Topping PA5 Review (Amplifier)

[Eggs Ackley]

I would also swap the speaker connects left to right and see if the noise moves to the other speaker.

 

[Rafaille]

At least 4 people (me included) have reported this issue with the PA5, with identical symptoms. Although your suggestions are fair, and I have already tested them all, I am sure others have done so as well. Some PA5 amps clearly are faulty, it maybe something rather trivial that quality control has missed but I am not qualified enough to attempt a repair, if at all possible.
It is a shame as I really enjoy this amp, but I suppose at this price point, quality control is where money can be spared...
I will try again and ask for a replacement, hoping I won't get another faulty unit.

 

[wlgreg]

Perhaps the issue is with your system. Have you done any trouble shooting beyond the amp?

For the first unit, i completely disconnected DAC and Pi streamer; Only equipmet connected was PA5 and speakers (Kef Q300). New quality cables (from worlds best cables). Static was consistently present. Switching to my “backup” rig (Pi 4 + hifiberry DAC HAT + Amp HAT) eliminated the issue, so i'm confident it's not a problem with the speakers.

i will repeat these tests with the replacement unit, although honestly i'm not expecting a different result.

 

[AudioArchitech]

I suggest adding a little more work to identify the cause.
Turn off the power of the PA5 and disconnect all the cables connected to the input terminal of the PA5.
The PA5 and speakers remain connected.
The only cables connected to the PA5 are the AC adapter cable and speaker cable.
In that state, turn on the power of PA5.
If you still hear a lot of noise from the speakers, it's probably a PA5 failure.

Or, even if the PA5 is normal, the noise may be unacceptable.
If your speakers are very efficient.
In that case, it is difficult to use PA5 in your environment.

How long have you had yours?

 

[BadAudioAdvice]

I have had the exact same popping/crackling issue on my PA5 for about a week.
Left channel only as well.
I think I read that someone else had this issue a few pages back in this thread.
Just wondering, to those who have this issue: Did you buy it very early on, only a few days after release? Do you also have a loose speaker binding post? Could be a batch problem...
I will enquire with Shenzhenaudio about a return? Anyone has some experience with them?

I had started experiencing this intermittent static noise out of the right channel when nothing was playing, and then a thump noise when I switched off the amplifier.

This started a couple of weeks ago, and I had PM'd JohnYang before posting to this thread, however I did not get a response. I didn't want to start posting in the thread here until I knew that it was an issue with the amp. I hadn't checked the thread in a week, and now I see that by no means am I am the only one who is having these problems.

I ordered it through APOS almost as soon as they were available, right after Amir's review.

I does run quite warm, but I have lots of space around it. I have the E50 DAC and ifi Zen Phono connected to it.

I've never had the volume knob higher than 55% - most listening is at 35-40% position. Used it with Technics SB-C700, Omega Super3XRS, and Magnepan MMGs.

Most days I turn it off after listening to music, but there have been a number of days when I've left it on overnight. I've had it connected to different outlets in different rooms, but the intermittent noise in the right channel problem still persisted.

It was a bit nerve racking, because I was selling my Omega speakers, and the person was coming over to listen to them before buying them, and of course the PA5 was acting up that day when I first powered it on...fortunately a few hours later the problem went away, and the speaker audition went fine. Either way, not acceptable for something so new.

 

[AudioArchitech]

It’s disappointing, still hoping this gets dealt with better. HiFiGo is still insisting that I ship it to them in China so they can ship it to Topping for testing and repair. I feel like I’m going to be out of amplifier for over 2 months only to likely have the same issue come back. My confidence in Topping is severely diminished at this point.

 

[armaster]

Hi,

I noticed some relay clicks inside PA5. If I select input channel 2, then I can hear relay when switch power on and off, but if I select input channel 1, there is no relay sound when switching power on or off.

Does anyone noticed the same behaviour?
What is the purpose of this relay and why only for channel 2?

Thanks.

 

[somebodyelse]

Probably the relay that does the input switching - channel 1 on the normally closed contact and channel 2 on the normally open one. With channel 1 selected the relay doesn't switch when the power state changes, but with channel 2 selected it does.

 

[armaster]

I don't t understand. If I change channel switch, there is no relay click. I can hear relay click (delayed) only when change power switch and input switch is set to channel 2.

Can anyone PA5 owner confirm this relay behavior?

 

[Loathecliff]

I had PM'd JohnYang before posting to this thread, however I did not get a response.

Thxs BAA. Worth noting.

 

[JSmith]

I had PM'd JohnYang before posting to this thread, however I did not get a response

Was it after the 25th of March?

JSmith

 

[Drengur]

My guess is a dual mono Benchmark competitor in terms of numbers.

 

[BadAudioAdvice]

Was it after the 25th of March?

March 26th.

 

[Billy Budapest]

View attachment 199152
My guess is a dual mono Benchmark competitor in terms of numbers.

Link? To the teaser photo, I mean.

 

[JSmith]

Link? To the teaser photo, I mean.

It's being discussed in this thread;

The World's First Power Amplifier with SINAD over 120!!!

@WolfX-700 so is this a April Fools prank or something real that is coming, or a mix of the two? There seems to be some confusion based on the Feb announcement on your site and the one from today that says it's a joke. :) JSmith

audiosciencereview.com

JSmith

 

[Loathecliff]

View attachment 199152
My guess is a dual mono Benchmark competitor in terms of numbers.

View attachment 199152
My guess is a dual mono Benchmark competitor in terms of numbers.

Hopefully any review sample will be randomly plucked from a busy production line.
(In retrospect I'm relieved I'm still at the Breeze 3116 point)

 

[EB1000]

The 1.2MHz spike indicates an internal bridging (or full-bridge topology with a common mode LPF). This isn't the best practice. If they used only differential LPF, where the two legs are operated at 180 deg out of phase, you wouldn't see the 600kHz component, just the effective 1.2MHz..

 

[Bleib]

Open it up! There is new technology inside hat measures way better than TPA3255.

Marketing mumbojumbo from Shenzenaudio

"PA5 has The newly developed Class D amplification circuit which uses multiple novel optimization techniques to fully push the performance and output power to the maximum. The new circuit provides crisp, clean and deep sound with completely inaudible noise floor. The fully balanced structure makes PA5 no more hum, no more noise, no more ground loop."

Or they are pushing it too hard which leads to some people having faulty units.

 

[pkane]

Or they are pushing it too hard which leads to some people having faulty units.

What I find interesting is some people are reporting that the unit runs quite hot. Mine has not become more than just slightly warm, even when testing it at 40-50W continuously for a few minutes.

 

[dsnyder0cnn]

What I find interesting is some people are reporting that the unit runs quite hot. Mine has not become more than just slightly warm, even when testing it at 40-50W continuously for a few minutes.

Mine has never become more than slightly warm either. It gets a little warmer than the L50 headphone amp, but never hot. I don't know how much power I'm asking it to deliver, but I'm running with the volume at maximum and around 12 dB of attenuation before the signal reaches the E50 DAC (in DAC mode, so full-out). We'll see how long it lasts, but so far, so good.