erwin_ve wrote: ↑Tue Mar 16, 2021 8:17 pm
Tony, I was looking at the #94 pics and noticed something strange at junction of the od entrance resistor and the trimpot, there seems to be a wire connected in the eyelet, going to...? Is it possible this is a od entrance with some resemblance to a 2nd gen od entrance: 220k to earth, the 1M trimmer would be a voltage divider, maybe wired under the board? Green wire seems to be connected to the trimmer at the tube side of the board.
What do you think?
Hello Erwin Here are some pics of 124's trimmer.You can see the 2 wire inserts at the bottom of the pot that (I imagine) could be the ground junctions for the cathodes to V1 &V 2. 094 has the same arrangement The strange thing is I don't see a wire protruding through the eyelet hole on the wiper that goes to the grid?..Perhaps it's under the solder.I say this because I don't see one on #94 either. We know Dumble usually likes to wrap his wires around the eyelets for some kind of physical connection before soldering therefore making it easy to spot but not in these 2 cases.We know from Gill however a wire does exist.. What has me thinking is this?
untitled1.png
(There should not be a wire there)
od entrance resistor and the trimpot, there seems to be a wire connected in the eyelet, going to...?
There is no good shot of the 220k/trimmer junction on 124?
I will look through some more shots : here is 0124.
You do not have the required permissions to view the files attached to this post.
" The psychics on my bench is the same as Dumble'"
Hello, I was able to measure grid to ground just the same in #94 as my amp. I believe that extra wire in the eyelet may have been a aborted idea for the antennae that is at the 150k eyelet. You can see the wiper grid connection in this photo. Note the .056 PS cap coming out if the clean.
CW
You do not have the required permissions to view the files attached to this post.
Thanks all! Just tried it myself and I really like it. Just for clarity are the V2 snubbers 270pf as per the low plate classic? I have 330s on the amp I did this on and it sounds very sweet but not really doing the Gregor neck pickup thing. Can't remember why I put those on years ago. I also used a glass cap instead of ceramic for the 330 treble cap. Not sure if that matters, it's what I had on hand. They are supposed to be very stable but not sure how they rate as audio caps.
scotto wrote: ↑Sun Apr 11, 2021 4:39 pm
Thanks all! Just tried it myself and I really like it. Just for clarity are the V2 snubbers 270pf as per the low plate classic? I have 330s on the amp I did this on and it sounds very sweet but not really doing the Gregor neck pickup thing. Can't remember why I put those on years ago. I also used a glass cap instead of ceramic for the 330 treble cap. Not sure if that matters, it's what I had on hand. They are supposed to be very stable but not sure how they rate as audio caps.
Did you use a 1meg trigger trimmer at the input of the OD? And the hf-taper in the OD? I never liked anything above 270pF as snubbers. I have 270 pF in my #94 based amp now and it's just the right brightness. Also, IIRC, I saw that Gregors amp was on deep mode in the clip of blue clouds (that's the one with the 68 Les Paul, right). Might be just for the clip, anyone here to confirm that his sound actually comes from deep mode, bright off
Take a look at the last picture above our posts. That is Gregors amp (or was, should I say). There is a 1meg trimmer at the OD entrance. AFAIK there is no measured value, but not too sure about that. I use a 100k trimmer in that spot. I never really like bigger trimmers, because I think the OD lacks focus because of it.
Yes, went from skyliner to classic so just the caps and left in the 150 slope. Yeah, my trimmer is also 100k. In all fairness it sounds quite good but I will change the snubbers as you mentioned. Thanks again!
Charlie Wilson wrote: ↑Sun Apr 11, 2021 6:57 pm
#94-250pf snubbers, 270pf treble cap, and a measured 1 meg OD entrance trimmer.
CW
Didn't know someone actually measured that, thanks Charlie! Have you experienced with different values of trimmers in this circuit and if so, what were your findings?
Charlie Wilson wrote: ↑Sun Apr 11, 2021 6:57 pm
#94-250pf snubbers, 270pf treble cap, and a measured 1 meg OD entrance trimmer.
CW
Didn't know someone actually measured that, thanks Charlie! Have you experienced with different values of trimmers in this circuit and if so, what were your findings?
The only higher value trimmer I have tried is the 346k or so in my low plate classic. I like the higher value trimmer, the 1 meg in #94 also sounded great. Very gainy and crunchy. I believe the .02 value HF taper cap and not having the 500pf bypass on V1B contribute to that also. I do however, prefer the 100k. I like the overdrive to be clear and open on the top end and also sound like an extension of the clean sound. The 100k does that in my amp.
CW
Cobbled together some caps I had to get to Charlie's numbers for treble and snubbers...not pretty but sounds great! Really made the difference. Thanks again Charlie. It's not dark at all though I have my TMB set at 6, 2.5 and 3...somewhat similar to what I've seen on LCs pre ripper Dumbles. It nails that tone very well. Still have the 100K trimmer. Very sweet and smooth. Bright off, deep on.
For the 270 treble cap I combined a 120 in parallel with a 500 and then another 500 in series (what I had). measured 270 on the money so tolerances were in my favor. Very ugly, but with the way it sounds I'm leaving it that way.
Here are some pics of 124's trimmer.You can see the 2 wire inserts at the bottom of the pot that (I imagine) could be the ground junctions for the cathodes to V1 &V 2. 094 has the same arrangement The strange thing is I don't see a wire protruding through the eyelet hole on the wiper that goes to the grid?..Perhaps it's under the solder.I say this because I don't see one on #94 either. We know Dumble usually likes to wrap his wires around the eyelets for some kind of physical connection before soldering therefore making it easy to spot but not in these 2 cases.We know from Gill however a wire does exist.. What has me thinking is this? (There should not be a wire there)