Topping PA5 Review (Amplifier)

[Lambda]

@pma thanks for the link!
i would like to see this measurements for this amp compared to an Class AB

Also this looks like it would be a nice addition to the measurements:

 

[F1308]

Jumped straight to stage 5

Without first thinking on the silver option...?

 

[SylphAudio]

CCIF IMD 19kHz + 20kHz for TPA325X comparing non-PFFB to PFFB is available in this document.

Expect better figures for this amp compared to the graphs in the document.

https://www.ti.com/lit/an/slaa788a/slaa788a.pdf?ts=1638887113361

 

[douede]

For those commenting on the price, I had also hoped that this amp would come in at the $300 or lower price point, as I mentioned on the pre-review thread. However, that was just a hope--not an analysis of what it should cost. As Amir already said, this amp might well have been $50 cheaper if it had been released a year ago.

Nevertheless, 65$ for this
or 110$ for this
or 85$ for this
Let's just imagine the last two with upgraded engeneering & parts : ? $

 

[Lambda]

CCIF IMD 19kHz + 20kHz for TPA325X comparing non-PFFB to PFFB is available in this document.

Expect better figures for this amp compared to the graphs in the document.

You can't realy compare them since they used different inductors and different feedback

 

[SylphAudio]

You can't realy compare them since they used different inductors and different feedback

Yes but you'll have an idea of the baseline performance of the reference amp.

 

[Reddy]

It is not about opinions but about audio science.
Therefore, the twin-tone imd measurement should not be missing.

 

[Lambda]

the twin-tone imd measurement should not be missing.

don't relay care abut 18k and 20k or 19k and 20k.
But some form of this test is a must especially for a class D

Since most Class D Amps used cheap non linear output filter inductors
and some even uses extremely non linear ceramic capacitors

 

[sarumbear]

Those who have bought PA5 could ask Topping to disclose the Class D chip used in this amp.

After all, they are the owners of PA5 and they may well have the right to know from Topping what chip they used in it. Right? Or am I missing something?

This may well put an end to the never-ending speculation regarding the chip model.

Try asking the recipe of the Coke

 

[SylphAudio]

don't relay care abut 18k and 20k or 19k and 20k.
But some form of this test is a must especially for a class D

View attachment 170898

Since most Class D Amps used cheap non linear output filter inductors
and some even uses extremely non linear ceramic capacitors

PFFB alone cannot do wonders if the output inductors are crappy to begin with. To achieve this level of performance, topping of course have used the best performing ferrites.

Though I think they've sanded the inductors to hide the brand that they've used. Since consumers now are brand conscious, it will reduce the perceived value of this amp if they see chinese branded inductors. If topping have used wurth inductors, they will definitely flaunt it.

 

[Lambda]

Try asking the recipe of the Coke

The ingredients are listed on the bottle

We already had this and it was normal!

Why not hold Manufactures responsible to this standards?

 

[Dj7675]

Is there a dedicated thread created for those that disagree with testing methodology used by Amir and/or requesting additional amplifier tests? I know there is such a thread for headphone and speaker measurements but not sure if there is one for amplifier tests. If so, shouldn’t these types of posts go there instead of cluttering this and other amplifier reviews?

 

[howard416]

don't relay care abut 18k and 20k or 19k and 20k.
But some form of this test is a must especially for a class D

View attachment 170898

Since most Class D Amps used cheap non linear output filter inductors
and some even uses extremely non linear ceramic capacitors

What do you get from that, that you don't get from the 32 tone test? The 32 tone test might not correlate exactly with "music", but it's definitely more of a real world test (and IMO more useful) than 18+19 kHz.

But, if you use the amp with signals that have the majority of their content in the >10 kHz register, sure, it would be indispensible for you.

 

[restorer-john]

We already had this and it was normal!

Why not hold Manufactures responsible to this standards?

Service manuals and schematics have always been controlled somewhat, but usually could be obtained (at a price) through approved channels. The internet and widespread adoption of the PDF has allowed distribution to a wider audience at a lower cost.

Proprietary technologies or hybrid potted modules have always been a grey area and manufacturers have sought to keep their trade secrets for as long as they can. That's fair enough.

Plenty of schematics stop at a greyed-out box and have done for many decades. That greyed-out box is their IP.

