Simulating a jumped amp

[brue58ski]

I'm not getting a straight answer from the internet. I want to simulate jumpering two amp inputs. It sounds like it's essentially the same as having the one guitar plugged into the two inputs so I would just need to use the  two amps in parallel to each other going into the same cab. Like the Vib an Nrm channels in a Twin Reverb. Can anyone confirm this?

[Schmalle]

Sort of. But not really. There are multiple ways to jumper amps which changes the input impedance in different ways. Using jumpered inputs on an amp means the guitar signal is split and runs in parallel through parts of the amp. Often that's two preamps and both signals are mixed before the power amp. There are some interactions - negligible or audible - that aren't there when you use two parallel amps. 

[brue58ski]

It's just something I was reading about in reference to the Deluxe Reverb. Yes, there are amps that are jumpered but they are mostly Marshalls, not the Fenders. I figured both inputs were mixed before the power amp but, as we all know, the Helix doesn't have separate power amps. Thank you all for your responses.

[Schmalle]

Besides the jumpered channels in the HX I'd recommend to try the Divided Duo - use Drive1 as a bright channel gain and Drive2 is a normal channel gain. A trick is to set Drive2 to 0, then choose the amount of gain you want with Drive1 and finally add Drive2 back to add body/fullness - pretty cool.

 

Also the Elmsley has the feel of an already dialed in jumpered amp.

[codamedia]

 

On 4/19/2024 at 7:10 AM, brue58ski said:

It's just something I was reading about in reference to the Deluxe Reverb.

Place two Deluxe Reverbs amps (without cabs) in parallel with each other. Have one block loaded with the normal channel, and the other loaded with the vib channel. Load the cabinet separately after the merge block so it is shared. Sure... that means the power amp is not shared but that's really not that important.  

 

On 4/19/2024 at 7:10 AM, brue58ski said:

Yes, there are amps that are jumpered but they are mostly Marshalls, not the Fenders.

 

There is a reason for that. On most real BF/SF Fenders the two channels are out of phase with each other....  that made them impractical to jump without modding one of the channels so it never was very common. Real Marshalls didn't have that same problem so the jumped sound became part of Marshall's history. 

[brue58ski]

On 4/22/2024 at 4:31 AM, codamedia said:

 

Place two Deluxe Reverbs amps (without cabs) in parallel with each other. Have one block loaded with the normal channel, and the other loaded with the vib channel. Load the cabinet separately after the merge block so it is shared. Sure... that means the power amp is not shared but that's really not that important.  

 

 

There is a reason for that. On most real BF/SF Fenders the two channels are out of phase with each other....  that made them impractical to jump without modding one of the channels so it never was very common. Real Marshalls didn't have that same problem so the jumped sound became part of Marshall's history. 

 

Yeah, there were articles talking about the out of phase thing but they mostly had certain tone knob settings that supposedly worked. It was those articles that got me interested in this pursuit.

[CraigGT]

The Normal channel of a Deluxe Reverb uses two triodes before the PI and the Vibrato channel uses three.

Every triode stage causes phase inversion and that is why the channels are out of phase and they don't jump well.