"original" 18 watt on the bench

[Madison]

Hey guys.

Got an original 18 watt here with 2x10s.

I am sure this thing has been gutted and messed with like crazy.
I am almost certain the answer in "no" on this but did an 18 watt ever come with ECL86 power tubes?

It just doesn't seem to have the power it should.
I'd like to talk the guy into gutting it and let me do it "right"

Don't know much more about it.
Serial number on the back panel is 8570.
It has some sort of "boost" mini switch on the front panel.
Celestions stamped 7442.

Sorry, no decent camera in hand at the moment.
Any info would be great.

Peace

[jazbo8]

Some pictures.

ECL86 is a triode/pentode, how can it replace the EL84? Is the ECC83 for the PI replaced as well? It's a shame that someone would butcher a classic like this...

[DummyLoad]

i can't recall any marshall schematic i've seen that uses ECL86 except for one and that's used for reverb drive & recovery in the specialist model 2046.  


http://www.el34world.com/charts/Schematics/files/marshall/jmp_specialist_25w_2046.pdf

--pete

[echuta13]

That's a pretty uncommon bird I suspect...  Sounds like it's a Marshall 1930.  Maybe like this?  http://www.chambonino.com/work/work11.html

[Geezer]

That's a pretty uncommon bird I suspect...  Sounds like it's a Marshall 1930.  Maybe like this?  http://www.chambonino.com/work/work11.html

Ha, better not gut it, I guess.....might be a valuable little amp (at least someday in the future)

[sluckey]

That's a pretty uncommon bird I suspect...  Sounds like it's a Marshall 1930.

I agree. Here's the schematic...

       http://www.el34world.com/charts/Schematics/files/marshall/jmp_1930_10w.pdf

Don't gut it! Verify what you have.

[Madison]

I'll go back to the studio tomorrow and try to get better pics.

The speakers are like that single that was left in that 1930 story.

The cabinet is a regular 18 watt.

Here are the couple of crap photos I got when I was there.
Even in these pics you can see, a lot of stuff has definitely been changed.
(The factory red paint on the tops of the solder points were all about gone.The solder job looks like crap BTW)
There is an addition of a terminal strip to the circuit board for the mini switch mod.

The owner doesn't care at all if I gut the board but I personally will try to get some more info on it.
Maybe..........a really rare one.
I know he paid takusan/mucho/a lot of yen for it.
I got to play his '59 Les Paul through it :)

Peace

[Madison]

another

[Madison]

More I look at it.
Since it only has 2 preamp tubes, I ain't changing it!
I surely am not about to punch another hole in that chassis for a preamp tube!

Maybe some caps and tubes, but that's about it.
Pretty bizarre interesting amp for sure.

[DummyLoad]

looks like it's been hacked on. perhaps you should restore it?

i definitely wouldn't hack on the chassis. popular or not, it's seems rare enough to have possible collector value?

--pete

some more info on it...

http://www.chambonino.com/work/work11.html

[Madison]

The owner will go for it but I don;t want any regrets later.

I wrote directly to Marshall to see if they have any info on this amp.
Don't know if they answer this sort of thing.

Thanks.
Peace.

[Ritchie200]

Good luck....  I've written (via email and post) them on several occasions on my Majors and crickets were all I heard.  They were legit questions about repair and replacement.  I did write another about Ritchie Blackmore and his Major and got the same response!  The only time I was able to talk to someone at Marshall was in 1978 or 79 after I lost a tranny in my Major.  It took them about 3 months to get me a new one.  The old St. Louis Music, Carvin, and Peavey are the only people I have had luck with in the past few years.

Cool amp.  I would put it back original and see how it sounds.  He might be more impressed with that than with the mods that have been done.  You can always put them back in.

Jim

[smackoj]

I was reading through some stomp box designs over at runoffgroove.com and found this tidbit of info on the Marshall 18 watters; if this combo has 2x10, then according to this article, it would be a model 1958.

excerpt from runoffgroove website:  "Around 1965, Marshall introduced a few amps built around an 18 Watt EL84 powered circuit. While these models were intended for practice, the sound was much better than other small amps. Unfortunately, only a few hundred of these combos were manufactured over the next three years. These rare amps were given the model numbers 1958 for the 2X10" combo, 1973 for the 2X12" combo, and 1974 for the 1X12" version.

The features were two channels with Volume and a single Tone on each, along with Tremolo on one channel and an optional Reverb. The 18W amps consisted of 3 12AX7 type tubes and a pair of EL84 power tubes in push-pull configuration. Legend says Jim Marshall bought the circuit from Watkins Electric Music. Watkins sold a very similar amp they called the "Watkins Dominator."

 

[DummyLoad]

 if this combo has 2x10, then according to this article, it would be a model 1958.

has already been established this a very rare marshall model 1930 that uses 2 x ECL86

http://www.el34world.com/charts/Schematics/files/marshall/jmp_1930_10w.pdf

http://www.chambonino.com/work/work11.html

[JB]

It's the 1930 2 x ECL86 model, not one of the 18W family. I had one of these when I was a teenager, my first amp!  Didn't know what I had and sold it for what I paid for it.  Regretted it ever since!  We live and learn.

Mine looked original inside but the tremelo was faulty - loud thumping noise, and the amp was generally noisy.  If I had it now I could fix it - didn't have the knowledge/skills back then.

 

[smackoj]

I stand (actually sit) corrected. The model 1930 "Capri" amp. Way huge, way cool, and appears to be Way Rare!  I'd rename it the
'Capone' in honor of 1930's prohibition, the moon shiners and the kingpin of the era, Big Al.   

