AIYIMA A07 TPA3255 Tear Down

[Scrufboy]

sound when add more capacitor did not change, just for sure at high power it better, my choose, but then i had removed it, haha

Would like full parts list. Maybe even assistance of some kind... Very interested in modifying these amps.

 

[Gaspar74]

I’m in process of installing this Aiyima board in a different chassis. The chassis I have has a power button two leads however the stock Aiyima is this. Anyone know the wiring of the new switch replacing the one on stock?

 

[Honu]

Hi guys,
I got a question for you, i'm living in an off grid house, and i pwoer it with a LiFePo4, the voltage is between 48V and 54V, do you think The A07 could work with it ? Or is 54 too high..? It's like 10% more then the 48V rated voltage ...
But i would like to avoid a converter ....

 

[Bushellj]

Hi guys,
I got a question for you, i'm living in an off grid house, and i pwoer it with a LiFePo4, the voltage is between 48V and 54V, do you think The A07 could work with it ? Or is 54 too high..? It's like 10% more then the 48V rated voltage ...
But i would like to avoid a converter ....

You may want to check the voltage rating of the internal components - Specifically the main capacitors and the voltage regulator chip.

When the batteries are being charged the voltage can go way above the 54 Volts especially if you are charging from Solar Panels. Actually a DC to DC Power Converter might be a very good solution to providing a nice safe stabilised supply to the A07. They are not expensive and any half decent one is unlikely to introduce any noise into the Audio side of things. That said of course you probably already have a 240 Volt supply and therefore can use any good switching power supply like the Mean Well LRS 200 series. I would use a 36 volt one and turn up the voltage on the adjuster if required or a 48 Volt one and turn it down a bit just to stay on the safe side of the A07 components.

I appreciate you were probably trying to take advantage of the nice smooth power from the batteries !! Keep in mind that if you already have mains converters in the system that there will already be switching noise present even on the battery supply so actually a DC converter or switching power supply is likely to produce less noise at the amplifier !!

A simple solution would be to put some power diodes in series with the power supply. Each one would drop the voltage by a volt or so and hence bring the voltage seen by the A07 to an acceptable and safe level. BUT as said earlier be aware that there might be higher voltages present that would still kill the A07 !!

 

[John4949]

Hello everyone, I had a question to ask about this Aiyima A07 amp: I plan to replace several components as "trungdtmc" did. I only know a little about electronics and I'm afraid when desoldering the two 1000uf/50V capacitors that they remain charged with electricity (because I would have tried the amp when I receive it) and that I receive a big electric shock in the hand and the arm. Is there really a risk that these two capacitors will remain positively charged even after an hour after turning off and then unplugging the Aiyima A07 amplifier. If yes, what would be the solution to discharge the two capacitors???? I also plan to replace the 9 small 10uF capacitors but I think for those there they must discharge when the amp is no longer powered. Thanks for your help. Best wishes for this year 2023!

 

[Doodski]

Hello everyone, I had a question to ask about this Aiyima A07 amp: I plan to replace several components as "trungdtmc" did. I only know a little about electronics and I'm afraid when desoldering the two 1000uf/50V capacitors that they remain charged with electricity (because I would have tried the amp when I receive it) and that I receive a big electric shock in the hand and the arm. Is there really a risk that these two capacitors will remain positively charged even after an hour after turning off and then unplugging the Aiyima A07 amplifier. If yes, what would be the solution to discharge the two capacitors???? I also plan to replace the 9 small 10uF capacitors but I think for those there they must discharge when the amp is no longer powered. Thanks for your help. Best wishes for this year 2023!

Capacitors from what I have expereinced can hold a charge for several days+ if they don't have a bleeder resister in circuit. Use a discharging resister, perhaps a 5 Watt resister at ~200 Ohms. The 5W is suggested because the discharge resister can get very hot and do that very quickly so that one second you are holding a cold resister and in seconds it can heat up to the degree that you burn your fingers. So the 5 Watt size is suggested so that they can handle more heat without burning you as you discharge those capacitors.

 

[Honu]

You may want to check the voltage rating of the internal components - Specifically the main capacitors and the voltage regulator chip.

When the batteries are being charged the voltage can go way above the 54 Volts especially if you are charging from Solar Panels. Actually a DC to DC Power Converter might be a very good solution to providing a nice safe stabilised supply to the A07. They are not expensive and any half decent one is unlikely to introduce any noise into the Audio side of things. That said of course you probably already have a 240 Volt supply and therefore can use any good switching power supply like the Mean Well LRS 200 series. I would use a 36 volt one and turn up the voltage on the adjuster if required or a 48 Volt one and turn it down a bit just to stay on the safe side of the A07 components.

