AIYIMA A07 TPA3255 Review (Amplifier)

[Lambda]

You still couldn't explained to me why I would be the 7001 customer that would get his house burnt down while the others 7000 didn't. If these items from the sellers are so dangerous then there would be reviews showing damages already.

It is not a big achievement not to burn down a house even if you don't follow safety standards and tests.

It has GS, TÜV and FCC logo.
So go on and ask the seller for the certificate and the FCC ID i’m waiting

 

[Bruce Morgen]

The price just jumped to $80!

IMO it was obviously a seller posting error in the first place.

 

[Lambda]

Apparently it is important from the efficiency point of view. Ie, the output/input power ratio (thus how much heat is dissipated by the amp chip) does depend on input voltage (It’s in the chip spec).

I don't see input voltage vs. efficiency in the datasheet.?

But its but its probably not a huge difference.

 

[imagidominc]

I am using these and I am happy with the quality but they are on Amazon.
GearIT Banana Plug Connectors, Closed Screw, 24K Gold Plated, 6 Pairs, 12 Pieces: Amazon.ca: Electronics

I’ll look into it! Thank you Steamrolly and Bruce Morgen!

 

[Raindog123]

I’d like to hear someone’s input who has more experience with this than I do. I’m worried about buying a banana plug that doesn’t fit the posts.

I’ve repurposed lab patch cables with banana plugs (to be used on the amp side):

 

[imagidominc]

I’ve repurposed lab patch cables with banana plugs (to be used on the amp side):

View attachment 118091

Looks cool! I love the color coordination!

 

[Raindog123]

It is not a big achievement not to burn down a house

You were making good points... until it turned to pure scare tactics...

We are all big boys and girls here, and understand difference between the certified and uncertified products. And the associated potential risks. But not all (most, many) uncertified products will necessarily burn in flames. And, as it was pointed out, we do use mass-produced electronics all the time. And I’ve heard about fully certified/QA’d products catch fire... Heck, I work for Boeing, and our planes still fell out of the skies once in a while. And Asian-produced t-shirts might irritate skin, yet all world still wears them... Again, there is common sense, and there is paranoia.

 

[Raindog123]

But its but its probably not a huge difference.

But it is... Here, just run a simple test - Played "Bromberg Plays Hendrix" for 1 hour each, with two of my power supplies. The same volume (though it does not really matter), 80F ambient temperature:

Here is my 36V 4A rated PS (from Amazon Prime):

And here is 48V 3A rated (still amazon prime):

...think what you want.

 

[Raindog123]

Are you getting the full potential from the amp in terms of power ,distortion,SIAND. No
Is it emitting lots of Noise. Probably.

Just to remind you (and everyone) that Amir measured A07 with this very (well, very similar) power brick. So, as far as SINAD and distortion are concerned, we have the measurements. And they are superb!

Yeah, sure looking foreword to your test of the load regulation and EMC, till then let me tell you this is crap.

Ok, I will take my eBay 48V 5A brick to the lab on Mon. Run it through 15Ohm and 10Ohm loads for a while... (In a fire safe environment, I promise. ) Will report what happens, and how fast it catches fire...

 

[restorer-john]

Just to remind you (and everyone) that Amir measured A07 with this very (well, very similar) power brick. So, as far as SINAD and distortion are concerned, we have the measurements. And they are superb!

They are not remotely 'superb'. That's just complete BS. Not even good. Low price is not an excuse where fidelity is concerned.

People really need to stop talking up this little toy amplifier as being anything other than a 'my-first-amplifier' for a kids bedroom or maybe an amplifier for a dorm room at college. Nah, not even that. I had serious amplifiers in my college room back in the day.

 

[Raindog123]

They are not remotely 'superb'.

Resting smiling pink panther is 'remotely superb' in where I live... DIXI

(I bet you're not from Melbourne!? )

I had serious amplifiers in my college room back in the day

...but I bet all-electric cars did not drive themselves, and $5 DAC chips did not have TDH+N of -120dB “back in the days”!?

 

[Bruce Morgen]

They are not remotely 'superb'. That's just complete BS. Not even good. Low price is not an excuse where fidelity is concerned.

People really need to stop talking up this little toy amplifier as being anything other than a 'my-first-amplifier' for a kids bedroom or maybe an amplifier for a dorm room at college. Nah, not even that. I had serious amplifiers in my college room back in the day.

Give it a rest, John. Expecting a tiny amp with a tiny price tag to perform as per the SOTA -- even the 1970s SOTA -- is idiotic. Where the A07 is definitely "superb" is its price-performance ratio -- and it honestly sounds better than the highly regarded Nelson Pass-designed "audiophile" Adcom GFA-535 I swore by back in the 1980s and 1990s. As for "fidelity," the little wonder has the same SINAD as a
$1499 USD "high end" PS Audio monoblock and a similar impedance-dependent frequency response curve! I reiterate, give it a rest!

 

[boselover61]

Every chifi thread has a bunch of critics in it. I wonder why

 

[restorer-john]

Give it a rest, John. Expecting a tiny amp with a tiny price tag to perform as per the SOTA -- even the 1970s SOTA -- is idiotic. Where the A07 is definitely "superb" is its price-performance ratio

What's 'idiotic' (no need to be rude, BTW) is heaping praise on this POS. No way does it qualify as HiFi. It's not even worth review time other than for a good laugh.

IMO it only serves to make ASR look like a bit of a joke and certainly does no favours for the membership who clamour mindlessly to buy it, letalone reccommend it to their hapless friends.

