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Poll for Topping PA5 owners only please.

Is your Topping PA5 amp defective?

  • Yes

    Votes: 80 44.2%
  • No

    Votes: 101 55.8%

  • Total voters
    181

Eggs Ackley

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Poll for PA5 owners to report product defects. Discussion for any solutions. I think it would be useful to get a handle on some numbers to estimate just how wide spread the issues are.

Addendum:
Here is Topping's response to the PA5 issues...
 
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OP
Eggs Ackley

Eggs Ackley

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Had mine for 128 days with zero issues. Knock on wood.
 

IPunchCholla

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90+ days averaging a few hours of use per day. No issues.
 

REK2575

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Partly tongue-in-cheek, but maybe there should be a 3rd choice: "No, but I'm a bit worried" ;) That would be the one I select. The incidence of sudden unit failure being reported on the main PA5 Review thread has gotten my attention for sure -- and it seems to have gotten Topping's attention as well.

My PA5 is only a couple weeks old, and it has worked perfectly since I got it. It was an upgrade from my old PA3 (which worked perfectly for a year and a half of consistent use, no complaints). But the improvement from the PA3 to the PA5 is light and day. I can't go back to the PA3 having gotten used to the excellent sound of the PA5.

Anyway, I'm on the fence as to whether I should hold onto my PA5, keeping fingers crossed that it doesn't suddenly go belly up, or if I should return it in exchange for a PA3S, which also sounds like a step up from the original PA3. All things being equal, though, I'd like to hold onto my PA5!
 

Selkirks

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Mar 23, 2022
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I've used one 16 hours a day for 2 months. Hoping for the best but expecting the worst. If it dies I'll go back to my dual Hypex NC500 amp while they (hopefully) fix the issue.
 

mckirk

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Apr 22, 2022
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I got mine at the end of January and it started having the "cracking on left channel" issue about two weeks ago. I've already returned it sadly, so I can't look up its serial number anymore.

One thing I was wondering about: I had the amp plugged into an automatic power strip that kills the power when the main device powers off. I suspect the amp did not particularly like that, as it produced popping sounds whenever it lost its power without being turned off separately first.
I will admit I have no clue about how these amps are designed, and whether it's even possible that that has anything to do with the left-channel issue, but I thought I'd mention it in case it turns out to be a factor distinguishing the defective units from the surviving ones.
 

tonycollinet

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I've used one 16 hours a day for 2 months. Hoping for the best but expecting the worst. If it dies I'll go back to my dual Hypex NC500 amp while they (hopefully) fix the issue.
Just out of interest, why do you use the PA5 in preference to the Hypex NC500 based amp?
 

Selkirks

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Just out of interest, why do you use the PA5 in preference to the Hypex NC500 based amp?
The PA5 just subjectively sounds "right" to my ears/brain with the speakers I'm using. With that said, the Hypex amp has it beat in some areas and it's been problem free for over 5 years.
 
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GeekyBastard

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I got mine at the end of January and it started having the "cracking on left channel" issue about two weeks ago. I've already returned it sadly, so I can't look up its serial number anymore.
Interesting, your account seems really new (just registered several hours ago), and your only interaction on this forum was reporting your PA5 got problem... Hmmm...

This is what I meant above, some kind of proof would be nice.
 

cfo92130

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Feb 18, 2022
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I listen PA5 everyday since beginning of Feb without any issue so far ( SN 2112xxxxxx ).
The only negative point is its power consumption of 7w in idle mode.
 

Nzama

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Apr 14, 2022
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Interesting, your account seems really new (just registered several hours ago), and your only interaction on this forum was reporting your PA5 got problem... Hmmm...

This is what I meant above, some kind of proof would be nice.
I also voted and have a recent account with only pa5 interaction. For what is worth it I shared email with topping and a video of the defect.

Still your point is valid, the risk of manipulation is there!
 
D

Deleted member 46664

Guest
I got mine at the end of January and it started having the "cracking on left channel" issue about two weeks ago. I've already returned it sadly, so I can't look up its serial number anymore.

One thing I was wondering about: I had the amp plugged into an automatic power strip that kills the power when the main device powers off. I suspect the amp did not particularly like that, as it produced popping sounds whenever it lost its power without being turned off separately first.
I will admit I have no clue about how these amps are designed, and whether it's even possible that that has anything to do with the left-channel issue, but I thought I'd mention it in case it turns out to be a factor distinguishing the defective units from the surviving ones.

These little mini-amps with the external supplies (and even some with internal supplies) are not intended to be turned off and started back up repeatedly. The power supply should be plugged into a live outlet and left on all the time. The amp itself is also always on, but when "off" from it's power switch it is in a deep standby mode.