The internal schematics of opamps, hybrid STKs, the code used in dedicated uPs etc aren't published except perhaps with no detail. I remember reverse engineering some Sanken power output modules in the 1980s to repair otherwise landfill amplifiers.

 

[Labjr]

Service manuals and schematics have always been controlled somewhat, but usually could be obtained (at a price) through approved channels. The internet and widespread adoption of the PDF has allowed distribution to a wider audience at a lower cost.

Proprietary technologies or hybrid potted modules have always been a grey area and manufacturers have sought to keep their trade secrets for as long as they can. That's fair enough.

Plenty of schematics stop at a greyed-out box and have done for many decades. That greyed-out box is their IP.

The internal schematics of opamps, hybrid STKs, the code used in dedicated uPs etc aren't published except perhaps with no detail. I remember reverse engineering some Sanken power output modules in the 1980s to repair otherwise landfill amplifiers.

I believe STK modules were monolithic ICs which were made to reduce cost of building receivers etc. Not necessarily to conceal IP. There was no need to reverse engineer them. There were spec sheets with schematics diagrams available. At some point there were 3rd party substitutes but I thought they were mostly bad quality.

 

[misterdog]

Try asking the recipe of the Coke

 

[hansik]

And they say they are selling a lot...

DUE TO VERY HIGH DEMAND, THE AHB2 IS SHIPPING WITH A 3 WEEK BACKORDER. PLACE YOUR ORDER NOW AND WE WILL SHIP IN THE ORDER RECEIVED.
WE SHIP ALL ORDERS IN THE SEQUENCE RECEIVED
WE RECOMMEND PLACING AN ORDER BEFORE THIS NEXT RUN IS SOLD OUT. WE HAVE BEEN WORKING HARD TO INCREASE OUR PRODUCTION, BUT DEMAND HAS BEEN GROWING RAPIDLY.

Benchmark AHB2 Power Amplifier

Benchmark's new AHB2 Power Amplifier - "The Quietest, Cleanest Audio Amplifier on the Planet"

benchmarkmedia.com

Standard marketing. I dont think at that price they can’t follow

 

[misterdog]

I think they've sanded the inductors to hide the brand that they've used.

It's not difficult to wind an inductor, maybe they have wound their own and only the conspiracy theorists, who are 'audio enthusiasts' see a sanded off part number.

Hardly magic.

Running your own business on the other hand, with the attendant R+D, marketing, manufacturing and sales is far more complex.
Though some see it as simple as winding an inductor.

 

[Lambda]

What do you get from that, that you don't get from the 32 tone test? The 32 tone test might not correlate exactly with "music", but it's definitely more of a real world test (and IMO more useful) than 18+19 kHz.

But, if you use the amp with signals that have the majority of their content in the >10 kHz register, sure, it would be indispensible for you.

You get higher amplitude.
Tests dont need to be "real world like" they need to be reviling. and we need to have the knowlage to kow how to translate re results to real world.
SINAD a 1Khz is also not real world at al but it tells a lot.
You might not get a lot of >10 kHz periodic high amplitude signals but you sure get a lot of fast rise time signal wit high amplitude.

but usually could be obtained (at a price) through approved channels. The internet and widespread adoption of the PDF has allowed distribution to a wider audience at a lower cost.

I have lot of old gear that came with schematics.
a portable TV from the 90s with the schematics in the normal user manual including waveform diagrams at test points.
also that modern Sony camera in the video.
And if buy super expensive test gear i also get a lot of this documentation.

It's not difficult to wind an inductor, maybe they have wound their own and only the conspiracy theorists, who are 'audio enthusiasts' see a sanded off part number.

Not the coil but the material in it is the interesting part.

 

[voodooless]

It's not difficult to wind an inductor, maybe they have wound their own and only the conspiracy theorists, who are 'audio enthusiasts' see a sanded off part number.

Why would one then make an exact copy of Würth inductors and then file off the markings?

And I would also disagree about the complexity argument. These coils are one of the instrumental parts in the performance of the amp. If they were so easy to make, somebody else would already have done it. These things are made to be small, handle loads of current and have a very high saturation point with good shielding. That is very far removed from your hand wound inductor.