Topping PA5 Review (Amplifier)

[bigjacko]

After my NFCA circuit got copied and supposedly patented(in China) by a different company and even there are clear errors in the patent filing, it drove me mad like no tomorrow. I of course would go extra mile protecting all the hours that went in.

Sad to see this, if patent law is not working right it can actually make negative impact. I am curious why topping did not patent it in the first place? Maybe it costs a bit but topping is selling quite a lot. Is it because the design is actually not innovative enough so you guys don't bother, but patent office mistaken it to be innovative? That probably happened a lot of times given they probably are not experts in any field.......

 

[bahamot]

I am very sorrow and feel pain hearing this.
My deepest condolences and best of understandings.
Also, my 120 minutes of applause for your achievements.
Well done.
Great work.
Lovely.
Thank you very much, indeed.

I have been on standby waiting to buy as I went following your comments on the works you were developing and announced hereabouts with a whisper, and finally did buy.

And now, tell us, please, the name of the villain so I, we, can possibly avoid becoming his customers.

Maybe Sabaj

 

[Kaval]

I've not had a lot of luck buying KFC and then demanding they tell me the secret blend of herbs and spices.

It is the same company (Topping) that publicize all the chips/opamps/XMOS etc used in its other products (such as DACs and headphone amps). In fact, Topping publicizes them as a part of its marketing blitz.

If Topping can do it for other audio products, why shy away from disclosing the chip used in PA5?

Why double-standards?

 

[SylphAudio]

Datasheet says that 1000uF is adequate in a well designed system. Assuming that it is a TPA3255. lol.

Most chinese TPA3255 units only use 100nF right at the PVDD pins because 1uF is too tall for the generic heatsink that they use. But since PA5 has flawless performance, it shows that datasheet recommendations can be circumvented.

 

[Kevinfc]

Ever hear of nakamichi power amps? Pa5 pa7.

Nope

 

[bahamot]

It is the same company (Topping) that publicize all the chips/opamps/XMOS etc used in its other products (such as DACs and headphone amps). In fact, Topping publicizes them as a part of its marketing blitz.

If Topping can do it for other audio products, why shy away from disclosing the chip used in PA5?

Why double-standards?

This is why:

After my NFCA circuit got copied and supposedly patented(in China) by a different company and even there are clear errors in the patent filing, it drove me mad like no tomorrow. I of course would go extra mile protecting all the hours that went in.

 

[Kaval]

I am not talking about the design, engineering or reverse engineering processes, I want to know the chip used in PA5.

It is Topping itself that put the pics of the internal components/chips and their design/circuit/system as part of their marketing campaign for audio products.

See, for example, here: https://shenzhenaudio.com/products/...12-dac-nfca-headphone-amplifier-pre-amplifier

 

[SylphAudio]

@amirm @JohnYang1997 Could either of you measure the Phase shift for the PA5, like in this graph for the Hypex NC400?

I think this parameter has an audible impact in the sound specially in the soundstage area. If you compare and quickly change the amplifiers with non-PFFB vs PFFB, you will notice that the PFFB one has an "ultra wide" soundstage; the non-PFFB however has a "taller and bigger bubble" soundstage. The ultrawide soundstage somehow resembles a stereo speaker with one channel polarity reversed. I noticed this first in SystemD LiteAmp PFFB IRS2092 way back before, PFFB has great definition and echo but somehow the non-PFFB sounds fuller even though the soundstage is not as wide. Though I'm not generalizing all PFFB, it depends on the implementation as to what Hypex/Purifi has demonstrated.

 

[Kuba]

It is the same company, Topping, that publicizes the chip (MA12070) used in PA3. Some may even argue that Topping is "over-publicizing" MA12070 chip in its publicity material as this chip is mentioned in several places.

Then the obvious question is: Why not for PA5?

