I am pulling the diode string

[Clyde]

I had 1N4007's in my amp, thought they added some artifacts too, so out they came.

[jurgen]

I've heard the sound described above from time to time.

I play 11s and have pretty heavy right hand so I'd thought the problem

might be blocking distorion right at the first triode but then I'm not sure I

actually know what blocking distortion would sound like.

[jurgen]

Thinking back

I heard it more with 6v6s than EL34s

[prspastor]

Well, ever since I fixed the pin 1 grounding issue I had a month or so back, I've really had a chance to listen to the overdrive characteristics of my amp. There was something in there that I was not liking - noise and a slight fizz - that was not musical. I took out the diode string and the noise is gone.

Huh, wonder what is going on in all of these instances - leaking voltage?

I tested the 1N4007 diodes and they all test good.

[fishy]

I'm thinking the diode string might be the issue for me too.Although I have looked at the posts regarding them, it did not really click. Imagine that

Lately, I have had some time to play a little and regardless of which guitar I plug in I get that oscillation, blurring of the note when you really dig in higher up the neck. Not every note but it is definitely not cool!
It does it with a variety of guitars, with different speakers.....

Those diodes are coming out...

[Cameron]

Well, ever since I fixed the pin 1 grounding issue I had a month or so back, I've really had a chance to listen to the overdrive characteristics of my amp. There was something in there that I was not liking - noise and a slight fizz - that was not musical. I took out the diode string and the noise is gone.

Huh, wonder what is going on in all of these instances - leaking voltage?

I tested the 1N4007 diodes and they all test good.

What you are hearing is the diodes clipping......that is what this does. If you put just one diode you would hear it more. Three takes it just out of range for you to hear(but you will still hear it at hi-volume)...... Simply it stops the signal from going over a voltage set by the diodes....so if something goes wrong.... the transformer takes less of a hit before the fuse blows.

[Cameron]

sorry double post

[jckid649]

Well, ever since I fixed the pin 1 grounding issue I had a month or so back, I've really had a chance to listen to the overdrive characteristics of my amp. There was something in there that I was not liking - noise and a slight fizz - that was not musical. I took out the diode string and the noise is gone.

Huh, wonder what is going on in all of these instances - leaking voltage?

I tested the 1N4007 diodes and they all test good.

What you are hearing is the diodes clipping......that is what this does. If you put just one diode you would hear it more. Three takes it just out of range for you to hear(but you will still hear it at hi-volume)...... Simply it stops the signal from going over a voltage set by the diodes....so if something goes wrong.... the transformer takes less of a hit before the fuse blows.

Then what would happen if you used 4, would it be beyond hearing altogether. Is there an upper limit on how many diodes you can use together here?

[Cameron]

Well, ever since I fixed the pin 1 grounding issue I had a month or so back, I've really had a chance to listen to the overdrive characteristics of my amp. There was something in there that I was not liking - noise and a slight fizz - that was not musical. I took out the diode string and the noise is gone.

Huh, wonder what is going on in all of these instances - leaking voltage?

I tested the 1N4007 diodes and they all test good.

What you are hearing is the diodes clipping......that is what this does. If you put just one diode you would hear it more. Three takes it just out of range for you to hear(but you will still hear it at hi-volume)...... Simply it stops the signal from going over a voltage set by the diodes....so if something goes wrong.... the transformer takes less of a hit before the fuse blows.

Then what would happen if you used 4, would it be beyond hearing altogether. Is there an upper limit on how many diodes you can use together here?

I would just take them out. You could raise the screens to 2.2k and get some of the tone back. The diodes are part of the tone of this amp.