Marshall 2204 Ohming confusion

[WhoFan]

Ok..... i have on old early 80's 2204 800 head..... I have a Marshall amp handbook from 1987 that has details on the complete line... The book is like an owners manual.... it came with a SS Marshall i bought in 87....

My 2204 has a switch for 8 and 4 ohm loads....

the handbook from a little later in the 80's says that the 2204 can be used with 4 8 and 16 ohm cabs.... it also says the 80's 1960A cab is 16 ohm

Did they change the 2204 ohmage selector later on in the 80's to 4 8 and 16 or would the later models have the 4 and 8 selection like on my 1982-ish model...?

I have a 5150 4x12 that is 16 ohms... i'd love to use the 2204 with it with a matched load but i can't see that happening.... oneday i want a Marshall cab as well but in due time...

Marshall ohmage selectors and the 1960 cabs confuse the heck out of me..

 

[jeremy]

Re: Marshall 2204 Ohming confusion

on new style marshalls you can run the whole cab at 16 ohms or 4 ohms or split each side (two speakers) at 8 ohms.

you can probably mismatch the 16 ohm cab with the 8 ohm output and as long as your arent running the amp full tilt you shouldnt have any problems.

i cant help ya as far as the change in impedance selectors but im pretty sure that ive seen some 2204 models with the three option switch

 

[ErikH]

Re: Marshall 2204 Ohming confusion

Is yours a Canadian model or US model? I believe that is where the difference is. US models having all three options and Canadian models having just the two, but the manuals remaining the same for both countries.

 

[Simon_F]

Re: Marshall 2204 Ohming confusion

Did they change the 2204 ohmage selector later on in the 80's to 4 8 and 16 or would the later models have the 4 and 8 selection like on my 1982-ish model...?

My '77 JMP 2204 and '87 2553 Jubilee both have selectors for 4, 8 and 16 ohms. I don't understand why a Marshall head wouldn't have a 16 ohm setting, as most 4x12s are 16 ohms. I'm confused too!

 

[Rich_S]

Re: Marshall 2204 Ohming confusion

I thought we discussed this recently....

Apparently, the Canadian amps only had 4 and 8 ohm selections. I know every JMP and JCM amp I ever owned (4 in total) had 4, 8, and 16. Maybe CSA didn't like something about the switches they used, or the higher voltage at 16 ohms, or something.

I also seem to remember that the Canadian output transformer does not have a 16-ohm tap wire hanging unused inside the chassis? If it did, you could replace the switch easily enough.

I say, add a series/parallel switch to your Peavey cab. That would let you select 4 or 16 ohms on the cab, then run the Marshall at 4 and the PV at 16. Unless your 5150 can handle 4 ohms, too - then just rewire the cab for 4 and run everybody that way. PM me if you want some help with the wiring details.

 

[WhoFan]

Re: Marshall 2204 Ohming confusion

ya i have the Canadian issue 800.... The one with the metal toggle on/off and standby switches.... I've been told by a few techs that the Canadian version is the one to own for whatever reason.. No real circuit difference i'm told but inside there was a few differences..

I don't what to rewire the 5150 cab.... I use it with the 5150 all the time.. don't want to mess with that set up..

I have no idea why they would not include a 16ohm selection on the amp...

 

[WhoFan]

Re: Marshall 2204 Ohming confusion

Hey Jeff i see ya lurkin.... any ideas....?

 

[Rich_S]

Re: Marshall 2204 Ohming confusion

I don't what to rewire the 5150 cab.... I use it with the 5150 all the time.. don't want to mess with that set up..

So, your 5150 head does not have a 4-ohm setting?

Adding the 4/16 selector to the cab is a simple mod, and it'll let you use the cab with either head. All it takes is a single DPDT toggle switch, and the wiring should take under an hour. It's the best solution.

 

[ErikH]

Re: Marshall 2204 Ohming confusion

The reason for no 16-ohm tap had to do with CSA regulations, much like the UL in the States. Coincidentally, the "standard" 1960A/B cabs sold new in Canada at the time were 8-ohms where as the same cabs sold in the U.S. were 16-ohms.

 

[WhoFan]

Re: Marshall 2204 Ohming confusion

The reason for no 16-ohm tap had to do with CSA regulations, much like the UL in the States. Coincidentally, the "standard" 1960A/B cabs sold new in Canada at the time were 8-ohms where as the same cabs sold in the U.S. were 16-ohms.

ya i was thinking that must be the case... Strange beast this Canadian 800 series eh!

 

[WhoFan]

Re: Marshall 2204 Ohming confusion

So, your 5150 head does not have a 4-ohm setting?

Adding the 4/16 selector to the cab is a simple mod, and it'll let you use the cab with either head. All it takes is a single DPDT toggle switch, and the wiring should take under an hour. It's the best solution.

yes the 5150 does 4,8,16..... doing that mod sounds cool but makes me wonder if it is just another thing to go wrong.... i'd hate to have the switch on 4 and the head on 16...

 

[Rich_S]

Re: Marshall 2204 Ohming confusion

yes the 5150 does 4,8,16..... doing that mod sounds cool but makes me wonder if it is just another thing to go wrong.... i'd hate to have the switch on 4 and the head on 16...

Actually, for tube amps it's worse the other way around: head on 4, cab on 16. If it was me, I'd rewire the cab for 4 ohms permanently, play the 2204, and leave the 5150 in a closet somewhere.

 

[krall]

Re: Marshall 2204 Ohming confusion

I have the same issue with mine (only 4 and 8 ohm selector)..I have a 1987 Canadian made JCM 800 (2210) with a toggle on/off switch, but a rocker for the standby and a square pilot light. The back panel of my Marshall is completely different from the UK/US models and came originally with EL34's...The best bet is to get a modern JCM 900 (1960) stereo cab, they have the 4-8-16 ohm selector in the back.

 

[WhoFan]

Re: Marshall 2204 Ohming confusion

I have the same issue with mine (only 4 and 8 ohm selector)..I have a 1987 Canadian made JCM 800 (2210) with a toggle on/off switch, but a rocker for the standby and a square pilot light. The back panel of my Marshall is completely different from the UK/US models and came originally with EL34's...The best bet is to get a modern JCM 900 (1960) stereo cab, they have the 4-8-16 ohm selector in the back.

i'll for sure keep my eye out for the 900 series cabs

 

[WhoFan]

Re: Marshall 2204 Ohming confusion

Actually, for tube amps it's worse the other way around: head on 4, cab on 16. If it was me, I'd rewire the cab for 4 ohms permanently, play the 2204, and leave the 5150 in a closet somewhere.

the 5150 is one of my favourite gigging amps... the only reason it is unused right now is it is too loud for home use... I need to get my arse in a band again soon..