Poll for Topping PA5 owners only please.

[Deleted member 46664]

Btw, i generally very much appreciate your point Blake. You seems to be very knowledgeable.
Sometimes I have the feeling you use autoritas arguments that shall have no place in (?) in ASR.

Since when is it wrong to encourage people to deal with the reality before them?

 

[Loathecliff]

Since when is it wrong to encourage people to deal with the reality before them?

Ask the widow of a messenger. They tend to be ambivalent.

 

[antcollinet]

It is a possiblity. We don't actually know what's causing it yet.


The thing is that we do know that repeatedly power cycling these little brick supplies will eventually kill them. You just need to take one apart and see the rectifier diodes to know that it's not going to live forever if you're turning the AC on and off all the time. We aren't talking about instant death ... it generally reduces the brick's lifetime from 5 or 6 years to something like a year.

This is not specific to the PA5 .... this is a well known issue with ALL power bricks.

Again - you have the data for this do you? This is not a forum for zero evidence opinions.

What about laptop power bricks? They are plugged and unplugged all the time. I've never had one fail in around 20 years of laptop use, carrying from meeting to meeting, country to country, plugging and unplugging multiple times per day. I don't know anyone who has, in a former life of around 150 users of laptops. And they are basically the same thing. My own laptop is currently aroud nine years old, and I pay no attention to keeping it plugged in continuously. Power brick has lasted somewhat longer than a year.

You literally seem to be making it up as you go along.

 

[Deleted member 46664]

Again - you have the data for this do you? This is not a forum for zero evidence opinions.

What about laptop power bricks? They are plugged and unplugged all the time. I've never had one fail in around 20 years of laptop use, carrying from meeting to meeting, country to country, plugging and unplugging multiple times per day. I don't know anyone who has, in a former life of around 150 users of laptops. And they are basically the same thing. My own laptop is currently aroud nine years old, and I pay no attention to keeping it plugged in continuously. Power brick has lasted somewhat longer than a year.

You literally seem to be making it up as you go along.

Laptops are different than amplifiers. In a laptop the brick is basically a battery charger with almost no inrush current. This is not the same for an amplifier or other electronic device with large reservoir capacitors. It's not AC-on AC-off that's the problem, it is that large inrush of current needed to charge reservoir capacitors that causes the issue.

AND ... I'm not the only person here talking about this ... scroll back to post #50.

I get that you don't get it ... the problem appears to be that you don't get that you don't get it.

 

[E-Lint]

If a first posting new guy could jump in here for a bit of advice...I'm just getting back involved in the hobby after many years. The many reviews of the PA-5 and other things Topping had led me to wish to use it as the cornerstone of an all Topping stack. Now you guys have me nervous and I'm wondering if I should either pause or go another way entirely.

Just to show you how far behind the power curve I've been for awhile I am coming from a 12 year old NR-626 Onkyo AVR. I'm looking at *mid-fi* separates system that is somewhat future proof. After getting bleary-eyed trying to assess the different (myriad) DACs I am currently settled on the E50/L50 combo with the aforementioned PA-5. The M50 streamer appeals to me also even though the strange connections put me off a bit and needs more thought.

Existing speakers are ELAC UB52 (perhaps to be upgraded later - too new now) and I am getting set to rebuild a 23 year old set of Infinity Overture 3s for another room (interestingly I think Andrew Jones may have hand in them as well).

So the question I would put to you: is the PA-5 still a reliability question mark? I'm already tempting fate by getting multiple boxes at once so I see that risk. Final question: will the PA-5 have any problem for the UB52s? Or worse, would such a pairing contribute to an early demise for the PA-5?

Apologies if I have come in at the wrong place and time. I thank you for your kind help.

 

[IPunchCholla]

Laptops are different than amplifiers. In a laptop the brick is basically a battery charger with almost no inrush current. This is not the same for an amplifier or other electronic device with large reservoir capacitors. It's not AC-on AC-off that's the problem, it is that large inrush of current needed to charge reservoir capacitors that causes the issue.

AND ... I'm not the only person here talking about this ... scroll back to post #50.

I get that you don't get it ... the problem appears to be that you don't get that you don't get it.

I have no idea if you are right or wrong on this. This is because you’ve cited zero evidence, except a post that also cites no evidence. You hypothesis sounds reasonable to me, and you seem like you know what you are talking about, but if you want to convince others here, you will likely need to cite something that goes beyond anecdote.

 

[IPunchCholla]

If a first posting new guy could jump in here for a bit of advice...I'm just getting back involved in the hobby after many years. The many reviews of the PA-5 and other things Topping had led me to wish to use it as the cornerstone of an all Topping stack. Now you guys have me nervous and I'm wondering if I should either pause or go another way entirely.

