Topping PA7 Plus Amplifier Review

[terrys999]

I had 2 pa5s both died, rustling leaves ect, this hapened months ago.
Since then I bought a pa5 from a mate, took it apart, sat a fan 3 ins above without the cover.
It’s been running for seven months constantly. Never turned off and it’s still fine.
I did this to prove a point that the pa5s got too hot.

 

[amirm]

Btw

They have my money and I don't have a working amp. Not sure how it's as hard on them as it is me. :-\

Sorry if this is too much venting. I'm done.

Send me a message and I will ship you my PA5.

 

[amirm]

How is volume control implemented? Is it an analog pot? Are the two channels digitally balanced or is there channel drift?

It is analog pot. Matching is excellent at max value as you see in the measurements. I did not test it at lower levels. While I run channel matching for headphone amps, it is not as critical for power amps.

 

[Ziroz]

It shows very well that in this application a DC power supply can be a ~few feet from the amplifier section and the test results prove that to be effective.

True, but this is really killing the eye-fi factor of this amp, they could do a two box design and put the power supply in a seperate metal box.

 

[Doodski]

True, but this is really killing the eye-fi factor of this amp, they could do a two box design and put the power supply in a seperate metal box.

For sure and make sure there is enough AC cable to get to the outlets further away.

 

[Sokel]

True, but this is really killing the eye-fi factor of this amp, they could do a two box design and put the power supply in a seperate metal box.

They could but the premium added would go even closer to LA90D's price which is not that far (200$ is already not really far considering it's a power amp).

 

[MacCali]

Topping uses third-party lab to do all testing for their products. They have certificates on their site. This includes CE.

That’s grand, I’m glad to hear. I’ve had no major issues with topping. But you see some of those cables, standard issue, power plugs etc from eBay and what not with these ratings and you only see CE and that definitely makes me skeptical after finding out a company can certify its own equipment with no true checks

Just like manufacturer measurements which come out to be false.

Personally I don’t think those ratings have anything to do with a products failure, merely the cabling or the external power supply failing and catching fire or worse. Just to be clear it’s not topping I am attacking.

 

[Ra1zel]

An interesting filter is implemented which sharply reduces load dependency:

How is this acceptable

 

[MacCali]

John Yang of Topping described the PA5 failure root cause in post #50.

Topping PA7 Plus Amplifier Review

Thanks for the review. For a little more (~430 usd) I would definitely get an NC252MP based amp like the Nord below (link measurements from KJF). Better high frequency behavior, more power, internal power supply...

www.audiosciencereview.com

There you go, so purchasers need to be on top of this either by rectifying the issue or monitoring it closely to see when failure will be near

 

[EJ3]

XLR are worth it for the positive locking connection they offer.

No pets, no children under 36, 1 wife, and my mother, I have never even heard that one of my friend's RCA plugs ever came loose, much less my own.

I have run 100 ft long snakes on professional use in clubs and concerts, 100% in those applications, RCA's would come loose.
In my home, they are hooked up one time and inspected for looseness, fraying, whatever, annually.
I have also never had a grounding issue.
Although many of my friends have (& we have spent a lot of time finding and fixing them)

& it's not like I only have a few pieces of gear hooked up:
2 higher end TT's, 2 Reel to Reels, 2 older higher end cassette decks, an AM/FM tuner, 2 SONY CDR machines, 1 modified (for region free) oPPo 205 UDP, all running into 2 APT/Holman Preamps, which run into 3 NAD 2200 amps (1 bridged mono L channel, 1 bridged mono R channel for each Dahlquist 905 & 1 running stereo at 2 OHM's into a pair of custom bass cabs.
Maybe I am doing something wrong, as I have never had an issue with an RCA connector coming loose. I know some people that have but, knowing them & their families, I am not surprised that it happens to them.
I have had some that were loose from the get/go but I immediately discarded them.

 

[xaxxon]

Btw

Send me a message and I will ship you my PA5.

Thanks, but seriously I don't want it. Buckeye is my new friend and I have more channels of amplification than I need at this point

But I would like topping to do right by their customers and take back PA5's from anyone who wants their money back as well as get their vendors under control. If you're going to do business in a country (talking to you aoshida) you should have a presence there or be VERY upfront about the warranty process and costs associated. And obviously no telling people to lie on customs forms.

