Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => The Newcomer's Forum => Topic started by: jjonas2 on May 22, 2024, 10:14:53 AM

Title: Marshall Mosfet Lead 100 boost channel pop
Post by: jjonas2 on May 22, 2024, 10:14:53 AM
Hi,

I have a Marshall Mosfet Lead 100 guitar amp (3210), and when I switch to the boost channel while playing, there's an audible pop (also if connected directly to a mixer from the DI in the back). The other way (boost->normal) there's no pop if I switch while playing. Also, normal->boost there's no pop if I'm not playing.

What I want to ask is, is this expected behaviour?
Title: Re: Marshall Mosfet Lead 100 boost channel pop
Post by: joecool85 on June 07, 2024, 04:45:27 PM
Without hearing it, I'm going to say that it is most likely normal for this to happen.  Channel switching can certainly cause noises on certain amps.
Title: Re: Marshall Mosfet Lead 100 boost channel pop
Post by: J M Fahey on August 11, 2024, 04:15:59 PM
Quote from: jjonas2 on May 22, 2024, 10:14:53 AMHi,

I have a Marshall Mosfet Lead 100 guitar amp (3210), and when I switch to the boost channel while playing, there's an audible pop (also if connected directly to a mixer from the DI in the back). The other way (boost->normal) there's no pop if I switch while playing. Also, normal->boost there's no pop if I'm not playing.

What I want to ask is, is this expected behaviour?
Quoting from faint memory, channel switching was crude, using plain old bipolar transistors instead of better FETs.

In such case there is not perfect isolation between switching pulse and Audio and feedthrough is possible.

No big deal, Marshall deemed it acceptable, so .....

That head was originally despised for being SS but now is respected.
It is a LOUD beast, that´s for sure  ;)