Topping PA7 Plus Amplifier Review

[robbiekhan]

I hear no distortion at any volume driving a pair of Triangle Comete 40th Anniversary, the source is a Luxsin X9 using XLR out and it's also the pre-amp, so PA7 is in bypass mode for reference. So yeah I'd say it's inaudible.

 

[Ahmonge]

@davmol
At 70-80 dB below the music, I don't think you'll hear 10-15 kHz treble distortion, but as always, trying before buying or a good returning period is the best policy.

 

[pma]

At 70-80 dB below the music,

Nothing can be heard if it is 70-80 dB below music level. Absolutely nothing. Even if it is another attenuated song. Such test files can be googled, try Bill Waslo.

 

[staticV3]

i.e. would the distortion shown on the PA7 Plus and V3 Monos at higher frequencies make an audible difference at higher volumes, vs the B200

See here:

G

'Is SINAD around 5-15 KHz relevant?'

Jul 19, 2024

I’m trying to build some active 3-way bookshelves. At this point, I need to decide for amp selection for my high frequency >2.5 KHz. I love Hypex products and will be powering the low end and midrange with hypex modules.

I’m a bit hesitant about the tweeter amplification. Most newer class D amps from Hypex and Purifi are great with power and low distortion, until they get to >10 KHz, where they suck. There are a few clas A/B amps out there that have better SINAD than the new class D amps above 10KHz. Would like some insight, am I overthinking it? Is it possible that some of the high...

• gags11
• Replies: 39
• Forum: Audio Power Product Reviews and Discussion

 

[EJ3]

I can pick one of these up for £250 ish and was considering it to replace my Fosi V3 Monos, purely for aesthetics

A rarity: putting out in the wild, that once the desired SINAD (and other specs) have been met, then aesthetics does come into play.
BRAVO!!!

 

[Boredcarrot]

I haven't read back through the entire thread, so sorry if this is a repeated topic - but did anyone else's PA7 plus run hot? Mine used to run so hot that I could imagine cooking an egg on it! It actually freaked me out to the point of getting rid it. I worried that, a). running so hot might effect its longevity and b). I live in a hot climate and actually worried the temp would raise the ambient temperature in my smallish room (seemed like a logical concern at the time but seems a bit OTT in hindsight). I was pretty disappointed to tell the truth, as it wasn't particularly cheap in Australia.

 

[Roland68]

I haven't read back through the entire thread, so sorry if this is a repeated topic - but did anyone else's PA7 plus run hot? Mine used to run so hot that I could imagine cooking an egg on it! It actually freaked me out to the point of getting rid it. I worried that, a). running so hot might effect its longevity and b). I live in a hot climate and actually worried the temp would raise the ambient temperature in my smallish room (seemed like a logical concern at the time but seems a bit OTT in hindsight). I was pretty disappointed to tell the truth, as it wasn't particularly cheap in Australia.

Without a measured temperature, the term "hot" is useless.
What was the ambient temperature in the room?
Was the PA7 standing freely and well-ventilated, or was something stacked on top of it?
How long could you put your hand on the case before it really hurt?

 

[Boredcarrot]

Without a measured temperature, the term "hot" is useless.
What was the ambient temperature in the room?
Was the PA7 standing freely and well-ventilated, or was something stacked on top of it?
How long could you put your hand on the case before it really hurt?

So you need a meaurement to tell you something is hot? What temperature would that be then? Sorry, I don't know how else I should describe something emitting heat.
It didn't matter what ambient temperature the room was, the unit was hot to the touch regardless.
Yes, well ventilated room and standing alone and away from any other components.
The egg comment was an exaggeration, but I would not 'comfortably' be able to hold it for more than a couple of seconds.

EDIT: for a little more (probably useless) context, I have a Topping PA5 II plus - gets warm to the touch, but not a concerning amount, I also have a Nord VL NC252MP power amp that barely gets warm to the touch. The PA7 plus used to get considerably 'warmer' (is that better)?

 

[Roland68]

So you need a meaurement to tell you something is hot? What temperature would that be then? Sorry, I don't know how else I should describe something emitting heat.
It didn't matter what ambient temperature the room was, the unit was hot to the touch regardless.
Yes, well ventilated room and standing alone and away from any other components.
The egg comment was an exaggeration, but I would not 'comfortably' be able to hold it for more than a couple of seconds.

EDIT: for a little more (probably useless) context, I have a Topping PA5 II plus - gets warm to the touch, but not a concerning amount, I also have a Nord VL NC252MP power amp that barely gets warm to the touch. The PA7 plus used to get considerably 'warmer' (is that better)?

