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previous: Ray Ivers Dale,The wireless u... -- 4/22/2000 3:54 PM

Re: Marshall (and other) Hum Sources

4/22/2000 5:49 PM
anonymous	Re: Marshall (and other) Hum Sources hi ray, while we're on the subject of diode clipping, i have a qestion or 2 about it. i had a 900, and i removed all the diodes from the circuiit, and used a resistor in place of the diode bridge to keep the gain similar. the results were that the amp was less buzzy and rounder. now i have a silver jubilee 25th anniversary marshall, which also has diode clipping. however, the diode clipping circuit looks vastly different from the 900. could you look at the schematic and tell me what you think about removing them? here it is--- http://www.ampage.org/blueguitar/2550.gif>http://www.ampage.org/blueguitar/2550.gif looking at it, it appears to me, tho i'm no tech, that the way it works in this circuit, it would use less diode clipping with the lead master way down and the overall master all the way up. can you tell if thats the case looking at it? also, i didn't want to even touch the circuit board because this is a mint condition amp that is a collectors item, and i just don't feel good about messing with it even tho i can reverse it if i want. but if you think i can gain some tone quality by removing the diodes i'd do it. as far as losing some gain, thats no problem cuz it has more gain than i need anyway. i usually keep the gain at about 1:00. plus the gain turned up gives it the best tone as far as thickness goes, but at that point theres too much gain for me. so maybe it would be good to lose some so i could turn the gain all the way up to get the amount i like and gain an even thicker tone. so if you could look at the schematic and tell me your thoughts i'd appriciate it, as you seem to be very knolledgable about this stuff. thanks,--dale

4/22/2000 5:49 PM

anonymous

Re: Marshall (and other) Hum Sources

hi ray,

while we're on the subject of diode clipping, i have a qestion or 2 about it. i had a 900, and i removed all the diodes from the circuiit, and used a resistor in place of the diode bridge to keep the gain similar. the results were that the amp was less buzzy and rounder. now i have a silver jubilee 25th anniversary marshall, which also has diode clipping. however, the diode clipping circuit looks vastly different from the 900. could you look at the schematic and tell me what you think about removing them? here it is---
http://www.ampage.org/blueguitar/2550.gif>http://www.ampage.org/blueguitar/2550.gif

looking at it, it appears to me, tho i'm no tech, that the way it works in this circuit, it would use less diode clipping with the lead master way down and the overall master all the way up. can you tell if thats the case looking at it?

also, i didn't want to even touch the circuit board because this is a mint condition amp that is a collectors item, and i just don't feel good about messing with it even tho i can reverse it if i want. but if you think i can gain some tone quality by removing the diodes i'd do it. as far as losing some gain, thats no problem cuz it has more gain than i need anyway. i usually keep the gain at about 1:00. plus the gain turned up gives it the best tone as far as thickness goes, but at that point theres too much gain for me. so maybe it would be good to lose some so i could turn the gain all the way up to get the amount i like and gain an even thicker tone. so if you could look at the schematic and tell me your thoughts i'd appriciate it, as you seem to be very knolledgable about this stuff.

thanks,--dale

Replies:

Ray Ivers Marshall Jubilee/JCM900 MV/DR Mods -- 4/22/2000 9:31 PM
Tonefactor Re: Marshall (and other) Hum Sources -- 4/25/2000 10:13 PM