Topping PA5 Review (Amplifier)

[antcollinet]

Maybe. Or maybe they use ASR as a platform to improve their margins, actually scratch maybe, because they do.

Give it a rest.

How many people here are actually going to buy one of these? 10? 20? 50? 100? Whatever it is, it's not enough to sustain a manufacturing business.

The price is the price. Don't like it, don't buy it.

No one said the amp isn’t good, but you can get about the same sounding amps much cheaper.

So why don't you buy one of those instead of griping about this one.

 

[TNT]

IMHO, this thread has gone off the rails. If it was so easy to grab a fist-full of off-the-shelf parts and make a >45 watt amplifier with SINAD above 100 dB, there'd be lots of them.....

Yes, but how many does this:

https://www.audiosciencereview.com/...ements-multitone-stereo-amplifier-png.168543/

AHB2

https://www.audiosciencereview.com/forum/index.php?attachments/benchmark-ahb2-amplifier-19-and-20-khz-intermodulation-distortion-audio-measurements-png.26582/

//

 

[Georgrig]

It is, I just refuse to pay the ASR Sinad tax.

I'd very much prefer paying the ASR SINAD tax than <insert audiofool media outlet/forum name> tax. At least it is something measurable...

 

[capslock]

No,

They made a composite amp like this, replace the Lm3886 for the TPA.

View attachment 170336

What is the source of this schematic? Is it a proposal for simulation from diyaudio or a proven circuit?

Usually, composite amps have to throw away some gain at the op-amp's output. Even the Neurochrome schematics I have seen do this.

In this case here, the LM3886 and the op-amp are running the same gain, so the op-amp is effectively running at unity gain, but with a lumbering slow power amp in its loop. There are efforts at compensation, but are they really going to be viable in the real world?

 

[TimF]

Some of these comments are really nasty. A company can determine its markup and part of its markup may likely raise resources for more product development. If a Chinese company makes a dollar does that upset you? Look at the mark-ups on high end boutique products assembled in the USA. Have you looked at the prices of Bel Canto products and a host of the others.

 

[Mulder]

Perhaps in the future the threads should be divided according to the reviews so that those who want to discuss price or generally express their admiration or worship of products can do so in a thread separated from the discussion about the products' technical merits or what the measurements actually show.

 

[DS23MAN]

What is the source of this schematic? Is it a proposal for simulation from diyaudio or a proven circuit?

Usually, composite amps have to throw away some gain at the op-amp's output. Even the Neurochrome schematics I have seen do this.

In this case here, the LM3886 and the op-amp are running the same gain, so the op-amp is effectively running at unity gain, but with a lumbering slow power amp in its loop. There are efforts at compensation, but are they really going to be viable in the real world?

Composite versterker "De brainstorm" - Pagina 5 - forum.zelfbouwaudio.nl

A lot of members have been building this design.

 

[MarkWinston]

Look son, cheapskates. Cheapskates everywhere.

 

[MarkWinston]

It is, I just refuse to pay the ASR Sinad tax.



I will, when the need arises.

Again, trying to justify the cheapskate in you with high sinad numbers, like no other areas measured great. Whats with you and sinad numbers?

 

[DS23MAN]

Can we please stop this stupid pricing debate?

 

[nhs]

Few notes after getting the PA5 up and running:

The speaker binding posts are small (as you’d expect). It took quite a lot of work to get my 1.5mm2 cable into the drilled horizontal hole. Also, the depth of the 6mm plug hole appears pretty shallow. One pair of posts became a bit loose while I was trying to install cables - it feels very much like loose internal locking nuts. No complaints, but I’m going to open the amp up to tighten the nuts on the inside and have a look at other things while I’m doing it.

Hopefully there's no problem with banana plugs.

 

[daniboun]

Composite versterker "De brainstorm" - Pagina 5 - forum.zelfbouwaudio.nl

A lot of members have been building this design.

A very well known is the Modulus by Neurochrome that is a 65 W composite amplifier
If I am not wrong, it uses one channel of an LM4562 op amps.

You can check the measures here by the way :

Review and Measurements of Neurochrome Modulus-286 Amp

This is a review and detailed measurements of the Neurochrome Modulus-286 Power (speaker) amplifier Kit. It is on kind loan from company designer and member, @tomchr. It is to ship by end of this month and costs $1,299. See: https://www.neurochrome.com/product/modulus-286-kit-2/ As you may...

www.audiosciencereview.com

They measure pretty well.

