Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: jerrydyer on August 25, 2018, 02:06:48 pm

Title: Marshall jmp 1H very low volume
Post by: jerrydyer on August 25, 2018, 02:06:48 pm
This thing is driving me crazy. Acts like bad O.T. had one so i swapped it. Same. Every single resistor is good. I have not checked every single cap. Just curious if there is already a known issue. I havent been here in a while. Im working for a service center that does repairs for so cal guitar centers. How you guys doin?
Title: Re: Marshall jmp 1H very low volume
Post by: Ritchie200 on August 25, 2018, 08:54:11 pm
Hey Jerry, good to see you back!

When you say acts like - Distorted output? No sound? Does the power mode switch still make a difference? Also check tension and clean speaker jack contacts.  I'm sure you did the tube wiggle to clean those up too.

Jim
Title: Re: Marshall jmp 1H very low volume
Post by: jerrydyer on August 25, 2018, 09:06:20 pm