Topping PA7 Plus Amplifier Review

[AzReciOn]

I have a 7 year old Cambridge Audio CXA80 using with monitor audio silver 100. I'm thinking of getting a PA7 to replace the Cambridge, but is it really worth it?

I have already expressed this opinion, so it will be a repeat.

I believe that in your case (with the CXA80), the PA7 makes sense only as a second amplifier for low frequencies (with connection from the PRE-OUT of the main amplifier*), because it is here (up to 1.5-2 kHz) that it manifests itself best and surpasses the absolute majority of AB-amplifiers (of course, provided that your speakers supports bi-amping). This makes sense if your speakers have low impedance at low frequencies and you are having some trouble controlling the low frequencies with your current amplifier or you just don't have enough power. This will greatly relieve your CXA80, however, in the case of a complete replacement, you will most likely lose in the upper frequencies, since this amplifier (like the absolute majority of other D-class amplifiers) has a frequency dependence.
Whether this will save your amplifier from the shortcomings you described is unknown.
The transformer hum may have a dependence on the power source, including grounding. Heating the amplifier is in the order of things.

P.S. Personally, I am a little confused by the upside-down board in PA7 - I am not sure that this contributes to the proper heat removal from the components (and as we know, PA5 and PA7 are prone to heating).

*I am the owner of PA5 myself (I added a good cooling to it) - and I use it in the way described above, and in this it is really very good. Does it make sense to do such a bi-amping in the case of compact shelf speakers with an already powerful enough good amplifier (like yours) - most likely not.

 

[MAB]

I have already expressed this opinion, so it will be a repeat.

I believe that in your case (with the CXA80), the PA7 makes sense only as a second amplifier for low frequencies (with connection from the PRE-OUT of the main amplifier*), because it is here (up to 1.5-2 kHz) that it manifests itself best and surpasses the absolute majority of AB-amplifiers (of course, provided that your speakers supports bi-amping). This makes sense if your speakers have low impedance at low frequencies and you are having some trouble controlling the low frequencies with your current amplifier or you just don't have enough power. This will greatly relieve your CXA80, however, in the case of a complete replacement, you will most likely lose in the upper frequencies, since this amplifier (like the absolute majority of other D-class amplifiers) has a frequency dependence.
Whether this will save your amplifier from the shortcomings you described is unknown.
The transformer hum may have a dependence on the power source, including grounding.

P.S. Personally, I am a little confused by the upside-down board in PA7 - I am not sure that this contributes to the proper heat removal from the components (and as we know, PA5 and PA7 are prone to heating).

*I am the owner of PA5 myself (I added a good cooling to it) - and I use it in the way described above, and in this it is really very good. Does it make sense with small shelf speakers with a fairly powerful good main amplifier (like yours) - most likely not.

You mean passive bi-amp??? This is a way to spend money with no benefit in sound.
Especially since it won't fix the transformer buzz in the Cambridge, rather will end up with a larger and more complicated pile of gear and still have to listen to buzzing sounds.

Also, the PA5 has reliability issues because the components are encapsulated, not because of board orientation or excess heart. An ASR member has identified the issue and offers a fix. This practice of circuit encapsulation is one of Topping's silly problems and has resulted in unreliability, and caused people to take all sorts of performative measures in the belief they can somehow improve the stresses of the encapsulation.

I'm really not a fan of making things complicated, and adding another amp seems an odd way to not fix OP's issue, and make a complicated stack of amps that have no sound benefit and in fact add additional sources of unreliability. There are so many fantastic amps on the market that will properly drive just about any speaker. Like a 100 Watt per channel Yamaha with a built in DAC and tone controls input switching:

Yamaha A-S701 (Silver)

Stereo integrated amplifier with built-in DAC

www.crutchfield.com

 

[AzReciOn]

You mean passive bi-amp??? This is a way to spend money with no benefit in sound.
Especially since it won't fix the transformer buzz in the Cambridge, rather will end up with a larger and more complicated pile of gear and still have to listen to buzzing sounds.

