Topping PA5 Review (Amplifier)

[D700]

Yes, for sure and also add a backlit illumination dimmer control. To get really funky use RGB lighting control so the user can set it and perhaps even have it tied into the motherboard lighting interface. But, seriously it's a great idea with the meters. @JohnYang1997

In all seriousness, as I chase the long tail of the curve on performance… aesthetics takes on more importance to me and I’m willing to pay more for stuff that looks great too

 

[Doodski]

In all seriousness, as I chase the long tail of the curve on performance… aesthetics takes on more importance to me and I’m willing to pay more for stuff that looks great too

In this case, it has huge personal value for peeps all across earth. Those meters are a sought after commodity.

 

[DanielT]

Put the crest factor in the amp headroom box and you're more or less good to go. Increase it further if you want headroom above the crest.

Interesting thoughts, I created a new thread:

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

 

[restorer-john]

I was too fast.

Yes Pavel, your slew rate can cause instability if you're not careful. But we can always get a rise out of you one way or another

Anyway, it's Christmas eve here, and I've been told to put down the soldering iron, stop looking at schematics and have a nice glass of red wine.

Merry Christmas to you all!

 

[Moosi]

This is a hype! This is madness!

I don't need it. I don't want it. Yet I will buy it next year, for I really want to know what it can do. This is the definition of a hype. Buying something you don't actually need just to satisfy the need to find out if it can live up to it.

 

[BoredErica]

This is a hype! This is madness!

I don't need it. I don't want it. Yet I will buy it next year, for I really want to know what it can do. This is the definition of a hype. Buying something you don't actually need just to satisfy the need to find out if it can live up to it.

In that case I'd wait for pa7.

 

[Toku]

If you have any doubts, it's best to check for yourself. Perhaps the purchase will change the awareness of PA5.

 

[antcollinet]

Yes Pavel, your slew rate can cause instability if you're not careful. But we can always get a rise out of you one way or another

Anyway, it's Christmas eve here, and I've been told to put down the soldering iron, stop looking at schematics and have a nice glass of red wine.

Merry Christmas to you all!

Ah - Australia. I was wondering where in the world the sun was low enough over the yard arm for red wine. It's still early in the am here.

Have a great Christmas.

 

[Redheart]

What output mode are you using on the E50 ?

View attachment 174304

Preamp mode

 

[Redheart]

If my PA5 is not enough power for me, and A07 is just OK, i guess i have to go purify then!
I would have loved to be set and done with the cheaper PA5 though.
Merry Christmas all!
Gonna test with a peamp and PA5 later after all the festivities

 

[misterdog]

The lower gain of PA5 (19.5dB) is the result of the SINAD wars here. You then get the magic 105 dB. If the gain was the usual 26 dB, then SINAD at 5W/4ohm would fall to 99.5dB and then there are competitors. I hope at least some readers are able to realize this.

I hope that some readers are able to realize that if I set my AHB2 to Low gain Input (9.2dB) and my M400 DAC to output maximum voltage on XLR 5.2V. I get less distortion .
I call that a war for better audio.

Of course some might argue that the 'usual' 'standards' are 26dB and 4V. and that I should thus ignore any potential 'gains' from deviating from these standards.

Where is it that these 'standards' are written, is it on a stone tablet somewhere ?

 

[Paco De Lucia]

I hope that some readers are able to realize that if I set my AHB2 to Low gain Input (9.2dB) and my M400 DAC to output maximum voltage on XLR 5.2V. I get less distortion .
I call that a war for better audio.

Of course some might argue that the 'usual' 'standards' are 26dB and 4V. and that I should thus ignore any potential 'gains' from deviating from these standards.

Where is it that these 'standards' are written, is it on a stone tablet somewhere ?

The "standards" are to enable a vaguely predictable signal chain and gain structure in not only domestic products but mainly for professional use in studios and broadcast settings

 

[dominikz]

The lower gain of PA5 (19.5dB) is the result of the SINAD wars here. You then get the magic 105 dB. If the gain was the usual 26 dB, then SINAD at 5W/4ohm would fall to 99.5dB and then there are competitors. I hope at least some readers are able to realize this.

Even with the ~19dB gain the amp gets to clipping with only ~2,5Vrms input (low for balanced input). If we wanted to make use of the full dynamic range of typical 4Vrms input (for optimal gain-staging with typical balanced DACs) we could argue that the gain should actually be even lower, around ~15dB, if keeping the output power the same.
On the other hand, an amplifier that can take ~4Vrms input with 26dB gain should be able to develop ~1,5kW into 4Ohm before clipping to make use of the full input dynamic range.
Am I missing something? If not, could someone please explain why is the "low" gain an issue here at all?

Also, shouldn't it be welcome that some manufacturer is taking a different approach (e.g. optimize for THD+N instead of power)? It gives us all more options so people can choose what fits their needs better.

Though I'd personally agree that power is typically the most important metric for a power amp, as long as distortion and noise aren't truly terrible.

 

[sarumbear]

True - but to increase the gain you also need to increase the power. You can't have more power without more gain, and you need an amp that can drive the power if you apply more gain. Applying more gain to an already maxed out amp will just drive it into clipping.

Put it another way - xdb more gain will require xdb more power from the amp.

I disagree. You can have more gain and the same power. They are not necessarily linked.

 

[dominikz]

I disagree. You can have more gain and the same power. They are not necessarily linked.

Sure - but the amp will clip at lower input voltage in that case.
Which can mean that some SNR/DR is sacrificed (depending on specific setup and the rest of the chain, of course).

 

[Lambda]

You can have more gain and the same power.

sure but it would be useless because it would cause only more clipping.

The Amp designed to make full power at around 2,5Vrms. Almost any DAC can deliver even more then this so the amp has more then enough gain for its power.
If you want more gain without clipping you need more power.

If your source can't deliver ~2,5Vrms your not using the right source for this amp.

 

[antcollinet]

I disagree. You can have more gain and the same power. They are not necessarily linked.

Isn't gain simply the ratio of input to output voltage? If gain goes up, output voltage goes up (if the amp is not clipping) and so power goes up in proportion to the square of the voltage, given the same speakers, and the same music.

What am I missing?

 

[pma]

Many recordings, especially of classical music, do not reach 0dBFS. Many have very low average level and you need to turn volume knob right much more than with popular music with DR5. You need gain, then. If you only listen to popular music with flat dynamics and tons of dynamics compression, then low gain is fine.

 

[Frank Sol]

Merry Christmas to you all!

Back at everyone

 

[dominikz]

Many recordings, especially of classical music, do not reach 0dBFS. Many have very low average level and you need to turn volume knob right much more than with popular music with DR5. You need gain, then. If you only listen to popular music with flat dynamics and tons of dynamics compression, then low gain is fine.

Good point, indeed.

However even with high-DR recordings, a low-power amp with high-gain will be pushed into clipping with the peaks. Average level will be good, but the peaks (which should be reaching close to 0dBFS) will then distort to some degree. So some of the DR would be lost in practice (almost like dynamically limiting the recording). This may or may not be an issue from audibility perspective, depending on clipping severity - of course.

And in the end I think the point people are arguing is just that, if one finds practical listening levels insufficient with a specific amp, a higher-powered amp would be a better solution than just having higher gain but the same power capability. And if levels are acceptable, low-gain would not be an issue at all.