Can you tell who made the transformers Madison?

Jack D

[echuta13]

Actually I think this is what they call the "Popular".  The Capri is another odd one... 

[Madison]

I have not been back to the studio yet.

What I want to remind everyone is, this thing ONLY has 2 preamp tubes.

Did I like the tone, not really but.......I haven't played it enough.
I was expecting an 18 watt tone!........until I understood what was happening under the hood.

I'll get back to it this week and give some better info if I can.
I need a better camera.
Just moved and a lot of things are here and there.

I know it is a crazy rare amp.
This guy has a great collection of stuff.

BTW Jim, he has all the original Rockman stuff!
Gawd, Sound great too!!

[sluckey]

What I want to remind everyone is, this thing ONLY has 2 preamp tubes.

That's one more than the 1930 has. The 1930 only has 3 tubes, one 12AX7 and two ECC86s. And the board in your amp looks very different from the board in a 1930. You may have to draw a schematic to tell what you really have. I'd be surprised if it matches any stock Marshall amps. I think you have a very special amp... or, a very big hack.

Does the tremolo work?

Do I see a 7 lug terminal strip mounted on the board???

[jazbo8]

Found this at drtube:

In 1965 Marshall introduced the 18W "practice" combo amps. Although they were not very loud, they certainly could "rock". There were originally 3 combo models: 1958, 1973 and 1974. They had a tremolo and an optional reverb. These amps used two EL84 tubes in the power amp, three ECC83's in the pre amp and an EZ81 rectifier in the power supply. If the reverb was fitted, an ECL86 was used as the reverb drive/recovery tube.

If there is a reverb installed, then the tube line up would be 2xECC83, 1xECL86, 2xEL84, 1xEZ81. There seems to be 6 sockets from the pictures, so may be that's it? 

[Madison]

What I want to remind everyone is, this thing ONLY has 2 preamp tubes.

That's one more than the 1930 has. The 1930 only has 3 tubes, one 12AX7 and two ECC86s. And the board in your amp looks very different from the board in a 1930. You may have to draw a schematic to tell what you really have. I'd be surprised if it matches any stock Marshall amps. I think you have a very special amp... or, a very big hack.

Does the tremolo work?

Do I see a 7 lug terminal strip mounted on the board???

My guess, it was a very special amp with a preamp mod; terminal lug on the board.

Haven't tried the tremolo

Found this at drtube:

In 1965 Marshall introduced the 18W "practice" combo amps. Although they were not very loud, they certainly could "rock". There were originally 3 combo models: 1958, 1973 and 1974. They had a tremolo and an optional reverb. These amps used two EL84 tubes in the power amp, three ECC83's in the pre amp and an EZ81 rectifier in the power supply. If the reverb was fitted, an ECL86 was used as the reverb drive/recovery tube.

If there is a reverb installed, then the tube line up would be 2xECC83, 1xECL86, 2xEL84, 1xEZ81. There seems to be 6 sockets from the pictures, so may be that's it? 

There are 5 tubes TOTAL
two 12ax7
two ECL86
and I am guessing one EZ81, since the lettering is rubbed off.
No reverb.

[Willabe]

and I am guessing one EZ81, since the lettering is rubbed off.

9 pin socket? 6.3v heaters?


            Brad     

[Ritchie200]

This is interesting.  It is indeed the 1930 Popular circuit built from '72 to 73'.  However, the Popular only came in a 1x12 configuration.  So, either that chassis was mounted in a 2x10, 18 or 20 watt cabinet, OR this may be a real rarity.  Did you specify the speaker arrangement in your letter to Marshall?  This may be special.

Jim

[jazbo8]

There are 5 tubes TOTAL
two 12ax7
two ECL86
and I am guessing one EZ81, since the lettering is rubbed off.
No reverb.

Got to get better glasses... This is an odd one.

[JB]

This is interesting.  It is indeed the 1930 Popular circuit built from '72 to 73'.  However, the Popular only came in a 1x12 configuration.  So, either that chassis was mounted in a 2x10, 18 or 20 watt cabinet, OR this may be a real rarity.  Did you specify the speaker arrangement in your letter to Marshall?  This may be special.

Jim

They did make a 2 x10 1930.  I had one.  Just like the Chambonino repair linked earlier in this thread:

http://www.chambonino.com/work/work11.html

However that is a single valve pre-amp and no EZ81.  So the OP's amp is either a one-off/rarity or a hack of another model.

JB

[Madison]

Here's a couple of more pics with my crappy camera for kicks.

Tremolo works.
Regular channel is over the top distortion......kind of fun.
The tremolo channel is okay.

Still trying to find some power tubes at a reasonable price!
Don't want to pay $160 for a NOS pair!

Peace.

[Madison]

rear

[Madison]

PT OT

[DummyLoad]

Here's a coupl eof more pics with my crappy camera for kicks.

Tremolo works.
Regular channel is over the top distortion......kind of fun.
The tremolo channel is okay.

Still trying to find some power tubes at a reasonable price!
Don't want to pay $160 for a NOS pair!

Peace.

http://www.ebay.com/itm/NOS-PAIR-RAYTHEON-ECL86-6GW8-POWER-TUBES-VERY-STRONG-TIGHTLY-MATCHED-240-241-/111199590799

60 bux for a couple of japanese mullards. decent tubes.

--pete

[Madison]

Cool, thanks for the link