Jumping Channels on Fender Amps

[Mikoo69]

I have a vintage 1966 Fender Bassman head. I have heard about jumping channels on these (plug into input 1 of normal channel, cable out of input 2 into input 1 of second channel).

 

What are the benefits of doing this?

 

Does channel 2 act as a master volume?

[MattACaster]

You get the extra gain stage, low end and depp switch of the bass channel and the high end of the guitar channel. Sounds much better than running one at a time.

[BrainChild]

Typically on Fenders when you plug into both inputs of one channel there is a cut in the input to that channel, so you don't get much extra boost from using it. The channel doesn't really add a gain stage in series but another stage in parallel which increases gain minimally. It never gave me much worth doing it. 4 input Marshalls respond alot better to it. What I have done on Fenders is rodded them so the output of Channel 1 is fed into Channel 2 so the gain is in series. A decent tech can do this mod. They also used to make a device called an Ice Cube that you could put on Fenders that have reverb that allows that stage to add gain. A poor mans method was an RCA jumper but you get some screeching if you dial up the reverb too much. The best method is to just buy a good distortion box as Fenders take them well and there are so many nice ones now days.

[gtrjones]

 

Typically on Fenders when you plug into both inputs of one channel there is a cut in the input to that channel, so you don't get much extra boost from using it. The channel doesn't really add a gain stage in series but another stage in parallel which increases gain minimally. It never gave me much worth doing it. 4 input Marshalls respond alot better to it. What I have done on Fenders is rodded them so the output of Channel 1 is fed into Channel 2 so the gain is in series. A decent tech can do this mod. They also used to make a device called an Ice Cube that you could put on Fenders that have reverb that allows that stage to add gain. A poor mans method was an RCA jumper but you get some screeching if you dial up the reverb too much. The best method is to just buy a good distortion box as Fenders take them well and there are so many nice ones now days.

 

 

 

I *think* the reason that you get a small loss in volume is that on Fenders with Reverb, the 2 'channels' are out of phase. That's not the case with the bassman, 'cause it doesn't have a reverb circuit.

[newholland]

yeah-- i've heard jumpered bassmen sound outright amazing. if you've got a reverb channel-- you can probably just make a 'reverse' cable by flipping the ring and sleeve on a short 1/4" to 1/4" cable on one side. instant IN phase.

[Dolf]

Do it. Always do it.

 

Not jumpering the channels on a bassman is a sin. A sin punishable by death.

 

guitar into input 1 of the "normal" channel.

 

input 2 jumpered to input 1 of the "bright" channel.

 

 

INSTANT WIN.

[Mikoo69]

I have a vanamps solemate/reverb mate. it has the option for wet dry outputs or a blended output. should that just go at the end of my chain before it hits input one, or should i put it in between the inputs in the jumpered chain? also same goes for an EQ pedal?

[strtdv]

 

I *think* the reason that you get a small loss in volume is that on Fenders with Reverb, the 2 'channels' are out of phase. That's not the case with the bassman, 'cause it doesn't have a reverb circuit.

 

 

This is correct.

 

If the amp has reverb on channel 2, forget it unless you have a phase reverser, but if it doesn't, it's like jumpering the inputs on a Marshall or Hiwatt.

[the_bleeding]

Jumping channels sounds awesome. I built a sunn model t clone (its almost identical to a tweed bassman) and i always run both the channels at once. The normal channel is to dark on its own, and the bright channel is too fizzy. Combine them and its delicious.

 

 

 

Typically on Fenders when you plug into both inputs of one channel there is a cut in the input to that channel, so you don't get much extra boost from using it. The channel doesn't really add a gain stage in series but another stage in parallel which increases gain minimally. It never gave me much worth doing it. 4 input Marshalls respond alot better to it. What I have done on Fenders is rodded them so the output of Channel 1 is fed into Channel 2 so the gain is in series. A decent tech can do this mod. They also used to make a device called an Ice Cube that you could put on Fenders that have reverb that allows that stage to add gain. A poor mans method was an RCA jumper but you get some screeching if you dial up the reverb too much. The best method is to just buy a good distortion box as Fenders take them well and there are so many nice ones now days.

 

 

Uhm. Not quite. Parallel gain stages give you MORE gain than cascaded gain stages, but less distortion.

 

Think of it. JCM800 is input stage --> less powerful secondary stage, because in cascading amps, too much gain sounds like overdistorted crap. So in cascading, less gain can be used while attaining more dirt.

 

Bassman has 2 input stages, both of which have more gain than the jcm800 secondary stage. So it has more gain, but less dirt.

 

If you cascade a superlead or bassman, you'll notice that it will probably get a lot dirtier than your regular jcm800 because of the jcm800's compensation on the second gainstage to reduce gain and reduce feedback. Thats why the randy rhoads superlead is SO distorted, it uses 2 input stages as gainstages.

[Mikoo69]

how should i hook up the vansamp if i am jumping channels?

 

with the van amps i can have the dry output go to the bass channel and the wet channel go to the normal channel? is that the same as jumping, and also give me control of blend of verb?

[MattACaster]

I would just runt the guitar into the Vansamp and them run that into input 1 of the Bass channel. Then take another cable and run it from input 2 of the Bass channel into input 1 of the Guitar channel.

[Belva]

Add an A/B/Y box when jumping a bassman. You get many sounds on the fly if you set things up correctly. I know a guy who does this. All he uses is the Bassman, an A/B/Y and old Fender reverb unit. This b@$t@%d wails!

[Mikoo69]

how would i set that up?

[akapuli]

To me jumping channels on Silver-/Blackface Fenders is not very pleasant sounding.

[[VictorinoX]]

 

To me jumping channels on Silver-/Blackface Fenders is not very pleasant sounding.

 

 

It sounds REALLY good on old tweeds, like the Bassman.

 

If I'm not mistaken, most silver/black-face Fenders have a reverb channel, and trying to jump both channels doesn't really work with it.

[MattACaster]

 

To me jumping channels on Silver-/Blackface Fenders is not very pleasant sounding.

 

 

 

Sounds awesome on mine. Hell, a buddy of mine has his jumped internally. Same thing Mike Ness does, I believe.