Ah, okay, that means, it's most likely a measuring issue, not a power supply issue. Thanks for clearing that up.
Hello everyone. This is the second time I have ordered 2 TDA8932BT and even after contacting the ebayer beforehand and asking him to confirm me that they were both the BT version, again I had problems: one is a TDA8932T and another one is a TDA8932BT/NP. Frankly, I am now asking myself who sells those BT versions? Now I'll have to wait two months again even if I'm willing to make another order.
I noticed that most sellers are shipping out only the T version.
The last boards I've ordered were these: eBay, these were the BT versions, that was back in feb. though.
That's included in the BT IC, you most likely can't change this behaviour at all. You could cut the BT-amp connection or the amp-speaker connection to mute that as a workaround. I know, that's not very satisfactory but at least some way to still use it.
@ICG: I did a brief listening and it doesn't sound that bad. Of course, the TDA8932T mono are better, its sound is clearer and richer (the instruments' sound is more detailed). The pros of the bluetooth version is that even while using it at a high volume, there aren't any problems of distortion (unlike the T version without it) but I think that at this point just for the bluetooth function and these perks it isn't worth the pain to bear that awful voice everytime.
Maybe, the last thing I'd like to have is a good power input for those boards. I'm waiting to build a good power supply with the help of someone here.
Maybe, the last thing I'd like to have is a good power input for those boards. I'm waiting to build a good power supply with the help of someone here.
It is very angry.
In your link, if the product matches the photo, you've used the amplifiers that I enjoy.
It is possible for the supply current, the voltage or the load to make it rebel.
As a totally off guess, the regulators in your power supply might not be up for handling a pair of lovely sounding, albeit incredibly inefficient, class d amplifiers.
Seems like either the current provisions have fallen short or the load is too close to a dead short. Some particular in-between means could provide a more enjoyable result.
It does as you describe (had one not bridged it at the tweeters).
This advance has caused two dreadfully laborious problems for me!
Well, I never thought I'd see the day; however, it arrived impolitely, without calling/texting ahead. Seems even worse unannounced, like an inconveniently soaked wild animal in my lap, with no notice beforehand, whatsoever. And, it has the urge to bite.
When suddenly having to go without an amplifier lack, then I have the new problems of arranging (probably manufacturing) the goodly source and speaker.
I have a few ideas, but I'm not thoroughly prepared to instantly produce the goodly source and speaker.
I actually hadn't checked thoroughly, within this decade. On a new and sudden reconnoiter, initially I found out that the speaker people have made no progress; and, that's wonderfully convenient for me, because I'll be able to produce relevant speakers without having to reinvent even one wheel. However, the source people have made some progress; so, I'll be tuning in to get some briefings on how to, most directly, manufacture the goodly source.
It isn't so convenient for the speaker either, because there's that matter of sawdust in my hair and drawers, and really effective glue on my fingers. Oi!!!
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Hacked the Philips server 
Found this (confidential):
PHILIPS TDA8932
There is a solution for the gain problem BTW.
Just trying out 2 Sanwu mono boards, no diodes used for PSU dividing.
High hum and medium hiss level problem.
Found this (confidential):
PHILIPS TDA8932
There is a solution for the gain problem BTW.
Just trying out 2 Sanwu mono boards, no diodes used for PSU dividing.
High hum and medium hiss level problem.
Installed the 4k7 input with 12k across for reducing the gain, added the divider diodes (Schottky 8A 60V) with Nichicon ES 1000/25 caps after.
Still HUMMING with 93dB fullrange.
With same case and PSU (Meanwell 17V) and tube pre I had no hum or hiss with the TPA3116.
Any suggestions? Thanks.
Still HUMMING with 93dB fullrange.
With same case and PSU (Meanwell 17V) and tube pre I had no hum or hiss with the TPA3116.
Any suggestions? Thanks.
Some listening impressions with 3 D-Amps, TA2020, TPA3116 & TDA8932
Categories and the winners:
Highs: TPA3116 - less distortion
Mids: TPA3116 - much more detail
Bass: TA2020 - fruity, solid, deep driving bass not too fat. TDA8932 has more bass but it is slower and muddier. TPA3116 is fastest here but lacking some grip and drive.
