply that do quite a good job.
Though a linear power supply is considered better, there is no insurance that there is a significant change.
But then again it’s not difficult nor expensive to try this, if no dac hacking is required.
Thanks for all your contributions!
Indeed, I once had someone here with a battery pack that provides backup-power to recharge phones on USB 5V level. The Pi runs fine on the battery, but I couldn’t notice any sound difference. So if the psu makes any difference, the first step would be to separate the DAC from the Pi. But then again, I am wondering if the improvement is sufficiently large with the given hardware or if it’s still so marginal that I will have to invest in a different DAC anyway.
I think the configuration
| Volumio --> I2s to optical --> optical to analog |
sounds quite interesting in that respect. (See here: can-raspberrypi-truly-high-end-player-correct-hwsetup-t1226.html )
It would avoid the USB issues, automatically separate the power for the pi and the (final) DA conversion and allows to choose among more DAC’s (for the optical to analog) that are obviously on a hifi-level because the demand for optical to analog conversion is not restricted to computer enthusiasts but also involves old school hifi-guys that seek to upgrade their CD/DVD Player.
Good luck…