Quote from: Bandito on February 14, 2025, 04:41:04 PMExcellent! I am East Devon, UK. Done the cleaning. The Amp works but sounds weak and different on channels 1/2 compared to 3/4.It should.
Channels 3-4 are Instrument (Guitar/Bass) level so more sensitive, 1-2 are high impedance Line level, think a Grammophone with a crystal/ceramic pickup, a radio tuner or tape recorder output, etc.
Any modern pedalboard would work fine there.
If you want to convert 1-2 to 3-4 specs, replace current 1M pots and 1M mixing resistors with 50k pots and 47k rtesistors, look at inputs in the schematic kindly provided by G1
QuoteHas 3 sockets for speakers. 1 and 2 (straight parallel connection) work, but the slave (3) does not.1 and 2 are regular speaker outs, 8 ohm impedance *total* so 16 ohm each if using both.

The 3rd one, clearly marked Slave, is NOT a speaker out but a Line out, meant to drive an extra power amp with its own speakers.
Old school design, not surprising in an early 70s amp.
QuoteIs this a "good" amp, worthy of investment?
You should ask your Financial Manager for that.
In my book, for a Musician, Amps (and Instruments and any Musical stuff) are either useful, good sounding, etc. or not.
I reserve the word "investment" for Tesla stock, gold, Bitcoin and similar stuff.
FWIW that amp is quite old style but very well made, working fine (except for some "cleaning" issues, of course) for 50 years now.