I think you are referring to the (medium frequency) local supply rail decoupling.
Make sure you implement the high frequency local supply rail decoupling, as described in the chipamp datasheet.
Make sure you implement the high frequency local supply rail decoupling, as described in the chipamp datasheet.
I'm building another chipamp based on Audiosector boards.
Have already soldered 1.500 uF caps on the amp boards, and my intention was to use 10uF FCs on the rectifier board, however now I'm considering using 10.000uF Elna gold caps and snubber in the supply instead.
Should I then decrease the value of the caps near the chips, or will I be OK with those 1.500uF caps?
By the way this amp will include an X-10D tube buffer clone.
/Jan
Have already soldered 1.500 uF caps on the amp boards, and my intention was to use 10uF FCs on the rectifier board, however now I'm considering using 10.000uF Elna gold caps and snubber in the supply instead.
Should I then decrease the value of the caps near the chips, or will I be OK with those 1.500uF caps?
By the way this amp will include an X-10D tube buffer clone.
/Jan
You will be OK with 1500uF caps on amp board, but you can also use much smaller values, something like 100uF or so. That second option might be probably better, especially if you use more "exotic" caps.
OTOH, the stock configuration may be preferred too, so best is to compare all the options.
The PS board can hold large caps and snubber components.
OTOH, the stock configuration may be preferred too, so best is to compare all the options.
The PS board can hold large caps and snubber components.
Attachments
Thanks Peter,
Some years ago I made another with 10.000uF and snubber, and there I used 250uF at the chip. But I'll give it try with those 1.500uF FC + the large Elna caps.
Best Regards
Jan
Some years ago I made another with 10.000uF and snubber, and there I used 250uF at the chip. But I'll give it try with those 1.500uF FC + the large Elna caps.
Best Regards
Jan
QUAD ESL 57
Hello
Has anyone tried the Gainclone amp with QUAD ESL 57 electrostatic speakers? Thanks
Muimui
Hello
Has anyone tried the Gainclone amp with QUAD ESL 57 electrostatic speakers? Thanks
Muimui
Hello, I am back to gainclones
I recently builded an audiosector kit and one point by point, both around the LM3875 chip
I am using a tube buffer at the input and two 10k tocos pots
after an hour or so of music, pafff!!!
I have to run like crazy to decrease the vol pots, before my speakers get kaput
a big noise, woofers at maximum excursion, big panic!!
please help, what can I do? heeeeelpp!!
thank you!
I recently builded an audiosector kit and one point by point, both around the LM3875 chip
I am using a tube buffer at the input and two 10k tocos pots
after an hour or so of music, pafff!!!
I have to run like crazy to decrease the vol pots, before my speakers get kaput
a big noise, woofers at maximum excursion, big panic!!
please help, what can I do? heeeeelpp!!
thank you!
Post some pictures of your build. You had excessive DC output at the amp.
Hard to advice without any additional details.
Hard to advice without any additional details.
Hi Peter,
Excuse for the mess,,,
This is an experience, before to make my final version, whose photos I'll publish here,,,
So my speakers are slowly cooking,,,
I followed what I drawed, please see my draw
from pot :
1 goes to power ground between caps
2 goes to 220r (amp, in)
3 goes to power ground, on top of 680r - should this one go to pin 8, directly?
positive rca goes to 3 from rca to pot
Album photos GC LM3875-Tocos version - Casimages.com
Excuse for the mess,,,
This is an experience, before to make my final version, whose photos I'll publish here,,,
So my speakers are slowly cooking,,,
I followed what I drawed, please see my draw
from pot :
1 goes to power ground between caps
2 goes to 220r (amp, in)
3 goes to power ground, on top of 680r - should this one go to pin 8, directly?
positive rca goes to 3 from rca to pot
Album photos GC LM3875-Tocos version - Casimages.com
another experiment, but lm3886
I'll change the bridge, may be schottkys, IF it makes a difference - does it really?
Photo _DSC0638 de l'album LM3886 Premier - Casimages.com
final version (if final), will be two power banks of 64 caps each, per channel, each cap 47uF/50v silmics and z foils for 22k and 220 resistor
if I can avoid the 220r, I will
680r armtrans - is it worth here, or allen bradley?
I'll change the bridge, may be schottkys, IF it makes a difference - does it really?
Photo _DSC0638 de l'album LM3886 Premier - Casimages.com
final version (if final), will be two power banks of 64 caps each, per channel, each cap 47uF/50v silmics and z foils for 22k and 220 resistor
if I can avoid the 220r, I will
680r armtrans - is it worth here, or allen bradley?
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If both of the channels output DC then there is a good chance it is the power supply ground.
Disconnect the speakers and measure voltage at the PSU and output to ground. Could also be the pre, as you haven't used a capacitor at the input.
Disconnect the speakers and measure voltage at the PSU and output to ground. Could also be the pre, as you haven't used a capacitor at the input.
Hi Mark, I have capacitors in the tube buffer output stage, 6,8uF each
PSU, -31v,+31v,+62v
output to ground, 0, nada!
PSU, -31v,+31v,+62v
output to ground, 0, nada!
The wiring looks fine and if it played for an hour it seems like there was no error in you setup.
Can you check the DC output while playing music.
Also, what kind of isolating pads are you using under the chips, what is a purpose for them? The case is isolated itself, so no need for it, just the thermal paste.
Can you check the DC output while playing music.
Also, what kind of isolating pads are you using under the chips, what is a purpose for them? The case is isolated itself, so no need for it, just the thermal paste.
I'll check the DC output while playing music with cheap speakers this time
I'm using silicone pads, I'll replace them for thermal paste.
I'm using silicone pads, I'll replace them for thermal paste.
DC output, measuring in the speakers bananas, from almost zero to 0,14 volts max, floating a lot very fast, very instable
I remember that during both tests I heard music to about an hour
and I noticed that the cones were moving very slowly outside and inside, like slow motion, visible "aller et retours",,,
these movements are not related to the music,,,
I remember that during both tests I heard music to about an hour
and I noticed that the cones were moving very slowly outside and inside, like slow motion, visible "aller et retours",,,
these movements are not related to the music,,,
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