# Any Owners of a CSA Marshall JCM 800 Model 4104 Combo?



## krall (Apr 19, 2009)

I have a speaker related question. I picked up an '83 CSA (Canadian export) Marshall JCM 800 model 4104 (2x12 50 watt combo) a little while back. It's currently loaded with a pair of new-ish Celestion G12T-75's (8 ohms). The amp originally came with a pair of Celestion G12-65's. I'm ready to post want ads for a pair of era correct G12-65's, but was wondering if Marshall originally put 8 ohm or 16 ohm Celestions in their CSA 2x12 combos. I'd like to know before I begin my search.

If any member on this forum has this model of amp with original speakers, can you relay to me what ohms they are?

Thanks.


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## cboutilier (Jan 12, 2016)

What impedence is stated on the amp?


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## krall (Apr 19, 2009)

cboutilier said:


> What impedence is stated on the amp?


It states 4 ohm minimum, but can easily switch to 8 ohms.


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## colchar (May 22, 2010)

I have the 2203 head, not the combo, and use it with a 2x21 loaded with G12-75 Creambacks and love that combination. Not that that matters for your purposes.


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## krall (Apr 19, 2009)

colchar said:


> 2x21 loaded.


Those are big ass speakers! lol


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## colchar (May 22, 2010)

krall said:


> Those are big ass speakers! lol



Nice catch. Damned typos!


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## BSTheTech (Sep 30, 2015)

Good luck finding the originals. It took me awhile to find mine. Ask for photos with the serial numbers. If they’re original they’ll probably be faded/hard to read.


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## Budda (May 29, 2007)

Given I sold an 80's JCM800 412 with those speakers for less than $500, you should be able to find the JCM800 212 cab with those speakers, and then just swap them.


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## krall (Apr 19, 2009)

I just found out that they were 8 ohms. Thanks!


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## gtrguy (Jul 6, 2006)

Regarding the G12-65 speakers- keep in mind there are a few different versions. I would avoid the versions with the 444 cones, those ones don't sound as good to me. Go for the 1777 cones.


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## krall (Apr 19, 2009)

gtrguy said:


> Regarding the G12-65 speakers- keep in mind there are a few different versions. I would avoid the versions with the 444 cones, those ones don't sound as good to me. Go for the 1777 cones.


Yeah, I already knew about the 1777 being the one to get.


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## jb welder (Sep 14, 2010)

krall said:


> I just found out that they were 8 ohms. Thanks!


Are you sure about this? That means you shouldn't plug in another cap while the internal speakers are in use (assuming it's wired for 4 ohm total).
Could someone have meant the pair is wired for a total of 8 ohms?


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## pckpat (Aug 19, 2009)

Back in the late 90's-2000's, I collected a few quads of the G12-65's that were used in the 80's JCM800 cabs and combos. The Canadian export versions were 8 ohms @ to comply with the CSA restriction that didn't allow the amps to be shipped/sold in Canada with the 16 ohm OT tap intact (on the premise that the amps would possibly catch fire at the higher impedance settings).


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## tdotrob (Feb 24, 2019)

All The CSA 2x12 I have seen definitley had 15 ohm 65’s and often came labelled as 130 watt but had g12m-70’s depending on the year. 

I just sold a couple pairs that came from 2x12’s and were all 15 ohm t3054 1777. 444 cones were bass cones for the 65’s in the 800 bass cabs and can be ok depending on the style of music you play but they get pretty flubby the louder the volume. 

800 lead series a and b 4x12 cabs that came with 65’s were 8 ohm in Canada. They are my favourite speaker with JCM series amps. Even better when paired with a couple of g12k-85’s in a 4x12. Finding the Rola 65’s nowadays is getting a little harder and a little more pricey.

Here are pics of the 15ohm t3054 1777 from 2x12’s and the 8ohm t3053 1777 for reference if you come across some. The heritage are just as good but a long break in period that sadly I think a lot of people never get past before selling them off.


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## tdotrob (Feb 24, 2019)

nevermind thread was two years old??


