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Summing channels;Why? JE EL34

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Hi everybody

If the sound levels are the same in both speakers with only one input connected it should be a short between the channels near the inputs.

Cross-talk never give the same levels on both sides. If so it is a short.

Did you carefully look at the wiring of the input pots ?

Can you check that both pots have one side connected to the ground ?

If the ground is missing the path for the right signal to the left side is free and vive versa.

COurage

Jacques
 
Ok, do you have the speakers connected BETWEEN the L and R outputs?
That is, one speaker connected between the two red posts, and the other speaker
connected between the two black posts? That could do something like you are describing,
since the output transformers' secondaries are floating and ungrounded.
No sir, They are correct.Am working another 12 hr shift tomorrow, will look again thursday. i will take a closer look at my grounds to the input but its all pretty obvious and I dont see a problem there. (yeah I know, its somewhere) You guys are very helpful and I do appreciate all the suggestions.
 
Hi everybody

If the sound levels are the same in both speakers with only one input connected it should be a short between the channels near the inputs.

Cross-talk never give the same levels on both sides. If so it is a short.

Did you carefully look at the wiring of the input pots ?

Can you check that both pots have one side connected to the ground ?

If the ground is missing the path for the right signal to the left side is free and vive versa.

COurage

Jacques
I will jumper each one of them with a separate ground thursday AM.They already have separate grounds directly to a ground buss, but I will recheck.
 
Wanted to follow up this thread.I added a small choke (parts box) and a 47ufd capacitor off the B+before the driver circuit.Crosstalk is eliminated. I also switched to an SRPP driver which I think sounds worlds more musical and dynamic than the previous parallelled 6sl7 sections.Not perfect but worlds better in my opinion. 310 volts to the plate of 6sl7.I used 1k resistors and 175k grid leak resistors.How hot can I run the driver?Getting 1.2 volts at the cathode.
 
Wanted to follow up this thread.I added a small choke (parts box) and a 47ufd capacitor off the B+before the driver circuit.Crosstalk is eliminated. I also switched to an SRPP driver which I think sounds worlds more musical and dynamic than the previous parallelled 6sl7 sections.Not perfect but worlds better in my opinion. 310 volts to the plate of 6sl7.I used 1k resistors and 175k grid leak resistors.How hot can I run the driver?Getting 1.2 volts at the cathode.

Hey that thread made be smile :) I would go crazy at your place

Choke added : before the driver circuit, you mean after the voltage B+ reducer 27k Resistor, I am confused because there is a capacitor on the schematic, maybe you just omit it before?

If you have super high sensitivity speakers 95db + an unfiltered B+ from power tube could modulate a signal and amplified by the other section... this is absolutely breathtaking that the design could be so horrible
 
Hey that thread made be smile :) I would go crazy at your place

Choke added : before the driver circuit, you mean after the voltage B+ reducer 27k Resistor, I am confused because there is a capacitor on the schematic, maybe you just omit it before?

If you have super high sensitivity speakers 95db + an unfiltered B+ from power tube could modulate a signal and amplified by the other section... this is absolutely breathtaking that the design could be so horrible
Choke and cap added before driver circuit,right before cap and 27k resistor, just added another filter section to the driver. Using Cornwall clones and Chorus I's.Was using (2) caps and (2) chokes for the B+, now a 3rd choke.Cap input, bridge rectified. Finally dead silent.
 
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