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  • Vintage 1968 Marshall JMP 50 Plexi Custom Purple Stack Amplifier
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Vintage 1968 Marshall JMP 50 Plexi Custom Purple Stack Amplifier


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Vintage 1968 Marshall JMP 50 Plexi Custom Purple Stack Amplifier

Vintage 1968 Marshall JMP 50 Plexi Custom Purple Stack Amplifier

One of the rarest amplifiers on the market today! We picked this up, uncirculated, from the owner of 40+ years in South Wales. It had been purchased new from Nobles Music (still going!) by a local band, and then sold to the previous owner, a friend of theirs, within a few years. He had it looked at once in his time of owning it, by none other than Nobles Music themselves in 1994! This particular setup has been confirmed to all date to 1968 and is a matched pair from birth.

Serial Number: 11717 (Head) & 14734 (Cab)

This custom colour Marshall is truly a thing of beauty. It has all three original transformers – 1202-118 & 784-139 – which is a rare occurrence. There are relatively few components changed on the circuit board. The capacitors have been changed in the past, along with the EL34 valves. However, the ECC83 valves are period correct Philips. I’ve never seen a plexi panel in such good condition with no cracks or stains.


The cabinet has a matched quad of original T1221s, dating to 1st November 1968, all with original 003 cones. The purple tolex has some scuffs throughout, most notably on the bottom of the cabinet where the previous owner took off the castors. The side of the head has ‘PB’ painted on, the initials of the first band who owned it who I am trying to source the name of. This could easily be removed as it looks like household paint, but we prefer to leave it there for character and original. Both Marshall logos were missing when we purchased this, so we have put on newer replacements purely for cosmetic reasons. The standby switch has been replaced previously, and four of the knob caps are missing.

We have replaced the Bulgin socket for a modern IEC socket for safety reasons, but the original socket and lead will be included in the sale. We use TAD sockets, which mean the panel doesn’t need to be altered at all in order for them to fit. All in all, one of the most clean and original examples we’ve seen!

This amplifier has been serviced to a playable & safe standard, by one of our leading amp techs. To find out more about what our service includes, please check out our terms and conditions before purchasing.

Please have a close look at the high resolution photographs below, as these form part of our description.

At The Music Locker we will do all we can for you to get the instrument you want. You’re more than welcome to come and have a play on this, coupled with one of our vintage guitars!

Additional Information

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For more information on shipping prices, please visit our shipping page.

The Music Locker prides itself on offering vintage and collectable pre-owned instruments and equipment (the Products).

We take all reasonable steps to ensure the equipment has been inspected by a competent person in the UK to ensure it complies with UK safety standards. This may mean it does not comply with the current standards in the country in which it will be subsequently used. It is the purchasers’ responsibility to ensure it is inspected by a competent person knowledgeable with the relevant electrical safety standards within that country, prior to connecting to any live electrical circuit.

It is the philosophy of The Music Locker to keep all items as original as possible, only changing original components when absolutely necessary. This includes valves, capacitors, transformers, potentiometers, frets, etc. This gives the buyer the option of tailoring to their exact needs, and may mean that the item is not operating at optimum performance levels. Therefore, your personal preference may differ, depending on your circumstances (i.e. collector or musician), and you may decide to service the item in more depth upon receiving.

The Music Locker cannot accept responsibility for any costs of refurbishment to a standard different to the one advertised.