 

[DanielT]

Can we please stop this stupid pricing debate?

I agree but with the addition that price vs performance is extremely interesting.

Price in itself. We have no idea why Topping put this price on this amplifier. It's just a lot of loose speculation without substance.

Supply and demand prevail. Not more complicated than that.

 

[water6]

I'm new to speakers so don't really understand most of the measurements. Is it possible to read off how much noise the amp makes from amrim's measurements when there's either 1. no input signal, and 2. a very quiet input signal fed into the amp? I'm looking for an amp for nearfield use, and am extremely sensitive to hiss and would like as little as possible in both situations.

• a SNR of 107dB @ 5W was measured. Does that mean that at 0W and at 0.001W there would still be an SNR of 107dB, so any noise would be at a level of -107dB? (edit: I guess the answer is no, because at full power the SNR is 121 dB, so therefore the SNR at 0W must be much lower)
• I beleive the first measurement, a 1kHz sine wave @ 0.5V shows noise at -120dB. Does this mean that at 0V and 0.001V noise will be at the same level (-120dB)?

 

[capslock]

Composite versterker "De brainstorm" - Pagina 5 - forum.zelfbouwaudio.nl

A lot of members have been building this design.

Thanks, I didn't know about this project.

I found measurements at this place in the thread which look pretty good but are clearly limited by the soundcard:

Composite versterker "De brainstorm" - Pagina 6 - forum.zelfbouwaudio.nl

Are you aware of more elaborate measurements? Since it does not throw away gain after the op-amp, it could potentially measure even better than Neurochrome.

Are the PCBs still available?

 

[SylphAudio]

The fact is that the PA5 is vastly quieter, so the measurements really aren't "more or less equal." Whether that difference is worth the extra $$$ is both highly subjective and very application dependent. I use A07s to drive my ambience/surround speakers -- my main L+R speakers and subwoofer are active -- and don't see spending $700USD for what would amount to little or no audible improvement as making a lick of sense in my particular situation.

Maybe a hiss measurement on the speaker output (on standardized parameters) will be nice to have in future amp measurements.

 

[Rafaille]

I'm new to speakers so don't really understand most of the measurements. Is it possible to read off how much noise the amp makes from amrim's measurements when there's either 1. no input signal, and 2. a very quiet input signal fed into the amp? I'm looking for an amp for nearfield use, and am extremely sensitive to hiss and would like as little as possible in both situations.

• a SNR of 107dB @ 5W was measured. Does that mean that at 0W and at 0.001W there would still be an SNR of 107dB, so any noise would be at a level of -107dB? (edit: I guess the answer is no, because at full power the SNR is 121 dB, so therefore the SNR at 0W must be much lower)
• I beleive the first measurement, a 1kHz sine wave @ 0.5V shows noise at -120dB. Does this mean that at 0V and 0.001V noise will be at the same level (-120dB)?

Looking at the power vs distortion graph should give you an answer.
According to measurements, if you can hear hiss coming out of your speakers you cannot blame this amp for it.
But said noise might originate from elsewhere in your system and be amplified (as it should) by the amp.

 

[water6]

Looking at the power vs distortion graph should give you an answer.
According to measurements, if you can hear hiss coming out of your speakers you cannot blame this amp for it.
But said noise might originate from elsewhere in your system and be amplified (as it should) by the amp.

Excellent, exactly what I was looking for. Thanks!

 

[ol_mcdonald]

I’m just an old country boy, and it mystifies me why such a well performing product is in such an odd form factor, have balanced TRS inputs, RCA outs and binding posts.

I know it’s been beat to death but it puzzles me. 19” rack mount it with XLR and speakON connections and increase the price $200 bucks and I’m in, and it’s still a great value.

I am curious though how it would stack up against my old Crown D75 with my Topping D90se.

 

[daniboun]

Looking at the power vs distortion graph should give you an answer.
According to measurements, if you can hear hiss coming out of your speakers you cannot blame this amp for it.
But said noise might originate from elsewhere in your system and be amplified (as it should) by the amp.

Could help :