Talk to me about jumper-ing amps

gripweed

Jolvisologist
What kind of amps can you do this with? How do you jumper an amp? Can you harm an amp by jumping it? Is more gain the only reason you would do this?
 
Re: Talk to me about jumper-ing amps

Are you talking about jumpering the two inputs....like on a Plexi?
 
Re: Talk to me about jumper-ing amps

if thats what you are talking about you cant really hurt anything, people do it all the time. not all amps sound better that way.

tweed fender and marshalls work fine, jump the channels and you get a fatter tone with more gain. try that on a fender amp with reverb and it wont work so well since the channels are out of phase with each other
 
Re: Talk to me about jumper-ing amps

ditto jumping two BF/SF Fenders---the inputs get padded down.
 
Re: Talk to me about jumper-ing amps

jeremy said:
if thats what you are talking about you cant really hurt anything, people do it all the time. not all amps sound better that way.

tweed fender and marshalls work fine, jump the channels and you get a fatter tone with more gain. try that on a fender amp with reverb and it wont work so well since the channels are out of phase with each other

Yep that is what I'm talking about. How do I go about doing that?
 
Re: Talk to me about jumper-ing amps

Take a small patch cable and connect it from input two (bottom) of the first channel to input one (top) on the second channel (so the cable goes diagonal). Then you plug ure guitar into the top input of channel one. You can do this the other way around too for different sound options also.
 
Re: Talk to me about jumper-ing amps

I highly recommend doing it on Marshalls
You can balance the tone so you get ballsy low end, and a balanced tone that still cuts. If you set the controls around 4 - 5 on the Vol, you can make it break up and clean up really nice when you back off. Add pedals to get more gain.

Otherwise, the BRIGHT channel or CH 1 on a Plexi style amp is really bright.

Boutique Amps like the Mojave and some Roccafortes jumper the channels for you so you just mix the volumes to taste and rock out.
 
Re: Talk to me about jumper-ing amps

And, with those types of amps, you can daisy chain them together. Input 2 of amp A goes to input 1 of amp B.

Another trick is to jumper the inputs on an amp with a reverb pedal like the Holy Grail, in between the two channels. Then, when you bring up volume II, you're mixing in some lows with reverb. It's the perfect way to add reverb to a plexi or bassman, while still retaining a punchy direct sound, since your guitar is plugged straight in to the #1 input....with no reverb.
 
Re: Talk to me about jumper-ing amps

Gearjoneser said:
And, with those types of amps, you can daisy chain them together. Input 2 of amp A goes to input 1 of amp B.

Another trick is to jumper the inputs on an amp with a reverb pedal like the Holy Grail, in between the two channels. Then, when you bring up volume II, you're mixing in some lows with reverb. It's the perfect way to add reverb to a plexi or bassman, while still retaining a punchy direct sound, since your guitar is plugged straight in to the #1 input....with no reverb.

While I have been jumping channels for years on bassman and marshalls (Edana since picked up), I never tried this method, until today.

Thanks for the really nice tip!
 
Re: Talk to me about jumper-ing amps

I'm glad that info could be of use to you. The first time I tried it, I tripped out because it solves the problem of no reverb or FX loops on those vintage amps.
And best of all, you can mix the reverb with the reverb unit's output knob and the Volume II on the amp.
 
Re: Talk to me about jumper-ing amps

ive been doing just that on my tweed amps, plugging into bright 1, running bright 2 into the rev unit and back into normal 1.

ive recently modified my plan of attack slightly

i plug into an A/B box- A goes to the reverb and into the bright channel with the volume at 5, B goes to the normal channel with the volume on 9 or 10.
that gives me a nice cleaner tone with reverb and a dirty tone without or with both channels on i get a fatter dirty tone with reverb. still cleans up nice when you roll the volume back
 
Re: Talk to me about jumper-ing amps

Does this work on an amp like the reissue '65 Twin? Would that enable it to have a pseudo effects loop?
 
Re: Talk to me about jumper-ing amps

The problem with BF/SF reverb amps is that the 2 channels are 180 degrees out of phase respective to each other, so;
1. yes it will work, but...
2. it may not sound very good.

Of course, the less of the signal that gets mixed in, the less phase cancellation, so a very wet signal at low levels might work just fine...
 
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Re: Talk to me about jumper-ing amps

Gearjoneser said:
And, with those types of amps, you can daisy chain them together. Input 2 of amp A goes to input 1 of amp B.

Another trick is to jumper the inputs on an amp with a reverb pedal like the Holy Grail, in between the two channels. Then, when you bring up volume II, you're mixing in some lows with reverb. It's the perfect way to add reverb to a plexi or bassman, while still retaining a punchy direct sound, since your guitar is plugged straight in to the #1 input....with no reverb.
well...since i've never had more than one amp at a time i've never thought about this stuff before...i'll definitely file this away in my brain for future use!

i hope this is not a hijack- but since i've also never had anything but a one channel type amp before, what's the specifics on the hi-lo inputs and bright channels and etc?
 
Re: Talk to me about jumper-ing amps

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Reverse the patch cables too for an interesting tone...(bridge top left & lower right....plug into top right)...sounds cool with single coils :wink:
 
Re: Talk to me about jumper-ing amps

Hey how does the input pad work on Fender circuits? Of the two inputs (same channel) the first one is "higher gain" and the second one is padded down. So if you use the second one to daisy chain to channel 2, is that signal padded? Since everything is parallel wired, does it also pad input A? Does it pad inputs A/a of channel 1 but then still send an "unpadded" signal to channel 2, which you can then decide if you want padded or not? If you go to channel 2, input b is that "double padded"? And finally, does that pad diminish the signal at all? Should we be removing the pad if we're going to jump the channels? I'm thinking of it like this:

Channel 1= A a
Channel 2= B b

So what happens when you chain them?

C1= a a C2= B
C1= a a C2= b
C1= A a C2= B
C1= A a C2= b

I think I knew all this stuff a decade ago but my brain filed it under "You're an idiot, who can't remember what he's had for lunch today, so why would you think you could remember all of this?"
 
Re: Talk to me about jumper-ing amps

Yeah, the problem with most Fender Blackface type amps is that the 2 channels are 180% out of phase, plus they already have reverb, so there's no real point.

Then, on amps with a hi input and lo input, the 2nd input is padded, so if you daisy chain that to something else, it'll be a little murky sounding.
These types of amps aren't really good for bridging channels (with or without reverb), because both inputs share 1 channel.......there's no point.

The amps that benefit are the 4 input plexi, bassman, AC-30 type amps with 2 non-channel switching sides.....with a volume on each. You're basically just mixing the bassy channel with the bright channel, to create the right tone.
 
Re: Talk to me about jumper-ing amps

Joe,

What if you were to use a rackmount unit in between the channels on a Marshall as a pseudo loop for REVERB, CHORUS, and DELAYS?
 
Re: Talk to me about jumper-ing amps

OlinMusic said:
Joe,

What if you were to use a rackmount unit in between the channels on a Marshall as a pseudo loop for REVERB, CHORUS, and DELAYS?

There might be an impedence or db difference, but some rack gear has +4 -4 buttons, so maybe it'll match. You should try it and report back.
 
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