Aiyima A07 - measurements/performance analysis?

[BillG]

I'm just curious if anyone has measurements/a performance analysis of the following:

https://www.aiyima.com/products/amplifier-aiyima-a07-tpa3255-2-0-channel-300wx2-hifi

I'm quite tempted to purchase one as I've heard good things about the TPA325x series of amplifier chips, and I like inexpensive, clean and powerful amplification. By the way, I'm not looking for suggestions regarding other amps.

Thanks in advance

 

[Tim6622]

From Texas instrument's website. I have the 165w stereo version and the power supply needed to be ordered separately so consider that in cost. Imo I would not consider the t chip amps as a "clean" amplifiers judging by the thd measurements in the pdf. I would think more in the ballpark of ❄icepower❄ or hypex amps since they have lower thd.

 

[BillG]

From Texas instruments website. I have the 165w stereo version and the power supply needed to be ordered separately so consider that in cost. Imo I would not consider the t chip amps as a "clean"
Amp judging by its thd measurements in the pdf. I would think more in the ballpark of ❄icepower❄ or hypex amps since they have lower thd.

None of that is what I was inquiring about, and the advice is unsolicited and will be ignored.

 

[restorer-john]

None of that is what I was inquiring about, and the advice is unsolicited and will be ignored.

@Tim6622 linked the datasheet. You should read it perhaps, instead of dismissing what was an intelligent and useful post. If you just want people to agree with you, and chastise them for another view, this isn't the place.

The performance of the TPA-3255 is not good. It's rather noisy (160uV is ten times what a good amp can deliver), has high THD and the rated power output of the device in question cannot be achieved with the rated power supply range they suggest.

To get even close to the spec, you'd need a 51V 650W supply, which would need to deliver nearly 13A through a 2.5mm DC coaxial power plug- something that would just never happen.

 

[BillG]

Not today, John. I don't like you, I don't respect you, and I wouldn't listen to if you were the last person on Earth.

 

[mikeburns]

Seems like the measurement/performance analysis you're after was included in the attached pdf from Tim662. And they are right. It is not exactly clean and certainly not clean and powerful at the same time. Your responses already seem a little loaded/inflammatory. John has his own ideas about Class D but what he said was pretty much on point and certainly not deserving of such a tough response. I am a kiwi as well but its important to show our respect for our Aussie counterparts LOL. More seriously why are you not interested in cleaner/powerful Class D options? All good that you are not, just might give people a little better idea to help you out?

 

[tomtoo]

What a strange thread *facepalm*

 

[Bruce Morgen]

I have two A07s and they are fantastic given how dirt-cheap they are. Of course I will never need anywhere near the TPA3255 data sheet's rated power -- the one I push the hardest (into nominal 4 ohm loads) is powered by a 48VDC @10A SMPS (with an extra 1000uF of shunt capcitance across its output) that never gets warm enough to turn on its cooling fan. I dimed the SMPS's voltage control so it puts out 49 volts unloaded -- when I push the A07 as hard as I can without going deaf, that number falls to about 46.5 volts. Subjectively speaking, that setup vastly outperforms the widely-acclaimed, Nelson Pass designed Adcom GFA-535 I swore by back in the day. Of course, its distortion spec isn't SOTA -- but it's more than decent, and a lot better than the Kenwood KM-8002 I enjoyed using for years before getting that Adcom, all the while putting out a lot more wattage. Incidentally, the A07, has a 5.5mm coaxial power socket -- 2.5mm is the center pin diameter, and given the very intermittent current demand of a Class D amp IMO that's entirely adequate. If we were talking about the steadier two-digit current requirements of an LED array -- or, for that matter, a Class AB amp -- that would be another story entirely and a more robust connector would be in order.

 

[Tangband]

I'm just curious if anyone has measurements/a performance analysis of the following:

https://www.aiyima.com/products/amplifier-aiyima-a07-tpa3255-2-0-channel-300wx2-hifi

I'm quite tempted to purchase one as I've heard good things about the TPA325x series of amplifier chips, and I like inexpensive, clean and powerful amplification. By the way, I'm not looking for suggestions regarding other amps.

