VOX AC15 [JMI] Replica Layout and schematic

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TNblueshawk
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by TNblueshawk »

Turret wrote:
...or... my layout have really deadly potential and no one was able to post comments
:lol:
Sin1949
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by Sin1949 »

Turret wrote:Thanks man!

AFAIK there was no build report done yet from my plans.

Fresh beans yea know...

...or... my layout have really deadly potential and no one was able to post comments
Hi Turret,

You did an excelent job which is much appreciated.
I am building an VOX AC 15 following your plans.
I'll post some photos very soon :)
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Turret
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by Turret »

Be safe. My prayers are with you :-D
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LuciMan
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by LuciMan »

Sin1949 wrote:.....
I am building an VOX AC 15 following your plans.
I'll post some photos very soon :)
So will I - already started (see pic) but still waiting for more parts to come! :)
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Turret
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by Turret »

Nice! Cant wait for picture show

LuciMan, I got your PM (from plexiboard), I PM you back tonite after work
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LuciMan
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by LuciMan »

@Turret:

I'm almost done with the preparations for the AC15, AC30/4 & AC30/6 w/ added TB (rear panel).
Hopefully I can start next week with soldering the tag-boards & the wiring.
I'm sure your colored layout will be of great help. :)
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dchang0
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by dchang0 »

Sorry for the necro-post.

Hey, Turret--

I've been going through the original hand-drawn Vox JMI AC15 schematic dated 1960, drawing number 0A/031, slowly preparing to buy parts, and there is one discrepancy between that schematic and yours.

R38 on your schematic is 2k2.

R38 on the JMI schematic is 1k5.

Just thought you'd like to know. It probably doesn't make much of a difference in actual outcome/sound.

Thanks for your great work!
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LuciMan
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by LuciMan »

dchang0 wrote:.... Thanks for your great work!
Yes - thanks from me too!! :)

Just to show how valuable and helpful Turret's work was for me, see Surrounded by Clones ...
I hope he'll find the time to do the same work with the AC4, AC10, AC30/4 & AC30/6 TB.
dchang0 wrote:It probably doesn't make much of a difference in actual outcome/Sound
Not that I could hear a difference ... ;)
Vox (DIY): AC3 TB SuperTwin; AC10; AC15; AC30/4; AC30/6 TB (rear); AC30/6 TB Reverb
Burns: 40th Anniversary Hank Marvin Signature, white / Double Six, redburst
Framus: Strato 5/154-54
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Turret
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by Turret »

Cool beans

You guys can like my Facebook page at www.facebook.com/turretboard.co.uk for updates

New website should be finally up later this month to
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TNblueshawk
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by TNblueshawk »

For what it's worth and if anyone wants to see another finished 1960 AC15 see below.

http://el34world.com/Forum/index.php?topic=18482.0
dchang0
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by dchang0 »

Thanks to Turret's layout and schematic, I finished my AC-15 build. See the long thread here:

http://music-electronics-forum.com/t40746/

I found a few other small discrepancies between Turret's layout/schematic and the original OA/031 schematic.

1) The input jack wiring on the amp that Turret copied does not follow the original OA/031 schematic. It appears that the JMI assembly line used a different wiring on purpose without updating their schematic, because I can find gut shots that show the modified wiring.

There is a discussion about this here. http://vintageamps.com/plexiboard/viewt ... 2&t=108211

I followed the original schematic and it works fine. There is a clear difference between the High and Low sides on the same channel. The OA/031 wiring is more complex than the wiring that Turret copied from the donor amp.

I discovered that Turret's schematic does not match Turret's layout (at least not the versions of each that I have) in just the wiring of the input jacks.

2) The wiring for the Cut pot is "backwards" in that it C11 connects to C7 instead of C9. This makes no difference in actual result--the Cut pot still works as expected. See the post here:

http://music-electronics-forum.com/t40746-2/#post434201


Other than that, I did not encounter any issues, and the finished amp works and sounds great. Thanks, Turret!

BTW, I had to convert Turret's schematic to black and white so that I could print out the schematic on a laser printer. The full-color schematic ends up with illegible text.
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xtian
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by xtian »

Wow, you spared no expense! Really nice.

But you buried the lead: how does it sound?!?
I build and repair tube amps. http://amps.monkeymatic.com
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dorrisant
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by dorrisant »

Maybe it is a momentary thing but I cannot see any layout or schematic on any of the four pages... Am I missing something?
"Education is what you're left with after you have forgotten what you have learned" - Enzo
lovetone
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by lovetone »

I Can't either, I looked several times it's not to be found.
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LuciMan
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Re: VOX AC15 [JMI] Replica Layout and schematic

Post by LuciMan »

dorrisant wrote:Maybe it is a momentary thing but I cannot see any layout or schematic on any of the four pages... Am I missing something?
I think turret's links are all gone - what a shame because he made a beautiful work.
I found a link of the AC15-layout v0.1 - fortunately I have all his schems & layouts on my HDD. :)

Cheers
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