Need advice hooking up my Amp Selector stomp box.....

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pm999
Posts: 5
Joined: Tue Nov 03, 2009 1:02 am

Need advice hooking up my Amp Selector stomp box.....

Post by pm999 » Tue Nov 03, 2009 4:12 am

Hi there Voodoo guys & gals....this is my first post.
I recently bought a Voodoo Lab Amp Selector so that I can hook up my two Marshall heads to my one 1960a cab and be able to switch between them at the press of a button and also to enable me to play both simultaneously and blend the two tones (one is KT66 based the other EL34).
My question is regarding the ohm setting on my amp heads. My cab is a standard 4x12 16ohm cab so both heads have ohm selector set on 16 when played individually.
But, when I hook both the heads to the Amp selector and both are switched on what should the ohm setting be on each head (for individual use not simultaneous)?
Furthermore, do I need to change the ohm selector if I play both amps together simultaneously? What load are the heads seeing thru the Voodoo Lab amp selector?
I've got loads more questions (all related to this) but I guess this'll be a good start.
8-)
Thanks.

JohnClark
Posts: 7121
Joined: Tue May 05, 2009 2:33 pm
Location: The Lab

Re: Need advice hooking up my Amp Selector stomp box.....

Post by JohnClark » Tue Nov 03, 2009 10:49 am

Do not connect the speaker outputs to the Amp Selector! This will damage the Amp Selector and quite possibly the amplifiers.
The Amp Selector is intended to accept a guitar signal and switch/split it to the selected amplifier inputs. You will still need two cabinets with this particular setup.

http://www.voodoolab.com/manuals/as_manual.pdf

pm999
Posts: 5
Joined: Tue Nov 03, 2009 1:02 am

Re: Need advice hooking up my Amp Selector stomp box.....

Post by pm999 » Tue Nov 03, 2009 12:33 pm

I get it (......I think.....),
So, my cab stays connected directly to my amp head as normal and the Amp Selector directly to the input of the amp (where the guitar would normally plug into). Then I plug my guitar into the amp selector.... Got it.
And in order to be able to switch between my amps I'll need a second cab to plug my second head into.....This'll then allow me to switch between each amp/cab unit as well as playing both sets together simultaneously and blending amps.....Got it.
I was overcomplicating it.
Is there anyway I can forego the second cab and have both amps plugged into my marshall cab (there are two inputs in the back of the cab so I presume I would have to change the ohm selector to 8ohms on each head (as if running them in stereo)) and the amps into the Amp Selector so this way each amp would be driving a pair of speakers in the cab? and I could choose which amp to use from the Amp Selector?
Thanks JohnClark, much appreciated.

JohnClark
Posts: 7121
Joined: Tue May 05, 2009 2:33 pm
Location: The Lab

Re: Need advice hooking up my Amp Selector stomp box.....

Post by JohnClark » Tue Nov 03, 2009 4:21 pm

If the cabinet is in fact wired for stereo then this should work as described. For instance, if the two jacks on the cabinet are marked as separate 8 Ohm loads, then yes, the two amps would each be set to 8 Ohms. I think it would be best if you talked to someone at Marshall while armed with specific model numbers of the amps and cabinet in question if the exterior markings are not clear enough to provide an answer.

pm999
Posts: 5
Joined: Tue Nov 03, 2009 1:02 am

Re: Need advice hooking up my Amp Selector stomp box.....

Post by pm999 » Wed Nov 04, 2009 5:31 am

Kind thanks, JohnClark, much appreciated. I already have downloaded the schematic for speaker wiring in a typical 1960a cab (which also allows for 8ohm stereo use). I'll take the back off and check the wiring (I had actually done it long time ago when I * my four G12H's but I can't remember if I followed exactly as it was stock or if I changed it only for 16ohm operation and I really don't wanna burn out my Silver Jub. or modded 1987x.
Thanks again.
:D

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