1. Forgot to ground the pot to the chassis. Oops! Rookie mistake... I'll fix that.
2. It definitely is static and happens not just when I turn the pot, but constantly. I'll try reflowing the joints if grounding the pot doesn't do the trick. I do have a new scope as well (early birthday gift to myself) so I can measure stuff if need be.
Will report back with results this evening.
Thanks all!
2. It definitely is static and happens not just when I turn the pot, but constantly. I'll try reflowing the joints if grounding the pot doesn't do the trick. I do have a new scope as well (early birthday gift to myself) so I can measure stuff if need be.
Will report back with results this evening.
Thanks all!
I had something similar to static in a decent project, during turn on for a minute.
Turned out to be a bad solder joint, trying to solder in a small wire into a big hole
I would measure the usual places - where the power supply section stops for voltages there - and across the 2SK's, and then the output as well for DC offset, AND AC.
If you got a scope that would help
Good news is the static went away when I grounded the pot. Bad news is that the left channel is no longer audible and the pot isn't working as it should. I believe I must have mis-wired the pot after all. Going to double check now.
In the meantime, can someone verify the pot wiring for me?
For the output of the board, it's just the three pins to the output RCAs.
For the input... here's what I think I'm supposed to have.
RCA in to the left pin (looking down at an ALPS pot with the shaft pointing toward you). RCA ground to the right pin. Middle pin to the B1 board.
Also, I tied the RCA input grounds together... is that ok?
EDIT: SUCCESS! I had not tied the left and right grounds together.
Still need a volume knob.
In the meantime, can someone verify the pot wiring for me?
For the output of the board, it's just the three pins to the output RCAs.
For the input... here's what I think I'm supposed to have.
RCA in to the left pin (looking down at an ALPS pot with the shaft pointing toward you). RCA ground to the right pin. Middle pin to the B1 board.
Also, I tied the RCA input grounds together... is that ok?
EDIT: SUCCESS! I had not tied the left and right grounds together.
Still need a volume knob.
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I finally decided to install a couple of 4.5R mills resistors i had on hand, which replaced the Mills 10R. Resolution was a very nice bump, well worth the effort. Barely ran warm before but running about 100 degress on the sinks (37.7 celsius).
Cant find acceptable temp ranges, thanks. Using large L bars bolted to chassi
Is 100 degrees an acceptable temp?
Cant find acceptable temp ranges, thanks. Using large L bars bolted to chassi
Is 100 degrees an acceptable temp?
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I went from 10R to 3R0 and the sinks got too hot for my liking, They were stable at about 55 Degrees C.
I might just try 4R7 as you have - allbeit 4R5 in your case.
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I still cant see why mine were getting so warm at 3R0.
Maybe I was just being too cautious. After about 30 mins with the lid off my sinks were at 55 Degrees C or so. I felt, that, with the lid on, things would just get too warm and things would start to fail.
Maybe that's me being too cautious. Maybe 3R0 was too far. I am tempted to try 4R7 though - I've already ordered them.
I seem to recall that the heatsinks were about 3.6 Deg C/W. I've used one per side so there are two IRFPs on each sink.
At 10R0 they run at about 30-35 Degrees C.
Maybe I was just being too cautious. After about 30 mins with the lid off my sinks were at 55 Degrees C or so. I felt, that, with the lid on, things would just get too warm and things would start to fail.
Maybe that's me being too cautious. Maybe 3R0 was too far. I am tempted to try 4R7 though - I've already ordered them.
I seem to recall that the heatsinks were about 3.6 Deg C/W. I've used one per side so there are two IRFPs on each sink.
At 10R0 they run at about 30-35 Degrees C.
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Attenuator question
I'm planning a 6-channel DCB1 along these lines:
with Hypnotize boards in place of the DACT modules.
DACT recommends 10K pots for the master and individual channel controls, while Mr. Pass recommends a nominal 25K. I've a mind to use 20K as a compromise (PEC carbon for each channel and Goldpoint for the master), though I don't know how having two pots in a row affects the total input impedance. Can anyone enlighten me as to how the attenuator impedance affects the sound? Any recommendations?
I'm planning a 6-channel DCB1 along these lines:
with Hypnotize boards in place of the DACT modules.
DACT recommends 10K pots for the master and individual channel controls, while Mr. Pass recommends a nominal 25K. I've a mind to use 20K as a compromise (PEC carbon for each channel and Goldpoint for the master), though I don't know how having two pots in a row affects the total input impedance. Can anyone enlighten me as to how the attenuator impedance affects the sound? Any recommendations?
A pair of series connected pots to control volume !!!!!
Have you considered each pot as a receiver and then again as a transmitter?
The Source sees the pot1 and the cable in between.
Pot1 sees the source and the cable in between.
Pot2 sees pot1 and the cable in between.
Pot1 sees pot2 and the cable in between.
Pot2 sees the DCB1 and the cable in between.
The DCB1 sees pot2 and the cable in between.
You have six IN/OUT systems from Source to DCB1.
You must satisfy good practice in transferring signal through all six systems.
What you are proposing has not been thought through thoroughly.
Have you considered each pot as a receiver and then again as a transmitter?
The Source sees the pot1 and the cable in between.
Pot1 sees the source and the cable in between.
Pot2 sees pot1 and the cable in between.
Pot1 sees pot2 and the cable in between.
Pot2 sees the DCB1 and the cable in between.
The DCB1 sees pot2 and the cable in between.
You have six IN/OUT systems from Source to DCB1.
You must satisfy good practice in transferring signal through all six systems.
What you are proposing has not been thought through thoroughly.