AIYIMA A07 TPA3255 Review (Amplifier)

[TheBatsEar]

Is this for a new product or a used one at such a low price ?

Not sure about the prices, but let me say welcome at ASR.

 

[HappyMetalGuy]

Is this for a new product or a used one at such a low price ?

Hi it's from zococity.es open box, for Portugal it's free shipping. They arrived today tested everything and they look and feel new (didn't test the balanced input on PA3s).

 

[ddaudio]

I'm from what should probably be called the dark ages of hi-fi, when we would first judge amplifiers by their weight. My living room system is based around a giant 20kg (44lb) Pioneer receiver which was tested in its day to be capable of dynamic power of 280 Watts into 4 ohms (and 450 Watts into 2 ohms). Test report here: http://www.milleraudioresearch.com/download/reports/aug04/pioneervsxax5i.html

This week, I started looking for a headphone amp for late night listening, became curious about what these mini amps could do, so ended up, with the help of this forum, with a SMSL C100 DAC, Aiyima A07 amp and a Sabaj A10h headphone amp, all for the princely sum of 215GBP. (The Sabaj is still on its way).

I started by going through the amplifier power requirement test here http://archimago.blogspot.com/2017/09/musings-how-much-amplifier-power-do-you.html and worked out my real world power needs were well within the capabilities of the Aiyima A07 with its stock 32V 5A power supply.

My speakers are the Dynaudio Contour 1.3 mk2, a 25 year old high quality bookshelf design, 86db/2.83v/m sensitivity, said at the time to be fairly current hungry but a not particularly reactive load. Here are the impedance/phase measurements from its Stereophile test:

View attachment 288179

I am also using a Marantz PM66KIS amp which I recently got out of storage - this is rated at 70 wpc into 4 ohms but was tested to deliver 132. This was the amp I was using when I first bought the Dynaudio speakers. It, and the Pioneer receiver, drive them very nicely indeed. As does a Naim XS integrated amp which I have in my study, currently hooked up to some Tannoy dual concentrics.

So what do I think of the results? In a word, eye-opening for this old dinosaur. As predicted, the Aiyima drives the speakers to any level you could possibly want in my room, and I listen to a lot of classical music, so require a very high dynamic range. The sound is very clean, no noise audible in use - I turned the amp up to max gain with no music playing and pressed my ear against the tweeter and there was only a barely perceptible hiss (albeit with my old ears which hear nothing above 12khz). This is a big improvement over the aging Marantz - when I got it out of storage I had to open it up and clean the switch contacts inside (it's all mechanical) and it still crackles slightly with the same ear-to-tweeter test. More Importantly, the Marantz has a big toroidal transformer which buzzes randomly (not through the speakers, not level-dependant - presumably DC on the mains) - when it happens it can be heard even when wearing headphones. There's none of that with the Aiyima.

I've currently got the SMSL DAC connected to the Aiyima, with the amp's useful passthrough AUX out connected to the Marantz amp. I have a switch to allow the speakers to be switched from one amp to the other. I'm A-B testing, obviously not blind (though by tomorrow I might have forgotten which is which on the switch!), and it's the usual psychoacoustic story: Switch from one to the other and it sounds better. Then switch back and it sounds better still (how many times do you need to switch before it sounds better that the original performance?). More seriously, this tells me the A07 is very good indeed and I'm using it well within its capabilities even with the stock power supply.

When the Sabaj headphone amp arrives, I intend to connect the DAC directly to it, and drive the A07 from the Sabaj's line out, which as tested in this forum has a very high quality volume control, independently adjustable for the HP/line out, and with remote control. I could even connect an analogue source to the Aiyima AUX socket, If I wanted, just for fun. I'm looking forward to it.

Well, the Sabaj A10h finally turned up (I think when you order it from "the UK warehouse" it means via the UK warehouse - it still originates in China, but no problems with import duties/tax).

My replay chain is now SMSL C100 --> Sabaj A10h --> A07 --> speakers (or C100 --> A10h --> headphones), and all is good - still no audible noise except the tiniest bit of hiss when pressing an ear against the tweeter with all volume controls set to maximum (there's a scientific measurement for you!)

