GK MB500 Fusion B channel tone

[Si600]

I've noticed recently that when I switch my MB500 Fusion to the B channel the tone gets bassier and "muddier"  I've got the settings to the high side of "middley" but there's definitely a change when I switch between A and B.  B does have the gain (or whatever it should be called) nearly on full to deliberately get a crunch from it, effectively have a clean channel and a overdrive channel.  I may have completely misunderstood how to use the amp of course.

[Mudpup]

It's because you've switched the valves in.......it's supposed to make it a bit warmer (or muddier if you like) 😉

Edited June 5, 2018 by Mudpup

[Si600]

So I need to juggle the EQ controls to get a more consistent sound between the channels if I don't want such a big difference between them?

[Mudpup]

2 hours ago, Si600 said:

So I need to juggle the EQ controls to get a more consistent sound between the channels if I don't want such a big difference between them?

I had one and didn't notice a massive difference between the 2 channels EQ tbh - it was quite subtle. It was mainly the Gain that made a difference. Channel B was just a touch fatter and valvey sounding, Channel A was crisper.

[roman_sub]

When you are comparing, do you have gain and volume settings set exactly the same on both channels?

I thought it was the same circuit for both channels, but you could just control the amount of tube saturation via the gain control, changing the tone (and reduce / increase output volume accordingly)? Happy to be corrected though....

[Si600]

No I don't.  I'm using the A channel as clean and the B as overdrive so the gain settings are just under distorting on the A and almost to the stop on the B.  Volume controls are set so that there is no detectable difference in level when I switch between them.  What I do notice is that the B is bassier than the A.  I think I'm going to set it all back to the manual recommendations and start again, maybe with more crunch on my clean channel and make the B a bit more overdriven and sightly louder for solo infill.

I'm going to go back and reread the Confusing Menage a Troi thread, see if that helps.

Edited June 6, 2018 by Si600
Kant Spel

[roman_sub]

OK in that case I think what you are hearing is not difference in channel A/B voicings, rather it's the difference in how the tube preamp responds when higher level of signal (Gain) is put through it.  I think it's intended by design to let you have a cleaner and a dirtier sound via the two channels :-)

[roman_sub]

I suppose nothing stopping you from trying channel A as overdrive, and channel B as clean...

[Si600]

Well that was interesting!  I used it last night at our rehearsal session with a very quick setup, all the settings at 12 o'clock, both channel "gain" at half one-ish and the master "volume" very low so no-one died of internal bleeding and it sounded excellent.  I may tweak the settings a smidgen over the coming weeks but it's a good basis for something that I like the sound of.