What level of OT plate voltages are we talking about??ayan wrote:...Before being turned into a 100K amp, it was a higher plate Classic, then a higher plate Skyliner amp. It didn't shine until the last conversion.
Gil
Thoughts on 100k plate amp, #124, and my Clone
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bluesfendermanblues
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Re: Thoughts on 100k plate amp, #124, and my Clone
Re: Thoughts on 100k plate amp, #124, and my Clone
With my Marshall style iron, about 485 VDC or so. ODS 124 had probably around 430 VDC.bluesfendermanblues wrote:What level of OT plate voltages are we talking about??ayan wrote:...Before being turned into a 100K amp, it was a higher plate Classic, then a higher plate Skyliner amp. It didn't shine until the last conversion.
Gil
Gil
Just some thoughts....
**The following post may contain little, or no useful information***
After spending a few hours with my #124 clone amp and a box of tubes and resistors these are my impressions:
1) My Used Old Stock RCA 12AX7s sounded better with 100k plate topology. They did not have as much gain and clarity with 220k plates.
2) My New and Old Chinese 12AX7s sounded better with 220/150k plate topology.
3) The PI tube has just as much effect on the tone as the "distorting tube" ( V2.) This is more of an effect than I realized, or expected (though Gil and others has posted about it many times
)
4) Gil has stated that he never heard #124 after it received new capacitors. Therefore it is perhaps futile to compare my amp with an amp that no one on these boards has ever heard!
So, perhaps, with an appropriate assortment of tubes, and the actual correct Shumacher transformer, I could imagine the #124 schematic might sound pretty good without having to guess about 'secret electrical components' or invoke any additional 'tonal support' from angels, UFOs, or the Ghost of Elvis
After spending a few hours with my #124 clone amp and a box of tubes and resistors these are my impressions:
1) My Used Old Stock RCA 12AX7s sounded better with 100k plate topology. They did not have as much gain and clarity with 220k plates.
2) My New and Old Chinese 12AX7s sounded better with 220/150k plate topology.
3) The PI tube has just as much effect on the tone as the "distorting tube" ( V2.) This is more of an effect than I realized, or expected (though Gil and others has posted about it many times
) 4) Gil has stated that he never heard #124 after it received new capacitors. Therefore it is perhaps futile to compare my amp with an amp that no one on these boards has ever heard!
So, perhaps, with an appropriate assortment of tubes, and the actual correct Shumacher transformer, I could imagine the #124 schematic might sound pretty good without having to guess about 'secret electrical components' or invoke any additional 'tonal support' from angels, UFOs, or the Ghost of Elvis
Re: Thoughts on 100k plate amp, #124, and my Clone
So, at least for today, I have wound up with 100k and an RCA tube on V1 and 220/150k and a Chinese tube on V2. My fingers are tired from all the tube testing, but sound clips to follow....
OOPS!!
Just going over my amp and the schematics that I had posted and somehow a 100k resistor got into the grid position of the second OD stage! (Both in the schematic and in the amp!)ic-racer wrote: C) Improper build
D) Error in (my!) #124 schematic
It really sounds a lot better with the correct value of 180k there!
Looking back at the #124 schematic in the 'files' section I can see where this error occurred. The 'eight' on that schematic looks like a 'zero' on my computer screen.
I was re-wiring the 500p cap on V1, and looking at the #124 pictures when I saw the gray band and caught my mistake.