Did some searching and reading and didn't find anything about the bias so I fired her up and she's singing now.
This mod is more than noticeable to me. Detail is through the roof but it's not harsh at all. Quite the opposite actually. I'm blown away. Just lush and glorious with a wide and deep soundstage and amazing layers to the imaging. It really sounds better in every way.
This mod is more than noticeable to me. Detail is through the roof but it's not harsh at all. Quite the opposite actually. I'm blown away. Just lush and glorious with a wide and deep soundstage and amazing layers to the imaging. It really sounds better in every way.
Just set the bias to the normal figure (0.35V). Have you tried removing the negative feedback?
In theory with true Triodes, because they are more linear then there is no need for negative feedback or at least a much reduced amount. I have no idea what the MC10 would sound like in Triode mode with no feedback. Just carefully cut one leg of the 5k1 resistor and the 100pF capacitor. Carefully means try to leave a piece of wire sticking up from the board so you can re-solder the components without having to do a major strip down :-D.
In theory with true Triodes, because they are more linear then there is no need for negative feedback or at least a much reduced amount. I have no idea what the MC10 would sound like in Triode mode with no feedback. Just carefully cut one leg of the 5k1 resistor and the 100pF capacitor. Carefully means try to leave a piece of wire sticking up from the board so you can re-solder the components without having to do a major strip down :-D.
Okay, found 'em and clipped 'em. They're on the pre-amp board, small components right next to each other, one set for the left channel and one set for the right, the cap is a small ceramic.
Um, Les...this is nothing short of amazing. I've only listed to 5 songs that I'm very familiar with so far:
Pink Floyd:
Another Brick in The Wall pt.1
The Happiest Days of Our Lives
Another Brick in The Wall pt.2
Mother
The Modern Jazz Quartet:
Bag's Groove (The Last Concert)
The detail is just crazy. I'm noticing things on these tracks that I've never noticed before. Tom drums sound so lifelike, cymbals are metallic and each strike has it's own slightly different sound, highs are much clearer and less harsh, everything has tightened up nicely. All of the background noises and voices on "The Wall" tracks are more intelligible and easier to place.
You're up Barbieboy!
Um, Les...this is nothing short of amazing. I've only listed to 5 songs that I'm very familiar with so far:
Pink Floyd:
Another Brick in The Wall pt.1
The Happiest Days of Our Lives
Another Brick in The Wall pt.2
Mother
The Modern Jazz Quartet:
Bag's Groove (The Last Concert)
The detail is just crazy. I'm noticing things on these tracks that I've never noticed before. Tom drums sound so lifelike, cymbals are metallic and each strike has it's own slightly different sound, highs are much clearer and less harsh, everything has tightened up nicely. All of the background noises and voices on "The Wall" tracks are more intelligible and easier to place.
You're up Barbieboy!
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Yep, that's what I have.
An externally hosted image should be here but it was not working when we last tested it.
Yes the psycho-acoustics can be very real. I notice this a lot on re-mixing where just shifting of the levels is required and one is easily fooled into thinking it sounds better, frequency wise :-D
Now if I had done what you done so far i.e. removing the NFB, I would at least try to set up the phase splitter outputs to give the least harmonic distortion. Without any test gear this really is a no-go but then you probably are not hearing any more distortion than normal? If you have a dual channel oscilloscope you can use that to give a reasonable assessment of equal and opposite drive to the output tube grids.
Now if I had done what you done so far i.e. removing the NFB, I would at least try to set up the phase splitter outputs to give the least harmonic distortion. Without any test gear this really is a no-go but then you probably are not hearing any more distortion than normal? If you have a dual channel oscilloscope you can use that to give a reasonable assessment of equal and opposite drive to the output tube grids.
It really doesn't matter, take the MS22/23, probably checked out with audio analyzers we would die for when it was first put together yet it sounds 
If the amp sounds good, with an recognizable amount of distortion and brings lots of joy to the listener then surely that's what it is all about.
If the amp sounds good, with an recognizable amount of distortion and brings lots of joy to the listener then surely that's what it is all about.
I'm not sure about the reverb thing but I find it more enjoyable to listen to now. More separation and layers to the performance yet somehow more ethereal and blooming. Transients have improved as well. On some Pat Metheny stuff that has weird noises created by solid object or severely out of tune instruments I hear the attack of the noise more clearly now.
Over all I feel that the triode/0-nfb mod made the amp considerably more musical and enjoyable to listed to.
Over all I feel that the triode/0-nfb mod made the amp considerably more musical and enjoyable to listed to.