I appreciate you were probably trying to take advantage of the nice smooth power from the batteries !! Keep in mind that if you already have mains converters in the system that there will already be switching noise present even on the battery supply so actually a DC converter or switching power supply is likely to produce less noise at the amplifier !!

A simple solution would be to put some power diodes in series with the power supply. Each one would drop the voltage by a volt or so and hence bring the voltage seen by the A07 to an acceptable and safe level. BUT as said earlier be aware that there might be higher voltages present that would still kill the A07 !!

Helloo,

My pack do not go over 54.4, let's say 55V, even under charge.
No DC-DC converter work .. well .. they do .. but not to have 48V cause my pack go from 48 to 55v and they need some gap between the inpout and output .. the ones i seen at least. For the time being i ordered a 40-60V => 36V DC to DC converter.
I do not want to use AC, cause i switch off the inverter at night and would like to keep the posibility to listen to music at night.
Understood about DC being poluted by other devices on the DC circuit, i got 2 DC-DC converters feeding 3 differents circuits, one 12V (some specific devices woring 24h24, router, NUC... ), one 24V (lights) and one 48V-55V.

Now .. i could build a specific battery pack for music with only 14 cells => 48V max.

Yea but that would be a lot of diodes ... to "eat" those 7V... like 8 diodes, seems a lot.

 

[trungdtmc]

Hello everyone, I had a question to ask about this Aiyima A07 amp: I plan to replace several components as "trungdtmc" did. I only know a little about electronics and I'm afraid when desoldering the two 1000uf/50V capacitors that they remain charged with electricity (because I would have tried the amp when I receive it) and that I receive a big electric shock in the hand and the arm. Is there really a risk that these two capacitors will remain positively charged even after an hour after turning off and then unplugging the Aiyima A07 amplifier. If yes, what would be the solution to discharge the two capacitors???? I also plan to replace the 9 small 10uF capacitors but I think for those there they must discharge when the amp is no longer powered. Thanks for your help. Best wishes for this year 2023!

you simple unplugging while still turn on the switch , the red LED would sign the power remain

 

[Honu]

You may want to check the voltage rating of the internal components - Specifically the main capacitors and the voltage regulator chip.

When the batteries are being charged the voltage can go way above the 54 Volts especially if you are charging from Solar Panels. Actually a DC to DC Power Converter might be a very good solution to providing a nice safe stabilised supply to the A07. They are not expensive and any half decent one is unlikely to introduce any noise into the Audio side of things. That said of course you probably already have a 240 Volt supply and therefore can use any good switching power supply like the Mean Well LRS 200 series. I would use a 36 volt one and turn up the voltage on the adjuster if required or a 48 Volt one and turn it down a bit just to stay on the safe side of the A07 components.

I appreciate you were probably trying to take advantage of the nice smooth power from the batteries !! Keep in mind that if you already have mains converters in the system that there will already be switching noise present even on the battery supply so actually a DC converter or switching power supply is likely to produce less noise at the amplifier !!

A simple solution would be to put some power diodes in series with the power supply. Each one would drop the voltage by a volt or so and hence bring the voltage seen by the A07 to an acceptable and safe level. BUT as said earlier be aware that there might be higher voltages present that would still kill the A07 !!

https://www.reddit.com/r/ShopCanada/comments/zeusix
My choice is now pretty settled.. will be a 36V DC-DC converter cause as this guy tested ... the 07 give more power with a 36V input then with a 48V.
For what i understood .. the 3255 dissipate too much heat at 48V and shutdown itself.

 

[krck]

Hi all,
I have a Aiyima A07 with a somewhat noisy toggle switch.
The switch induces a crackling noise into only one channel when switching the amp on. Sometimes the noise stays, a little quieter, sometimes it is not there.
If the switch produces noise, I can get rid of it be twisting the lever (rotating it around its own axis).

Is there a way to get rid of this crackling noise, e.g be cleaning, repairing or even replacing the toggle switch?

