#1
Hey guys,

Me and the other guitarist from my band (Anti Icon) had a discussion about amp wiring earlier this week.

This is my situation:

I have a Peavey 6505 head and a Marshall 1960 A cabinet.
The Peavey has a switch to switch between 4ohm, 8ohm and 16ohm.
The Marshall cab has a switch between 4ohm, 8ohm and 16ohm aswell.
Now I'm not sure about the 4ohm part...but in the other cases I thought it was like this:

8ohm
Peavey is switched to 8ohm and the cab is switched to 8ohm as well
This is used to play stereo. When you only wire up 1 cable I'm just playing through 2 speakers, right?

16ohm
both are switched to 16ohm and now I just wire up 1 cable and I play through all 4 speakers. This is mono.


NOW, this is what the other guy thought:

When put on 16ohm, you just play through 2 speakers and the only way to play through 4 speakers is to switch to 8ohm and wire up 2 cables

WHICH IS THE CORRECT STATEMENT?

thx guys
#3
the marshall cab in stereo acts as 2 speakers per side, each 8 ohm total. so if you want to treat it as stereo, you'd set the impedance on the amp to 4 ohms, and run the 2 speaker outs to each 8 ohm input on the cab.

OR, set the head to 16 ohm, and run to the 16 ohm input (w/ the switch set to mono)

if you set the head to 8 and ran it to the marshall in stereo, you'd only be driving 2 speakers
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#4
You need to open it up to see what the ohmage on the speakers is, if each speaker is 4 ohms then it's probably like this

4 = 1 speaker
8 = 2 speakers
16 = 4 speaker

if the speakers are 8 ohms

4 = 2 speaker
8 = 4 speakers
16 = 2 speakers

if the speakers are 16 ohms

4 = 4 speakers
8 = 2 speakers
16 = 1 speaker

Now, I'm not 100 percent sure on that, it depends on how the cab is wired exactly, especially if all the speaker are 8 ohms since a cab with 4 8 ohm speakers with mono and stereo switches could be wired up many ways.

Your best bet is to take high resolution pictures and then use MS paint to mark + and - on the speaker terminals for us to see. Close ups of how the jacks are wired would help. You could also call marshall and see how they wire the cabs.
I don't give a shit if you listen to me or not
#5
Kevin the cab has a 4 ohm and 16 ohm imput for mono, and the inputs act as 8 ohm each when the stereo switch is engaged
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#6
So:


AMP.............................................CAB

__________________________________________

8ohm o-----------------------------------------o 8ohm

= 2 speakers
__________________________________________

16ohm o-----------------------------------------o 16ohm

= 4 speakers
__________________________________________


4 ohm o-----------------------------------------o 8 ohm
4 ohm o-----------------------------------------o 8 ohm

= 4 speaker (stereo)
__________________________________________


Is that about correct? Sorry but my english isn't that good...
Last edited by Kriptonite_r at Feb 9, 2009,
#7
Hmm, that's some strange wiring, but it probably has 16 ohm speakers and they are wired parrallel and and series. and then the are separately all wired in parallel for the 4 ohm (so in 4 ohms it uses all 4 speakers). At 16 ohms it would use all four as well, I forgot that you can wire up 4 16 ohm speakers to make a 16 ohm load. At 8 both inputs would use 2 speakers.
I don't give a shit if you listen to me or not
#8
Quote by Kriptonite_r
So:


AMP.............................................CAB

__________________________________________

8ohm o-----------------------------------------o 8ohm

= 2 speakers
__________________________________________

16ohm o-----------------------------------------o 16ohm

= 4 speakers
__________________________________________


4 ohm o-----------------------------------------o 8 ohm
4 ohm o-----------------------------------------o 8 ohm

= 4 speaker (stereo)
__________________________________________


Is that about correct? Sorry but my english isn't that good...


yup, that looks about right
Baron K2 SE 120
MILLS 4x12 Afterburner
Eventide TimeFactor Delays
ISP Pro Rack G Noise Suppressor
BKP Warpig pickups