Thanks in advance

Here are measurements .
They are good !
https://www.diyaudio.com/forums/class-d/362498-aiyima-a07-tpa-3255-measurements.html

 

[Tangband]

@Tim6622 linked the datasheet. You should read it perhaps, instead of dismissing what was an intelligent and useful post. If you just want people to agree with you, and chastise them for another view, this isn't the place.

The performance of the TPA-3255 is not good. It's rather noisy (160uV is ten times what a good amp can deliver), has high THD and the rated power output of the device in question cannot be achieved with the rated power supply range they suggest.

To get even close to the spec, you'd need a 51V 650W supply, which would need to deliver nearly 13A through a 2.5mm DC coaxial power plug- something that would just never happen.

This is entirely wrong .
The measurements of Aiyima a07 tpa3255 is better than Behringer A800. Except for power.

 

[Tangband]

I have two A07s and they are fantastic given how dirt-cheap they are. Of course I will never need anywhere near the TPA3255 data sheet's rated power -- the one I push the hardest (into nominal 4 ohm loads) is powered by a 48VDC @10A SMPS (with an extra 1000uF of shunt capcitance across its output) that never gets warm enough to turn on its cooling fan. I dimed the SMPS's voltage control so it puts out 49 volts unloaded -- when I push the A07 as hard as I can without going deaf, that number falls to about 46.5 volts. Subjectively speaking, that setup vastly outperforms the widely-acclaimed, Nelson Pass designed Adcom GFA-535 I swore by back in the day. Of course, its distortion spec isn't SOTA -- but it's more than decent, and a lot better than the Kenwood KM-8002 I enjoyed using for years before getting that Adcom, all the while putting out a lot more wattage. Incidentally, the A07, has a 5.5mm coaxial power socket -- 2.5mm is the center pin diameter, and given the very intermittent current demand of a Class D amp IMO that's entirely adequate. If we were talking about the steadier two-digit current requirements of an LED array -- or, for that matter, a Class AB amp -- that would be another story entirely and a more robust connector would be in order.

Amirms latest test is tpa3255 based !
This is the power amp performance:

https://www.audiosciencereview.com/forum/index.php?threads/minidsp-shd-power-amplifier-review.17586/

 

[Biblob]

Not today, John. I don't like you, I don't respect you, and I wouldn't listen to if you were the last person on Earth.

A bit late to the party, but I don't think these posts are doing the forum any good. If you don't agree, there is no reason to get so personal about it. Respectfully conversating is the least you can do.

 

[restorer-john]

This is entirely wrong .

Which part?

Waiting.....still...waiting.

Amirms latest test is tpa3255 based !
This is the power amp performance:

At a measly 5W. Wow, let's break out the champagne. What a joke.

160uV of noise. A-WTD. Give me a break.

And the thing shut down when doing a simple power output test. It's a toy.

Get a real big boy amplifier and stop p#ssing around in the shallow end of the toddlers' wading pool.

 

[dominikz]

I'm just curious if anyone has measurements/a performance analysis of the following:

https://www.aiyima.com/products/amplifier-aiyima-a07-tpa3255-2-0-channel-300wx2-hifi

I'm quite tempted to purchase one as I've heard good things about the TPA325x series of amplifier chips, and I like inexpensive, clean and powerful amplification. By the way, I'm not looking for suggestions regarding other amps.

Thanks in advance

Not Aiyama A07, but measurements of the TI TPA3255 EVM are available on the QuantAsylum blog - maybe those can be used as another datapoint:
https://quantasylum.com/blogs/news/ti-tpa3255-evm

 

[Bruce Morgen]

Which part?

Waiting.....still...waiting.



At a measly 5W. Wow, let's break out the champagne. What a joke.

160uV of noise. A-WTD. Give me a break.

View attachment 94108

And the thing shut down when doing a simple power output test. It's a toy.

Get a real big boy amplifier and stop p#ssing around in the shallow end of the toddlers' wading pool.