It is advertised by the manufacturer as a 300+300 watt amplifer. I called it months ago, long before Amir's review. At what point do you call it for what it is? Deceptive and plain false and misleading specifications. In most countries, such claims are illegal. And yet on ASR it gets praise?

So here are the official specs:

Does it achieve 300+300W? Not even close, not with any supply. (see the review)
Does it achieve 110dB S/N at full power? Not even close (see the review)
Does it achieve THD+N of 0.008%? Between 5w and 10w it just scrapes in. At all other power levels not even close. (see the review).

So, no free rides and certainly zero praise from me. And yes, I bought a few little Class D things in pretty boxes to play with. Tested them and tried to give them away. Even my boys rejected them.

 

[boselover61]

Thanks for sharing your opinion, john restorer.

 

[Bruce Morgen]

What's 'idiotic' (no need to be rude, BTW) is heaping praise on this POS. No way does it qualify as HiFi. It's not even worth review time other than for a good laugh.

IMO it only serves to make ASR look like a bit of a joke and certainly does no favours for the membership who clamour mindlessly to buy it, letalone reccommend it to their hapless friends.

It is advertised by the manufacturer as a 300+300 watt amplifer. I called it months ago, long before Amir's review. At what point do you call it for what it is? Deceptive and plain false and misleading specifications. In most countries, such claims are illegal. And yet on ASR it gets praise?

View attachment 118111

So, no free rides and certainly zero praise from me. And yes, I bought a few little Class D things in pretty boxes to play with. Tested them and tried to give them away. Even my boys rejected them.

I apologize for the ill-considered word choice.

Those of us who know the "Chi-Fi" game are aware that the advertised specs are codswallop and entirely beside the point -- we know what we're buying and what we can reasonably expect. There are a great many products that cost many -- even dozens of -- times the price of an A07 and don't perform any better, e.g. the uber-hyped PS Audio Sprout100 and pretty much anything based on the "entry-level" ICEPower Class D modules -- save your ire for them. Enough said.

 

[Raindog123]

Speaker current is not equal power supply current with class D!

I do not think anyone argued with this anywhere on the 30 pages of this thread. So, glad you came to realize it too!

And now... fun fact, speaker current actually is proportional to the power supply current. This is due to the fundamental energy conservation principle. I think, what you meant to point out is that the power supply maximum (aka ”rating”) current is not equal to the speaker current - determined by the speaker impedance and amplifier’s volume knob position. But again, thanks, we already knew that.

 

[HorizonsEdge]

so this got interesting . . . again )

According to Texas Instruments . . . . (https://www.ti.com/lit/ds/symlink/tpa3255.pdf)

3 Description TPA3255 is a high performance class-D power amplifier that enables true premium sound quality with class-D efficiency. It features an advanced integrated feedback design and proprietary highspeed gate driver error correction (PurePath™ UltraHD). This technology allows ultra low distortion across the audio band and superior audio quality. The device is operated in AD-mode, and can drive up to 2 x 315 W into 4-Ω load at 10% THD and 2 x 150 W unclipped into 8-Ω load and features a 2 VRMS analog input interface that works seamlessly with high performance DACs such as TI's PCM5242. In addition to excellent audio performance, TPA3255 achieves both high power efficiency and very low power stage idle losses below 2.5W. This is achieved through the use of 85 mΩ MOSFETs and an optimized gate driver scheme that achieves significantly lower idle losses than typical discrete implementations.

I just wanted to clear up the contested point regarding where the performance claims come from. Not really sure what the revision history is since this does not explicitly say 300x300 and instead says 315x315 among other things. SO . . . take up your beef with the engineers at TI or maybe a regulator. You know publicly traded company (NASDAQ: TXN)

and full disclosure; I own this amp and use it in my desktop system. I have never even heard what a "high end" amplifier sounds like but out of the handful of sub-$500usd solutions I have heard this is as good or better than all of them. I am currently a satisfied customer. Some in this thread might consider me an ignorant customer. I was going to offer a caution on the hazards of uncompromising standards and where that rabbit hole can lead but I decided that it was so self evident as to be unnecessary.

I do appreciate the conversation! Not much else I can do when the newborn in the next apartment decides to wake up the building at 3am (again /sigh)

Cheers

 

[restorer-john]

I just wanted to clear up the contested point regarding where the performance claims come from. Not really sure what the revision history is since this does not explicitly say 300x300 and instead says 315x315 among other things. SO . . . take up your beef with the engineers at TI or maybe a regulator.

You do realize the IC specifications and the completed Aiyima product are two completely different things?

TI use a 51V supply, THD at 10% and clearly a power supply that would cost multiples of the price of this Aiyima thing. Then for the maximum 8R spec they use a 53.5V supply.

The completed product being sold and reviewed here, as supplied, cannot achieve its rated specs. Not even remotely close. It is the customers that buy based on published specifications that are being deceived and ripped off.

 

[HorizonsEdge]

You do realize the IC specifications and the completed Aiyima product are two completely different things?

TI use a 51V supply, THD at 10% and clearly a power supply that would cost multiples of the price of this Aiyima thing. Then for the maximum 8R spec they use a 53.5V supply.

The completed product being sold and reviewed here, as supplied, cannot achieve its rated specs. Not even remotely close. It is the customers that buy based on published specifications that are being deceived and ripped off.

I have to apologize. I was trolling you and you did not disappoint. My bad!