Humans are completely unsuitable as thermometers. For one person, 32°C is hot, for another, 40°C. The difference between the perceived temperature of two people can easily be 10-15°C, sometimes even more. Different surface textures, coatings, and materials alone can cause perceived differences of 40°C or more.

If you can place your hand on it for a few seconds, it should be 40-45°C, probably less, which can be completely normal depending on the ambient temperature. At an ambient temperature of 28-35°C, this would actually be an extremely good reading.
And the ambient temperature is extremely important, as it directly influences the device temperature.

It's also important to remember that conventional amplifiers for the past 50 years have operated at temperatures above 45°C, often even above 50°C inside and on the heatsinks, often for 30 years at a room temperature of around 20°C. If this wasn't a problem before, why should it suddenly be one now?

 

[EJ3]

I was born in Salzburg but it gets too cold for me there.

Maybe it's the 95%-100% humidity outside (I keep my home between 35-50%), but if my home is over 26 C, I'm running the AC.
My house is fully in the shade and the outdoor temp in the shade (all 68 years of my life) from March to October is usually between 32 C (in the spring & the fall) & 37+ in the summer (with probably 13-14 days that are at 41 C). This is from meteorological boxes on my shaded property.
In the winter, there may be a 2 or 3 day light freeze (the ground makes a light crunching noise when to step on it but only the very surface is frozen) & about every 7 years or so, we get a dusting of snow (3 cm). It's generally between 4 C & 13 C in the winter.
About 5 year's ago (a few months before I returned after living +- 15 degrees N & S of the equator [in the Indian Ocean & Western Pacific] for 17 years), we got about 21 cm of snow. I understand that everything came to a stop for three days.
There is nothing in my home that runs as warm as 40 C (probably because of my normal 24-26 C ambient indoor temp).
Most people actually keep their indoor temperature lower than that because they do not run dehumidifiers like I do.

I'm guessing that the humidity has little effect on inanimate objects until they are actually wet from dripping condensation or something like that.
I would appreciate it if someone would let me know whether I am right or wrong about that.

 

[mike70]

I was born in Salzburg but it gets too cold for me there.

Maybe it's the 95%-100% humidity outside (I keep my home between 35-50%), but if my home is over 26 C, I'm running the AC.
My house is fully in the shade and the outdoor temp in the shade (all 68 years of my life) from March to October is usually between 32 C (in the spring & the fall) & 37+ in the summer (with probably 13-14 days that are at 41 C). This is from meteorological boxes on my shaded property.
In the winter, there may be a 2 or 3 day light freeze (the ground makes a light crunching noise when to step on it but only the very surface is frozen) & about every 7 years or so, we get a dusting of snow (3 cm). It's generally between 4 C & 13 C in the winter.
About 5 year's ago (a few months before I returned after living +- 15 degrees N & S of the equator [in the Indian Ocean & Western Pacific] for 17 years), we got about 21 cm of snow. I understand that everything came to a stop for three days.
There is nothing in my home that runs as warm as 40 C (probably because of my normal 24-26 C ambient indoor temp).
Most people actually keep their indoor temperature lower than that because they do not run dehumidifiers like I do.

I'm guessing that the humidity has little effect on inanimate objects until they are actually wet from dripping condensation or something like that.
I would appreciate it if someone would let me know whether I am right or wrong about that.

That's why a thermometer will be a precise number and not something like 500 words and surely many people still doesn't understand the temperature of the Amp.

Asking for a simple and basic measure can be the difference trying to help in an objective forum, and not to bother anyone.

 

[EJ3]

That's why a thermometer will be a precise number and not something like 500 words and surely many people still doesn't understand the temperature of the Amp.

Asking for a simple and basic measure can be the difference trying to help in an objective forum, and not to bother anyone.

If someone says that something is hot, then I presume that it is hotter than their other stuff.
& I would say: can you or can you not keep you hand on it.
If you can't for more than say 10 seconds, then measurement and an investigation as to what should be it's normal operating temp is in order.
But if you can keep your hand on it, then it's most likely not too hot.
Simple. and few words required. They were only required for people that don't WANT to be simple.
Most folks that I know don't have proper measurement gear in their home (an infrared temp gun as opposed to a candy thermometer).
The hand test MAY keep people out of the store (internet, or whatever).
On the other hand, if you have the proper measurement tools, I would still do the hand test, just to see if I needed to do more.
See, YOU caused more words to be needed.
For something so simple.
But you do you & I'll do me, thank you very much.