Space/Stage/3D: TPA3116 - TDA8932 sounds like a Jazz Club all the time, more intimate but missing awful much detail. TDA8932 cant hold a candle vs TPA3116 in this category.
Micro Dynamics: TPA3116 - so much better
Macro Dynamics: TDA8932 - outstanding, best macro dynamics so far ever from a D-Amp!
Rhythm & Flow: TA2020 & TPA3116 - a matter of taste maybe, TDA8932 fails here, mechanical rhythm means no fun! The TDA7492/98 was much better here
I dont see any reason for me to change over from TPA to TDA
I will do more testing with the TDA7492/98.
Conclusion in reference to the TDA8932: Case closed!
Categories and the winners:
Highs: TPA3116 - less distortion
Mids: TPA3116 - much more detail
Bass: TA2020 - fruity, solid, deep driving bass not too fat. TDA8932 has more bass but it is slower and muddier. TPA3116 is fastest here but lacking some grip and drive.
Space/Stage/3D: TPA3116 - TDA8932 sounds like a Jazz Club all the time, more intimate but missing awful much detail. TDA8932 cant hold a candle vs TPA3116 in this category.
Micro Dynamics: TPA3116 - so much better
Macro Dynamics: TDA8932 - outstanding, best macro dynamics so far ever from a D-Amp!
Rhythm & Flow: TA2020 & TPA3116 - a matter of taste maybe, TDA8932 fails here, mechanical rhythm means no fun! The TDA7492/98 was much better here
I dont see any reason for me to change over from TPA to TDA
I will do more testing with the TDA7492/98.
Conclusion in reference to the TDA8932: Case closed!
V+ power pin decoupling. Okay. What sort of cap (type and capacitance) did you change it to? Was the stock cap removed or just added to (bypassed) with an additional cap? Also, did you change that 10 ohm resistor?
I went through a whole range of options, starting out with 10uF ceramic I think and then up to a few thousand uF in low-ESR caps. Eventually I settled on a discrete regulator and it turns out you can get away with a lower voltage than the main supply when running (as I was doing) at 24V and above for the output stage.
I did change the 10R resistor yes, reduced it to 3.3ohm when I went to electrolytics, then also tried an inductor instead of it. The inductor sounded cleaner than the resistor.
I did change the 10R resistor yes, reduced it to 3.3ohm when I went to electrolytics, then also tried an inductor instead of it. The inductor sounded cleaner than the resistor.
Oh, I get it.
VDDP1 = right channel large signal power
VDDP2 = left channel large signal power
VDDA = small signal power
Variance permitted by resistor Rvdda makes selecting the perfect cap impossible. What value of inductor to replace Rvdda and what value of cap to replace Cvdda?
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I am planning on running 4 Peerless SLS-12 woofers (90 dB/W, 8 Ohms) with these amps with 20-350 Hz frequensies. One amplifier per speaker with the amps mounted on old computer CPU coolers. Power would be supplied to all by a 24V 10A PSU.
Does this sound like a solid plan? Should I run the amplifiers in master-slave mode with one being the master and others slaves? Any other tips and tricks you would recommend for this application?
Does this sound like a solid plan? Should I run the amplifiers in master-slave mode with one being the master and others slaves? Any other tips and tricks you would recommend for this application?
My TDA8932-
https://goo.gl/photos/NeTGW3yKBvwEHDzG8
I wanted to create a TPA32xx board, but wasn't sure I could deal with the pin spacing on the ssop parts, so found the TDA8932 which is in a size I can deal with, and used the datasheet as my guide.
The board has the taller parts 'mirrored' so 2 can be 'sandwiched' together with the parts facing inward. I'm not sure why I did that, but I did. There was only one mistake (that I know of)- I used a Wima cap footprint on all the 0.1in spaced caps but I didn't realize the hole size is too small for the normal/cheap caps, which means I had to use all Wima caps. Which also meant my 'sandwich' was not as compact as it could be since I didn't plan on the taller caps in several locations.
