Made this one with old parts... JTM 18 Clubman

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pleximaster
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Made this one with old parts... JTM 18 Clubman

Post by pleximaster »

I made this one for a friend and another friend of mine made a demo of it.

https://youtu.be/G-FM-Q-IMjE

best regards pleximaster
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colossal
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Re: Made this one with old parts... JTM 18 Clubman

Post by colossal »

Sounds great!! Very, very smooth. That volume swell tremolo is wonderful. Is it a typical 18W Normal and Trem channel or did you change any parts? Is that an old Radiospares OT?
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crgfrench
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Re: Made this one with old parts... JTM 18 Clubman

Post by crgfrench »

Wow love it!
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geoff 1965
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Re: Made this one with old parts... JTM 18 Clubman

Post by geoff 1965 »

good demo pleximaster,
check out those vintage components! looks like an RS output transformer and that's the first amp i've seen using old ceramic discs as couplers in the pre & power amp sections! looking forward to seeing you're second video on the development.
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pleximaster
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Re: Made this one with old parts... JTM 18 Clubman

Post by pleximaster »

Thanks guys!

geoff 1965 I have seen several old 18 Watters with ceramic discs. I am pretty new to this forum so I don't know how to post pics.

the very best regards plexi
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pleximaster
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Re: Made this one with old parts... JTM 18 Clubman

Post by pleximaster »

Here is an original 67 Marshall with ceramic discs

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geoff 1965
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Re: Made this one with old parts... JTM 18 Clubman

Post by geoff 1965 »

cool!
and yeah if you watch the guys like D-lab,uncle doug etc who restore the vintage amps it's very rare that they have to replace any ceramic discs,they must be very stable capacitors.
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Re: Made this one with old parts... JTM 18 Clubman

Post by JMPGuitars »

geoff 1965 wrote:
Thu 11/21/19 8:30 am
cool!
and yeah if you watch the guys like D-lab,uncle doug etc who restore the vintage amps it's very rare that they have to replace any ceramic discs,they must be very stable capacitors.
They can be stable. They can serve a specific purpose. And they can catch on fire.
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geoff 1965
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Re: Made this one with old parts... JTM 18 Clubman

Post by geoff 1965 »

interesting!
i'm used to seeing ceramics in the tremolo circuit and across the volume & tone pots but these amps are the first i've seen them being used to block the high dc plate voltages! this brings to light the tales of marshall in the early days using components that were at hand/available at the time.
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pleximaster
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Re: Made this one with old parts... JTM 18 Clubman

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The board...
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Daviedawg
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Re: Made this one with old parts... JTM 18 Clubman

Post by Daviedawg »

Reminds me of old home brew ham transmitters from the 50s and 60s which had a preponderance of ceramic discs. So quite likely it was a supply issue.

Dd
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Rockinrocket
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Re: Made this one with old parts... JTM 18 Clubman

Post by Rockinrocket »

All the original18 watt amps use ceramic disks as couplers that I've noticed. RS Poly C .0047ufs as well and the occasional Mustard.

We have to remember the 18 watt was the Gibson Melody Maker for Marshall. Cheap practice amp.

Great build BTW :D
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Re: Made this one with old parts... JTM 18 Clubman

Post by zaphod_phil »

pleximaster wrote:
Wed 11/20/19 12:49 pm
I made this one for a friend and another friend of mine made a demo of it.

https://youtu.be/G-FM-Q-IMjE

best regards pleximaster
That sounds fantastic!How does your Clubman 18 differ from the regular Classic 18W?
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colossal
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Re: Made this one with old parts... JTM 18 Clubman

Post by colossal »

zaphod_phil wrote:
Thu 07/02/20 10:31 am
That sounds fantastic!How does your Clubman 18 differ from the regular Classic 18W?
Phil,

It looks like a dead stock 1974 circuit. Original Tone control on the Normal channel and Trem/Lite IIb Tone control on the Trem channel. Killer original RS output transformer!

Hopefully Pleximaster will stop by to provide some more discussion and details.
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Re: Made this one with old parts... JTM 18 Clubman

Post by crgfrench »

JMPGuitars wrote:
Thu 11/21/19 11:03 am
...they can catch on fire.
https://www.facebook.com/watch/?v=767868370687843
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Re: Made this one with old parts... JTM 18 Clubman

Post by zaphod_phil »

Rockinrocket wrote:
Fri 01/31/20 12:50 am
All the original18 watt amps use ceramic disks as couplers that I've noticed. RS Poly C .0047ufs as well and the occasional Mustard.
Ceramic caps have nonlinear properties which makes them useless for hi-fi, but great for tone in guitar amps. :D
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Crabman
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Re: Made this one with old parts... JTM 18 Clubman

Post by Crabman »

Interesting. I have steered clear of ceramics based on what I have read. That's a fine sounding amp ... not sure how much of that comes from the use of ceramic caps but it is definitely worth experimenting.
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Re: Made this one with old parts... JTM 18 Clubman

Post by zaphod_phil »

Crabman wrote:
Tue 07/07/20 9:25 am
Interesting. I have steered clear of ceramics based on what I have read. That's a fine sounding amp ... not sure how much of that comes from the use of ceramic caps but it is definitely worth experimenting.
I'm guessing that beautiful tone results from the combination of the ceramic caps and the vintage RS OT.
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