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PA5 & E50 & rapsberry - how to get it work :-)

kchap

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Do you have any data to back up this statement?

Not on the E50 he hasn't. I can here very clear differences in distortion when using different USB power supplies with the E50.
I recently got my E50/L50 combo out of the cupboard and setup a third Raspberry Pi system. I do not hear any difference between all three DACs.

With the E50 I have used a "common or garden" 5V USB plug pack, a 5V USB outlet on a PowerTech brand PDU strip and currently, a Comsol 3 port USB charger. The Comsol unit feeds both the Raspberry Pi and the E50. I have never detected any audible differences with the three power sources.

That is all subjective, but I have not got an ADC so cannot perform proper tests. Until someone publishes evidence to the contrary I'm happy to go with current thinking that any 5V supply that meets the USB standard should be ok.
 

Blew

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I recently got my E50/L50 combo out of the cupboard and setup a third Raspberry Pi system. I do not hear any difference between all three DACs.
That could many reasons why that may be the case. Off the top of my head it could potentially be due to:
  • Similar distortion in your other DACs
  • Your system doesn't reveal enough detail to hear the distortion
  • Your electricity supply is less noisy than mine and many others
  • The distortion is different for 50Hz/240v and 60Hz/120v electricity (I'm 50Hz/240v)
  • All your USB adapters just happen to be much cleaner than all of mine and many others
  • There is some ground loop in my systems that I can't resolve. However, my desk system is fully balanced now, which unfortunately doesn't appear to improve anything that I can hear over single ended apart from extra volume on the headphones, so I doubt that's the cause.
  • You don't know what to listen for or are used to the sound of the distortion
  • Your hearing is not good enough to hear the distortion
With the E50 I have used a "common or garden" 5V USB plug pack, a 5V USB outlet on a PowerTech brand PDU strip and currently, a Comsol 3 port USB charger. The Comsol unit feeds both the Raspberry Pi and the E50. I have never detected any audible differences with the three power sources.

That is all subjective, but I have not got an ADC so cannot perform proper tests. Until someone publishes evidence to the contrary I'm happy to go with current thinking that any 5V supply that meets the USB standard should be ok.
There's plenty of testing that's been done on noise levels of 5V USB power. There's also much much more anecdotal reporting of the audible differences that electricity supply noise has on DACs in general, and on the E50 specifically. I don't think it's reasonable to ignore all of that just because nobody has performed thorough testing on electricity supply noise on the Topping E50 yet.

I can personally attest to that. I was not very impressed with the sound coming from the E50 when I ran it off the 1A USB port on two of my amps, then found a noticeable improvement when using a random USB charger that I had lying around, then noticed a further improvement when using an Apple iPad charger. Higher frequencies are less "harsh" and "grating", and sound more precise. It's not 100% resolved yet and so I'm looking at what I can do to improve it further. I've ordered a USB battery charger after hearing reports of that helping a lot, so will see how that goes.

My desk setup is Pi4 -> USB -> E50 (DAC mode, balanced) -> TRS to XLR balanced cables -> Singxer SA-1 (XLR input) -> 4.4m balanced headphone cable -> HD660S
 

kchap

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That could many reasons why that may be the case. Off the top of my head it could potentially be due to:
  • Similar distortion in your other DACs
  • Your system doesn't reveal enough detail to hear the distortion
  • Your electricity supply is less noisy than mine and many others
  • The distortion is different for 50Hz/240v and 60Hz/120v electricity (I'm 50Hz/240v)
  • All your USB adapters just happen to be much cleaner than all of mine and many others
  • There is some ground loop in my systems that I can't resolve. However, my desk system is fully balanced now, which unfortunately doesn't appear to improve anything that I can hear over single ended apart from extra volume on the headphones, so I doubt that's the cause.
  • You don't know what to listen for or are used to the sound of the distortion
  • Your hearing is not good enough to hear the distortion

There's plenty of testing that's been done on noise levels of 5V USB power. There's also much much more anecdotal reporting of the audible differences that electricity supply noise has on DACs in general, and on the E50 specifically. I don't think it's reasonable to ignore all of that just because nobody has performed thorough testing on electricity supply noise on the Topping E50 yet.

I can personally attest to that. I was not very impressed with the sound coming from the E50 when I ran it off the 1A USB port on two of my amps, then found a noticeable improvement when using a random USB charger that I had lying around, then noticed a further improvement when using an Apple iPad charger. Higher frequencies are less "harsh" and "grating", and sound more precise. It's not 100% resolved yet and so I'm looking at what I can do to improve it further. I've ordered a USB battery charger after hearing reports of that helping a lot, so will see how that goes.

My desk setup is Pi4 -> USB -> E50 (DAC mode, balanced) -> TRS to XLR balanced cables -> Singxer SA-1 (XLR input) -> 4.4m balanced headphone cable -> HD660S
Just lost my reply. So I will cut to the chase.

If you had said you had problems with a particular USB PSU then fair enough. They are a commodity item. Most will be fit for purpose but some will suffer from poor design, aging components or just be out and out faulty. Any noise and ripple in that majority of PSUs that are in spec is easily dealt with by the DACs onboard regulator(s).
 

Blew

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bopes

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For my secondary (office/mancave) setup, I'm running a RPi4B (Ropieee) powered via a PoE HAT into a Topping E50/L50/PA5. Speakers are Emotiva B1+ and SE8 sub.

The sound is great - clean, clear, no audible distortion and more than capable of causing hearing damage.

Embarrassingly close to my £11k main rig.......

Which device do you use to control the speaker volume with this setup? How is it wired? I'm confused because the E50 only has one set of TRS outputs.
 

bopes

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Still trying to understand how to use the L50 with E50 and PA5. Already have the latter two, but waiting to order the L50 for now. Can someone please explain how to run the wires and control the speaker volume?
 

gfinlays

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E50 TRS output to L50 TRS input, L50 pass-through to PA5 TRS input. You can control the speaker volume via the remote of the E50 in preamp mode, or keep the E50 in DAC mode and control via the volume knob on the PA5. Simples.....
 

Blew

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Just lost my reply. So I will cut to the chase.

If you had said you had problems with a particular USB PSU then fair enough. They are a commodity item. Most will be fit for purpose but some will suffer from poor design, aging components or just be out and out faulty. Any noise and ripple in that majority of PSUs that are in spec is easily dealt with by the DACs onboard regulator(s).
Since my last comment I have obtained a USB battery bank to use with the E50. When I run the E50 off the battery bank I notice a distinct improvement over using any USB charger to power the E50. I've also noticed that music played via my laptop USB is much much better when the E50 is powered by the battery bank compared to when powered by a USB charger. Previously I was only using the Rpi because music played via on my laptop via USB to the E50 sounded terrible.

So I can only think that this is either due to the USB power supply noise being much cleaner on a battery bank, or that all of this is because of some ground loop issue that's resolved when the E50 is powered separately. Given that the audio quality from my laptop to the E50 via USB is much better when using the battery bank, I'm guessing that suggests the latter? However, as mentioned above, I'm using fully balanced connections between E50, headphones amp, and headphones. So I'm very confused.
 

FuzzTone

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I have a cheapo LPS on mine into the stock PA 5 setup and it sounds wonderful. I've been loving it with an M50.
 
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