Also, the PA5 has reliability issues because the components are encapsulated, not because of board orientation or excess heart. An ASR member has identified the issue and offers a fix. This practice of circuit encapsulation is one of Topping's silly problems and has resulted in unreliability, and caused people to take all sorts of performative measures in the belief they can somehow improve the stresses of the encapsulation.

I'm really not a fan of making things complicated, and adding another amp seems an odd way to not fix OP's issue, and make a complicated stack of amps that have no sound benefit and in fact add additional sources of unreliability. There are so many fantastic amps on the market that will properly drive just about any speaker. Like a 100 Watt per channel Yamaha with a built in DAC and tone controls input switching:

Yamaha A-S701 (Silver)

Stereo integrated amplifier with built-in DAC

www.crutchfield.com

It seems to me that I have already described the situation from different sides, without trying to prove any unambiguous position - re-read my message (keep in mind that English is not my native language - and there may be translation inaccuracies)...

As for the amplifier you gave as an example, I also have A-S500 and A-S301 - all of them noticeably lose to my PA5 at low and medium frequencies, as well as in channel separation. The DAC in the A-S701 is really not bad, but only as a temporary solution. And I don't understand why he is here when a person writes about the CXA80 - his device is a little higher level both as an amplifier and as a DAC.

 

[MAB]

It seems to me that I have already described the situation from different sides, without trying to prove any unambiguous position - re-read my message (keep in mind that English is not my native language - and there may be translation inaccuracies)...

As for the amplifier you gave as an example, I also have A-S500 and A-S301 - all of them noticeably lose to my PA5 at low and medium frequencies, as well as in channel separation. The DAC in the A-S701 is really not bad, but only as a temporary solution. And I don't understand why he is here when a person writes about the CXA80 - his device is a little higher level both as an amplifier and as a DAC.

I understand your English and appreciate!

Regarding amp sound, please read this:

Actual Double Blind Studies

I have always been curious about 'training' for these tests. I saw a visual test that used an aerial pic of a full Rose Bowl, and instantaneous ABX testing was used to compare two pics and seeing if people could notice the difference between them. The subjects couldn't do it. Then, the tester...

www.audiosciencereview.com

Note that the only tests where subjects were able to discern differences are ones where due to amps with impedance interacting with speaker's impedances causing Frequency Response changes., or with amps that were not operating properly.
Level matched, you will not be able to hear differences in these amps. They are just providing voltage gain. This has been known for decades, and people routinely fail to actually be able to hear the differences in controlled listening. The sham is that manufacturers have promoted the idea that we can hear these differences, and our mind is a willing participant in the hallucination.

Regarding hallucinations, ears fool us because of our predispositions.

Actual Double Blind Studies

I have always been curious about 'training' for these tests. I saw a visual test that used an aerial pic of a full Rose Bowl, and instantaneous ABX testing was used to compare two pics and seeing if people could notice the difference between them. The subjects couldn't do it. Then, the tester...

www.audiosciencereview.com

In summary, I don't agree. Nor does the body of science that has actually investigated amps.

 

[AzReciOn]

I understand your English and appreciate!

Regarding amp sound, please read this:

Actual Double Blind Studies

I have always been curious about 'training' for these tests. I saw a visual test that used an aerial pic of a full Rose Bowl, and instantaneous ABX testing was used to compare two pics and seeing if people could notice the difference between them. The subjects couldn't do it. Then, the tester...

www.audiosciencereview.com

Note that the only tests where subjects were able to discern differences are ones where due to amps with impedance interacting with speaker's impedances causing Frequency Response changes., or with amps that were not operating properly.
Level matched, you will not be able to hear differences in these amps. They are just providing voltage gain. This has been known for decades, and people routinely fail to actually be able to hear the differences in controlled listening. The sham is that manufacturers have promoted the idea that we can hear these differences, and our mind is a willing participant in the hallucination.

Regarding hallucinations, ears fool us because of our predispositions.

