Figured they weren't really all that good.
I'll go with a bridged version then as that will do exactly what I want.
I'll go with a bridged version then as that will do exactly what I want.
Not sure I understand what just happened to one of the amp boards.
All I did was disconnect the 10k pot leaving only the 50k pot in circuit and used the switch on the back of the 10k pot as the power switch and one amp chip is now causing the power supply to hit the 1A current limit I had set.
Thankfully I have another board, but nothing I did should have caused that chip to fail.
Was it:
1. A random failure.
2. Is the way I'm using the amps bridged with no speaker coupling caps causing the problem.
3. Did that one chip get compromised when the other chip failed and would have failed today anyways.
I'm tempted to ditch the 2050 boards and find some other small amp board, however the amp would need to be single supply which means the output has to either be bridged or use an output coupling cap. I don't want an output coupling cap as I'd need a rather large value to eliminate phase shift down to 40Hz and I haven't had much luck with bridged. Running a dual supply is not possible as I would need to at minimum run a third power wire and add a jack to the chassis.
What would be the best option?
Also are there any small boards like what I need that are relatively inexpensive?
I could still restore my Heathkit A9C amp and use it with the speaker, but am trying to stay away from that if at all possible as it doesn't fit the small footprint I desire.
All I did was disconnect the 10k pot leaving only the 50k pot in circuit and used the switch on the back of the 10k pot as the power switch and one amp chip is now causing the power supply to hit the 1A current limit I had set.
Thankfully I have another board, but nothing I did should have caused that chip to fail.
Was it:
1. A random failure.
2. Is the way I'm using the amps bridged with no speaker coupling caps causing the problem.
3. Did that one chip get compromised when the other chip failed and would have failed today anyways.
I'm tempted to ditch the 2050 boards and find some other small amp board, however the amp would need to be single supply which means the output has to either be bridged or use an output coupling cap. I don't want an output coupling cap as I'd need a rather large value to eliminate phase shift down to 40Hz and I haven't had much luck with bridged. Running a dual supply is not possible as I would need to at minimum run a third power wire and add a jack to the chassis.
What would be the best option?
Also are there any small boards like what I need that are relatively inexpensive?
I could still restore my Heathkit A9C amp and use it with the speaker, but am trying to stay away from that if at all possible as it doesn't fit the small footprint I desire.
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While I like that option, the amp is being used in a shielded room and a class D amp would cause interference with the unit I test at work.
The amp would need to be more of a traditional amplifier.
The amp would need to be more of a traditional amplifier.
What the heck is it driving that you don’t want a coupling cap? Small lowish power speakers don’t have much 20 Hz and under output anyway. 6800 uF works just fine listening to music.
It's just that I don't want a capacitor in the output as the larger the cap is the louder the turn on pop is.
6800uF with a 16 ohm speaker has minimal phase shift at 50Hz though.
6800uF with a 16 ohm speaker has minimal phase shift at 50Hz though.
If designed well the amp will not produce any on/off pop.
https://www.akitika.com/documents/AssemblyManualGT102-Z4VersionRev1p06.pdf
https://www.akitika.com/documents/AssemblyManualGT102-Z4VersionRev1p06.pdf
Agreed.
In the past with a couple amplifiers where I used a relatively large output coupling cap I used a DPDT relay with a cap and resistor to delay its turn on with the NC contact connected to a 100 ohm resistor with the other end of the 100 ohm resistor grounded. That way the charge current of the caps went through the 100 ohm resistors and not the speakers.
In the past with a couple amplifiers where I used a relatively large output coupling cap I used a DPDT relay with a cap and resistor to delay its turn on with the NC contact connected to a 100 ohm resistor with the other end of the 100 ohm resistor grounded. That way the charge current of the caps went through the 100 ohm resistors and not the speakers.
It may be he is driving a mirror ball motor instead of a speaker, using the chip to amplify a control signal, or another type of non audio load.
I would simply use a VFD drive, or a higher powered chip / transistor amplifier, instead of a bridged chip amp for this purpose.
I would simply use a VFD drive, or a higher powered chip / transistor amplifier, instead of a bridged chip amp for this purpose.
Decided to lower the B+ to 30Vdc from 44Vdc as I doubt I'll need the extra wattage 44Vdc will get me.
Also I will need to use two 1N4960 zeners in series to drop 24Vdc for the fan which will run on 6Vdc. I had used a 1N4972 which is a 39V zener when the B+ was 44Vdc.
Also I will need to use two 1N4960 zeners in series to drop 24Vdc for the fan which will run on 6Vdc. I had used a 1N4972 which is a 39V zener when the B+ was 44Vdc.