I have the same subwoofer amp, but with different capacicitors.
All elec caps look different on mine.
Is that the stock form of the amp?
I think some further refinement could remove the very last tiny noise. But bearing in mind I have 97dB mids with compression drivers (108dB) and a ported 60L cab with 12" JBL subwoofer, that is not a concern.
120mS could be a little longer if you need absolute silence. In this case, the improvement is so much that it is not worth it.
120mS could be a little longer if you need absolute silence. In this case, the improvement is so much that it is not worth it.
Re-purposed 2*12 sealed guitar cab with some extra bracing. Ebay second hand woofer. Very cheap 
The satellites are also old charity shop speakers with new drivers. Theoretically the sub driver is the weak link if I really wound the volume up. The second 12" speaker has been replaced with a plywood disc with the double flared port in it. Also the 1/4" jack sockets replaced with a (sealed) speakon connector plate.
The satellites are also old charity shop speakers with new drivers. Theoretically the sub driver is the weak link if I really wound the volume up. The second 12" speaker has been replaced with a plywood disc with the double flared port in it. Also the 1/4" jack sockets replaced with a (sealed) speakon connector plate.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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Well, I got my board today, it has a 15V regulator and there is almost no static noise.
But the Voltage Regulator has no label on it, therefore I'm a bit afraid to run the amp at 50V.
Theres only a little "V" marking on it, so is this just a cheap china lm2575-15 copy?
But the Voltage Regulator has no label on it, therefore I'm a bit afraid to run the amp at 50V.
Theres only a little "V" marking on it, so is this just a cheap china lm2575-15 copy?
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Well, I got my board today, it has a 15V regulator and there is almost no static noise.
But the Voltage Regulator has no label on it, therefore I'm a bit afraid to run the amp at 50V.
Theres only a little "V" marking on it, so is this just a cheap china lm2575-15 copy?
Almost definitely the cheaper lower input voltage device.
It's easy to swap. Sometimes better to cut the pins rather than trying solder sucker or braid. The PCB lands aren't very substantial so destroying the device to get it off is preferred to ripping or melting the tracks off.
The LM is a bit more robust regarding overvoltage/overshoot (63V vs. 60V) from the datasheet specifications. The TL type is the same a the LM spec-wise but presumably manufactured in a more modern/optimized process which make it cheaper.
LMXX 1999
TLXX 2006
If you can effort the $0.9+, go for the LM, otherwise the TL.
(If they do the same manufacturing process for both devices, the LM type would be the better "bin" then - tested at the preaging/burnin process on wafer-level selection)
LMXX 1999
TLXX 2006
If you can effort the $0.9+, go for the LM, otherwise the TL.
(If they do the same manufacturing process for both devices, the LM type would be the better "bin" then - tested at the preaging/burnin process on wafer-level selection)
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Next thing I want to do is changing the gain of the opamp to 20dB, so I get a overall gain of 43dB and can push the amp to its limit with smartphones(0.25V Input).
So looking at page 23 of the EVM Datasheet, I only need to change R62+R66 to 44kOhm and C77+C78 to 35pF, right?
http://www.ti.com/lit/ug/slau287a/slau287a.pdf
So looking at page 23 of the EVM Datasheet, I only need to change R62+R66 to 44kOhm and C77+C78 to 35pF, right?
http://www.ti.com/lit/ug/slau287a/slau287a.pdf
Actual versions from manufacturer has this problem?
Some info. I dont know about old releases and fixes of this bug in past time, but actual PBTL 600W blue ver. of tas5630 amp from yuangjing manufacturer, has a "true" LM2575s-15 onboard.
Today order a 300+300 red version, will see on it, in other, no big problem to change this chip.
Some info. I dont know about old releases and fixes of this bug in past time, but actual PBTL 600W blue ver. of tas5630 amp from yuangjing manufacturer, has a "true" LM2575s-15 onboard.
Today order a 300+300 red version, will see on it, in other, no big problem to change this chip.
I did some investigations on the turn on/off pops, they are depending on the Audio Source Impedance:
-Low Impedance Source(Phone, 70Ohm), no signifcant pops
-10k:No harmfully pops, ~2V DC maybe
-No Source Connected: huge ~10V DC Pop.
So, I think I should just use a 10k Volume Control Potentiometer to get rid of the pops.
-Low Impedance Source(Phone, 70Ohm), no signifcant pops
-10k:No harmfully pops, ~2V DC maybe
-No Source Connected: huge ~10V DC Pop.
So, I think I should just use a 10k Volume Control Potentiometer to get rid of the pops.
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I had no real troubles with just the satellites and one board. High efficiency drivers, low/medium volume setting and sealed cabs was OK. Adding another single channel subwoofer card with a 12" sub in a sealed 20L box was OK, but you could see the driver moving on powerup/down.
12" driver in much larger 60L ported box and it was going to break! It wasn't so much the click, but the large amount of very low frequency produced. With no 'acoustic suspension' the cone simply moved a very long way
An earlier poster had determined it was the op amp supplies drifting on powerdown that caused this trouble, not the amp chip itself.
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