• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Topping PA5 II Stereo Amplifier Review

Rate this stereo amplifier:

  • 1. Poor (headless panther)

    Votes: 15 4.3%
  • 2. Not terrible (postman panther)

    Votes: 19 5.5%
  • 3. Fine (happy panther)

    Votes: 98 28.3%
  • 4. Great (golfing panther)

    Votes: 214 61.8%

  • Total voters
    346
Select retailers are currently selling the Topping Audio PA5 II amplifier for $199 and the PA5 II Plus amplifier for $259

 
Hi, I'm considering buying this amp for a pair of speakers from an old audio tower. The speakers' specs are 8Ω with maximum input power 70W.
Should I get the regular or the Plus version?

At first I thought about getting the Plus version, but I've seen some specs that mention the only difference in power output being @ (max 85W @8Ω for both models?). That would mean paying the extra $50 for the Plus would be a waste, no?

EDIT: Looking thorough this review again and the graph shows max power @8Ω = 53W... (So the link I mentioned above is not to be trusted 100%.)
I would assume the Plus version could go up to ~70W, which seems in line with the price upgrade.? (And a better fit for my speakers.)
 
Last edited:
Hi, I'm considering buying this amp for a pair of speakers from an old audio tower. The speakers' specs are 8Ω with maximum input power 70W.
Should I get the regular or the Plus version?

At first I thought about getting the Plus version, but I've seen some specs that mention the only difference in power output being @ (max 85W @8Ω for both models?). That would mean paying the extra $50 for the Plus would be a waste, no?
Well maybe. But you might have other speakers later on...
 
Well maybe. But you might have other speakers later on...
Hi, thanks for the reply.
Maybe, but I'm not really planning to change them in the short term. Hopefully they keep working for a long time.
I just need something small on my desk that can amplify the sound from my DX3Pro+ without that annoying hiss.
 
Hi, I'm considering buying this amp for a pair of speakers from an old audio tower. The speakers' specs are 8Ω with maximum input power 70W.
Should I get the regular or the Plus version?
Regular.

At first I thought about getting the Plus version, but I've seen some specs that mention the only difference in power output being @ (max 85W @8Ω for both models?). That would mean paying the extra $50 for the Plus would be a waste, no?
Correct.

The only difference with the Plus is a higher current power supply.

With 8Ω speakers, the PA5II is voltage-limited, not current-limited, so the extra current capability of the bigger power supply cannot be put to use.

EDIT: Looking thorough this review again and the graph shows max power @8Ω = 53W... (So the link I mentioned above is not to be trusted 100%.)
The link above, and by extension Topping's official specifications, can definitely be trusted.

It's just that Amir and Topping are measuring different things, and therefore get different results.

Amir specifies output power "at the knee", whereas Topping specify output power at 1% THD (the usual way).
 
With 8Ω speakers, the PA5II is voltage-limited, not current-limited, so the extra current capability of the bigger power supply cannot be put to use.
That's the piece of info I was missing.

Thank you very much.

Amir specifies output power "at the knee", whereas Topping specify output power at 1% THD (the usual way).
What does "at the knee" mean?
 
What does "at the knee" mean?
Topping PA5 II Stereo Amplifier Audio Balanced Power 8 ohm Measurement.png

It's the point on the THD+N vs Power curve at which the Amp first shows signs of clipping.

In the graph above, it's marked by the blue cross hair.
 
View attachment 388125
It's the point on the THD+N vs Power curve at which the Amp first shows signs of clipping.
The only difference with the Plus is a higher current power supply.
With 8Ω speakers, the PA5II is voltage-limited, not current-limited, so the extra current capability of the bigger power supply cannot be put to use.

Just to make sure I understand this, the output power "at the knee" of the Plus model would not be much/any higher than that of the Regular model when driving 8Ω speakers. Correct?
 
Hi, I'm considering buying this amp for a pair of speakers from an old audio tower. The speakers' specs are 8Ω with maximum input power 70W.
Should I get the regular or the Plus version?

At first I thought about getting the Plus version, but I've seen some specs that mention the only difference in power output being @ (max 85W @8Ω for both models?). That would mean paying the extra $50 for the Plus would be a waste, no?

EDIT: Looking thorough this review again and the graph shows max power @8Ω = 53W... (So the link I mentioned above is not to be trusted 100%.)
I would assume the Plus version could go up to ~70W, which seems in line with the price upgrade.? (And a better fit for my speakers.)
@staticV3 is right.

The TPA3251 chip has a max Voltage input of 38V. Both PSU versions are 38V. And the stronger one is only 0.8A more (3.2A vs 4A). IMHO it's not worth the 50usd
ASR and Archimago power measurments between the 2 models, show almost same power at THD+N -60db (0.1%) at 8 Ohm

I own the PA5ii+ and I really love it.
The less current of the small PSU, is not going to make a real difference, unless you have difficult 8 Ohm speakers or you listen very loudly, some bass rich music.
If I was to choose now between the 2 models, I'd take the regural one.

Anyway, if someone has the psychological urge to upgrade PSU, there are way stronger ones at 38V for that money.
 
Last edited:
Can I order PA5 power supply only? Unfortunately, mine died. I found one from audiophonics but am looking for a US seller at least for now.
 
I bought the regular PA 5 II. If you're interested - the 70w/ch of the Plus version vs. 53w/ch of the standard version only gains an extra 1.2dB of SPL headroom, so not worth it (Power gain = 10 log(70/53)).

Also, -40dB on the SNR graphs is the 1% distortion mark.
 
The PA5II case seems to run about 33 degrees C (about 38 internally as far as I could point my "gun" without removing the case). This seems to be consistent with the Fosi BT30D Pro I also have (dual TPA3255 based).

My TPA3250 unit runs a bit cooler (twenties) (Aiyima)
 
Hello. Help needed!
Connecting RME ADI-2 DAC FS to Topping PA5 II+
Which fixed volume in RME, which output level can I select to match Topping input level?
for RCA unbalanced I've set +7dBu
not sure fror XLR

Thanks
Stefano
 
Hello. Help needed!
Connecting RME ADI-2 DAC FS to Topping PA5 II+
Which fixed volume in RME, which output level can I select to match Topping input level?
for RCA unbalanced I've set +7dBu
not sure fror XLR

Thanks
Stefano
With the PA5II volume turned all the way up, you can only input 2.6Vrms (=10.5dBu) before the Amp clips.

If you reduce the volume on the PA5II enough, then you can likely max out the ADI-2 volume without clipping.
 
for RCA unbalanced I've set +7dBu
o dBu = 0,7746V RMS and, by definition, given a value Vx expressed in volts RMS, its correspondence in dBu is:

20 * log(Vx/0.7746)

So, for +7 dBu you get a V max of 1.73 V RMS. According to @staticV3, this output level will never clip the amp, no matter how loud the ampifier volume is set.
 
Back
Top Bottom