Topping PA5 Review (Amplifier)

[restorer-john]

... and it also means you get more years or decades of reliable function. Depends what you are seeking for. If it is a toy which you need to change every 6 months to be "in" on the social network, then these small undersized boxes are the way to go.

It's a case of old heads can't be put on young shoulders, Pavel.

Modern day, young audiophiles need to have their own journey of discovery. They will learn (hopefully) that the cheap, tiny, poorly ventilated, heat producing products they are clamouring to buy today, will be in landfill in short order. Nobody will repair them.

They are faux eco-warriors, using paper straws, re-usable shopping bags and hanging out at farmer's markets on the weekend, professing a 'sustainable' vision midset. But their brown goods are being turned over (often for no good reason) at a rate never before seen in the history of the world, creating e-waste on a scale that is just criminal.

Hypocrisy, much?

 

[Raindog123]

Modern day, young audiophiles…

 

[dwkdnvr]

Well now we know. So how is it that the amp won't function normally if the IC is replaced with another one? (Said in Post #1808)

Well, that's the question, isn't it? The PA5 seems to be 8-10dB better than a typical TPA325X amp, at least below 5kHz. But how? Ideas for approaches that would either not work or work less well with an off-the-shelf drop in:

- a customized approach where the feedback/feedforward circuit is individually tuned for the specific chip used
- binning of parts. Maybe they're measuring and only using the best x% of chips which fit their circuit or performance thresholds
- custom run / clone. Maybe it's not a real TPA325X but instead a customized/altered version or a 'semi-clone' that has different characteristics, and the circuit is tuned for them
- Misdirection. Maybe it will work just fine and John was engaging in a bit of marketing.

There are probably other options, but these are the ones that occurred to me. All of them have problems, I think. e.g. #1 and #2 it's not at all clear that there is enough variability chip-to-chip that this would be relevant. #3 seems unlikely that Topping would be involved in ripping off IP, and I'm not sure TI is in the business of custom altered designs. #4 is basically calling John a liar which I don't think he is.

#2 might be a viable explanation if this is in fact a composite topology with an opamp controlling the feedback loop. It's possible that the timing constraints for this are tight enough that not all chips can meet it, so they have to test. This might also include #1 with custom feedback circuit values based on the individual chip.

Or, maybe we'll never know. (for a while, anyway. someone on DIYAudio is almost certainly going to crack one open to try to see how it works)

 

[xrk971]

Thanks for confirming this visually. Back in post 240 I predicted it was 3251 based on the shape of the distortion vs frequency curve and the noise and distortion figures assuming PFFB with modified level of extra feedback.

Topping PA5 Review (Amplifier)

Very nice! Especially when you consider its target use (where "lack" of power doesn't matter as much and reachable volume control is a must). Now, I just want to see what the generalist version will look like (integrated main, no volume control, moar power). Kudos to Topping for pushing...

www.audiosciencereview.com

The laser rubout wasn’t quite deep enough.

 

[TheWalkman]

This is the same chip found in the Aiyima 04.

Owning the Aiyima 04, the 07 and now the Topping, I had preferred the 04 to the 07. Can’t really quantify it: clearer sound? It just sounded better to me.

With five days of listening to the Topping, I like it but really question if it’s worth 5x the price of the 04 (with a decent power supply).

When @amirm tested the 07, it generated a high volume of posts.

Now that we know the secret sauce in the Topping is the same 3251 found in the Aiyima 04, wouldn’t we like to see an apples-to-apples comparison?

Is it just me or would others enjoy an Aiyima 04/ PA 5 shootout?

 

[nagster]

I think that unfair competitors would be able to get a PA5, determine the used chip, and reverse engineer the rest anyway. I do not think you have done damage. It is a cut-throat world where JohnYang1997 has chosen to work. The great italian hifi designer Bartolomeo Aloia once said that he stopped filing patents on circuits because other people would copy them anyway, patents are expensive, litigation even more so, and dishonest people can get away with minimal modifications...

Thank you for your concern.

If the IC is a commercial product, the model number will be known someday regardless of my involvement.
But, the faster the evidence is found, the faster the copy and chase will be, and the more effortless and advantageous the competitors will be.

Normally, I publish tear down photos without worrying about anything. This is because anyone can shoot.
When I took a picture of my PA5, I saw traces of numbers. Probably a failure of the concealment process.
I thought the endless debate of many detectives in this thread might end.
I don't know if it happened to buy a failed product that had only one, or if it was all.

However, JohnYang1997 clarified the attitude of protecting information in Post #1808. I have no intention of interfering with their correct behavior.
Either way (at least this time) the disclosure of unknown traces was my mistake.

 

[ogonex]

However, JohnYang1997 clarified the attitude of protecting information in Post #1808. I have no intention of interfering with their correct behavior.
Either way (at least this time) the disclosure of unknown traces was my mistake.

It was not a mistake. Customers have the right to know what they are buying.

 

[kiyu]

Hi Guys!

I have 2 Stupid questions, (noob question)
I got a set of beautiful bookshelf Klipsch RB-61 II Sensitivity 95dB @ 2.83V / 1m Nominal Impedance 8 ohms compatible

1) would I get enough volume with this amp?
2) in the back they are 4 connectors (2 black , 2 red) , I already got 1 black 1 red, connected to my Denon AVR, will be ok, to connect Pa5 to the other 2, right?
Please confirm
Thanks!!

