#1
Hi everyone.
I have a technical one. I just bought a used Marshall EL84 20/20 power amp. Right now I have one 16-ohm cab, the second one is on the way, but it will take a week or two before it arrives. And I still have an 8-ohm cab. Both of them are wired mono.
I understand there has to be a cab connected to each output in order not to screw up the amp. BUT.... HERE COMES THE QUESTION: can I connect the 16 ohm cab to one channel and the 8 ohm cab to the other one? Each of the channels has a separate 8 ohm and a separate 16 ohm speaker outputs. I figure the sound will probably not be ideal in that configuration, but I just can´t watch my new amp silently resting in the rack for maybe two weeks without trying it out.... SO SCREW THE SOUND.... AND JUST TECHNICALLY: can I hurt the amp by connecting it like I mentioned above?

Thanks in advance for you replies!
B.C. Rich, Cort, Engl, Engl, Engl, Epiphone, Epiphone, Fender, Fender, Gallien-Krueger, Gallien-Krueger, Ibanez, Ibanez, Ibanez, KRK, KRK, KRK, Laney, Line6, Michael Kelly, Schecter, VHT, Yamaha....
Last edited by Airfish at Apr 17, 2014,
#2
yes you can, just make sure the ohms are set right for each channel
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#3
Quote by Robbgnarly
yes you can, just make sure the ohms are set right for each channel


there´s no impedance switch on the amp, just separate outputs with different impedances on each of the channels - so you say that if I plug the 16-ohm cab to the 16-ohm output of channel one and the 8-ohm cab to the 8-ohm output of channel two, this will not screw up the amp - CORRECT? Sorry, I better ask like an idiot, instead of sending my amp to hell....
B.C. Rich, Cort, Engl, Engl, Engl, Epiphone, Epiphone, Fender, Fender, Gallien-Krueger, Gallien-Krueger, Ibanez, Ibanez, Ibanez, KRK, KRK, KRK, Laney, Line6, Michael Kelly, Schecter, VHT, Yamaha....
Last edited by Airfish at Apr 17, 2014,
#4
Yes you will be fine

because your amp is stereo treat it like 2 separate amps not one.Just make sure if you only use one side do not turn the other side on. I am only familiar with the 100/100 but they all work on the same principals.
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#5
Quote by Robbgnarly
Yes you will be fine

because your amp is stereo treat it like 2 separate amps not one.Just make sure if you only use one side do not turn the other side on. I am only familiar with the 100/100 but they all work on the same principals.


Well that´s exactly one reason I´m asking: the amp has two inputs, two (pairs of) outputs, but both channels have the same power switch, stanby switch and level pot.... can it still by treated like two separat amps? is it just a matter of shared controls?
B.C. Rich, Cort, Engl, Engl, Engl, Epiphone, Epiphone, Fender, Fender, Gallien-Krueger, Gallien-Krueger, Ibanez, Ibanez, Ibanez, KRK, KRK, KRK, Laney, Line6, Michael Kelly, Schecter, VHT, Yamaha....
#6
Quote by Airfish
Well that´s exactly one reason I´m asking: the amp has two inputs, two (pairs of) outputs, but both channels have the same power switch, stanby switch and level pot.... can it still by treated like two separat amps? is it just a matter of shared controls?

That I'm not sure of, the 100/100 has separate switches I think, or my friend used his cab in stereo which is possible, but like I said I'm un certain. let some one more familiar answer that one. I don't want to **** your gear up on an assumption
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#7
Quote by Robbgnarly
That I'm not sure of, the 100/100 has separate switches I think, or my friend used his cab in stereo which is possible, but like I said I'm un certain. let some one more familiar answer that one. I don't want to **** your gear up on an assumption


That´s right, the 100/100 has everything completely separate, they even don´t call it a "stereo" amp but a "dual mono" amp.... and the question is, whether that´s just marketing crap or a matter of a technical difference....
But thank you anyway for your reply, I will either wait for someone else to give me a 100% answer, or loose my patience and take a risk - but without blaming you in case sh*t happens....
B.C. Rich, Cort, Engl, Engl, Engl, Epiphone, Epiphone, Fender, Fender, Gallien-Krueger, Gallien-Krueger, Ibanez, Ibanez, Ibanez, KRK, KRK, KRK, Laney, Line6, Michael Kelly, Schecter, VHT, Yamaha....
#8
Quote by Airfish
That´s right, the 100/100 has everything completely separate, they even don´t call it a "stereo" amp but a "dual mono" amp.... and the question is, whether that´s just marketing crap or a matter of a technical difference....
But thank you anyway for your reply, I will either wait for someone else to give me a 100% answer, or loose my patience and take a risk - but without blaming you in case sh*t happens....

If you do risk it (which I advise you wait to get a certain answer) you should be fine.
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#9
Quote by Robbgnarly
If you do risk it (which I advise you wait to get a certain answer) you should be fine.


Just kidding.... I WILL WAIT, hopefully not too long....

Gearheads the world of, your counsel seeking I am !!!!
B.C. Rich, Cort, Engl, Engl, Engl, Epiphone, Epiphone, Fender, Fender, Gallien-Krueger, Gallien-Krueger, Ibanez, Ibanez, Ibanez, KRK, KRK, KRK, Laney, Line6, Michael Kelly, Schecter, VHT, Yamaha....
#10
Rob's right. They are two independent amplifiers. Separate power tubes, separate output transformers (not just separate windings, actually two separate OT's), the lot. The only thing common to both sides is the power supply. They are essentially like two monoblocks in one box. As long as the load matches for each channel individually, no harm can happen.
So connect the 16 ohm cab to the 16 ohm output of one side and the 8 ohm cab to the 8 ohm output of the other side.
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Last edited by Cathbard at Apr 17, 2014,
#11
OK, so tried it out already and it really worked, without frying my amp! Of course the sound sucked, but I expected that, since the difference between the two cabs I used is a real big one (2x12 16ohm gtr cab & 4x10 8ohm bass cab). But at least I tried out the stereo fx in my board (reverb & delay) and they work just fine! So now I really can´t wait for my second 2x12 guitar cab to arrive! And the third stereo pedal I ordered (TCE Dreamscape)....

Thank you again guys for your advice!
B.C. Rich, Cort, Engl, Engl, Engl, Epiphone, Epiphone, Fender, Fender, Gallien-Krueger, Gallien-Krueger, Ibanez, Ibanez, Ibanez, KRK, KRK, KRK, Laney, Line6, Michael Kelly, Schecter, VHT, Yamaha....