But I'm a bit overloaded with volume controls. For speaker listening I've started with the DAC set to max and the A07 set to 12 o'clock, which gives me a bit more volume that I'd ever need with the Sabaj on the H1 (0db gain) setting - useful range is then -40db to 0db on its volume display.

Is this about the right approach? What effect would raising my set volume on the A07 (with a corresponding reduction in the input level from the Sabaj) have on:

1. A07 power consumption/heat generation?
2. A07 channel balance - it the pot volume better matched at levels above 12 o'clock?
3. A07 distortion levels?

 

[TonyJZX]

i have a set right now that has dac w/ remote -> preamp w/ remote -> poweramp w/ remote

i would set dac to max (except when using headphones)

preamp as the main vol. control

poweramp to low to minimise noise

it really depends on what your favored remote source is if you use it

i reckon the "noisiest" item you have the A07... the Sabaj and smsl are really quiet in comparison so take it from there

 

[ddaudio]

i have a set right now that has dac w/ remote -> preamp w/ remote -> poweramp w/ remote

i would set dac to max (except when using headphones)

preamp as the main vol. control

poweramp to low to minimise noise

it really depends on what your favored remote source is if you use it

i reckon the "noisiest" item you have the A07... the Sabaj and smsl are really quiet in comparison so take it from there

Thanks. I can keep the DAC at max, even with headphones, as the Sabaj has independent volume control of the HP and RCA outs.

 

[HappyMetalGuy]

All I decide to buy RA3. Write down your initial feelings. I am especially interested in whether there is background noise and whether there are audible clicks when the amplifier is turned off and on.

Just tested the power on and off with maximum level and there is a minor "click" heard no problem for me, on the A07 I don't ear any click but the toggle switch makes as much noise has the the click heard in PA3s . I cannot hear any background noise from the Mission LX2 MKII with volumes max out on DX3 Pro+ and PA3s.

 

[HappyMetalGuy]

thanks for the answer. A small click appears when you turn it off with the toggle switch ? Or when you turn off the power from the outlet, while not using the toggle switch?At 07, I also did not hear clicks. I have Dynaudio dm 2/7 and 3/7 .... Very clean background at 07. Most likely from the low sensitivity of acoustics at 86db.

There's no click heard on the speakers with A07. A very small click is heard from the speaker with PA3s. Now I have 2 system's for nearfield listening one in my work office (Aiyima A07 + SMSL SU-1 + Dali Oberon 1 + Creative Labs Subwoffer) really like this combo. The other one in my garage (Topping PA3s + DX3 Pro+ Mission LX2 MKII) still a work in progress. Bought a cable TRS to RCA female just to test the balanced input on the PA3s (not going to connect anything balanced just a PS-LX310BT from Sony) lets see if I'll add a subwoffer here also, maybe not because the Mission's feels to have a little more bass then the Dali's.

 

[Doodski]

@ruslan6060 if you type the "@" sign and then start typing the persons nikname (@happ) you will see options for the nikname selection.

 

[HappyMetalGuy]

HappyMetalGuy: Will I get better sound at low volume with Topping PA3 than with Aiyima 07?

Well "subjectively" I don't think there's much of a difference between the two, I like them both. If you really want an upgrade "probably" the Topping PA7 can be a significant step towards better sound but then you have to take in consideration the speaker limitation. The one think that separates them is that the A07 has the aux 3.5mm out/in and you can use it for a active subwoofer or another analog input (not both at the same time) the PA3s has two analog inputs one of which is balanced.

 

[375HP2482]

Will I get better sound at low volume with Topping PA3 than with Aiyima 07?

Short answer: No.

Long answer: No, you will not get better sound at low volume with any amplifier versus the A07.

 

[ddaudio]

I've been wondering about the reports of heat generated by the SMPS - mine doesn't get hot at all, with constant use. I'm in Europe - could it be the difference in mains voltage compared to the USA? I presume that (given equal efficiency) half the input voltage will mean it draws twice the current for a given output power.