Just to show you how far behind the power curve I've been for awhile I am coming from a 12 year old NR-626 Onkyo AVR. I'm looking at *mid-fi* separates system that is somewhat future proof. After getting bleary-eyed trying to assess the different (myriad) DACs I am currently settled on the E50/L50 combo with the aforementioned PA-5. The M50 streamer appeals to me also even though the strange connections put me off a bit and needs more thought.

Existing speakers are ELAC UB52 (perhaps to be upgraded later - too new now) and I am getting set to rebuild a 23 year old set of Infinity Overture 3s for another room (interestingly I think Andrew Jones may have hand in them as well).

So the question I would put to you: is the PA-5 still a reliability question mark? I'm already tempting fate by getting multiple boxes at once so I see that risk. Final question: will the PA-5 have any problem for the UB52s? Or worse, would such a pairing contribute to an early demise for the PA-5?

Apologies if I have come in at the wrong place and time. I thank you for your kind help.

The PA5 is new, and as such unproven. So it might be a risk. Or not. We don’t really know. Some people have had issues, but issues often get over represented on these forums.

I have been happy with my E10s, L30, PA5. I’m driving old three ways with 12” woofers. No distortion, no problems even though I’m doing it SE. I used my PA5 with Elac Debut 2.0 5.2 floorstanders and it had no problem driving them (though they were about 4-6 dB quieter than my Pioneers.

I think the PA5 is a benchmark for its price point. My budget allows me the risk, but I don’t think it is anywhere near as large as the forum would have you believe. There has been a ton of unsupported push back against this amp.

 

[BoredErica]

Saying it's the power supply without expert analysis as PMA said is foolish/premature. Need someone to look at it closely. Also there are people who've had issues 2-3 months in, some of who left the amp on all day.

One problem with the poll is the problem does not tend to rear its ugly head at start of use. Here we don't know average ownership time for pa5 among people who have vs do not have problems which can skew the results.

 

[E-Lint]

Thank you iPunch. I think I'm ready to run the risk and lean on John Yang's good reputation. In the never ending debate about which company may be *best*, if you were contemplating an entirely new stack would you tend (won't hold you to it) to lean Topping, SMSL or other especially as regards reliability/longevity? I'm just so impressed with Topping I fear I may be blinding myself a little.

 

[antcollinet]

Laptops are different than amplifiers. In a laptop the brick is basically a battery charger with almost no inrush current. This is not the same for an amplifier or other electronic device with large reservoir capacitors. It's not AC-on AC-off that's the problem, it is that large inrush of current needed to charge reservoir capacitors that causes the issue.

AND ... I'm not the only person here talking about this ... scroll back to post #50.

I get that you don't get it ... the problem appears to be that you don't get that you don't get it.

Your statement was that

this is a well known issue with ALL power bricks.

In any case the design of the power brick is the same. A switched mode power supply - it still has bulk capacitors internal to the PSU that need to be charged.

And again you are making extraordinary claims (ALL power bricks will fail if regularly switched on and off) without any data to back it up. You say it is well known - show the articles to back this up, they should be easy to find. Or just show the data YOU are using to base your statements on.

Surely you have data to base such a generalisation on - or you wouldn't say it. Would you?.

If in reality this were happening I would expect it to be all over the internet. It isn't. I would expect everyone here would already be aware of it. They aren't.

Show the data. Show the evidence. Or your claims are just assfax.

 

[Deleted member 46664]

If a first posting new guy could jump in here for a bit of advice...I'm just getting back involved in the hobby after many years. The many reviews of the PA-5 and other things Topping had led me to wish to use it as the cornerstone of an all Topping stack. Now you guys have me nervous and I'm wondering if I should either pause or go another way entirely.

Just to show you how far behind the power curve I've been for awhile I am coming from a 12 year old NR-626 Onkyo AVR. I'm looking at *mid-fi* separates system that is somewhat future proof. After getting bleary-eyed trying to assess the different (myriad) DACs I am currently settled on the E50/L50 combo with the aforementioned PA-5. The M50 streamer appeals to me also even though the strange connections put me off a bit and needs more thought.

Existing speakers are ELAC UB52 (perhaps to be upgraded later - too new now) and I am getting set to rebuild a 23 year old set of Infinity Overture 3s for another room (interestingly I think Andrew Jones may have hand in them as well).

So the question I would put to you: is the PA-5 still a reliability question mark? I'm already tempting fate by getting multiple boxes at once so I see that risk. Final question: will the PA-5 have any problem for the UB52s? Or worse, would such a pairing contribute to an early demise for the PA-5?

