The serial number is 5266. According to the amp tech who restored it, it's a Marshall '1974' 18w 1x12. These were made from '66-'68 and are apparently quite sought after.
I haven't found a lot of info, other than that Marshall are currently re-issuing this very model.. Also, that there appears to be an active cloning community.
A friend of mine gave this amp to me a couple of years ago. I told him that it looked like an old Marshall and was therefore probably quite valuable. He still gave it to me, for which I am eternally grateful to him, since it's the best amp I've ever played. He, in turn, found it in the dumps and brought it home. In case you're wondering, I'm not going to sell this baby - at least not for any reasonable amount of money. I love it too much and it would be disrespectful to my friend.
Bonus question: Are there any well-known guitarists who were/are known to use these amps?

How many speakers? Can you see the back panel of the amp (with speaker outputs)?
If there is one, it is a JTM45. If it is two, it is a 1962 model (model, not year made). The 1962 one was known as the 'Blues Breaker', because it was used Eric Clapton in John Mayall's Blues Breakers.
posted by kellyblah at 7:03 PM on March 23, 2011

It's neither - It's a 1974 model, as you can read in the [more inside] bit. That much I know. There just doesn't seem to be that much info floating around on these amps.
posted by Zero Gravitas at 8:05 PM on March 23, 2011

Sorry I don't have an answer, but you might try a forum like The Gear Page.
posted by puritycontrol at 8:28 PM on March 23, 2011

I'm going to have to disagree with Kelly - based on the pictures and Zero's description, it is indeed a 1974x model. The 1974x is an 18 Watt, two-channel, 1x12' combo with tube driven trem and no negative feedback with a cathode-biased output stage. The 1974x runs 2 EL-84 tubes as opposed to the JTM45/1962 models running KT-66's. What's commonly known as the JTM45 was offered as a head while the 1962 was a combo that was based on the JTM45 circuit.
Marshall didn't start using any reliable dating via serial numbers until 1969 so you'll have to use the codes on the components (providing they're original) to get the year of manufacture. The speakers and transformers are the most commonly used to date these amps. Pots can also be used but they're less reliable.
The vintage amp & guitar market is still kinda squishy after being forced to have a major correction in prices due to the economy after 4 or 5 years of double digit appreciation. I live in the Dallas are and so I'm lucky that 2 of the biggest and best guitar shows in the country happen right in my backyard. The spring Dallas show is right around the corner (3 weeks) but based on what I saw as asking prices at the Arlington show last October, I'd say it's worth somewhere between $3,500 and $5,000 depending on how much is original. From the pictures, there are some cuts in the tolex on the top so that would probably affect it a bit.
posted by AskGMoney at 8:33 PM on March 23, 2011 [1 favorite]

I can't help with the dating or pricing, but from experence, Marshall is pretty good at responding to inquiries, especially with old kit. Given your location, there might well be some provenance, too.
posted by holgate at 11:48 PM on March 23, 2011

I just sent off a query to Marshall. Thanks, holgate.
As to the cuts in the tolex on top, this isn't actually damage. These cuts go right through the wood and there used to be plastic grilles that were attached. These are long lost, however. Everything in the amp is original, except for 2 pots. And of course the tubes.
posted by Zero Gravitas at 7:27 AM on March 24, 2011

1974x is the reissue, 1974 is the original model.
Based on the pics it looks exactly like my 1974x reissue. Congrats on a fabulous amplifier, I can only imagine how good the original must sound.
There isn't much info floating around on specifically your amp because they are very, very rare- I've seen actual vintage Plexis in stores and on stages, and even played them. But never an original 1974. Most of The Internet refers to these as '18 watt' amps (after their output power, of course) because the clones and derivative designs are wayyy more common than the original article. But trust me, they are a major 'thing' in the amp world because they sound so good at reasonable volumes, great for recording and on modern stages. They're still quite loud!
There's an 18watt.com which is supposed to be THE source, but I've never hung out there. Don't know of any artists having used these amps back in the day. There's a Gary Moore album with a 1974 on the cover, can't say I've heard the thing. You should know that other early Marshalls, the 1974 is itself a clone- of the Watkins Dominator. Apparently, this amp was pretty popular with some of the most famous UK guitarists: Jeff Beck, Pete Townshend, and Eric Clapton apparently all did studio work with them.
Sorry to be so late to respond, but seriously, props.
posted by tremspeed at 11:03 PM on February 15, 2012 [1 favorite]

This thread is closed to new comments.

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