Mesa Boogie Blue Angel - What do V1b ?

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Kagliostro
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Mesa Boogie Blue Angel - What do V1b ?

Post by Kagliostro »

Not sure about but seems (to me) that the schematic of pre in MB Blue Angel was drawn wrongly

is V1b a cathode follower missing of the connection to the next stage and the connection of V1a plate to the next stage is wrong

or V1b is there for a "special" purpose

I would like to know your opinions

Many Thanks

K

p.s.: I just noticed that in the faceplate of Blue Angel there is a Bright/Fat switch that seem to be missing in the schematic
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Vince
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Re: Mesa Boogie Blue Angel - What do V1b ?

Post by Vince »

Kagliostro wrote:p.s.: I just noticed that in the faceplate of Blue Angel there is a Bright/Fat switch that seem to be missing in the schematic
Missing switch reveals mystery of V1b :)
Check Maverick schematic:
http://www.freeinfosociety.com/electron ... erick1.jpg
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roberto
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Re: Mesa Boogie Blue Angel - What do V1b ?

Post by roberto »

You can see the bright/fat switch on the 180pF added treble cap in the tonestack. There are no other switches, otherwise I suggeste you something like a spst that take the signal from grid or cathode of V1b to have a fat sound or not (both for the CF effect, both for the lower input impedance for the tonestack).
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roberto
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Re: Mesa Boogie Blue Angel - What do V1b ?

Post by roberto »

Ok, I've seen now the Maverik schematic: It's a dpdt switch for both the treble cap and the V1b's grid/cathode signal:
http://i210.photobucket.com/albums/bb34 ... lGuts1.jpg
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Kagliostro
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Re: Mesa Boogie Blue Angel - What do V1b ?

Post by Kagliostro »

Many Thanks

I think Maverik's schematic and Blue Angel guts clarify the situation

K
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