[GuitaristZ]

Ok, I have a marshall jcm2000 dsl50 head and a marshall 1960 cab. I find it very loud. Well, I found out today my cab has a thing called stereo mode or whatever, where I can use just 2 of the 4 speakers inside (I think?) so it will be less loud for practicing.

Here is the manual for my head: http://marshallamps.com/downloads/files/DSL100_50 hbk.pdf

Here is the manual for the cab:
http://marshallamps.com/downloads/files/Cabs Hbk.pdf

I want to know, if I can switch the cab to "stereo", plug in to either side of the cab (because both sides are 8ohms) and then plug the other end of the cable into my amp, which has selectable ohms to 8ohms. Will this screw up my amp or cab? I guess the question is, when I put the cab on stereo, I will be just hooked up to 2 speakers right? So I could use either side of the cab, without having to use all 4 speakers? they say in the manual that the stereo thing is for a "stereo power amp" so im not sure when in stereo mode, if you have to use both inputs or not. I know this is probably confusing, but I need help badly and will appreciate this VERY VRY VERY MUCH!!!! Thanks!!

 

[GuitaristZ]

This is what I want to do:

I just need to know if this is safe to do. thanks!
btw, I usually just use "mono" mode and plug the only cord I have into the 16ohm output on head, and then into the 16ohm input on cab. However since this uses all four speakers...you can imagine how loud it is for practicing...I cant get the volume past 2.

Edit:
I emailed marshall and I will get a response probably tomorrow. I think this should be made a sticky after I get a definite response from marshall because it seems not many people know as it is not clearly laid out in the manual.

also, please respond only if you know for sure...I spent my entire summer jobs wages (2300$) on this amp and cab and dont want to damage it.

 

[Wild Bill]

In MONO mode you go by the top set of labels. The jack on the left shows a 4 ohm load. The one on the right will give 16 ohms. All 4 speakers are working.

In STEREO mode you use the bottom labels. Both sides offer 2 speakers that show an 8 ohm load.

For optimimum power you set things at the amp to the right ohm setting for the speaker load. So if you are running in STEREO with 8 ohms then set the amp for 8 ohms.

In practice the amp will handle a mismatch without noticeable harm. If you forget to change things at the amp when you switched from mono to stereo don't worry about it. The tone will change slightly (you probably won't even notice) and the power tubes will wear out a month or two sooner if you ran things with the mistake at full power for a year's worth of weekend gigs!

It's important to have the amp and speaker load settings matched but it's not THAT important!

Just don't play any ABBA tunes and things will be fine...

 

[GuitaristZ]

So I can use the stereo mode and just use one of the inputs? (8ohm). I thought at first I had to use both of the inputs in stereo mode which I didnt want becaues I just wanted to use 2 speakers.

 

[Wild Bill]

"Just the same, only different!"

So I can use the stereo mode and just use one of the inputs? (8ohm). I thought at first I had to use both of the inputs in stereo mode which I didnt want becaues I just wanted to use 2 speakers.

Nope! Just use one and don't connect to the other one at all.

In stereo mode just think of your cab as two 2-12 separate cabs. Use one or use the other.

It's sorta like a townhouse - two different houses with some common walls.

 

[GuitaristZ]

Thank you for your help dude! You have spared my ears a lot of pain lol...

so this isnt going to hurt my amp at all right? what if I used this setup live? any problems with that you think?