Topping PA5 Review (Amplifier)

[laudio]

This entire thread is pretty funny. Guy hooks up the PA5 and says it isn't as loud as his other amps. Because it isn't. But people like to browbeat somebody because they might not understand the lower gain aspect of it (it's not a typical power amp, let's face it). PA5 is a low gain power amplifier targetted at delivering excellent measurements, and arguing about power vs. gain isn't going to get anywhere, most people just want to hook something up and listen. And hear what sounds as loud than something else they have.

 

[0bs3rv3r]

It may not have the power of the PA5 and it’s only got a single input and 20watts into 4ohms
but the sound and build quality is superb for £129 including a high output low noise PSU.

Ah yes, Tripath. I think people may have forgotten that it actually sounded great. I still have a TA-2050 unit.

 

[MarkWinston]

Explain me why not. I understand the concept of gain and distortion, but, for me a basic "scientific experiment" consists and keep all variables except one immutable and compare the results, and then figure it out the reason of the results. In my case, my original impression (that was proven to be right) was that the PA5 was weaker (less loud, quieter, whatever wording you want) than the Aiyima 07. People called me crazy. Numbers proven that is the case.

Now I know, thanks to far more useful answers here, that the difference I heard was because of the gain. Nice, now I know. Isn't that the purpose of this forum? Telling a fact (I heard one amp louder than the other), use numbers to figure it out why and understand the reason behind it? Isn't that science?

I understand that volume knob position isn't a useful comparison for effective power vs distortion or other more advanced measurements. But it is definitely a useful tool to compare two different amp topology behaviors, isn't it?

How is the volume knob position a useful tool to compare amp topology behaviour??? Amp A : volume knob at 9 o'clock position, 105db. Amp B : volume knob at 2 o'clock position, 105 db. Both clips at anything higher than that. In your case, you would just need to turn up the volume on the PA5 to get the same exact volume as the A07. The A07 will not play louder than the PA5 without running in clipping levels. Volume knob position is and never will be an acceptable comparison tool.

 

[0bs3rv3r]

This entire thread is pretty funny. Guy hooks up the PA5 and says it isn't as loud as his other amps. Because it isn't. But people like to browbeat somebody because they might not understand the lower gain aspect of it (it's not a typical power amp, let's face it). PA5 is a low gain power amplifier targetted at delivering excellent measurements, and arguing about power vs. gain isn't going to get anywhere, most people just want to hook something up and listen. And hear what sounds as loud than something else they have.

If you don't clarify the terminology, all the rest of the discussion becomes meaningless.

 

[bsas]

If you don't clarify the terminology, all the rest of the discussion becomes meaningless.

OK, so, please “clarify” to me what is the “correct” terminology to describe why one amp is louder in MY situation than the other one?

I already stated multiple posts ago that I understand that when I wrote “underpowered” I understood that’s the wrong terminology. So, what is the correct one?

 

[bsas]

I have to say that the switch “IN1/IN2” on the PA5 is extremely handy to help compare other components, like different preamps or DACs

 

[0bs3rv3r]

OK, so, please “clarify” to me what is the “correct” terminology to describe why one amp is louder in MY situation than the other one?

I already stated multiple posts ago that I understand that when I wrote “underpowered” I understood that’s the wrong terminology. So, what is the correct one?

People have been trying to explain it to you for pages now...

 

[ogonex]

Muszę powiedzieć, że przełącznik „IN1/IN2” na PA5 jest niezwykle przydatny do porównania innych komponentów, takich jak różne przedwzmacniacze lub przetworniki cyfrowo-analogowe

Próbowaliście tu powiedzieć, że DAC dedykowany PA5 nie pozwala na osiągnięcie pełnej mocy, co okazało się bzdurą.
Ponieważ E50, gdy ma głośność wyjściową -6, daje pełną moc PA5.
To wszystko

 

[bsas]

You tried to say here that the DAC dedicated to the PA5 does not allow you to reach full power, which turned out to be nonsense.
Because E50 when have output volume -3 give the full power of PA5.
Thats all

Why? I don’t doubt it, I am just trying to understand.

The PA5 as we agreed (and it’s on is specs) have an input sensitivity of 2.6Vrms, but, I don’t know (and that is why I am here, to ask and learn) if this number is for the balanced total or just per signal.

What do I mean? Well, we all know that a balanced signal has the same signal twice with the polarity reversed. For example, if an SE signal is 2Vrms, the matching balanced signal will have 2Vrms for each “copy”, but, when you do the differential sum obviously the final signal doubles, so, 4Vrms.

So, when the PA5 specs stated it’s sensitive to 2.6Vrms I am not sure if this is the sum or per signal.

If it’s the sum, sure, I agree with you because the E50 DAC does output 4Vrms (combined, I measured) from the TRS balanced output.