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## pckpat (Aug 19, 2009)

Thanks for the info Rob. That's good to know if I ever run across a JCM800-1936 cab, I'll try to grab it. I really like the old 65's too, that few dB lower efficiency doesn't hurt either. I have two or three left, and a couple of the K-85's as well. Guess I'll have to try pairing those two up in a box.


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## jb welder (Sep 14, 2010)

tdotrob said:


> All The CSA 2x12 I have seen definitley had 15 ohm 65’s and often came labelled as 130 watt but had g12m-70’s depending on the year.


That makes sense, a pair of 16ohm wired in parallel would be an 8 ohm cab so ok for the CSA versions. The 4x12 cabs would have used four 8 ohm speakers in series parallel for 8 ohm cab.
16ohm cabs or amps were not allowed in Canada at that time so the amps only had the 4 or 8 ohm settings on the impedance switch.


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## BobChuck (Jan 16, 2012)

jb welder said:


> 16ohm cabs or amps were not allowed in Canada at that time


Really?!? I'm curious to know why.


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## tdotrob (Feb 24, 2019)

pckpat said:


> Thanks for the info Rob. That's good to know if I ever run across a JCM800-1936 cab, I'll try to grab it. I really like the old 65's too, that few dB lower efficiency doesn't hurt either. I have two or three left, and a couple of the K-85's as well. Guess I'll have to try pairing those two up in a box.


make sure you check what’s inside instead of going off the badge. I bought a 1933 cab from a music store and asked if they were sure it had the original 65 in it, they assured it did and I didn’t feel it was necessary to make em take the back off being in a music store and all. Got it home and g12-70 which was the original speaker, but not the 65.Notorious Marshall switcheroo


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## keto (May 23, 2006)

@tdotrob that K speaker also makes an outstanding single speaker solution, in the right cab. Of all things I put one in a cheap Jet City 1X12, which had a lot of physical volume and sounded great, and it was perfect with both Marshall and Mesa Rectifier voiced amps, hundred watters. Obviously you had to be aware of limitations but, for the basement band thing, awesome sounding speaker. I lucked out, walked into Avenue Guitars about 8-9 years ago looking for one, and they had an old British one on the shelf at the old price lol.

Tight bottom like a V30, but not the mid push. Crisp never spikey up top.


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## tdotrob (Feb 24, 2019)

keto said:


> @tdotrob that K speaker also makes an outstanding single speaker solution, in the right cab. Of all things I put one in a cheap Jet City 1X12, which had a lot of physical volume and sounded great, and it was perfect with both Marshall and Mesa Rectifier voiced amps, hundred watters. Obviously you had to be aware of limitations but, for the basement band thing, awesome sounding speaker. I lucked out, walked into Avenue Guitars about 8-9 years ago looking for one, and they had an old British one on the shelf at the old price lol.
> 
> Tight bottom like a V30, but not the mid push. Crisp never spikey up top.


100% agree with all of that. I keep finding them in old peavey cabs people are trying to give away so it works.

I like them with the 65’s in an X keeps that jacked up mid of the 65and tightens the low end up nicely. When we get back to shows it’s def gonna be my go to 4x12 with my Landry, the Landry has an amazing mid heavy 4th gain stage and lots of treble that I use as a lead boost and it keeps the ice pick far away. I put one in another 1933 cab I have as well for when I just want to take the little guy around with my head to rehearsal or lower volume jams.


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## jb welder (Sep 14, 2010)

jb welder said:


> 16ohm cabs or amps were not allowed in Canada at that time so the amps only had the 4 or 8 ohm settings on the impedance switch.





BobChuck said:


> Really?!? I'm curious to know why.


Higher impedance speakers get more voltage and less current for a given wattage.
The explanation I was given was that, at the time, the user could be exposed to an unacceptable high voltage level via the output jack. If that is the true reason, the standards must have been relaxed since then.
In any case, the CSA JCM800 heads & combos did not have 16ohm settings and there were no 16ohm cabs available.


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