68 spec jmp/jtm, SS/GZ34 KT66 clips

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ezietsman
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68 spec jmp/jtm, SS/GZ34 KT66 clips

Post by ezietsman » Sun Jan 03, 2016 3:08 pm

Hi there,

I built a 68 lead spec 1987 amp recently.
Here's the clips, all done with Redwirez G12M speaker impulses

First is Les Paul description of amp settings on soundcloud
https://soundcloud.com/ewald-zietsman/ez68-demo-1

Tokai Telecaster (50s specs), Bass Tonestack, 27k@16Ω, Diode rectifier, settings on soundcloud, amp dimed basically.
https://soundcloud.com/ewald-zietsman/e ... with-tokai


Here's the specs:

Classictone 18033 PT
1k resistor instead of choke (waiting for a replacement Classictone 3H choke, mine has a short to casing)
JTM45 RI OT
Gold Lion KT66
V1-V3: Sovtek 12ax7wa, JJ EC83, Mullard RI
22nF couplers everywhere except PI, those are 47nF
0.68µF on V2a
Filtering is 100µF (50 on GZ34), 32, 32, 32, 32

Tonestack is switchable between 33k/500pF split cathode and 56k/250pF shared cathode, rectifier switchable between diodes + 100µF mains and GZ34 and 50µF mains, NFB switchable between 27k@16Ω and 68k@16Ω (same as 47k@8Ω)

Some pics
Image
Image
Image
Image

Cab is a Marshall 2061cx with the G12H30 Anniversary speakers. I think they need some more breaking in even though they're 5 years old O_o (I've never had a powerful enough amp before)

?Mark
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Re: 68 spec jmp/jtm, SS/GZ34 KT66 clips

Post by ?Mark » Mon Jan 04, 2016 2:14 pm

nice work!!!
:thumbsup:

ezietsman
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Re: 68 spec jmp/jtm, SS/GZ34 KT66 clips

Post by ezietsman » Mon Jan 04, 2016 3:49 pm

?Mark wrote:nice work!!!
:thumbsup:

Thanks!

Here's another short clip, random stuff. This time with my 335

https://soundcloud.com/ewald-zietsman/t ... demo-short

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Strat78
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Re: 68 spec jmp/jtm, SS/GZ34 KT66 clips

Post by Strat78 » Tue Jan 05, 2016 9:29 am

Like the tube rectifier, nice chime. Great build, would love to hear you moving some air with that 4X12!
:toast:

ezietsman
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Re: 68 spec jmp/jtm, SS/GZ34 KT66 clips

Post by ezietsman » Wed Jan 06, 2016 3:47 am

Strat78 wrote:Like the tube rectifier, nice chime. Great build, would love to hear you moving some air with that 4X12!
:toast:
That one needs a bit of breaking in, the trebles are a bit spikey. Also, its a 2x12, not a 4x12, I had the headbox made 25 inches wide, not 26", so that it will not look odd on the narrower cab.

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