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Strange polarity issue with new amplifier (Topping PA5 II Plus)

MAB

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Yes, but I wouldn't read too much into it. He had gaps between periods of relatively frequent posting before that too, and kept posting through the L30 issues.
Yeah, his on and off participation at ASR may or may not be related to the poor quality and reliability and after-sales support of Topping's products.
 

mhardy6647

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No great loss.

Topping just lurches awkwardly from one fiasco to another- like a drunk person staggers down a dark alley late at night, crashing into dumpsters, parked cars and trash, before tripping and falling face first into an open drain and passing out. Funny to watch if it wasn't so pathetic.
I'd offer a slightly more positive (or, perhaps, more optimistic) spin: Topping's more like a nearly infinite ;) cadre of monkeys, each with a typewriter word processor laptop tablet workstation. Signal to noise ratio of the output maybe poor, but an occasional sonnet pops out. You know? ;)

Actually, that metaphor probably works better for Schiit - and not just because of that tight monkey/Schiit correlation (so to speak). :cool:
For every <insert the dumb, bad pun name of a really, truly good Schiit product of your choice>, there's a SOL, and a SYN, and a Rekkr, and a Loki...
The stupid silly Schiit products might not be actively bad, but they're generally actively silly for one (or more) substantive reasons.
 

Holdt

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No great loss.

Topping just lurches awkwardly from one fiasco to another- like a drunk person staggers down a dark alley late at night, crashing into dumpsters, parked cars and trash, before tripping and falling face first into an open drain and passing out. Funny to watch if it wasn't so pathetic.
LOL, so very blunt. -Refreshing.
 

Holdt

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I'd offer a slightly more positive (or, perhaps, more optimistic) spin: Topping's more like a nearly infinite ;) cadre of monkeys, each with a typewriter word processor laptop tablet workstation. Signal to noise ratio of the output maybe poor, but an occasional sonnet pops out. You know? ;)

Actually, that metaphor probably works better for Schiit - and not just because of that tight monkey/Schiit correlation (so to speak). :cool:
For every <insert the dumb, bad pun name of a really, truly good Schiit product of your choice>, there's a SOL, and a SYN, and a Rekkr, and a Loki...
The stupid silly Schiit products might not be actively bad, but they're generally actively silly for one (or more) substantive reasons.
Sort of like Murphys Law^-1?
 

Blumlein 88

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No great loss.

Topping just lurches awkwardly from one fiasco to another- like a drunk person staggers down a dark alley late at night, crashing into dumpsters, parked cars and trash, before tripping and falling face first into an open drain and passing out. Funny to watch if it wasn't so pathetic.
I guess I'm a Topping fanboy. As a disclosure I have one of their DACs. Off the charts performance/price ratio. I don't think this description fits with reality.

By reputation, and from what I've seen reality, they may have some QC issues. Also they might cut it close on some aspects of design. And I might expect it given pricing. OTOH, they are near the very tip top in basic performance of some of their products at a very low price point. I do think it makes sense to give a little more leeway at low enough pricing. I also think it isn't like 1 in 10 of their products is a problem. Even that level of unreliability would kill the company I'd think. If these are unacceptable compromises one can say that without a lurid description like the above.

I've also repaired some highly expensive gear of the highest repute over the years. Dumb things like polar capacitors installed incorrectly. Even the channel inversion the topic of this thread. Correction of inherent design flaws guaranteed to lead to a short life. An amp with wiring too close to ground so that the voltage spikes at turn on/off caused a loud SNAP sound from arcing over to ground. And others that may not to come to mind at the moment.

Not everything needs to be built like a brick outhouse as they say. I also don't think Topping is guilty of doing the following where you pay for one thing and find something else inside. That is entirely too common.

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ban25

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I guess I'm a Topping fanboy. As a disclosure I have one of their DACs. Off the charts performance/price ratio. I don't think this description fits with reality.

By reputation, and from what I've seen reality, they may have some QC issues. Also they might cut it close on some aspects of design. And I might expect it given pricing. OTOH, they are near the very tip top in basic performance of some of their products at a very low price point. I do think it makes sense to give a little more leeway at low enough pricing. I also think it isn't like 1 in 10 of their products is a problem. Even that level of unreliability would kill the company I'd think. If these are unacceptable compromises one can say that without a lurid description like the above.

I've also repaired some highly expensive gear of the highest repute over the years. Dumb things like polar capacitors installed incorrectly. Even the channel inversion the topic of this thread. Correction of inherent design flaws guaranteed to lead to a short life. An amp with wiring too close to ground so that the voltage spikes at turn on/off caused a loud SNAP sound from arcing over to ground. And others that may not to come to mind at the moment.