See their marketing material on PA3: https://shenzhenaudio.com/products/...12-dac-nfca-headphone-amplifier-pre-amplifier

You already wrote that once, stop trolling

 

[TheTalbotHound]

I think this parameter has an audible impact in the sound specially in the soundstage area. If you compare and quickly change the amplifiers with non-PFFB vs PFFB, you will notice that the PFFB one has an "ultra wide" soundstage; the non-PFFB however has a "taller and bigger bubble" soundstage. The ultrawide soundstage somehow resembles a stereo speaker with one channel polarity reversed. I noticed this first in SystemD LiteAmp PFFB IRS2092 way back before, PFFB has great definition and echo but somehow the non-PFFB sounds fuller even though the soundstage is not as wide. Though I'm not generalizing all PFFB, it depends on the implementation as to what Hypex/Purifi has demonstrated.

Nice thing about phase is it can be reversed/corrected with EQ. I use RePhase to do this.

 

[restorer-john]

Nope

Go do some research.

Legendary 'stasis' power amplifiers using some licensed Nelson Pass circuit techniques.

 

[DanielT]

Go do some research.

Legendary 'stasis' power amplifiers using some licensed Nelson Pass circuit techniques.

Addition. Someone who has one that Amir can test? PA5 then vs PA5 now.

Nakamichi PA-5 Stereo Power Amplifier Manual | HiFi Engine

www.hifiengine.com

Looks like a nice machine.

Hm how can THD be as high as 0.1% at the same time as Signal to noise ratio: 120dB?

Or maybe it can. Depending on how it is measured, THD ie. S / N was high.

 

[restorer-john]

Hm how can THD be as high as 0.1% at the same time as Signal to noise ratio: 120dB?

Because signal to noise ratio is the maximum signal level in volts, referenced to the residual noise (in V), expressed in dB.

THD has absolutely nothing to do with S/N ratio.

Forget 1kHz SINAD, its a relatively useless metric.

 

[Frank Sol]

Because signal to noise ratio is the maximum signal level in volts, referenced to the residual noise (in V), expressed in dB.

THD has absolutely nothing to do with S/N ratio.

Forget 1kHz SINAD, its a relatively useless metric.

Thanks

(Edited: inserted "1kHz" per restorer-john's edit)

 

[pma]

Forget SINAD, its a relatively useless metric.

I would go even farther - it is the ASR marketing metric .

 

[restorer-john]

I would go even farther - it is the ASR marketing metric .

I edited it to 1kHz SINAD.

 

[DanielT]

Because signal to noise ratio is the maximum signal level in volts, referenced to the residual noise (in V), expressed in dB.

THD has absolutely nothing to do with S/N ratio.

Forget 1kHz SINAD, its a relatively useless metric.

Thanks John for clarifying.

Of course noise is one thing distortion another. I knew that. Blame hm no it was yesterday I drank some Glögg (Glühwein).

In any case. It would have been fun if Amir tested a Nakamichi PA-5.

 

[KSTR]

I think this parameter has an audible impact in the sound specially in the soundstage area. If you compare and quickly change the amplifiers with non-PFFB vs PFFB, you will notice that the PFFB one has an "ultra wide" soundstage; the non-PFFB however has a "taller and bigger bubble" soundstage. The ultrawide soundstage somehow resembles a stereo speaker with one channel polarity reversed. I noticed this first in SystemD LiteAmp PFFB IRS2092 way back before, PFFB has great definition and echo but somehow the non-PFFB sounds fuller even though the soundstage is not as wide. Though I'm not generalizing all PFFB, it depends on the implementation as to what Hypex/Purifi has demonstrated.

It's hard to tell what impact phase has had because it's not the only variable that has changed. Once it is the only variable, all bets are off it's unlikely anyone could detect a minor phase difference coming from amps with different bandwidths and roll-offs.

 

[restorer-john]

It's hard to tell what impact phase has had because it's not the only variable that has changed. Once it is the only variable, all bets are off anyone could detect a minor phase difference coming from amps with different bandwidths and roll-offs.

There's a cohort of people that don't believe phase variances are audible or significant.

 

[KSTR]

There's a cohort of people that don't believe phase variances are audible or significant.

I'm one of them wrt to amps at any rate, assuming non-pathological situations.

EDIT: edit non-native english speaker error in previous posts ;-)