Actual Double Blind Studies

I have always been curious about 'training' for these tests. I saw a visual test that used an aerial pic of a full Rose Bowl, and instantaneous ABX testing was used to compare two pics and seeing if people could notice the difference between them. The subjects couldn't do it. Then, the tester...

www.audiosciencereview.com

In summary, I don't agree. Nor does the body of science that has actually investigated amps.

I'm not sure if I can distinguish between amplifiers unfamiliar to me, but I can distinguish my own amplifiers, especially the difference is great at low frequencies (I also have a simple D-class amplifier that can't be confused with anything by the noise level at high frequencies, but I don't use it now).

To be honest, I am absolutely not interested in going into this discussion here - I have no idea how a site with measurements can be interesting to those who have everything sounds the same and there is no difference (for me there is a difference).

 

[Namesbuck]

Thanks for getting back!! I'm happy with sounds that comes out of the amp. It drives the monitors really well and can get very loud. Few downside with this amp, it heats up, but I think that's normal with class a/b amps. Also the toroidal transformer has a hum/buzz when there is silence(a few others have said this about the cxa series) so maybe that's why I wanted to try the PA7 but it's true what you have said about wasting money when I have a functioning beast of an amp lol. I'll get more use out of it a couple of more years

If you are using for stereo audio listening or are interested in going to separates from your integrated setup, I would say it's a good upgrade. A large part of audio hardware is about looks and matching components. I upgraded from an a/b amp to this amp and it did remove some discernable distortion. Your milage may vary. Your amp is good enough but good enough is not what the hobby is about.

 

[MAB]

I'm not sure if I can distinguish between amplifiers unfamiliar to me, but I can distinguish my own amplifiers, especially the difference is great at low frequencies (I also have a simple D-class amplifier that can't be confused with anything by the noise level at high frequencies, but I don't use it now).

To be honest, I am absolutely not interested in going into this discussion here - I have no idea how a site with measurements can be interesting to those who have everything sounds the same and there is no difference (for me there is a difference).

For sure the person with the CXA80 with the transformer buzzing will not benefit from your suggestion.

Looks like you are missing the point of the site regarding the rest though...

 

[AzReciOn]

For sure the person with the CXA80 with the transformer buzzing will not benefit from your suggestion.

Looks like you are missing the point of the site regarding the rest though...

You seem to be missing out on the possibility of having a different opinion...
Let's stop this discussion off topic - I described my vision about PA7 from different angles (without asserting anything), and I'm sorry that it doesn't fit into your coordinate system.

 

[MAB]

You seem to be missing out on the possibility of having a different opinion... Let's stop this discussion off topic - I described my vision about PA7 from different angles, and I'm sorry that it doesn't fit into your coordinate system.

Uh.
I initially recommended against getting a second amp to the person who asked.
When they corrected me and pointed out that the amp they had has an audible buzzing transformer, I changed my mind and said maybe they should get the PA7 since they had a faulty amp. You chimed in and suggested they to passive bi-amp, perhaps you didn't read what their actual problem is.

 

[AzReciOn]

Uh.
I initially recommended against getting a second amp to the person who asked.
When they corrected me and pointed out that the amp they had has an audible buzzing transformer, I changed my mind and said maybe they should get the PA7 since they had a faulty amp. You chimed in and suggested they to passive bi-amp, perhaps you didn't read what their actual problem is.

You may not have read my answer ...
I expressed my opinion for what purposes I see the point in using PA7, finally summing up that I personally do not see the point in this case, suggesting to look for a problem in the AC power supply (but this is not the topic of this discussion).

I think this is not a topic at all for discussing other devices and their problems, except for PA7. Therefore, I propose to stay within the framework of the topic and stop the flood. I hope for understanding.

 

[MAB]

You may not have read my answer ...

I did.

 

[Freighter]

Does this amplifier have common protection mechanisms like overcurrent / short protection, over voltage protection and overheat protection? I can’t really find any information about it.