So, I assembled what I had and hooked up the pair to my speakers (Fostex Fe167 in a decent sized MLTL(?) box (http://www.mtcnet.net/~henryvm/fe167e/P6230517.jpg). Since I wasn't thinking too clearly, I just hooked everything up, set the power supply to 12v, and turned them on. My expectations were low, but I had music playing a few seconds after I turned on the power- very nice surprise.
I made a few voltage checks, checked the mute, tested my diagnostic led by undervolting, then turned up the power supply to 19v (what I expect to run at with laptop power supply). Played music for about 30 minutes (loudly)- sounds pretty good to me. I checked the heat of the tda's, they were quite warm but could still touch them. I decided to see what 24v would sound like, so cranked up the power supply. I discovered my power supply current limit was set too high- how? When one one of the amps started to smoke and the power supply went crazy. I destroyed my first tda, but had a few spares so I replaced it. Works ok again, but I keep voltage below 19v until I figure out what may have happened.
https://goo.gl/photos/NeTGW3yKBvwEHDzG8
I wanted to create a TPA32xx board, but wasn't sure I could deal with the pin spacing on the ssop parts, so found the TDA8932 which is in a size I can deal with, and used the datasheet as my guide.
The board has the taller parts 'mirrored' so 2 can be 'sandwiched' together with the parts facing inward. I'm not sure why I did that, but I did. There was only one mistake (that I know of)- I used a Wima cap footprint on all the 0.1in spaced caps but I didn't realize the hole size is too small for the normal/cheap caps, which means I had to use all Wima caps. Which also meant my 'sandwich' was not as compact as it could be since I didn't plan on the taller caps in several locations.
So, I assembled what I had and hooked up the pair to my speakers (Fostex Fe167 in a decent sized MLTL(?) box (http://www.mtcnet.net/~henryvm/fe167e/P6230517.jpg). Since I wasn't thinking too clearly, I just hooked everything up, set the power supply to 12v, and turned them on. My expectations were low, but I had music playing a few seconds after I turned on the power- very nice surprise.
I made a few voltage checks, checked the mute, tested my diagnostic led by undervolting, then turned up the power supply to 19v (what I expect to run at with laptop power supply). Played music for about 30 minutes (loudly)- sounds pretty good to me. I checked the heat of the tda's, they were quite warm but could still touch them. I decided to see what 24v would sound like, so cranked up the power supply. I discovered my power supply current limit was set too high- how? When one one of the amps started to smoke and the power supply went crazy. I destroyed my first tda, but had a few spares so I replaced it. Works ok again, but I keep voltage below 19v until I figure out what may have happened.
Attachments
My PSU is adjustable on the 22-26V range, I've adjusted it with multimeter to be exact 24V (without load).
I forgot a 100nf cap on the board that had the tda smoke/internally short out- a bypass cap for dref. I only noticed the missing cap after trying to figure out how much space I had to fit some kind of heatsink (and its now obvious when looking at my pictures).
I'll assume the internal regulator did not like the missing bypass cap. I think if it was heat related, the tda would go into one if its many error modes of self-preservation.
I tested the pair of boards for several hours, running at about max volume and at 19V (I have gain reduction per datasheet to about 31db). The tda's get quite warm but I can still touch them without losing fingerprints. I would still like to jbweld something to the chips, though. I wish I had paid more attention to the thermal sections of the datasheet, but I mostly skipped them because of the 'no heat sink required' in the first part of the datasheet. It appears the four corner ground pins are designed to move a lot of the heat, so maybe some 'end plates' soldered on the end pins would help also.
I don't have a lot to compare with, but these amps sound very nice and with efficient speakers can get quite loud (more is always better it seems, but its probably a good thing to have hardware that keeps one from listening at levels louder than necessary).
I would also add that NXP does a good job with their datasheets (their microcontroller datasheets are good, too). I followed the datasheet example pretty closely and ended up with a nice amp.