 

[John4949]

Hello, today I started to replace some components of my Aiyima A07 Amp like "trungdtmc". I just have a slight problem with placing the "coilcraft OEM inductor 10uH", they are just a bit too wide by 2 mm and therefore do not fit in the board. I thought of another solution therefore to move the "coilcraft OEM inductor 10uH" outside the Aiyima amplifier, for the moment simply to test the upgrading of better components. However, is there a risk for the amp to do this??? Deporting the inductors still adds about 10 cm of cable between the printed circuit and the terminals of the inductors, will this modify the value of the inductors?? Is there a polarity to respect for the inductors??? Well, I know that's a lot of questions, I prefer to be reassured by people who know about it. I wish you a good weekend. See you. Thanks.

 

[Roland68]

Hello, today I started to replace some components of my Aiyima A07 Amp like "trungdtmc". I just have a slight problem with placing the "coilcraft OEM inductor 10uH", they are just a bit too wide by 2 mm and therefore do not fit in the board. I thought of another solution therefore to move the "coilcraft OEM inductor 10uH" outside the Aiyima amplifier, for the moment simply to test the upgrading of better components. However, is there a risk for the amp to do this??? Deporting the inductors still adds about 10 cm of cable between the printed circuit and the terminals of the inductors, will this modify the value of the inductors?? Is there a polarity to respect for the inductors??? Well, I know that's a lot of questions, I prefer to be reassured by people who know about it. I wish you a good weekend. See you. Thanks.

If they have a polarity, it says so in the data sheet, with the design there is probably no polarity. Long cables for the inductors are not such a good idea, they should be placed as close to the IC as possible.
You could go another way and get rid of the problematic and undersized case.
Place the two outer inductors and the capacitors on the bottom. Find a case or a way to lay the A07 upright on its side. Better heat dissipation for the heat sink (chimney effect), larger heat sink possible, more space for better components.

 

[John4949]

Yes, however on the C.I. of the Aiyima amp you can see the different inscriptions between the right and left channel, one has the waves down and the other has the waves up. Alright, what's going on??

 

[Roland68]

Yes, however on the C.I. of the Aiyima amp you can see the different inscriptions between the right and left channel, one has the waves down and the other has the waves up. Alright, what's going on??

If inductors have a polarity, then they are always installed from input to output. For the inductors you bought, so Pin1 input, Pin2 output.
With the A07 board, the connection pointing towards the middle of the board (the inner one above the arc) is always the input. The exit is the one on the outside.

 

[John4949]

Thank you Roland68 for all these details, what a good idea to solder components from below, I hadn't thought of that. Besides, I just noticed that only two inductors were soldered in the right direction of polarity, I'm going to unsolder and reverse the other two so that all 4 inductors are ok. In fact all this is logical, there must be a sense of polarity because the lines soldered below the IC lead to the chip, i.e. the direction: TPA3255 chip towards the inductors and then inductors output towards speaker cable terminal. Luckily I didn't turn it on.... At worst it might have worked anyway..... Thanks for your help Roland68, I'll post some more pics when I'm done with the mods. I am also waiting for other Op-amp to test: "TLE2142CP" and also "OPA1656IDR" At the moment I put "OPA1612A", it's better than "LM4562NA".

 

[John4949]

Well, I'm happy because the sound is even more pleasant now, it will have been useful to replace all these components. I saw a video on Youtube of "trungdtmc" and therefore changed like him: nichicon FW 10uf 50v x9 --- wima mks4 1uf 100v x4 --- coilcraft OEM inductor 10uH x4 --- I still have the two capacitors of 50V 1200uF to be replaced with nichicon 1000UF 63V FW series but I haven't received them yet. By the way, the power supply used is a MEAN WELL LRS-350-36 Switching Power Supply Module SMPS 36V 9.7A, no background noise, no hiss, and the whole thing does not heat up at all. Long hours of listening to music are coming..... I also have a very good Dual AK4499 DAC with SparkosLabs SS2590 PRO AOP, so a very clean audio signal to enter the Aiyima A07. Goodbye. Next step: put the whole thing in a nice diy box (wood / metal).

 

[Scrufboy]

nichicon FW 10uf 50v x9 --- wima mks4 1uf 100v x4 --- coilcraft OEM inductor 10uH x4 --- I still have the two capacitors of 50V 1200uF to be replaced with nichicon 1000UF 63V FW

Where are you sourcing these parts?

 

[John4949]

aliexpress.com

 

[John4949]

 

[Scrufboy]

Yup... No prob... Except last time I ordered a set of cables, I got a dozen hello kitty pencil sets... Thanks... How do you know if they are real or not?

aliexpress.com