Fender Blues Jr noise ?

[gtrplayr1976]

I'll admit the designation between the two is confusing? The BJ does have an unused triode in it. Looking at the Hoffman layout I see that it too has one and it simply isn't connected to anything, where the PCB Fender has the pins grounded. I'm pretty sure it doesn't matter either way.

Actually Doug uses both halves paralleled (although in my brain it looks series)lol. He said it adds a bit more gain. I really don't want extra gain since I'm trying to clean it up ,so I can just leave half unconnected ?

[The Dude]

Yes. There are plenty of amps out there with unused triodes.

[Chuck H]

Actually Doug uses both halves paralleled (although in my brain it looks series)lol. He said it adds a bit more gain. I really don't want extra gain since I'm trying to clean it up ,so I can just leave half unconnected ?

Oh, I see that now. The drawing has a lot of diagonal liney things going on and I just missed it

By paralleling the triodes without any value changes you get a little lower impedance. This could make for a tad more output and top end because there's less signal lost to any loading. And since impedance rises with frequency, but you're starting point is a lower impedance... You get it. So, it's a stronger and more linear signal. Not higher in gain at face value but less prone to lose anything getting to the next grid. Sort of. That's the VERY simplified version. I don't think that should be the cause of your problem. The exception being if any increase in HF OVERALL is contributing to crosstalk. I doubt it. But I'm also out of ideas right now.

[gtrplayr1976]

Oh, I see that now. The drawing has a lot of diagonal liney things going on and I just missed it

By paralleling the triodes without any value changes you get a little lower impedance. This could make for a tad more output and top end because there's less signal lost to any loading. And since impedance rises with frequency, but you're starting point is a lower impedance... You get it. So, it's a stronger and more linear signal. Not higher in gain at face value but less prone to lose anything getting to the next grid. Sort of. That's the VERY simplified version. I don't think that should be the cause of your problem. The exception being if any increase in HF OVERALL is contributing to crosstalk. I doubt it. But I'm also out of ideas right now.

I didn't think it was the problem either. I had the same problem with the circuit board. Guess I'll try a scope.

[gtrplayr1976]

Still trying to track down this noise. I was told of a way to connect a guitar directly to each grid using an input jack ,and a piece of shielded cable. The only thing was at the PI not to connect directly to the grid , but at the input cap. When I did that all I got was static as I increased the guitar volume. Do I have it connected correctly ? Have I missed something ? Does the input jack need to be isolated ?

[gtrplayr1976]

FIXED.

Oh, I see that now. The drawing has a lot of diagonal liney things going on and I just missed it

By paralleling the triodes without any value changes you get a little lower impedance. This could make for a tad more output and top end because there's less signal lost to any loading. And since impedance rises with frequency, but you're starting point is a lower impedance... You get it. So, it's a stronger and more linear signal. Not higher in gain at face value but less prone to lose anything getting to the next grid. Sort of. That's the VERY simplified version. I don't think that should be the cause of your problem. The exception being if any increase in HF OVERALL is contributing to crosstalk. I doubt it. But I'm also out of ideas right now.

Well Chuck. I got it fixed. Embarrassed to say most of it was a bad speaker. Yes I did try another cab. lol..apparently it also has a bad speaker. I'm just glad this headache is almost over. (I hope) On to the next friends project (headache) 60s Gretsch Chet Atkins. I already can't find a schematic. lol

[g1]

That would be Gretsch 6160, but please start a new thread.

[gtrplayr1976]

That would be Gretsch 6160, but please start a new thread.

Oh absolutely. It is not a 6160. Doesn't even come close to the schematic. Closest one I've found is for the Fury 6169 ,and that one isn't correct either. It's a piggyback with a 1x15 ,and 1x12 cab. Two OTs , and one of the tubes is a 6973. It has 4 x5881s. BUT I will do this on another thread. Thanks g1 !