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Multiple Preamplifier Disorder

Started by THChrist, October 11, 2009, 01:20:48 PM

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THChrist

Hello everybody!

I wanted to share this with you. It's a simplifyed version of the pramp I'm desingning. It consists of multiple bypassable stages, switchable mods and it was designed using 3 Marshall Amps: 1959SLP (1 stage + pre-eq gain), JCM800 2203 (2 stages + pre-eq gain) and JCM900SL-X (3 stages + pre-eq gain). Each stage consists of a Noiseless biased SRPP using FETs

There are switchable mods: Bright cap, Boost (only for modes 2 and 3), Thick (for the 3 modes) and modable Tonestack (33k-470p/56k-220p/46k-690p).

I recommend you to use @15-18v

Here's the schematic:

http://i20.photobucket.com/albums/b228/Anti-Idiot/MPD-SingleVersion.jpg

EDIT: I forgot, please excuse me for not numbering each component, i'll do it ASAP. If you need to point something out, the reference is: 1st stage, 3rd stage, 2nd stage and pre-EQ stage. Also, the LED is a multicolored LED (R/G).

This is a single version. the other version should have 3 gains and 3 tonestacks with volume per channel (15 pots), output buffer, master volume, internal switching using relays (for bypassing stages and switching the gain/tonestacks), external channel switching (using this switching) and poweramp w/presence & resonance (this one). BTWm there's a mistake in the PA section, change the value of the 100u cap to 1u.


Please ask.

Zappacat

Quote from: THChrist on October 11, 2009, 01:20:48 PM
Hello everybody!

I wanted to share this with you. It's a simplifyed version of the pramp I'm desingning. It consists of multiple bypassable stages, switchable mods and it was designed using 3 Marshall Amps: 1959SLP (1 stage + pre-eq gain), JCM800 2203 (2 stages + pre-eq gain) and JCM900SL-X (3 stages + pre-eq gain). Each stage consists of a Noiseless biased SRPP using FETs

There are switchable mods: Bright cap, Boost (only for modes 2 and 3), Thick (for the 3 modes) and modable Tonestack (33k-470p/56k-220p/46k-690p).

I recommend you to use @15-18v

Here's the schematic:

http://i20.photobucket.com/albums/b228/Anti-Idiot/MPD-SingleVersion.jpg

EDIT: I forgot, please excuse me for not numbering each component, i'll do it ASAP. If you need to point something out, the reference is: 1st stage, 3rd stage, 2nd stage and pre-EQ stage. Also, the LED is a multicolored LED (R/G).

This is a single version. the other version should have 3 gains and 3 tonestacks with volume per channel (15 pots), output buffer, master volume, internal switching using relays (for bypassing stages and switching the gain/tonestacks), external channel switching (using this switching) and poweramp w/presence & resonance (this one). BTWm there's a mistake in the PA section, change the value of the 100u cap to 1u.


Please ask.

I was really excited about seeing this schematic until I got to the "page not found error" on photobucket.  Why not post it here?
I put my pants on just like the rest of you - one leg at a time. Except, once my pants are on, I make gold records.

THChrist

#2
Quote from: Zappacat on October 28, 2009, 01:37:16 AM
Quote from: THChrist on October 11, 2009, 01:20:48 PM
Hello everybody!

I wanted to bla bla bla

I was really excited about seeing this schematic until I got to the "page not found error" on photobucket.  Why not post it here?

Well, i made a few changes (at DIYstompboxes) and i forgot to edit it over here. Sorry.

Here's the final version of the MPD:

http://i20.photobucket.com/albums/b228/Anti-Idiot/MPD-Simple.jpg

As you can see, stage 3 comes before stage 2. in order to use the stage 3, u need to turn on the stage 2.