The reason for this is the large reservoir "Bulk" capacitors used on the amplifier boards and, often, in the power supply as well. When you first connect the Power cord to the supply there is a rather large inrush of current until it gets charged up and working. When you first connect the amp to the power supply there is another large inrush of current while the amp's big caps charge up and settle down. When you power cycle with both devices connected that inrush can be big enough to do damage.

Neither device is likely to be designed to handle this repeatedly. Each repetition puts a very large strain on the rectifier diodes and AC filters in the power supply. Each time causes some trivial amount of damage, until one day it starts acting up and eventually dies.

This issue came to the fore with people shutting down their PCs and then turning off the "babysitter switch" on the back of the case. We had a large rash of failed power supplies because the current inrush was popping the rectifiers inside. We ended up replacing quite a few under warranty and advising that the power switch be left on all the time. After that, very few supply failures.

So .... best advice... to avoid the "inrush" problem, hook up your mini-amp, plug it into a live outlet... and leave it "on" all the time. When not in use, use the "on-off" switch on the amplifier to put it into standby mode.
 
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tonycollinet

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These little mini-amps with the external supplies (and even some with internal supplies) are not intended to be turned off and started back up repeatedly. The power supply should be plugged into a live outlet and left on all the time. The amp itself is also always on, but when "off" from it's power switch it is in a deep standby mode.

The reason for this is the large reservoir "Bulk" capacitors used on the amplifier boards and, often, in the power supply as well. When you first connect the Power cord to the supply there is a rather large inrush of current until it gets charged up and working. When you first connect the amp to the power supply there is another large inrush of current while the amp's big caps charge up and settle down. When you power cycle with both devices connected that inrush can be big enough to do damage.

Neither device is likely to be designed to handle this repeatedly. Each repetition puts a very large strain on the rectifier diodes and AC filters in the power supply. Each time causes some trivial amount of damage, until one day it starts acting up and eventually dies.

This issue came to the fore with people shutting down their PCs and then turning off the "babysitter switch" on the back of the case. We had a large rash of failed power supplies because the current inrush was popping the rectifiers inside. We ended up replacing quite a few under warranty and advising that the power switch be left on all the time. After that, very few supply failures.

So .... best advice... to avoid the "inrush" problem, hook up your mini-amp, plug it into a live outlet... and leave it "on" all the time. When not in use, use the "on-off" switch on the amplifier to put it into standby mode.
Any mains powered device which cannot cope with being switched on/off from the mains is a faulty design IMO.

In my previous life we designed inverter based motor controls. These went up to megawatts, but in my arena only up to 90kW. They had huge capacitor banks to create a DC link from which high power 3 phase variable frequency power to motors could be derived. The majority would be connected to 3 phase 400V supplies.

They were not intended to be "controlled" by mains power being cycled, but sometimes they were. We eventually incorporated the "on off cycle" test into our test program.

The test unit had to survive (depending on size) 100,000 on/off cycles - smaller power ratings up to about 15kW at two cycles per minute. The cycle rate was selected to maximise the power dissipation in the inrush circuit.

Perhaps overkill for small domestic amps, but if an amp cannot survive at least a couple of cycles/day, then it is not fit for purpose.
 
D

Deleted member 46664

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Any mains powered device which cannot cope with being switched on/off from the mains is a faulty design IMO.

Perhaps overkill for small domestic amps, but if an amp cannot survive at least a couple of cycles/day, then it is not fit for purpose.

It turns out that we agree. Any consumer device that can't bear shutdown-restart cycles is under built and prone to failure.

That said ... we have to deal with the reality of how these things are actually built and they just aren't up to a couple of hundred power off/on cycles before they go defective.

Please note: I directed my comments to the one person talking about power cycling those brick supplies (that's what fails most often). I did not say and do not know that is the cause of the noise some people are experiencing. I was mostly concerned that this amp, and other similarly powered devices don't end up in the trash a few years early.
 

tonycollinet

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That said ... we have to deal with the reality of how these things are actually built and they just aren't up to a couple of hundred power off/on cycles before they go defective.
I'm not convinced that is the case. Do you have any data for it? And what do you mean by "these things"? Cheap amps? (the PA5 isn't) Class D? Small? (how small?) ...?
 
D

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I'm not convinced that is the case. Do you have any data for it?
Open up any brick type supply ... you're going to find 1 or 2 amp diodes in the input rectifier.
You're asking them to handle an inrush current that can reach 6 or 8 amp peaks.
They're only going to do that a limited number of times before they go pop.
 

Martinvb

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Just wondering: there has been some discussion on this forum about the downside of using single-ended input on the PA5. Is there any chance that using a mono-6,5mm to RCA adapter to connect a single-ended device could cause this noise? For now, I have disconnected my (single-ended) phono pre-amp from the PA5, until this issue has been thoroughly investigated.
 
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