Topping PA5 Review (Amplifier)

[F1308]

Do they really have to be TRS...?

Cheeeses....
I was about to order a couple of XLR/TRS converters, but after that I am going XLR female-TRS male cable.
Thank you for letting us know.

 

[SDC]

Great amp, terrible manual. If anybody in Topping watching this thread, go and read your manual's precaution section you guys wrote PA3, this is PA5

 

[KSTR]

As for test signals, my findings:

• Best signal to assess technical perfomance is 7kHz+13kHz 1:1 twin tone (explanation here).
• Best signal wrt what's going on with music-like signals is a sparse (no more than ~7 components) pink spectrum multitone. It has the right weighting of the components and allows to see any noise-floor modulation because the bottom line is not flooded by IMD components.

 

[KSTR]

Hey, is it better to max the volume of the amp (PA5) or max the volume of the DAC (EX5) ?

Max the volume on the DAC. This gives the best signal to noise/hum/buzz ratio, notably when you run unbalanced interconnects.

 

[F1308]

Hey, is it better to max the volume of the amp (PA5) or max the volume of the DAC (EX5) ?

I was always told long ago the original source should be at its maximum.

And yesterday we were told why....

Thank you, mdsimon2.

Topping PA5 Review (Amplifier)

@amirm did you move your hosting service to Facebook? Edit: Because this thread reminds me of why I left Facebook:)

www.audiosciencereview.com

Lovely, isn't it ?

As you see, the noise from the signal is increased by the gain you are applying at the amp, so the lower the gain, the better....if I am understanding well, that's it.

DACnoise x 10^(AMPgain/20) = DACnoise at amplifier output=DACnao

Then (DACnao^2+AMPnoise^2)^0.5=Total noise

And if the total noise is in the mid-100 uV, there is no hissing.

Yupiiii.

 

[F1308]

Great amp, terrible manual. If anybody in Topping watching this thread, go and read your manual's precaution section you guys wrote PA3, this is PA5

If they are telling not to have a shower with it, it is all the very same...

Indoor use only...?

Use Topping adaptor only ?

To cut power turn the unit first off, then pull the cable from mains...?

Ensure the unit is OFF before connecting/disconnecting any cable...?

 

[mdsimon2]

I was always told long ago the original source shoul be at its maximum.

And yesterday we were told why....

Thank you, mdsimon2.

Topping PA5 Review (Amplifier)

@amirm did you move your hosting service to Facebook? Edit: Because this thread reminds me of why I left Facebook:)

www.audiosciencereview.com

Lovely, isn't it ?

As you see, the noise from the signal is increased by the gain you are applying at the amp, so the lower the gain, the better....if I am understanding well, that's it.

DACnoise x 10^(AMPgain/20) = DACnoise at amplifier output=DACnao

Then (DACnao^2+AMPnoise^2)=Total noise

And if the total noise is in the mid-100 uV, there is no hissing.

Yupiiii.

Some caution on that mid-100 uV number, I've found that it works for me given an unpadded relatively sensitive tweeter (SEAS 27TBFCG) and my listening environment. It is possible that others are more sensitive to noise and/or have more sensitive speakers so they may have lower noise thresholds.

Nevertheless pairing the PA5 with any reasonably low noise DAC should be one of the lowest noise options you can come up with due to low amplifier gain and low residual noise of the amp itself.

Michael

 

[F1308]

Some caution on that mid-100 uV number, I've found that it works for me given an unpadded relatively sensitive tweeter (SEAS 27TBFCG) and my listening environment. It is possible that others are more sensitive to noise and/or have more sensitive speakers so they may have lower noise thresholds.

Nevertheless pairing the PA5 with any reasonably low noise DAC should be one of the lowest noise options you can come up with due to low amplifier gain and low residual noise of the amp itself.

Michael

Thank you.
We do understand any findings are based on equipment and tools that when changed might show or bring different results.
Love people with good wil...

 

[BoredErica]

Some caution on that mid-100 uV number, I've found that it works for me given an unpadded relatively sensitive tweeter (SEAS 27TBFCG) and my listening environment. It is possible that others are more sensitive to noise and/or have more sensitive speakers so they may have lower noise thresholds.

Nevertheless pairing the PA5 with any reasonably low noise DAC should be one of the lowest noise options you can come up with due to low amplifier gain and low residual noise of the amp itself.

Michael

You reckon Motu Utralite mk 5 + PA5 will have practically inaudible noise with LS50 metas even in very nearfield use? The sensitivity reads 85db, I think the tweeter is at that too with the resister in the speaker? I calculated this... Without many alternatives to the Motu, all I can do is get as low noise/gain as I can on the amp and PA5 does have lower gain than Buckeye.