Not everything needs to be built like a brick outhouse as they say. I also don't think Topping is guilty of doing the following where you pay for one thing and find something else inside. That is entirely too common.
1 in 10? More like 1 in 2:

 

MAB

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I also think it isn't like 1 in 10 of their products is a problem.
It's just that at least one of their products has near 100% fail rate, and was never addressed, and the after-sales service ran a crooked operation, and then after-sales show up and say they want to help in the broken PA5 thread but then immediately disappeared, and the only service available is by and ASR member, and they just steamroll-release another slightly different version, but with the same encapsulation and it is breaking too, and then their technical rep ghosts the "ask me questions thread" as soon as the questions get slightly difficult.
At some point, most people prioritize quality and reliability over everything else in a quality story. Often times, companies can take simple actions to address systematic quality issues.
Also, for me it's two out of three. I got a PA5 with the same problem as everyone else. I had an A30 Pro fail, riddled with cold solder joints. I need to dig up the photo, the solder is cold and the board is corroded where it wasn't cleaned, the thermal grease is missing under the heatsink for half the output devices. It was powerful, until it wasn't though... My Topping DAC still works last I checked, although I decided some time ago that for my use condition a DAC without DSP is like a car without steering wheel.

So yeah, it's more like some of their products are basically 100% broken, and their after-sales service is also 100% broken. And the rest of the products that do work aren't worth the risk. If I close my eyes, a Topping DAC is just like any other.
 

restorer-john

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It's just that at least one of their products has near 100% fail rate, and was never addressed, and the after-sales service ran a crooked operation, and then after-sales show up and say they want to help in the broken PA5 thread but then immediately disappeared, and the only service available is by and ASR member, and they just steamroll-release another slightly different version, but with the same encapsulation and it is breaking too, and then their technical rep ghosts the "ask me questions thread" as soon as the questions get slightly difficult.

So true.
 

Holdt

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It's just that at least one of their products has near 100% fail rate, and was never addressed, and the after-sales service ran a crooked operation, and then after-sales show up and say they want to help in the broken PA5 thread but then immediately disappeared, and the only service available is by and ASR member,

Wow! -The work from this guy is extraordinary! :oops:
 

GXAlan

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Man. I did this super complex PA-5 versus Marantz test with null testing and all sorts of analysis, then it turned out that the channels were swapped and I had egg on my face, but now I wonder if it was incorrectly wired internally!
 

Blumlein 88

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Well I never read any threads on the PA5. I didn't know it had been such a problem.
 

restorer-john

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Man. I did this super complex PA-5 versus Marantz test with null testing and all sorts of analysis, then it turned out that the channels were swapped and I had egg on my face, but now I wonder if it was incorrectly wired internally!

Do you still have the PA-5? Have a look inside.
 

MAB

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Well I never read any threads on the PA5. I didn't know it had been such a problem.
Yeah, my experience was pretty surreal. My left channel blew the first week, sound of rustling leaves plus a big DC offset, just like many of the other fails. The return service was surreal, and ended up with my unit apparently getting lost. I actually applied constant pressure for months and ended up Shenzhen audio giving me a refund (except for the shipping)! I blather on about it like the world cares throughout this thread;):
It was so bad that people who bought two amps had both break. People got replacements that then went on to fail.:facepalm: The fact that multiple people got multiple fails, combined with the fact that units that were both repaired and replaced went on to fail is an incredibly damning statistic that usually indicates a systematic fail mode.
John writing stuff like this in the E30 thread while he and the whole reseller crowd were ghosting the actual PA5 issue and people pleading with the resellers for their money back or something:
We tried some improvement on the PA5 regarding the issue and we had 20 of those new units running for over a month now without any issue. But apparently we all know that the pop noise issue comes up randomly and only after a few months. It's a very touchy issue that we still cannot 100% pin point what the issue is. And also published else where we are extending the warranty for all of our amplifier line. If this doesn't show our care for our customers, I don't know what does. Does it really matter that much if I constantly replying to comments here? It's always recommended to get the unit from the nearest authorised distributor/seller so in case something happens one can get the best service. And I believe this is the best case scenario.
Super insulting, since nobody was getting relief. And totally uninspiring from a debug standpoint.

A few months later, my allegedly lost PA5 comes back to me in an unpadded soft-mailer, with the same wire tie on the power supply that I shipped it with, in the exact same broken state. Shortly after that, Gamerpaddy posts a request for a PA5 to debug. So put my broken amp in a nice box and mail it to Germany for him to dig into. I mean, at this point, why not?
And of Gamerpaddy delivers the module replacement for everybody, find details here:
Which is a good thing when half of everybody seems like they going to need a fix or two.
 

GXAlan

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Do you still have the PA-5? Have a look inside.

Nope. It actually was someone else's and it was returned within the trial period due to the reliability issue.

Edit: Reliability is a reason why I see something like the Meyer Amie and think, while this seems really expensive, it has integrated emi/rfi filtering, an integrated surge suppression that handles high-voltage transients up to several kilovolts *and* is UL Listed? Sign me up. It also handled being dropped 4-5 ft with just has cosmetic damage as verified by Amir's measurements at 106 dB.
 

ban25

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Maybe I'm just lucky, but enjoying my ~2 year old PA5 original used almost daily.
Due to improper encapsulation, heat death will catch up to it eventually. You will probably lose one channel first.
 
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