You haven't connect the OP secondary to ground. If so, what will happen if one
tie the two secondary 0 together?
But I guess that you haven't. Just a thought.
Rolf.
tie the two secondary 0 together?
But I guess that you haven't. Just a thought.
Rolf.
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
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.
I jumped them one at a time from negative secondary side to ground and didnt make a difference.
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.
I am getting 50k resistance from each rca jack negative to positive.I am getting 100k from rca input to input.Is this correct? (50k dact type dual pot)
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.
There's your problem, connecting the attenuator. Your reading from RCA to RCA should have been infinite.
Nope Disco, you need to rethink your analysis unless coupling caps are between those RCA jacks and the volume pot. 😀
yeah, you're right Kevin. Taking loose the ground wires to the pot and measuring again would be enlightening.
I'll do it but in a couple days from now.
Working 12 hr shifts all weekend.What would you want me to measure?
The resistance between L+R inputs should be infinite without the ground wires installed. If you get a reading some wires are misconnected or shorted.
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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