2 channel amplifier based on Plexi and JCM800
Posted: Thu May 18, 2023 6:08 pm
Hello! My name is Antonio and I live in Brazil.
I have a 2-channel handmade amplifier, one of them being Clean (based on Plexi) and the other, a Dirty channel (based on JCM800). On the JCM Channel, I have the option to use stock mode 2204 and mods #34 and #36 by Frank Levi.
Analyzing the construction, I had some doubts. I will be very happy if someone can help me with them.
1) I use 2 tubes 6550s in the power and I have a switch that allows to change the operation between triode mode and pentode mode. Do 6550s tubes go well in triode mode? Is there any risk in using triode mode? I ask this because I'm thinking of removing this switch that changes the modes.
2) The dirty and clean channels use halves of the first 12AX7, with half of the first triode for the dirty channel and the other half for the clean channel. As a way of connecting the 2 channels to the input, the builder connected the 2 grids of the triodes (check the photo). Is this a good solution? Is there any way to make this better? Is there a change in pitch or signal strength?
https://drive.google.com/file/d/1zSpgsI ... sp=sharing
These are some pictures of my amplifier's internal components. Do you have any suggestions for me? I want to get as close to a good Marshall sound as possible.
https://drive.google.com/file/d/1Hsou8I ... sp=sharing
https://drive.google.com/file/d/18WOXmv ... sp=sharing
https://drive.google.com/file/d/1e9U4Db ... sp=sharing
Thank you very much!
Kind regards,
Antonio.
I have a 2-channel handmade amplifier, one of them being Clean (based on Plexi) and the other, a Dirty channel (based on JCM800). On the JCM Channel, I have the option to use stock mode 2204 and mods #34 and #36 by Frank Levi.
Analyzing the construction, I had some doubts. I will be very happy if someone can help me with them.
1) I use 2 tubes 6550s in the power and I have a switch that allows to change the operation between triode mode and pentode mode. Do 6550s tubes go well in triode mode? Is there any risk in using triode mode? I ask this because I'm thinking of removing this switch that changes the modes.
2) The dirty and clean channels use halves of the first 12AX7, with half of the first triode for the dirty channel and the other half for the clean channel. As a way of connecting the 2 channels to the input, the builder connected the 2 grids of the triodes (check the photo). Is this a good solution? Is there any way to make this better? Is there a change in pitch or signal strength?
https://drive.google.com/file/d/1zSpgsI ... sp=sharing
These are some pictures of my amplifier's internal components. Do you have any suggestions for me? I want to get as close to a good Marshall sound as possible.
https://drive.google.com/file/d/1Hsou8I ... sp=sharing
https://drive.google.com/file/d/18WOXmv ... sp=sharing
https://drive.google.com/file/d/1e9U4Db ... sp=sharing
Thank you very much!
Kind regards,
Antonio.