Hi,
I am planning to replace the Capacitors around the op-amps with Silmic 2 (Thanks to lwj5 for advice) and i installed OPA2228 instead of the fake NE5532. Apparently my board seems to burn the OPA1656 (or just a bad batch) but works fine with OPA2228.
https://www.diyaudio.com/forums/attachment.php
For inductors do you recommend replacing them with 22uH for 8-Ohm speakers or leaving the current one (10uH) should be fine.
I was planning on using this ones SER1512-223MED Coilcraft | Mouser Slovakia and also replacing the 1uF capacitors with Wima MKP 0.47uf.
Does it worth?
I am planning to replace the Capacitors around the op-amps with Silmic 2 (Thanks to lwj5 for advice) and i installed OPA2228 instead of the fake NE5532. Apparently my board seems to burn the OPA1656 (or just a bad batch) but works fine with OPA2228.
https://www.diyaudio.com/forums/attachment.php
For inductors do you recommend replacing them with 22uH for 8-Ohm speakers or leaving the current one (10uH) should be fine.
I was planning on using this ones SER1512-223MED Coilcraft | Mouser Slovakia and also replacing the 1uF capacitors with Wima MKP 0.47uf.
Does it worth?
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Hello,
i'am running my 3e audio 3255 amp. What is it for 12V input? I experienced that if not used amp sounds anyway.
Thanks in advance
i'am running my 3e audio 3255 amp. What is it for 12V input? I experienced that if not used amp sounds anyway.
Thanks in advance
The 12v is an output, not an input. It allows a feed to be taken to power a DAC or similar, to a max of 200mA.
As my PCBs arrived yesterday I could not resist populating the first prototype. It is up and working at a first glance. 🙂
The controller works as aspected but some programming work remains. In between I had a hard time with my AVR toolchain and CodeBlocks that only work on an old LMDE3 Linux distro but miserably fail with current LMDE4.😱
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I am planning to buy this amplifier.Hi,
I am planning to replace the Capacitors around the op-amps with Silmic 2 (Thanks to lwj5 for advice) and i installed OPA2228 instead of the fake NE5532. Apparently my board seems to burn the OPA1656 (or just a bad batch) but works fine with OPA2228.
https://www.diyaudio.com/forums/attachment.php
For inductors do you recommend replacing them with 22uH for 8-Ohm speakers or leaving the current one (10uH) should be fine.
I was planning on using this ones SER1512-223MED Coilcraft | Mouser Slovakia and also replacing the 1uF capacitors with Wima MKP 0.47uf.
Does it worth?
Does this product have an anti-pop circuit?
I bought a model of this amplifier without BT, but when I turned the power on and off, pop noise was so bad that I couldn't use it.
The anti-pop circuit doesn't work either on this one but not that bad noise btw.
What i observed is that depending on the power-supply the pop-up noise can be reduced further.
If i was now to buy a new board with all the test i've done so far I would rather prefer to try to this board available on ebay instead of the amp i brought.
Maybe even i will order it in addition.
I have seen users posting photos with this model so we can ask them to share their experience.
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The anti-pop circuit doesn't work either on this one but not that bad noise btw.
What i observed is that depending on the power-supply the pop-up noise can be reduced further.
If i was now to buy a new board with all the test i've done so far I would rather prefer to try to this board available on ebay instead of the amp i brought.
Maybe even i will order it in addition.
I have seen users posting photos with this model so we can ask them to share their experience.
Danny (on this forum) has experience of this board !! The first time it was plugged in the 12volt regulator burnt out. Manufacturer only used 40volt regulator components on a 48 volt board. Also inductor values in the Power Supply appear to be wrong and hence overloading the regulator !
So if you buy this board expect to do some reworking before you attach to Power !!
Danny has it working now after replacing some components so can probably tell us what it sounds like.
On the Aiyima A09 TPA3255 unit, I have this same unit without the Anti-Pop circuit and yes it makes a big noise when turning on and off with the front switch ! If you turn the power off and on to the power supply there is almost no noise. The latest release of the PCB In this model now appears to include the Anti-Pop circuit and is identical to the Tilear Aiyima A04 TPA3251 model.
Hi and thank you. So apparently there is no board that doesn't require a bit of rework 🙂.
Is there anyone that replaced the inductors on Aiyima TPA3255 with some fitting alternatives and what was the selected models. I read all the 220 pages but couldn't find much for 8-Ohm cases except for the values.
According to the posts for 8-Ohm speaker i should use 15uH and according to the Ti calculator 22uH with different caps (0.47uF or respectively 0.68uF) assuming that i chose the right filter type.
Both options seems to work fine but i was wondering if anyone can share their experience will be much appreciated.
https://www.diyaudio.com/forums/attachment.php?attachmentid=850748&stc=1&d=1591535550
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I have 2 samples of these as well. They may be slightly better than the ferrocore at twice the price. Later on I will do a comparison.
I have both the Aiyima TPA3255 and TPA3251 based amplifiers.
I believe the standard inductors are 12.5uH and the output Caps are 1uF.
I drive some KEF UniQ speakers that have a nominal 6 Ohm impedance. Seems to work OK with these but then I have not tried any output Filter modifications - There is so little space to play with. That said there is one guy who created a new piggyback board to replace the whole of the output filter and Power Supply Caps side of the TPA3255 board. There are pictures earlier in this thread.
Thank you for providing the information. So it will be helpful.
sorry. I participated in the diyAudio forum for the first time. I still don't understand how to write, but thank you.
sorry. I participated in the diyAudio forum for the first time. I still don't understand how to write, but thank you.
I changed the values of the inductors to match my speaker impedance as I know I won't be using any speakers with lower impedance in the future. You could change those inductors for a higher one if you are sure about that too. Using any speakers with lower impedance than that will trim part of the audible range which is something you do not want.
Does your speaker have any impedance curve chart? You could see what the impedance is above 1kHz if it's above 8ohms for the entire range then you are good to go. Make sure that you get inductors with a sufficiently high saturation current.
I realized B32671P4105K000 TDK Electronics Inc. | Kondensatoren | DigiKey as recommended by doctormord fits well with the AIYIMA without mods as it has 10mm lead spacing. I'm thinking of swapping to this and trimming my overlay board down to only hold the new inductors instead of inductors + caps and that should reduce EMI. I'm awaiting the parts and I will test the sound difference before doing this permanently.
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Hi James,
Take a look on previous pages, I reviewed the new version I received : the board is working fine now. Seems regulator has been updated like already discussed ) Take a look on that full review 🙂
Hi, it seems that TDK PP 0.47uF and 0.68uF are in stock B32671P4684K000 EPCOS / TDK | Mouser Slovakia . I believe is exactly what goes with the inductors 15uH and 22uH for 8 Ohm with a cut-off at 40Khz, so i will add them to my shopping list 🙂. I assume that 1uF would be used in the case you have a lower cut-off frequency based on the simulator.
Hi James,
Take a look on previous pages, I reviewed the new version I received : the board is working fine now. Seems regulator has been updated like already discussed ) Take a look on that full review 🙂
I am interested in this board as my next project. I will read your previous comments around it. Thank you.