Matchless preamp marshall pa.

General discussion area for tube amps.

Moderators: pompeiisneaks, Colossal

Post Reply
Andyjoe
Posts: 24
Joined: Fri Mar 30, 2007 1:49 am
Location: Louisiana

Matchless preamp marshall pa.

Post by Andyjoe »

Has anyone tried this. I made a lightning clone and loved the cleans but the od was too fizzy. I would like to make a amp with one voxish channel and the other 18 watt with the marshall power amp and pi.

Andy
User avatar
roberto
Posts: 1841
Joined: Tue Nov 27, 2007 4:45 pm
Location: Italy

Re: Matchless preamp marshall pa.

Post by roberto »

Can you post the schematic you are using at the moment?
It will be easier.
Andyjoe
Posts: 24
Joined: Fri Mar 30, 2007 1:49 am
Location: Louisiana

Re: Matchless preamp marshall pa.

Post by Andyjoe »

Just a idea. I built the 18 watt from schematics off of the 18 watt forum.
I built the lightning from the schematic on the prowess site, now I bought a new blank chassis and trying to come up with something.
User avatar
roberto
Posts: 1841
Joined: Tue Nov 27, 2007 4:45 pm
Location: Italy

Re: Matchless preamp marshall pa.

Post by roberto »

Basically a lightning preamp ( http://www.diyguitarist.com/Schematics/ ... ematic.gif ) into a marshall 1974 power amp ( http://www.drtube.com/schematics/marshall/18w.gif ) ?

As I said, it would be easier to help you also with impressions if you'll give more details.
Andyjoe
Posts: 24
Joined: Fri Mar 30, 2007 1:49 am
Location: Louisiana

Re: Matchless preamp marshall pa.

Post by Andyjoe »

Let me change my question. What would a vox style amp sound like with a marshall pi and pa?
printer2
Posts: 146
Joined: Sat Jun 26, 2010 5:14 am
Location: Canada

Re: Matchless preamp marshall pa.

Post by printer2 »

Moxie?
Andyjoe
Posts: 24
Joined: Fri Mar 30, 2007 1:49 am
Location: Louisiana

Re: Matchless preamp marshall pa.

Post by Andyjoe »

Voshall :D
User avatar
LeftyStrat
Posts: 3117
Joined: Fri Jan 14, 2005 6:58 pm
Location: Marietta, SC, but my heart and two of my kids are in Seattle, WA

Re: Matchless preamp marshall pa.

Post by LeftyStrat »

Just build a half power Rocket if you're looking for something in the 18 watt range. The Rocket is based on an AC30.
It's never too late to have a happy childhood.
User avatar
malt
Posts: 127
Joined: Tue Jan 18, 2005 8:00 pm
Location: NOrWAY

Re: Matchless preamp marshall pa.

Post by malt »

Hi, check out Mark Durham's Vajra
I'll tell you all my secrets, but I lie about my past.
User avatar
roberto
Posts: 1841
Joined: Tue Nov 27, 2007 4:45 pm
Location: Italy

Re: Matchless preamp marshall pa.

Post by roberto »

dass101
Posts: 27
Joined: Mon Oct 31, 2011 10:33 am

Re: Matchless preamp marshall pa.

Post by dass101 »

The way I see it, the main difference is the 820 vs 1.5K resistor in the PI. It won't make much of a difference, I tried it.

Which Lightning schematic did you use? There are 2 versions, one is, IMO, incorrect.
The correct one, that brings out all the good crunch and chime from the amp, is without the separate screen voltage (screen feeds directly from the second cap) and with 4.7K resistor in the second stage supply.

If you want to reduce the fizz, you should install a 500k pot as divider after the treble pot, going into PI, instead of the fixed 220k/100k divider. This is where most of the fizz happens, with the pot you can adjust to taste.
Post Reply