 

[mike70]

If someone says that something is hot, then I presume that it is hotter than their other stuff.
& I would say: can you or can you not keep you hand on it.
If you can't for more than say 10 seconds, then measurement and an investigation as to what should be it's normal operating temp is in order.
But if you can keep your hand on it, then it's most likely not to hot.
Simple.

I'm still thinking that a number is better
Hand / body temperature changes what you said, as others observed before.

We can't discuss the value of using a thermometer to get the temperature.

 

[EJ3]

I'm still thinking that a number is better
Hand / body temperature changes what you said, as others observed before.

We can't discuss the value of using a thermometer to get the temperature.

Of course, a number is better. But, if I (and others) can hold their hand on it...without their hand turning red before they pulled it away...my opinion would be...that it is not too hot.
Again, that is an opinion.
But if it is burning hot, then (in my opinion) measurement is definitely in order.

 

[tonyrob]

PA7, room is 75 degree, the top of the unit is 90~100. hope this helps.

 

[Roland68]

The biggest problem is the lack of knowledge about temperature in amplifiers.
We've had many users here in the forum write that their amplifier was much too hot and they feared a defect. Upon inquiry, it almost always turned out that they could leave their hand on it for more than 10 seconds, and subsequent measurements usually showed temperatures around 32-35°C.
That's why I always call it "heat hysteria."

This ignorance also includes the somewhat forgotten knowledge about the stable, temperature-dependent operating point of components. As a developer friend once said, don't trust any amplifier below 40°C.

But most people are concerned about longevity.
Let's take one of the most well-known and hot-running Class A amplifiers as an example, the Musical Fidelity A1 (the old one from the last millennium).
Operating temperature is around 60°C, sometimes higher in the summer.
As a rule of thumb, the lifespan of electrolytic capacitors halves every 6°C. In the Musical Fidelity A1, the capacitors need to be replaced approximately every 6-7 years when operated 24/7.
- At 54°C, that would be 12-14 years
- At 48°C, that would be 24-28 years
- At 42°C, that would be 48-56 years
And that brings us to the point where aging has a greater impact than temperature.
This also corresponds to the experience of conventional amplifiers over the past 50 years, which often ran for 30 years or more at temperatures above 45°C.

In addition, with Class D amplifiers, frequency has a greater influence on service life than temperature, at least below 50°C.
This should eliminate any concerns about excessively high temperatures in 99% of cases.

 

[robbiekhan]

Mine has been sat left on 24/7 most days on my desktop in a room that's often hovering around 25 degrees C. the top of the PA7 (non plus) is often 45-47 degrees. Absolutely zero problems as of yet since buying it in June.

On an unrelated note, I paid £500 for it back then, the Plus version was more expensive. Looking today on Amazon the PA7 is £350 whilst the Plus version (no difference other than the higher rated power supply...) is £600. Wtf is up with this pricing lol and why has the non plus dropped so much in price does anyone know? I'm kind of bummed out as I could have saved £150 if I waited a bit!

 

[Boredcarrot]

Humans are completely unsuitable as thermometers. For one person, 32°C is hot, for another, 40°C. The difference between the perceived temperature of two people can easily be 10-15°C, sometimes even more. Different surface textures, coatings, and materials alone can cause perceived differences of 40°C or more.

If you can place your hand on it for a few seconds, it should be 40-45°C, probably less, which can be completely normal depending on the ambient temperature. At an ambient temperature of 28-35°C, this would actually be an extremely good reading.
And the ambient temperature is extremely important, as it directly influences the device temperature.

It's also important to remember that conventional amplifiers for the past 50 years have operated at temperatures above 45°C, often even above 50°C inside and on the heatsinks, often for 30 years at a room temperature of around 20°C. If this wasn't a problem before, why should it suddenly be one now?

Thank you for the reply. Yes, I just wasn't sure if this was normal, but actually I also just realized today that my little PA5 II plus gets quite warm, just not as warm as the PA7 plus, so I concede that is most probaby 'normal'. I still so wonder about longevity though, but I admit to not know enough about electronics to know how reasonable that fear even is.

 

[Boredcarrot]

Thanks for the feedback everyone, sorry no time to address each one individually. To cap it off, it seems quite normal, from what I can gather here. Thanks again.

 

[Deleted member 88178]

Not even.

The PA7 Plus can play 10*log10(245/200)=0.88dB louder at 4Ω and 10*log10(135/125)=0.33dB louder at 8Ω.

View attachment 454973

This is really interesting!
So in terms of value the PA7 is clearly a better option than the PA7+?