 

[ogonex]

Klon Accuphase'a jest jak replika Rolexa..

You are 100% right. Accuphase craftsmanship and you pay for it

 

[ogonex]

Hi Guys!

I have 2 Stupid questions, (noob question)
I got a set of beautiful bookshelf Klipsch RB-61 II Sensitivity 95dB @ 2.83V / 1m Nominal Impedance 8 ohms compatible

1) would I get enough volume with this amp?
2) in the back they are 4 connectors (2 black , 2 red) , I already got 1 black 1 red, connected to my Denon AVR, will be ok, to connect Pa5 to the other 2, right?
Please confirm
Thanks!!

Absolutely not.

 

[Billy Budapest]

Hi Guys!

I have 2 Stupid questions, (noob question)
I got a set of beautiful bookshelf Klipsch RB-61 II Sensitivity 95dB @ 2.83V / 1m Nominal Impedance 8 ohms compatible

1) would I get enough volume with this amp?
2) in the back they are 4 connectors (2 black , 2 red) , I already got 1 black 1 red, connected to my Denon AVR, will be ok, to connect Pa5 to the other 2, right?
Please confirm
Thanks!!

Yes, you would have enough power.

No, do not connect both sets of speaker posts to your AVR and to the PA5.

 

[kiyu]

Absolutely not.

really not enough juice or what?
could you please clarify a bit? thanks!

 

[Billy Budapest]

really not enough juice or what?
could you please clarify a bit? thanks!

There would be plenty of power. The “absolutely not” remark referred to hooking two amplifiers to one speaker.

Now, there are ways to do this if you are vertically bi-amping your speakers, but I do not think think that is what you are intending to do. Instead, if you want to share one pair of speakers between the AVR and the PA5, you would have to use a speaker switcher.

 

[kiyu]

Yes, you would have enough power.

No, do not connect both sets of speaker posts to your AVR and to the PA5.

ok Thanks!
then wondering why are 4 instead of just 2?

 

[ogonex]

ok Thanks!
then wondering why are 4 instead of just 2?

one pair is connected to the tweeter and the other to the woofer. That's why you have jumpers there (short-circuiting plates)
do an experiment. take out these plates and connect your Denon to the lower terminals and then to the upper ones, then everything will be clear to you
play some music of course

 

[SylphAudio]

This is the same chip found in the Aiyima 04.

Owning the Aiyima 04, the 07 and now the Topping, I had preferred the 04 to the 07. Can’t really quantify it: clearer sound? It just sounded better to me.

With five days of listening to the Topping, I like it but really question if it’s worth 5x the price of the 04 (with a decent power supply).

When @amirm tested the 07, it generated a high volume of posts.

Now that we know the secret sauce in the Topping is the same 3251 found in the Aiyima 04, wouldn’t we like to see an apples-to-apples comparison?

Is it just me or would others enjoy an Aiyima 04/ PA 5 shootout?

Based on a user feedback in DIYAudio, looks like the current version of the A04 already has a passive PFFB but at the expense of much much lower gain. It might get 94dB to 96dB SINAD at 5W 4 ohm. Topping PA5 is 10dB better at 1kHz SINAD, but I think amps with around 85dB SINAD score at 5W 4ohm are good already in terms of noise and sq.

For me TPA3251 has a more 'natural' sound, then TPA3255 has a cleaner sound and blacker background.

 

[ogonex]

Looks like the current version of the A04 has a passive PFFB but at the expense of much lower gain, it might get 94dB to 96dB SINAD at 5W 4 ohm. Topping PA5 is 10dB better, but I think amps with around 85dB SINAD score at 5W 4ohm is good already in terms of noise and sq.

For me TPA3251 has a more 'natural' sound, then TPA3255 has a cleaner sound and blacker background.

By the way, I will ask because I do not know: if you use the bluetooth receiver in these amplifiers from China, does the signal go through OP-amps or directly digitally enter TPA?
Thanks for answer Jlester

 

[KSTR]

It was not a mistake. Customers have the right to know what they are buying.

No.
They may have a legitimate private interest (aka curiosity) but certainly no enforceable rights. For 99.9999% of users the leaked info is still completely useless anyway.

 

[ogonex]

No.
They may have a legitimate private interest (aka curiosity) but certainly no enforceable rights. For 99.9999% of users the leaked info is still completely useless anyway.

But it is not a mistake to disclose this publicly.
Especially since the copyright in China does not exist

 

[daniboun]

This is the same chip found in the Aiyima 04.

Owning the Aiyima 04, the 07 and now the Topping, I had preferred the 04 to the 07. Can’t really quantify it: clearer sound? It just sounded better to me.

With five days of listening to the Topping, I like it but really question if it’s worth 5x the price of the 04 (with a decent power supply).

When @amirm tested the 07, it generated a high volume of posts.

Now that we know the secret sauce in the Topping is the same 3251 found in the Aiyima 04, wouldn’t we like to see an apples-to-apples comparison?

Is it just me or would others enjoy an Aiyima 04/ PA 5 shootout?

I agree, the best TPA3251 I have ever tested is the very first A04 with the TILEAR Rev 2.1 PCB. For the tiny price and minor updates, it is probably the best amp in the market.

It was supposed to be measured by ASR but the American guy never shipped it to Amir unfortunately....

I mean this one :