But, if this 2.6Vrms is “per signal”, no, because the E50 outputs 2Vrms (I measured too). Right?

 

[bsas]

People have been trying to explain it to you for pages now...

OK, so, tell me the correct terminology.

Is it “low gain power amp”? Lower distortion topology? Preamp dependent? I don’t know.

I called it “underpowered”. You said it’s the wrong terminology. Fine, so, what is the correct one? I am honestly asking to learn and to avoid this “confusion” in the future…

 

[ogonex]

Why? I don’t doubt it, I am just trying to understand.

The PA5 as we agreed (and it’s on is specs) have an input sensitivity of 2.6Vrms, but, I don’t know (and that is why I am here, to ask and learn) if this number is for the balanced total or just per signal.

What do I mean? Well, we all know that a balanced signal has the same signal twice with the polarity reversed. For example, if an SE signal is 2Vrms, the matching balanced signal will have 2Vrms for each “copy”, but, when you do the differential sum obviously the final signal doubles, so, 4Vrms.

So, when the PA5 specs stated it’s sensitive to 2.6Vrms I am not sure if this is the sum or per signal.

If it’s the sum, sure, I agree with you because the E50 DAC does output 4Vrms (combined, I measured) from the TRS balanced output.

But, if this 2.6Vrms is “per signal”, no, because the E50 outputs 2Vrms (I measured too). Right?

You have a table here in post #2826? Can't you see that at 2.06V on XLR the PA5 reaches full power? What else are you not able to understand?

 

[nagster]

Why are you spending so many pages discussing?

When determining the output power performance of an amplifier, the volume knob position and gain are irrelevant.
There are no such provision or customs.
According to Amirm's measurement, A07 is 77W (4ohm / THD + N -75dB).
PA5 is 100W (4ohm / THD + N -75dB).

 

[bsas]

You have a table here in post #2826? Can't you see that at 2.06V on XLR the PA5 reaches full power? What else are you not able to understand?

Got it, understand that now and I agree I was wrong about my statement that the E50 cannot power the PA5. Clearly it can overpower it to clipping.

Thanks!

 

[bsas]

Why are you spending so many pages discussing?

When determining the output power performance of an amplifier, the volume knob position and gain are irrelevant.
There are no such provision or customs.
According to Amirm's measurement, A07 is 77W (4ohm / THD + N -75dB).
PA5 is 100W (4ohm / THD + N -75dB).
Is it necessary to explain which is higher output for 77W vs. 100W?
View attachment 176346View attachment 176347

I am not discussing, I am just trying to understand. Those graph comparisons made it more clear to my and I understand now, thanks!

 

[mocenigo]

This entire thread is pretty funny. Guy hooks up the PA5 and says it isn't as loud as his other amps. Because it isn't. But people like to browbeat somebody because they might not understand the lower gain aspect of it (it's not a typical power amp, let's face it).

I think this is just a power amp. What “typical” means is not clear. 26Db of gain is a consumer electronics “standard” and “typical” power amps have gains of 23Db, 15Db, 6Db (yes, some SE DHT low power amps to be used with very high efficiency horn loaded speakers), unity gain (like current followers), 26Db, 29db, 32db, you name it. On everything else you are absolutely right. People that complain that the PA5 sounds “weaker” just do not realise that different amps may have different gains. In this particular case I think it was just bad choice of terminology more than a criticism of the device.

 

[DanielT]

It is a good amplifier. It has the effect/power it has, it becomes what it becomes with level listening volume A and speakers B (sensitivity) in listening room C (size, listening distance) with music D (level dynamics). There is nothing strange about that.

How much power does an amplifier need with this type of range of dynamic music

Feel free to use this calculator. Add sensitivity to the speaker and then tell which effect you have chosen and why. Weigh in that you want some headroom. http://www.mh-audio.nl/Calculators/REAP.html You can select music from this list. Or something else, but in that case tell us how you...

audiosciencereview.com

 

[mocenigo]

My take is that this is not so much a quality problem (as in quality of assembly) but a design problem. Picture below is from post #1013.

The nut (with the serrated lock washer) holding the speaker binding post compresses against the rear chassis panel through a thick plastic piece (for electrical insulation).

Why the serrated lock washer in this case?

 

[mocenigo]

I can not hear nothing at 20 kHz now but it is a important paramenter to me, the phase curve. With Class A and A/B it is never a problem (< 6º at 20 kHz, usually).

So, why is it important?

 

[Solveit]

So, why is it important?

Beacuse people can measure weird stuff that nobody could hear.

 

[mocenigo]

Beacuse people can measure weird stuff that nobody could hear.

Well, ok, but if the two channels have the same phase shift, this should not be audible. So I do not understand why this is important to maty.