 

[Joe Smith]

@375HP2482 I carefully read both branches of both Aiyima 07 and Topping pa3s and it seemed to me that it was at low volume that Topping sounds more accurate. Less background, less noise and so on. I want to pick up an amplifier in the bedroom that will give Dynaudio dm 2/7 acoustics a good and comfortable sound at low volume. Clean and without distortion or noise. I wanted to buy Topping pa3s for this purpose. But after your post, now I doubt it. Aiyima 07 I gave to a friend. And I wanted to take something better and not much more expensive. I don't need a lot of power in the bedroom. In Aiyima 07, I do not like that in different batches there may be different quality of radio components.

It's a really good little amp, good at low volumes; I think you're getting sidetracked worrying about the specific caps, etc. The only major caps issue that merits caution is if you plan to try to use a very high power supply for it, but with softer levels, that should not be a concern.

Or you can wait for the Fosi V3 amp, which is due to be released on June 20 - where they are emphasizing component quality and the ventilation holes.

 

[HappyMetalGuy]

Or you can wait for the Fosi V3 amp, which is due to be released on June 20 - where they are emphasizing component quality and the ventilation holes.

The big problem with Fosi V3 amp is that is design for and I quote "Fosi Audio V3 - 2-Channel Stereo Power Amplifier Designed for HiFi Audiophiles"
I hope they release a version for audiosciencereview community and other's alike.
Fosi Audio V3 -discussion (Fosi V3)

 

[375HP2482]

@375HP2482 I carefully read both branches of both Aiyima 07 and Topping pa3s and it seemed to me that it was at low volume that Topping sounds more accurate. Less background, less noise and so on.

Your speakers are 86 dB sensitive, as are mine and most others. At that sensitivity the noise from the A07 can be barely perceived with an ear directly contacting the grille, and the distortion components would be at a similar level of audibility -- plus they are somewhat masked by the signal itself. Based on measurements and internal appearance, the A07 and others like it that are apparently based on the original Texas Instruments design will have similar performance.

I don't need a lot of power in the bedroom. In Aiyima 07, I do not like that in different batches there may be different quality of radio components.

I'm not aware of anyone who has performed competent testing of the A07's components. It's not unusual for manufacturers to use different vendors. Usually "quality of components" is a dog-whistle meaning brand-name capacitors (Japanese) instead of more recent Chinese suppliers. These days a wide array of popular audio products (like my Yamaha AVR and JBL speakers) are "Made In China."

 

[-Jim-]

Gents,

Reviews for the Fosi V3 are popping up all over YouTube. This one in particular caught my eye as it's by a member from here.

I noticed the direct comparisons to the A07 as it's the obvious benchmark for it to surpass. I was wondering if there is a thread here where members have photos of their modified A07 cases to improve cooling. I really haven't had time to run mine too much since purchase (with the stock 32 volt PSU), but so far it runs very cool.

 

[Talisman]

I noticed the direct comparisons to the A07 as it's the obvious benchmark for it to surpass.

Honestly, already the Bt20a Pro had scored a notch higher in performance than the Aiyima. The V3 is only increasing the distance but Fosi has already made the pass

 

[trungdtmc]

I replaced 3255 chip by 3251. Sound is better and better. Haha

 

[antcollinet]

I replaced 3255 chip by 3251. Sound is better and better. HahaView attachment 294347

Nice soldering work.

Far from convinced though that the sound will be audibly different. Having said that - it'll be very difficult to ABX

 

[TheBatsEar]

I replaced 3255 chip by 3251. Sound is better and better. HahaView attachment 294347

That's crazy! I had to replace a SMD fuse on a 3D printer board once, it wasn't easy.
Anything in the specs that made you think it would sound better? Where did you get the chip and what did you pay?

 

[Grooved]

I replaced 3255 chip by 3251. Sound is better and better. HahaView attachment 294347

What PSU do you use? one of the difference between 3255 and 3251 is 3255 has 18-53.5V supply voltage operation and 3251 has 12-36V only
Since measurements gave better results with higher voltage PSU with the 3255, it's possible that a 36V PSU with a 3251 would give higher results than the same 36V PSU used with a 3255

Anyway, it's interesting but it would be great to get subjective feedback AND measurements