Im sure this is a silly question but I am a noob when it comes to cabs. I never really had to worry about this in the past. So I just bought a brand new Peavey 6505+ and a new yet used Marshall JCM 900 1960A cab, and the connections on the back are not as straight forward as they are on my peavey cab. I want to make sure I do this correctly so I don't damage the head.
Here is a pic of the back of the cab and the settings on the 6505+.
How do I correctly connect the head for 1 cab use as well as 2 cabs for a full stack if I wanted too? And which ohm setting should be selected for both situations?
I also do not know what mono and stereo means? Is mono single cab and stereo 2 cabs?
Please if you can answer this, do so in idiot terms. lol
Thanks for any input...
I looked up the manual for the Marshall cab online and it says that in the mono setting the cab runs at 4 ohms from the right input. I would set the thing to mono and set my amp at 4 ohms and plug into the right input. Stereo seperates the cab into two halfs, 8 ohms for each set of two speakers. In mono you will be running all four speakers. It says if you select mono and use the left input the impedance is 16 ohms. If you used that jack you would set your head to 16 ohms. Make sense? Here is a link to the cabinets manual.
http://marshallamps.com/downloads/files/Cabs%20Hbk.pdf
For two cabs we would need to know the impedance of the Peavey cab. Your jacks on your head say they are paralled so if your Peavey cab was 16 ohms you would be set. You could run both cabs in the 16 ohm mode and when parralled the total resistance would be 8 ohms and you would use that setting on your head. This is confusing isn't it?
In either case, the switches on your Marshall cab are nothing to do with how many cabinets you run. They make the Marshall either two sets of two 8 ohm spearkers or four speakers that can be either 4 ohms or 16 ohms, depending on the switch position and the jack you plug into. Bottom line is your total resistance has to be between 4 ohms and 16 ohms and your amp switch has to match whatever it is.
"Work hard, rock hard, eat hard, sleep hard,
grow big, wear glasses if you need 'em."
-- The Webb Wilder Credo --
Thank you for the reply! I was actually discussing this on another forum and we came up with this info:
Head set to 4 Ohms, then use 1 speaker cable into the 4 Ohms switch on the left of the cab. Always set the cab to mono.
Head set to 16 Ohms, then use 1 speaker cable into the 16 Ohms switch on the right of the cab. Always set the cab to mono.
2 Speaker cables is over kill and if the switch on the cab is moved accidentally from mono to stereo then bad stuff can happen, so you are better off using the above info using only 1 speaker cable.
But the lefts and rights are reversed in the marshall info you linked to from what it looks like on the back of the amp. Is that because the right input on the back is really the left when viewing the amp from the front? I wanted to edit my post with the above info for anyone else with questions but it still wasn't approved...
It says in the manual, the right and left seem reversed because it is the left and right side as you look at it from in front of the cab.
"Work hard, rock hard, eat hard, sleep hard,
grow big, wear glasses if you need 'em."
-- The Webb Wilder Credo --
