Topping PA5 Review (Amplifier)

[Rottmannash]

Full power with what? Sine wave? Couple of minutes probably. Music? 24/7. Full power RMS is the most useless specification ever.

John Yang said, "In 100W both channel condition, the amplifier would shut down before the SMPS at around 1 minute mark. The SMPS is more than adequate for this amplifier." So I guess the answer is one minute with music.

 

[Rottmannash]

Making the assumption that Topping are consistent in using the same connectors in different products the TRS inputs regular 6.35 mm (1/4 inch) stereo female jacks

From the web page for the D10 Balanced DAC https://www.tpdz.net/productinfo/666141.html but please note that the list of "in the box" accessories for the E50 Multi-input DAC and PA5 Amplifier do not include the TRS / XLR adaptors - pity, really.

Lucky for me I have the D10B and the adaptors. Good excuse to buy this amp...

 

[howard416]

Do you know of any examples or tutorials? That would be a fun first project for me

https://sound-au.com/project09.htm if you want to just populate some PCBs.

Or, once you learn the concepts behind op-amp-based filters, you can just make your own from protoboard.

As for summing stereo into mono, you can figure that out easily with Google.

 

[Rottmannash]

Measurements alone ? What else affects sound quality ? Looks, size, price, brand name or subjective reviews ?

His sarcasm was dripping.

 

[PeteL]

. Full power RMS is the most useless specification ever.

This is called a power amplifier. What do you mean Full power “rms” is a useles spec? What else matter more and do you know what rms mean?

 

[PeteL]

John Yang said, "In 100W both channel condition, the amplifier would shut down before the SMPS at around 1 minute mark. The SMPS is more than adequate for this amplifier." So I guess the answer is one minute with music.

I think the point is that music or any content will never stay at full power for seconds, let alone a minute because at this point it’d be heavily distorted, only the strongests peaks should reach the full power demand. Only a test signal can continuously be demanding full power.

 

[aj625]

His sarcasm was dripping.

I thought you didn't read his original post.

 

[xrk971]

I have a question. There is speculation that the PA5 uses a Texas Instrument Class D amplifier chip. I see that other Chinese and non-Chinese Class D amplifiers use chips by Texas Instruments and by Infineon. I think that Bel Canto has primarily used ICEpower chips. The Class D amplifier chip is a technologically complex product like the DAC chip, and therefore they are made by big tech corporations and are made in high volumes. Question: do the Hypex and Purifi amplifier IC boards have a Class D amplifier chip?

IcePower amps that I have seen use multiple custom ASIC (application specific integrated circuit) that provides a smart Class D amp controller that drives discrete output MOSFETs plus the ASIC provides a hundred other bits of info (almost every possible operational parameter can be monitored) and control. It’s a unique system and not a “chip”’. It’s very complex and flexible but only made by them.

Here’s a closeup of a 1200AS2 amp. It looks more like a computer than an amp. The MOSFETs are all mounted on the bottom side.

There is nothing to DIY or modify here.

 

[Rottmannash]

I thought you didn't read his original post.

I did-sarcasm at its finest, if a bit reserved. He had me going for a minute as well.

 

[Rottmannash]

IcePower amps that I have seen use multiple custom ASIC (application specific integrated circuit) that provides a smart Class D amp controller that drives discrete output MOSFETs plus the ASIC provides a hundred other bits of info (almost every possible operational parameter can be monitored) and control. It’s a unique system and not a “chip”’. It’s very complex and flexible but only made by them.

I just read an article where a DIY'er desoldered the output transisters from a UCD module to replace them with better ones-at least that's the way I read his explanation.

 

[Moosi]

How can a "38V/4A=152W" PSU power a 2x125W amp? Even if it's custom made for music playing purpose, this seems a bit low. The PA3s has a "26V/5.75A=149W" PSU which is basically the same output in watts, but the PA3 is not nearly as powerful.

