Welcome to Solid State Guitar Amp Forum | DIY Guitar Amplifiers. Please login or sign up.

June 24, 2024, 12:16:52 AM

Login with username, password and session length

Recent Posts


McMartin Model LT252A

Started by RedMan81, November 24, 2015, 05:17:40 PM

Previous topic - Next topic


Good day people.  I have two questions I hope someone can help me with.   I was recently given a working McMartin Model LT252A page amplifier.  My questions are
1. Can the solid state tube replacements be converted back to tubes, and,
2. Will this amplifier work as a guitar amplifier?
I build guitars but I am not very experienced in building amplifiers.  I would like to get this into my guitar business, but I need  some expert advice.   That's for any help you can offer. :dbtu:


Solid state tube replacements?  I could be surprised of course, but I suspect if you see "tube sockets" with things plugged in, they are more likely transformers to match impedance.  If I am close, is "Line Trans" or "MIC trans" printed on the chassis next to the socket?  If you have some round things plugged into sockets, pull one out and read the label, what does it say on it?

Any amplifier can be used as a guitar amp, it is just a matter of what you need to do to it to make it work well.  Line inputs usually lack the gain for good guitar amps, but mic inputs often do have enough gain.

it would really help to have a schematic.

I have a McMartin LT-80B, and that was already transistor, by the time they got up to 252, they would not have gone back to tubes.


What Enzo said.  This is actually a 25W solid-state amp and would have been used as a PA in a hotel, factory, or etc.

Yes it should work as a guitar amp 'tho you might want to make some physical changes so you can plug in your guitar (and speaker) easily.

If you say theory and practice don't agree you haven't applied enough theory.


Or honestly, slap a distortion pedal in front of it.


Thanks for the input guys.  Like I said, I am new at this and need expert guidance.  I can find my way around a guitar blindfolded.  I  really enjoy repurposing things.  Again, thanks for the feedback and 8 know where to come for my next project.