Topping PA5 II Stereo Amplifier Review

[antcollinet]

try to measure frequency response at different power levels.

That doesn't make as much sense as the distortion/power curves already provided at different frequencise - this tells us how max power varies across the frequency range as shown below. We sometimes find that at low frequencies, less power is available.

We could also try to measure spikes at different frequencies to try to get an idea of the capacity of the amp to deliver the full energy of the original waveform. Does this make sense?

The same chart gives this information too.

What this chart shows for this amp, is that there is no reduced power at low frequencies. So there is not a weakness here. Supports the theory that the Sonos Amp is set up to boost low frequencies and you are simply used to this, so feel it lacking with a flatter frequency response.

 

[Sokel]

There can be lot of things at play between two amps.Either deliberate or not.
EQ,lack of power,load dependencies,etc.

What's shown with the recordings we have at hand is that in one occasion (in the recordings of the first post) something was at play with Sonos.
Second test showed smaller difference down low but all tests showed showed something up high,with PA5 being brighter in a very sensitive area (about 5Khz).

We can't be sure of course cause high freqs are hard to capture properly but in every recording the same thing is consistent up there.

In post #821 you can also see how the recordings of the two amps compare with the original music.

BUT all the above depends of the quality of the recordings.At least some things are consistent between them but a proper test would require a very different and probably hard to set-up rig mimicking all the conditions.

Of course all of that is irrelevant. @cptsantos 's ears made their choice and that's it.

 

[cptsantos]

There can be lot of things at play between two amps.Either deliberate or not.
EQ,lack of power,load dependencies,etc.

I agree.

What's shown with the recordings we have at hand is that in one occasion (in the recordings of the first post) something was at play with Sonos.
Second test showed smaller difference down low but all tests showed showed something up high,with PA5 being brighter in a very sensitive area (about 5Khz).

We can't be sure of course cause high freqs are hard to capture properly but in every recording the same thing is consistent up there.

In post #821 you can also see how the recordings of the two amps compare with the original music.

BUT all the above depends of the quality of the recordings.At least some things are consistent between them but a proper test would require a very different and probably hard to set-up rig mimicking all the conditions.

Yep. I did my best with my limited conditions

Of course all of that is irreverent. @cptsantos 's ears made their choice and that's it.

My initial goal was to replace the Sonos due to audio interruptions while streaming. Ordered the Wiim and the PA5 II. Tested it and was disappointed with the sound. At the same time I’ve discovered that I could downgrade the Sonos from S2 to S1 so I did it. This resulted in a lot better streaming performance and general responsiveness.
So I didn’t have a problem anymore and the new setup didn’t sound as good to my ears. The choice was simple.

 

[Xibal]

There are neutral, transparent amps. There are also amps that color/"enhance" the sound on purpose.

Ok, so how about a "sound transparent", regarding his measurements (amirm review), Pa5 II being called "bright" through other measurements (@Sokel)?

 

[Sokel]

Ok, so how about a "sound transparent", regarding his measurements (amirm review), Pa5 II being called "bright" through other measurements (@Sokel)?

We have to be careful here,that's not my measurements,it's what I see with what we have on the specific rig,everything included,amp+speaker+mic,etc.
In Amir measurements there's a tiny hint on the specific region 5-20Khz (and I mean tiny!) which by all means shows a flat amp.

Nothing suggest otherwise except of a bad sample,some strange heavy interaction with the speakers or who knows what else.

For reference that's the speaker:




Not the easiest out there but far from hard,the amp should drive it with ease.

 

[mike70]

If audiophiles like warm amps, and HiFi is just about replaying what's on the recording, why do we have "house curves" at all?

You're mixing (at least) 3 different concepts in your question, it seems to me:

- how people likes to listen to music
- what's hifi conceptually
- how sound works / is perceived in the room (acoustics)

 

[Dave Bullet]

I'm not sure why you are using music to compare amplifiers. Why not do a loopback sine or MLS sweep at least keeping the amplifier voltage at 0.5v to avoid blowing your input soundcard. Unless both amplifiers have a serious and published power non-linearities, this should show whether there is any rolloff at bass frequencies with the PA5II (i.e. defective unit / channel).