Apologies if I have come in at the wrong place and time. I thank you for your kind help.

I was all set to order the PA5 until this stuff showed up. Now I will wait to see the outcome.
In my thinking there's no point buying something rather expensive for what it is, if there's a question mark behind it.

 

[Deleted member 46664]

Surely you have data to base such a generalisation on - or you wouldn't say it. Would you?.

If in reality this were happening I would expect it to be all over the internet. It isn't. I would expect everyone here would already be aware of it. They aren't.

One example .... https://www.tomshardware.com/news/why-power-supplies-fail-psus,36712.html

"Overview
To summarize, high quality PSUs can fail for the following reasons:

• Broken MLCC components
• Long mounting PCB screws
• Damaged ICs and FETs because of soldering-wave issues
• Careless soldering jobs/repairs
• Cracked PCBs
• High inrush currents
• Creepy-crawlies
• High surge voltages"

And one from right here... posted in 2019...

SMPS supplies are rubbish

8x24" LG LED monitors used in our offices. 4 of them on a single computer (quad screens) used 4-5 hours a day, the other 2 in 2 pairs on other PCs that see 1-2 hours per day. 12 months old approx. They started failing 6 months in and now 5 out of 8 PSUs have died. We are only talking 23-32 Watt...

www.audiosciencereview.com

There are dozens more....

Show the data. Show the evidence. Or your claims are just assfax.

Hint ... just because you don't know about something doesn't mean it isn't true.

 

[Deleted member 46664]

I have no idea if you are right or wrong on this. This is because you’ve cited zero evidence, except a post that also cites no evidence. You hypothesis sounds reasonable to me, and you seem like you know what you are talking about, but if you want to convince others here, you will likely need to cite something that goes beyond anecdote.

See post #72, just above this one.

 

[antcollinet]

One example .... https://www.tomshardware.com/news/why-power-supplies-fail-psus,36712.html

"Overview
To summarize, high quality PSUs can fail for the following reasons:

• Broken MLCC components
• Long mounting PCB screws
• Damaged ICs and FETs because of soldering-wave issues
• Careless soldering jobs/repairs
• Cracked PCBs
• High inrush currents
• Creepy-crawlies
• High surge voltages"

And one from right here...

SMPS supplies are rubbish

8x24" LG LED monitors used in our offices. 4 of them on a single computer (quad screens) used 4-5 hours a day, the other 2 in 2 pairs on other PCs that see 1-2 hours per day. 12 months old approx. They started failing 6 months in and now 5 out of 8 PSUs have died. We are only talking 23-32 Watt...

www.audiosciencereview.com

There are dozens more....



Hint ... just because you don't know about something doesn't mean it isn't true.

A few individual examples of power supplies failing IS NOT DATA supporting your statements (unless you base your opinions on anecdotes). Of course power supplies fail. Of course there are reasons power supplies fail. All equipment does, and all equipment has.

If i were to show you examples (for example) of laptops failing, and then made the extraordinary claim that all laptops will fail if allowed to run at 100% CPU for more than 10 minutes a day, you would probably (rightly) be sceptical. I would have to show significant examples of laptop failures, together with evidence they failed because of high CPU load before anyone would believe me. I would probably have to provide test results showing 100% failure rate on a large number of devices subject to 100% load before anyone would credit "all these things" type statements.

You are making a similarly un-evidenced claim that ALL power supplies will fail early if they are switched on and off at the mains. That would result in HUGE field failure rates. To have data for that you will need to not only show *significant* numbers of power supply failures, but ALSO show they failed due to mains cycling at 1/day type rates, rather than any other reason (eg capacitor plague type problems)

Just by way of example - from the thread you linked, a possible (and most likely) conclusion:

SMPS supplies are rubbish

A conclusion could well be: Some SMPS are rubbish, some are excellent, most work just fine for many years but not all of them. It all depends on manufacture and usecases. SMPS are generally cheaper, lighter, more efficient, smaller and are regulated. disadvantages could be mains leakage and HF...

audiosciencereview.com

And the conclusion of @restorer-john (the OP, and one who knows of what he speaks) in that same thread:

SMPS supplies are rubbish

A conclusion could well be: Some SMPS are rubbish, some are excellent, most work just fine for many years but not all of them. It all depends on manufacture and usecases. SMPS are generally cheaper, lighter, more efficient, smaller and are regulated. disadvantages could be mains leakage and HF...

audiosciencereview.com

It's the degradation of the electrolyte in the internal capacitors. They run hot, way too hot

So - not all SMPS. And in this thread you quoted at least, capacitor degradation, not inrush.


