The transformers I use on my amp aren't particularly heavy ones - because I'm a curious type I just weighed one : 17g. I don't have a plan C - there's no alternative to trafos that I've so far found. Not to say that there can't be one though, just I'm not aware of it.
Maybe this is related?: I'd like to get out of buying woofer and subwoofer crossovers (huge inductor and cap board). But active eq doesn't do bass quality, so I end up buying the inductors anyway. 🙂
You can try line level passive crossovers - the inductors will be much much smaller as their DCR becomes much less important. Gapped ferrite cores (say RM10 size) are your friend 😀
B65813J0400A087 EPCOS / TDK | Mouser
B65813J0400A087 EPCOS / TDK | Mouser
Brought two TDA8932 boards from china for total 3$. They are so tiny. without any issue they are playing music. I am surprised with those. One day I will try to build my self with Gerber available in this thread. As per abraxalito suggestion I looked to add capacitor but boards are so tiny not possible. But am happy with them.
1pcs Digital power amplifier board module 35w mono amplifier module High power TDA8932 low power consumption-in Integrated Circuits from Electronic Components & Supplies on AliExpress
1pcs Digital power amplifier board module 35w mono amplifier module High power TDA8932 low power consumption-in Integrated Circuits from Electronic Components & Supplies on AliExpress
I have many of these boards and they play surprisingly well. The TDA8932 is a great chip. The board is very cheap and the components used pretty basic. Really doing a lot of modification on such a sample board is hardly worth the effort. Give it 2200uF at the power input terminals with the capacitor located at the rear of the board and leave it like that.
Forgive the basic nature of the question, but what is the best/most appropriate type of capacitor to use in this case?
Hi I tried 4700uF 35V capacitors old ones but when I connect no sound coming.I don't know these capcitors dead or not. I am checked voltage between capacitors leds it is dropping to 2 volts. I am using dell laptop charger. So removed caps and working fine.
Is the board went into protective mode ?. or laptop charger went into protective mode ?.
Any help.
Any help.
Has anyone tried these stereo boards? https://www.aliexpress.com/item/4000554917679.html
In the past I've only seen the bluetooth boards in stereo for the TDA8932 (with the unbearable voice prompts).
In the past I've only seen the bluetooth boards in stereo for the TDA8932 (with the unbearable voice prompts).
I would love to start seeing the clipping characteristics of all these "wonder chips" that are ALL touted as "the best sounding" in the Class D realm. To my knowledge, the ONLY Class D chip that produced a soft clipping characteristic - similar to a vacuum tube or single-ended FET - is the Tripath series - from way back when. (Tripath Class"T" is just a marketing trademark.)
Can somebody who has a TDA 8932 amp and test equipment please push the amp into light clipping and show us what the waveform looks like at the onset?
Can somebody who has a TDA 8932 amp and test equipment please push the amp into light clipping and show us what the waveform looks like at the onset?
Why do you want to see the clipping output signal?
What information will give it to you?
If I find the board at home, I will try to make the measurements, but on power resistors as load, not real speakers!
What information will give it to you?
If I find the board at home, I will try to make the measurements, but on power resistors as load, not real speakers!
Whereas I agree with you that Tripath chips have a very pleasant sound, perhaps due to intentional clipping management, I don't think anybody has stated that the TDA8932 has a similar clipping feature. The TD8932 indeed sounds very pleasant as it is.
The TDA8932 chip seems to be intended for low cost purposes but is anyway perhaps the best sounding class D chip from Philips/NXP.
An issue is that for DIY purposes, the TDA8932 seems only used on small cheap boards that in no way let the TDA8932 perform to its potential. "Matt" on this forum made a serious TDA8932 board and that one should sound really fantastic.
Clipping performance is by and large determined by the nature of the feedback loop. In particular if it contains any integrator sections and how they enter and recover from saturation. The 8932 appears to incorporate no means for external feedback and as such would be expected to hard limit but have excellent recovery characteristics.
Anyone know a new source for this stereo version of the board? I should have bought it when it was available. All I see now are mono or bluetooth board versions on Ali / eBay. This quarantine has me starting even more projects.
Mono transformer isolated amp board
After many years modding and developing amps using TDA8932 I at last made a PCB for a mono implementation of this delightful IC. For the sake of simplicity its using an LC filter on the critical-for-SQ rail on pin8. When I listened to this it was OK-sounding but the bass wasn't quite as dynamic as it could have been and massed voices sometimes sounded grungy.
I put my USB soundcard on the pin8 rail and recorded what was there. Audacity showed nice rejection of noise above 1kHz or so but lots of load-induced noise below that. So I pulled out the LC filter and installed an LM317 regulator instead. A very nice improvement in dynamics resulted along with some improvement in clarify of voices. The USB ADC confirmed a cleaner pin8 supply. So then I figured - what about powering the main rail (pins 20,29) with a regulator too? An LM317 can deliver up to 2.2A provided the voltage drop isn't too high so I figured with my 8ohm speakers I'd be good if the rail was only 16V. The result was a significant lift in bass tightness or tunefulness. So the PCB's going to be modded for regulators on both chip supplies in the next rev. Stay tuned!
I'm also planning to extend the working voltage higher a bit by using a slightly higher rated regulator - LD1085 (3A) so the supply rail can in theory be pushed near to 24V.
After many years modding and developing amps using TDA8932 I at last made a PCB for a mono implementation of this delightful IC. For the sake of simplicity its using an LC filter on the critical-for-SQ rail on pin8. When I listened to this it was OK-sounding but the bass wasn't quite as dynamic as it could have been and massed voices sometimes sounded grungy.
I put my USB soundcard on the pin8 rail and recorded what was there. Audacity showed nice rejection of noise above 1kHz or so but lots of load-induced noise below that. So I pulled out the LC filter and installed an LM317 regulator instead. A very nice improvement in dynamics resulted along with some improvement in clarify of voices. The USB ADC confirmed a cleaner pin8 supply. So then I figured - what about powering the main rail (pins 20,29) with a regulator too? An LM317 can deliver up to 2.2A provided the voltage drop isn't too high so I figured with my 8ohm speakers I'd be good if the rail was only 16V. The result was a significant lift in bass tightness or tunefulness. So the PCB's going to be modded for regulators on both chip supplies in the next rev. Stay tuned!
I'm also planning to extend the working voltage higher a bit by using a slightly higher rated regulator - LD1085 (3A) so the supply rail can in theory be pushed near to 24V.
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Great stuff....i might be interested in a couple of boards if you're producing a batch and they are not too small on the SMD front!
Thanks - I'll be putting the gerbers up, normally cheapest to order boards yourself from someone like JLCPCB as their shipping rates are unbelievably low. Most of the SMD is 0805, nothing smaller than that. The transformer is a custom wind on EP17 10k core, you can wind it yourself or alternatively buy from me.
The 2x15w stereo version of the board disappeared shortly after my initial post. It seems to be uncommon, but one just resurfaced if anyone is interested.
AIYIMA TDA8932 Sound Amplifier Board 15Wx2 Dual Channel Class D Digital Power Amplifier Stereo Audio Amp With Mute Control DIY|Amplifier| - AliExpress
AIYIMA TDA8932 Sound Amplifier Board 15Wx2 Dual Channel Class D Digital Power Amplifier Stereo Audio Amp With Mute Control DIY|Amplifier| - AliExpress