 

[Ra1zel]

Sorry people but I don't get the fascination here, what I see
- non flat frequency in the audio band, which imo is unacceptable for any amplifier
- distortion in high frequencies closer to a tube amp than any solid state class A or AB that could call itself decent
- doesn't reach advertised power at 20Hz (btw power as usually for topping specified at 10% THD which is far into heavy clipping, essentially meaningless number)

I'm leaning closer to calling it a total fail but that's just my opinion.

Also the usual measurement of switching behavior is missing.

 

[Bleib]

Pretty decent overall, more impressive when you consider it's a desktop form factor amp. Plenty of power for most nearfield setups.

For most? I doubt this isn't enough for any setup.

 

[Nuyes]

Yes there are II many plans.

I hope so...!


Because I built a special rackstand for the Pa5.

....

 

[Billy Budapest]

Why then they place a symbol that has no meaning and resembles the CE mark, if not to mislead potential customers?

As I posted earlier, what you are referring to is an internet hoax. There is only one CE mark—there is no alternate Chinese CE mark that “resembles” the European CE mark. It doesn’t matter how far apart the “C” and the “E” are. It only matters that they are at least 5mm tall.

 

[amirm]

How is this acceptable

What is wrong with it? Worst case is 0.6 dB down at 20 kHz. And the peaking is small and in ultrasonics.

They have an IC platform that has this issue and they are making an attempt to make the best of it. And what is there is more than acceptable.

 

[dlaloum]

That rise of THD+N at 10 and 15Khz may be hard to hear (for older ones like me) but the 5Khz where we are sensitive is very close to be audible.
Otherwise decent power.

Thanks Amir!

When you think about it... the rise in THD @ 15Khz especially the 3rd harmonic... which would be 45kHz... and as we can see in the frequency response sweep - we have a substantial rise peaking at 40Khz..... so that will boost anything happening at that frequency - including the 3rd harmonic of 15kHz... I wonder whether that rise @ 40Khz is also telling us something about noise up above 20kHz, and perhaps what is being measured is to some degree, that noise?

With regards to audibility - we have the noise charts which tell us noise is not an issue (well below threshold of audibility)- and with regards to harmonic distortion - the 2nd harmonic of 10kHz and 15kHz are 20kHz and 30Khz... 3rd harmonics are 30kHz and 45kHz.... even if your speaker is capable of reproducing this (and some are) - it will be at substantially reduced levels! (yes there are some rare exceptions to that too...) - and even then, only the most youthful among us, or the rare keen eared ones, will be able to hear those frequencies (including 20kHz.... most adults can't hear that high either!)

To a substantial degree, these are academic measurements, much like the SINAD battles (!), which demonstrate engineering rigor, rather than anything with an actual audible impact. A smart engineer might well opt to trade off this sort of inaudible flaw, for a reduction in manufacturing cost, or an improvement in some other more audible aspect of performance.

This little amp is putting in a rather exemplary performance, with the only proviso in my mind, being its limitation when speaker impedance drops to 2 ohm (a concern I have given my speakers)

 

[dlaloum]

Question - with regards to the 2ohm measurement going into protection, how long was it run before dropping into protection mode?

 

[okok]

Thanks, but seriously I don't want it. Buckeye is my new friend and I have more channels of amplification than I need at this point

it's fine, fool once or fool twice it doesn't mattet, as long as being fanboy-ish

 

[kemmler3D]

For most? I doubt this isn't enough for any setup.

If you have 8 ohm speakers, mostly listen to classical, want loud peaks, and are somehow using nearfields that are in the 85dB/w range, you might actually want all 100w, which gets you about 109dB SPL. And, if you are trying to squeeze a lot of low bass out of a sealed monitor, you can probably max this amp out easily. A Purifi 6.5" 8ohm can take 250w, for example, and is a popular driver for high-end monitors.

I agree that unless you are somewhat exacting about your peak SPL and don't have inefficient speakers, this is enough for most uses.