Which part of this sub-$50USD (shipped!) "toy" audibly outperforming two well-regarded vintage power amps didn't you understand? The TPA3255 is major technical achievement given its minuscule physical size, absurdly low cost, and the genius-level circuit sophistication it packs into a tiny bit of silicon. Look how much has to go into an entry-level IcePower OEM module to surpass it by a margin so small that most of the self-styled "audiophile" contingent would be hard-pressed to hear any significant difference all else being equal. There's a reason Bruno Putzeys hired a big chunk of TI's TAS/TPA team to work with him at Purifi -- those guys are absolutely first-rate and know exactly what they're doing. Of course you can spend 10x the money on an IcePower/Hypex-based power amp and get better results than with an A07 -- but when it comes to pure price/performance ratio, the little "chip amp"+SMPS combination wins in a walk.

 

[ModDIY]

160uV of noise. A-WTD. Give me a break.

How good do you think the rate is? I do not know this measurement, out of curiosity ... thank you

 

[AnalogSteph]

How good do you think the rate is? I do not know this measurement, out of curiosity ... thank you

So-so. Not terribly bad for something 300+ W actually, but considering that you could buy 250 W power amplifiers with 35 µV(A) 30 years ago and that even a fair few integrated amps with their much higher gain make it to 80-110 µV(A), it's not particularly awe-inspiring.

160 µV(A) is -85 dB(A) ref. 2.83 V, or in terms of Amir's standard metrics, a dynamic range (upper bound for SINAD) of 89 dB(A) ref. 5 W / 4 ohm.

For comparison, this would be the equivalent to the noise of a consumer-level (2 Vrms) DAC with 103.4 dB(A) of dynamic range when attached to a theoretical noiseless amplifier of same gain (21.5 dB). No fancy DAC needed here, something in the $100 class (or a $40 internal card) will do perfectly fine if you don't already have something suitable.

It still is plenty good enough for fullrange speakers up to ~89 dB of sensitivity (which, quite frankly, is a majority of them), or just about any bass drivers, at least as long as they are cones anyway.

 

[ModDIY]

Thanks for the detailed explanation. It gives me a better idea.

 

[Bruce Morgen]

So-so. Not terribly bad for something 300+ W actually, but considering that you could buy 250 W power amplifiers with 35 µV(A) 30 years ago and that even a fair few integrated amps with their much higher gain make it to 80-110 µV(A), it's not particularly awe-inspiring.

160 µV(A) is -85 dB(A) ref. 2.83 V, or in terms of Amir's standard metrics, a dynamic range (upper bound for SINAD) of 89 dB(A) ref. 5 W / 4 ohm.

For comparison, this would be the equivalent to the noise of a consumer-level (2 Vrms) DAC with 103.4 dB(A) of dynamic range when attached to a theoretical noiseless amplifier of same gain (21.5 dB). No fancy DAC needed here, something in the $100 class (or a $40 internal card) will do perfectly fine if you don't already have something suitable.

It still is plenty good enough for fullrange speakers up to ~89 dB of sensitivity (which, quite frankly, is a majority of them), or just about any bass drivers, at least as long as they are cones anyway.

Considering the cost of those 1990s amplifiers in inflation-adjusted USD compared to less than $50USD (shipped, plus the modest cost of a suitable SMPS) for something like an A07 and how much more it would cost to get an audible performance upgrade, I'd say it's actually pretty awesome in that context. In my experience, the A07 was more than quiet enough to easily hear the lowering of the noise floor when I switched from my PeeCee's internal Realtek sound chip to a very modest external DAC, so I wouldn't count on a "$40 internal card" being an appropriate source. Then there's the size and power consumption advantages of Class D with an SMPS, not to mention less than perfectly quiet listening environments, e.g. a typical desktop/nearfield setup like mine, with its constantly-running PC fan(s).

So -- is a TPA3255-based amp SOTA as a pure audio performer? Obviously not, and for Class D amplification that fits into that category you'd clearly need to spend more -- a lot more -- for an ICEpower-, Hypex-, or Purifi-based solution. That said, does it qualify as "hi fi?" IMO by any sensible definition it certainly does, and going strictly by price/performance ratio, it's damned near miraculous!

 

[tomtoo]

"..13A through a 2.5mm DC coaxial power plug- something that would just never happen..."

What is the specification for this plugs?