 

[LumenMedia]

Hi. Need your advice about correct pairing of this amp via XLR and my Antelope Audio Synergy Core 4. It has various gain setting for adjusting output gain, starting from +14 dbu and up to 20 dbu. Which one considered correct settings for this amp? Thanks

 

[Blink Too Fast]

It is rarely a good idea to biamp anything.

Bi-amping 101

This article provides a quick look at how bi-amplification works. The conventional scheme is to split the signal into two frequency bands before the power amplifiers that drive the speakers. The bass (LF) amp sees only LF signals and drives only the LF driver (woofer). The treble (HF) amp sees...

www.audiosciencereview.com

Thanks for the link. You and I may have read it differently.

My conclusion from it is that biamping before the crossovers is detrimental, and that biamping after the crossovers is an excellent thing to do to reduce intermodulation and amp power requirements, or to sum the power of existing amps.

 

[NTK]

Thanks for the link. You and I may have read it differently.

My conclusion from it is that biamping before the crossovers is detrimental, and that biamping after the crossovers is an excellent thing to do to reduce intermodulation and amp power requirements, or to sum the power of existing amps.

I was responding SiamXIII's post, and he asked whether it is a good idea to bi-amp the KEF R3.

Unless you are technically knowledgeable enough and want to play loudspeaker design engineer, "passive bi-amping" the R3 is largely a waste of money. If you want to properly actively bi-amp or tri-amp the R3 (i.e. cross-over upstream of the speaker amps), you'll need to reverse engineer the cross-over into a line level one, which is no easy task, especially if your goal is to do better than what the KEF engineers have done.

 

[vitalii427]

Ordered two at 11.11 sale

 

[Blink Too Fast]

I was responding SiamXIII's post, and he asked whether it is a good idea to bi-amp the KEF R3.

Unless you are technically knowledgeable enough and want to play loudspeaker design engineer, "passive bi-amping" the R3 is largely a waste of money. If you want to properly actively bi-amp or tri-amp the R3 (i.e. cross-over upstream of the speaker amps), you'll need to reverse engineer the cross-over into a line level one, which is no easy task, especially if your goal is to do better than what the KEF engineers have done.

That is typically what I (and many other people) do.
A MiniDSP 2x4, FLEX, DDRC, or similar, plus affordable amps that suddenly have a smaller job to do.
Calibrate it all with free REW software and a UMIK mic.
Bonus of simultaneous room correction

 

[NTK]

That is typically what I (and many other people) do.
A MiniDSP 2x4, FLEX, DDRC, or similar, plus affordable amps that suddenly have a smaller job to do.
Calibrate it all with free REW software and a UMIK mic.
Bonus of simultaneous room correction

Okay. I'll give you the benefit of the doubt that you know what you are doing. But I'll say I am doubtful.

Since this discussion is off topic for this official product review thread, this is my last post on this subject in this thread. If you wish to continue this discussion, please start a new thread.

 

[MAB]

That is typically what I (and many other people) do.
A MiniDSP 2x4, FLEX, DDRC, or similar, plus affordable amps that suddenly have a smaller job to do.
Calibrate it all with free REW software and a UMIK mic.
Bonus of simultaneous room correction

Hey, can you post some measurements of your active R3?
Also, R3 is a 3-way, don’t you need a Flex Eight or HTx?
How would you use a DDRC? That just has 2 channels of filters.

 

[Blink Too Fast]

Hey, can you post some measurements of your active R3?
Also, R3 is a 3-way, don’t you need a Flex Eight or HTx?
How would you use a DDRC? That just has 2 channels of filters.

Sure, I have a Flex Eight being used as 2x6, with the two spare channels correcting some vintage Sansui SF-2 omnis.
Amped with a mix of PA7 and Fosi V3.
Measurements below, though correcting a mix of Morrison Audio 29 and 42, not R3s.

The ability of the MiniDSP to correct many speakers and their rooms is amazing.
Red is corrected.
Blue, orange, green are before correction.

I think the HT & HTx are not yet released, but I may be wrong. I'm waiting for an HT to replace my AVR (with 3 Fosi V3 amps)