 

[Xibal]

We have to be careful here,that's not my measurements,it's what I see with what we have on the specific rig,everything included,amp+speaker+mic,etc.
In Amir measurements there's a tiny hint on the specific region 5-20Khz (and I mean tiny!) which by all means shows a flat amp.

Nothing suggest otherwise except of a bad sample,some strange heavy interaction with the speakers or who knows what else.

For reference that's the speaker:


View attachment 360723

Not the easiest out there but far from hard,the amp should drive it with ease.

I see, thank you very much. So, if i understand your words, even with audibly transparent gears (wiim+pa5, for instance), we always have to watch out for sinergy of the components, is that right?

 

[Sokel]

I see, thank you very much. So, if i understand your words, even with audibly transparent gears (wiim+pa5, for instance), we always have to watch out for sinergy of the components, is that right?

Synergy may not be the right terms,just sanity.
Calculate your power needs,a decent gain-structure,some fail-safe scheme for volume control and gear up to the task.

Also a way to measure,a mic with REW can expose many faults,both in room and proper operation as high distortion/noise/interferences can be evident.
But even an iphone and tools like Deltawave can be of service as you saw above.

Luckily,ASR has people who can assist (I don't mean me,I know less than the average person here) so asking is the best way to do it!

 

[Julf]

I see, thank you very much. So, if i understand your words, even with audibly transparent gears (wiim+pa5, for instance), we always have to watch out for sinergy of the components, is that right?

"Synergy" is another meaningless audiophile term. You just need to check that your speaker doesn't have some rare special needs, and then think about how much power and volume you need.

 

[afiqzali]

Hi all. I'm new to this forum. Bought my PA5 II Plus recommended from this review. loving it! its connected to my E50 DAC on balanced input.
Just want to ask, is it normal that it runs hot even on idle?

 

[Joaquinín]

"Synergy" is another meaningless audiophile term. You just need to check that your speaker doesn't have some rare special needs, and then think about how much power and volume you need.

Well, not only an audiophile term. If you have a legacy high impedance source, the PA5II rca 2K ohms input impedance is not going to be "synergistic" at all...

 

[Guddu]

"Synergy" is another meaningless audiophile term. You just need to check that your speaker doesn't have some rare special needs, and then think about how much power and volume you need.

How about defining "Synergy" as ability of the product to work/response with another product like ability of the amplifier to respond to lower impedance load and power availability under different load for different freq.?
Just saying ... for consideration.

 

[elmoe420]

Hi all. I'm new to this forum. Bought my PA5 II Plus recommended from this review. loving it! its connected to my E50 DAC on balanced input.
Just want to ask, is it normal that it runs hot even on idle?

Ours also runs hot even when idle. It's my wife's PC setup amp and she regularly forgets to turn it off at night. Always warm in the morning.

 

[Guddu]

Hi all. I'm new to this forum. Bought my PA5 II Plus recommended from this review. loving it! its connected to my E50 DAC on balanced input.
Just want to ask, is it normal that it runs hot even on idle?

Amplifier is using some power at Idle, probably below 10W, and so I would say its normal to feel the chassis slightly warm but "running hot" is kind of different.

 

[Julf]

How about defining "Synergy" as ability of the product to work/response with another product like ability of the amplifier to respond to lower impedance load and power availability under different load for different freq.?
Just saying ... for consideration.

In that case, how about defining "synergy" as "working to normal modern standards"?

 

[Julf]

Well, not only an audiophile term. If you have a legacy high impedance source, the PA5II rca 2K ohms input impedance is not going to be "synergistic" at all...

That is not how audiophools use the term.

 

[Guddu]

In that case, how about defining "synergy" as "working to normal modern standards"?

Okay... agreed.

 

[pseudoid]

"Synergy" is another meaningless audiophile term.

We learned what "synergy" (aka 'mutualism') was from JacquesCousteau.
Thus, I must ask; which is the shark and which one is the remora?

 

[Julf]

We learned what "synergy" (aka 'mutualism') was from JacquesCousteau.
Thus, I must ask; which is the shark and which one is the remora?

The audiophile marketing / promotion / media people are the sharks. The marks might not be remoras, but they might have remorse.