too much bass...

[mynameisjonas]

after a few more rehearsals with my sovtek mig50, i'm starting to get a bit annoyed by the massive amount of bottom end it has, even with the bass knob turned all the way down it's still huuuge, and it can be a bit overpowering when i switch on my distortion pedals.
is there a quick mod i could do, like change a few caps, or use different power tubes perhaps? it currently has sovtek 5881s in it, i'm thinking maybe i could use el34s instead, or would that require extensive mods?

[holy-reverb!!]

From EL34 to 5881 type would mean changing the output section in some way.
You could try different tubes from the same family, as the KT66 would change the sound the most with no mods. The KT66 and 5881 are both 25 watts approx, but the KT66 has a plate voltage of 500 volts and the 5881 of 400 volts.

I changed the power tubes in my friends  blues custom 30 from the sovtek 5881 to the new gold lion KT66 and its amazing how much it opened the amp up.

Before looking into the preamp section of your mig to change caps, look at the tubes. Changing various values will give some different EQ response.

[mynameisjonas]

thanks, i'll look into the KT66s

btw, that's what they use in JTM45s, right?

[Pacafeliz]

maybe it's the speakers? how does your cab behave with other amps, or vice versa?
rock on!

Pat.

ps: i'll send the MASS out as soon as i get a free minute; 2 jobs don't leave too much times. but i'll let ya know ASAP. 

[holy-reverb!!]

thanks, i'll look into the KT66s

btw, that's what they use in JTM45s, right?

Yes, the JTM45 and therefore the bluesbreaker.

And as pacafeliz said, the speakers could be the only problem. If you are using a 412, changing even two speakers to something like eminence screaming eagles could brighten it up the right amount. Maybe you should take the MIG to a store and try it with a cab with bright speakers, and see how it behaves. Tubes and speakers will make a much bigger difference that a few caps.

[hieronymous]

How about speaker placement? If you have it against a wall or in a corner it might be accentuating the bass frequencies. You might find that live on a stage it might be just right!

[øøøøøøø]

thanks, i'll look into the KT66s

btw, that's what they use in JTM45s, right?

Yes, the JTM45 and therefore the bluesbreaker.

And as pacafeliz said, the speakers could be the only problem. If you are using a 412, changing even two speakers to something like eminence screaming eagles could brighten it up the right amount. Maybe you should take the MIG to a store and try it with a cab with bright speakers, and see how it behaves. Tubes and speakers will make a much bigger difference that a few caps.

If you can find a schematic and post it here, I might be able to make some suggestions.

Cathode bypass caps are one thing you can look to change in your situation.  For instance, many guitar amps use 25µf cathode bypass caps and many bass amps use 50µf.  

[Orang Goreng]

Plucked off the web:

[øøøøøøø]

So, I bet the second input sounds really different from the first, right?

Is the cathode resistor of V1 really bypassed with a 220µf cap?  It's a little hard to tell for sure as that schematic is really small.  If so I'd try reducing that value... maybe by like half... and see what that sounds like.

[mjet]

Here's a detail of V1 and V2

[mynameisjonas]

it's definitely not the cab, i've had it for over 11 years, and it's never struck me as particularly bassy.

regarding the cathode bypass caps; that's one of the mods that has been done to the amp. both channels sound pretty much the same (channel 2 being just a tiny bit darker), and it has a switch that changes cathode bypass cap values. the switch doesn't make that much difference, so i think i'm gonna see if i can reverse the mod. as you said, there ought to be a pretty big difference between the two channels, that's what most of the reviews i've read on this amp say anyway.

thanks for the help

[GUITARmole]

The inputs should sound completely different...I'd put it back to stock and go from there.

[Professor Plum]

i might be crazy but JJ tubes tend to sound a little brighter to me, could go for those when you pickin up new tubes...

[øøøøøøø]

i might be crazy but JJ tubes tend to sound a little brighter to me, could go for those when you pickin up new tubes...

Odd.  Their 12AX7s are the darkest new production I've tried.

[mynameisjonas]

If the thing has been monkeyed with, it's obviously someone's "idea" of what they wanted, and your idea may not (does not) agree.

yeah, judging by the other mods, the person who did them obviously wanted a more gainy, metal sounding amp.