 

[Rottmannash]

How can a "38V/4A=152W" PSU power a 2x125W amp? Even if it's custom made for music playing purpose, this seems a bit low. The PA3s has a "26V/5.75A=149W" PSU which is basically the same output in watts, but the PA3 is not nearly as powerful.

This question has been asked several times-perhaps the answer to this question can be inserted in the 1st page or so of the review to prevent it from being answered over and over. I'd answer it but don't have the knowledge to understand the answer but those that do purport the power supply can provide in excess of the required voltage and current to power the amp to those levels. But I could be totally wrong

 

[xrk971]

Y'all are very helpful and I am thankful for that, but you and the others keep missing the point: multiple people would love (and would PAY) to have this feature in a ready-to-purchase product. There are plenty of DIY and paid hack-y (miniDSP, inline filters) solutions out there, yet it would be GREAT if there were a high resolution DAC with a digital crossover option so you could set a frequency to high pass your speakers and low pass your subwoofer. (There's some SMSL DACs with sub-out but doesn't appear to filter anything).

Apologies for the tangent that really doesn't have much to do with this amplifier so let me end by saying this amplifier looks fantastic, performs well above expectations, and is very reasonably priced. Well done to Topping!

I wasn’t talking about a power amp with built in DSP and sub output. I was talking about how to measure your own amp’s distortion and other parameters using a basic consumer USB sound interface and REW software.

I think miniDSP makes an amp plus DSP. So does Dayton, they have a new Class D amp with built in DSP that is easy to program/control. For example here.

 

[Walter]

I wasn’t talking about a power amp with built in DSP and sub output. I was talking about how to measure your own amp’s distortion and other parameters using a basic consumer USB sound interface and REW software.

I think miniDSP makes an amp plus DSP. So does Dayton, they have a new Class D amp with built in DSP that is easy to program/control. For example here.

Yes, but it has poor performance: https://www.audiosciencereview.com/...-audio-apa1200dsp-review-dsp-amplifier.28264/

 

[Bruce Morgen]

It’s a unique system and not a “chip”’.

The last two letters of "ASIC" stand for "Integrated Circuit" -- IOW, an ASIC is "a chip," just not an off-the-shelf "jellybean" part that you can simply order from Digi-Key or Arrow like TI's monolithic "chip amp" solutions or an Infineon Class D driver/controller for discrete MOSFETs.

 

[Wirrunna]

The User Manual (https://www.topping.audio/download) specifications state Standby Power Consumption <0.1w .
Does the PA5 drop in to standby mode after a certain amount of time with no signal ? If so, that would indicate power could simply be left on and the amp would fire up on receiving input signal. Can someone confirm or deny, please.

Edit : Thinking further, I suspect "Standby" is when the power brick is plugged in the mains but the power button on the amp is off.

 

[TimF]

IcePower amps that I have seen use multiple custom ASIC (application specific integrated circuit) that provides a smart Class D amp controller that drives discrete output MOSFETs plus the ASIC provides a hundred other bits of info (almost every possible operational parameter can be monitored) and control. It’s a unique system and not a “chip”’. It’s very complex and flexible but only made by them.

Here’s a closeup of a 1200AS2 amp. It looks more like a computer than an amp. The MOSFETs are all mounted on the bottom side.
View attachment 168944
There is nothing to DIY or modify here.

Is it fair to say that the ICEpower module was designed primarily for audio amplification and with a targeted frequency range? Is it likely that Texas Instrument Class D amp chips are designed for a broader range of amplification uses beyond audio?

 

[Bruce Morgen]

Is it likely that Texas Instrument Class D amp chips are designed for a broader range of amplification uses beyond audio?

No -- the TASxxxx and TPAxxxx devices are audio-specific.

 

[brandonhall]

https://sound-au.com/project09.htm if you want to just populate some PCBs.

Or, once you learn the concepts behind op-amp-based filters, you can just make your own from protoboard.

As for summing stereo into mono, you can figure that out easily with Google.

Thanks!

 

[Walter]

Who would have thought we'd get two reviews in 3 days where a $350 amp had over twice the SINAD of a $1500 DAC!?!