So - if you want to have any credibility to your claims, you need to show they are justified. NOT just that some SMPSs fail (no surprise there) but that ALL will when subject to being switched on daily at the mains. Or at least a huge failure rate specifically attributed to this cause.

You've come to this forum, and presented yourself as an authority on all things audio (that is at least what you seem to be trying to do to me). But this forum is about science, engineering and, most of all evidence over subjective opinion. If you are going to make sweeping (and extraordinary) generalisations about *anything* you need to be prepared to back them up with that evidence.

With that - I am out.

 

[Deleted member 46664]

A few individual examples of power supplies failing IS NOT DATA supporting your statements (unless you base your opinions on anecdotes). Of course power supplies fail. Of course there are reasons power supplies fail. All equipment does, and all equipment has.

I give up ... you are no longer discussing an issue. Now you are just trying (rather desperately) to be seen to be right.

I will bet you 3 manhole covers (Already positioned on your street for easy collection) that if restorer-John sent me those dead supplies, it would turn out that the input diodes have either shorted or gone open. You see that's the weak link... those diodes take the full brunt of the inrush every time you turn the AC on.

The company I worked for (as service manager, I might add) saw hundreds of failed power supplies... almost always because people were AC cycling them, under load, either in power bars or by unplugging them.

These mini-amps with their "always on" bulk supplies increase that current inrush substantially. I have a couple of TPA3116 amps here where the initial rush of current when connecting can reach 10 amps. Do you really think that's a good thing for a 4 amp supply? How often do you expect it to endure that?

And no... the the ASR thread did not conclude "capacitor degredation" ... in fact it ended with no conclusion.

 

[pma]

High inrush currents

That's why I have an inrush limiter circuit in my PMA-NC252MP ("soft-start" circuit)

PMA NC252MP power amplifier

Real designers know the issue. I have also consulted it with Hypex tech. dept. and it was allowed to be used.

 

[antcollinet]

... Now you are just trying (rather desperately) to be seen to be right.

....

I can be neither right nor wrong. I am not making a claim. I am not even claiming you are wrong. I have no data, and in any case, proving a negative is tricky.

I am sceptical of your claim for obvious reasons. I am concerned because you are advising others how to use their kit based on what appears to be an unfounded claim. I am simply trying to point out to you the need to back up your claims with some sort of decent evidence. So far you have failed to do so.

 

[Deleted member 46664]

Real designers know the issue.

Exactly.

 

[Deleted member 46664]

I can be neither right nor wrong. I am not making a claim. I am not even claiming you are wrong. I have no data, and in any case, proving a negative is tricky.

I am sceptical of your claim for obvious reasons. I am concerned because you are advising others how to use their kit based on what appears to be an unfounded claim. I am simply trying to point out to you the need to back up your claims with some sort of decent evidence. So far you have failed to do so.

My advice is to connect amp and supply and plug it into a live outlet then use the switch on the amp to put it into standby when not in use. (You know ... as the manufacturer intended)

1) If SMPS failure is a non issue, this will result in no change.
2) If it is the issue this will result in reduced failures.
3) In neither case will it make the situation worse.

So, rather directly ... what is your problem?

 

[Fleuch]

Obviously it is the transient voltage and current switching response of both the power supply and the amplifier that gives rise to the argument of whether or not power supply design specifications are adequate. Without the circuit designs to hand, it is impossible to predict what transient current and voltage levels are in any particular product. Another completely unknown factor is the point on the supply waveform when the devices are connected or disconnected from the mains supply - switching at the waveform peak will produce different transients than at, say, zero crossing. Power supplies must have adequate tolerances to work reliably based on peak values, rather than steady state or RMS values.

It is more than reasonable to agree that when a large, probably discharged, capacitor is connected to the supply there will be a significant transient current. The components in both a power supply and amplifier must have specifications that take this into consideration, so the transient rating is as important as the steady state rating, particularly where the power lines "see" large capacitance.

It is also reasonable to accept that empirical evidence, based on experience over many years, is valid.

Two points:

• the use of a soft start device is an excellent and eminently sensible precaution; can anyone provide link(s) to a supplier?
• the most recent Topping device, the M50 Digital Music Player, requires a 5V power supply but there is no 5V power supply "in the box".

Perhaps Topping also has problems with power supplies or just wants to reduce costs. However there is much to be said to have an SMPS brick designed and matched to the device it will be used with. The need to purchase a Topping P50 Linear Power Supply to pair with the M50 is a consumer turn-off, when most Topping devices come with a power supply "in the box".