Hello guys … today I saw something very interesting .. there is a patent of SOLDANO for the amps jcm800 and jmp and it is called hot mod. is an adapter that accepts a tube EC10 (6K11) and greatly increases the gain on the amplifier .. put it in place of v2 and ready .. out of curiosity I searched for this patent and found only one schematic .. just looking at it I think it is wrong or am I wrong… in schematic pin 7 (the second grid of v2) has no contact anywhere .. is there a case for the signal to pass elsewhere ??
I look closely the schematic of hot mod and I see . The signal pass into the pin 8 of adapter … so the schematic is right …
I have reworked the schematic a bit. The red numbers are the pins of the adapter, the black numbers are the pins of the 6C10(6K11).
The signal comes in at pin 2 of the adapter and comes out at pin 8 of the adapter.
The 330K and 2K7 resistor have to be connected to ground but it's unclear to me how this is done in the adapter. Connecting them to one of the filament pins is ofcourse only possible if that pin is grounded. But looking at some versions of the JCM800 I mostly see that none of the filament pins are grounded because the secondary for the filaments has a grounded centre-tap. On the picture of the adapter I see a kind of metal strip/hook at the bottom. Maybe that is for the connection to ground?
The 6K10 and the 6K11 are pin compatible but they are not equivalent. The 6C10 contains 3 triodes which are identical to a triode section of a 12AX7. The 6K11 contains 2 triodes which are identical to a triode section of a 12AX7 and 1 triode that is identical to a triode section of a 12AU7.
The signal comes in at pin 2 of the adapter and comes out at pin 8 of the adapter.
The 330K and 2K7 resistor have to be connected to ground but it's unclear to me how this is done in the adapter. Connecting them to one of the filament pins is ofcourse only possible if that pin is grounded. But looking at some versions of the JCM800 I mostly see that none of the filament pins are grounded because the secondary for the filaments has a grounded centre-tap. On the picture of the adapter I see a kind of metal strip/hook at the bottom. Maybe that is for the connection to ground?
The 6K10 and the 6K11 are pin compatible but they are not equivalent. The 6C10 contains 3 triodes which are identical to a triode section of a 12AX7. The 6K11 contains 2 triodes which are identical to a triode section of a 12AX7 and 1 triode that is identical to a triode section of a 12AU7.
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What a weird hack.
If anything, mechanically unstable: that contraption will slant big time or even straight drop out of the socket on any real world bump, going to/from rehearsal room to Club or whatever.
If dedicated to mod-increase gain, why not punch a new socket hole and add a new tube the proper way?
Not even need for a full 12AX7, a tiny 6AV6 will add the same functionality (an extra triode gain stage).
If anything, mechanically unstable: that contraption will slant big time or even straight drop out of the socket on any real world bump, going to/from rehearsal room to Club or whatever.
If dedicated to mod-increase gain, why not punch a new socket hole and add a new tube the proper way?
Not even need for a full 12AX7, a tiny 6AV6 will add the same functionality (an extra triode gain stage).
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And seems to me those triple triodes are getting darn rare and all the NOS are well picked over. If you have a noisy or microphonic one and buy a "new" one, it might be worse than the one you had before.
The triple triode version of the hot mod is from the late 80's. Less trouble finding those tubes back then.
There seems to be a new version now with two regular ECC83/12AX7.
About the 'why': you don't want to cut up a vintage Marshall to add an extra socket and this mod is reversible. No need for an amp tech to install it either.
There seems to be a new version now with two regular ECC83/12AX7.
About the 'why': you don't want to cut up a vintage Marshall to add an extra socket and this mod is reversible. No need for an amp tech to install it either.
Why not?
What´so special?
I mean, from a *playing/sound* point of view.
As of "collector" point of view, there´s people who pay U$5000 for an unopened pack of 1940 Lucky Strike cigarettes.
Fine with me, but then they don´t smoke them either, don´t add new flavours, etc. , just put them in crystal cases under soft illumination in a suitably darkened and silent room to be admired.
Those old amps were not made as works of Art by any means but as Musician tools, meant to be used full blast, carried all over England and bumped against walls and van beds, every weekend.
It's a child of its time. When these appeared it was probably easier to just buy one and "plug-n-play" than find a person that does proper job of modifying your (then) rather expensive Marshall.
Today those dedicated to art of course know plenty of actually good-sounding modifications - and there are several cheap USED Marshalls to mod the sh*t out. (Or you could just buy cheap Laney AOR - or a Jet City if you want a Soldano-style modded Marshall).
And realistically, one can't just randomly fit an extra tube to Marshall and end up with great results. Not to mention, average guitarist wouldn't even have a slightest blue how to do so. In fact, the average guitarists didn't even grasp the concept that this Hotmod works only in specific limited number of amps. Not in V2 of any amp, not even in V2 of any Marshall.
Today those dedicated to art of course know plenty of actually good-sounding modifications - and there are several cheap USED Marshalls to mod the sh*t out. (Or you could just buy cheap Laney AOR - or a Jet City if you want a Soldano-style modded Marshall).
And realistically, one can't just randomly fit an extra tube to Marshall and end up with great results. Not to mention, average guitarist wouldn't even have a slightest blue how to do so. In fact, the average guitarists didn't even grasp the concept that this Hotmod works only in specific limited number of amps. Not in V2 of any amp, not even in V2 of any Marshall.
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