Spoiler

Look at that pa5 go. ahb2 is still a good chunk better but this is already beating so many others.

 

[SDC]

If they are telling not to have a shower with it, it is all the very same...

Indoor use only...?

Use Topping adaptor only ?

To cut power turn the unit first off, then pull the cable from mains...?

Ensure the unit is OFF before connecting/disconnecting any cable...?

That is no excuse for wrong manual. Typo or copy paste whatever they did.

If it is so obvious just skip the whole precaution why waste ink

 

[F1308]

That is no excuse for wrong manual. Typo or copy paste whatever they did.

If it is so obvious just skip the whole precaution why waste ink

I misunderstood you: thought you were talking about unrelated precautions, not just the typo...

 

[mdsimon2]

You reckon Motu Utralite mk 5 + PA5 will have practically inaudible noise with LS50 metas even in very nearfield use? The sensitivity reads 85db, I think the tweeter is at that too with the resister in the speaker? I calculated this... Without many alternatives to the Motu, all I can do is get as low noise/gain as I can on the amp and PA5 does have lower gain than Buckeye.

Spoiler

View attachment 170826

Look at that pa5 go. ahb2 is still a good chunk better but this is already beating so many others.

I use an Ultralite Mk5 with an Audiophonics NC252MP (~26 dB gain) with the above mentioned SEAS tweeter (91.5 dB sensitivity at 2.83 V) in a nearfield setup with absolutely no trace of hiss. You should be fine as you have even less gain on the PA5 and your speakers are less sensitive.

Michael

 

[SDC]

I misunderstood you: thought you were talking about unrelated precautions, not just the typo...

It's ok, I should have wrote more clearly.

Photo for what I mean.

It is just a typo but still, disappointing.

 

[ModDIY]

View attachment 170835

It's ok, I should have wrote more clearly.

Photo for what I mean.

It is just a typo but still, disappointing.

It's not a big mistake, of course it looks looks like a copy and paste.

What often disappoints me are the small, barely readable manuals and also the lack of information. I don't have this manual in hand, I mean in general, Topping, SMSL, Sabaj ... etc.

 

[F1308]

View attachment 170835

It's ok, I should have wrote more clearly.

Photo for what I mean.

It is just a typo but still, disappointing.

Yes, it is a little of a pitty, but since there are no non-existing buttons, knobs or any kind of dials involved, no issues for me...

 

[misterdog]

pairing the PA5 with any reasonably low noise DAC should be one of the lowest noise options you can come up with due to low amplifier gain and low residual noise of the amp itself.

Imagine how low the noise of a Benchmark AHB2 amp is then using only 9dB of gain.

 

[F1308]

Imagine how low the noise of a Benchmark AHB2 amp is then using only 9dB of gain.

I think there is a threshold, a minimum, and then nothing is added, no true need for it.
Happy if got the very best, but unnecessary from a given technical point.

I guess it was the lack of extremely low noise from DACs what made it necessary expensive, better amps...????

Topping D90SE noise < 1.1µVrms

With Topping PA5, [email protected] and noise < 16µVrms...

((1.1×10^(19.1/20))^2+16^2)^.5=18.82

And with AHB2 in stereo, [email protected] and [email protected]...

Benchmark AHB2 Power Amplifier

Benchmark's new AHB2 Power Amplifier - "The Quietest, Cleanest Audio Amplifier on the Planet"

benchmarkmedia.com

((1.1×10^(9.2/20))^2+7.1^2)^.5=7.77

 

[pma]

Amplifier output noise = input stage noise x gain, mostly. So the amplifiers with low gain have an advantage, however one needs to get the level somewhere, so it transfers the noise issue to another component. Talking previously about NC122 x PA5, NC122 has higher gain of some 6dB and yes about twice the output noise. Yes 6dB, 6dB equals 2x. No magic here.

 

[misterdog]

So the amplifiers with low gain have an advantage

Though there is only a hairs difference in SNR between AHB2 In low gain (9.2dB) and in high gain (23 dB). There is also medium gain setting of 17 dB.

 

[Lambda]

As you see, the noise from the signal is increased by the gain you are applying at the amp, so the lower the gain, the better....if I am understanding well, that's it.

Keep in mind you can’t change the Gain of the Amplifier.
With the volume control your only Attenuating the input signal to the amp.

If your Amplifier Clips at max volume it has to muss Gain for your source.
Everything being equal the same AMP with less gain would perform better.