Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by Bg »

Mattallica wrote:The blue tolex is nice. There's enough black and tweed around the place already
and banned....
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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by Jay »

Bg wrote:vinyl is a complete PITA to apply, you'll find the tolex much easier and it will turn out much better.
Yes, I don't know why I went that way :crazy: Anyway, there's always the TolexMeister just across the border :)
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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by Bg »

jvpp wrote:
Bg wrote:vinyl is a complete PITA to apply, you'll find the tolex much easier and it will turn out much better.
Yes, I don't know why I went that way :crazy: Anyway, there's always the TolexMeister just across the border :)
Its easier to obtain... some is workable but the majority just doesn't want to conform. Then the backing comes off etc etc...

But I know that because, I've tried the same.
"What constitutes a porn addiction"
"I'd say when you keep watching after you've finished"

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Re: Building a Jansen 4/TWELVE SPECIAL copy (MORE COMPLETE)

Post by Jay »

The original Jansen 4/Twelve does have a spare triode, not used for anything which seems a pity...

So finally I managed to put that triode to use and made the following changes:
  • extra gain stage using the spare triode (separate bias and gain controlled by its own potentiometer)
  • introduced more gain in the V2 section
  • put in a Master Volume pot
These changes transformed this amp into a different beast. It can now roar with the growl of a grisly bear or wail like an old woman moaning about her lost beauty :shock:

Five knobs to fiddle with :D

Five knobs - 20210223_132818.jpg
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Re: Building a Jansen 4/TWELVE SPECIAL copy (MORE COMPLETE)

Post by Slowy »

Jay wrote: Tue Feb 23, 2021 12:50 pm

These changes transformed this amp into a different beast. It can now roar with the growl of a grisly bear or wail like an old woman moaning about her lost beauty :shock:

Five knobs to fiddle with :D
Oh well, I still have the original.
:rofl:

Keen to hear it.

And if you're still up for a challenge, I have two other stunning amps for you to clone.
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Re: Building a Jansen 4/TWELVE SPECIAL copy (MORE COMPLETE)

Post by Jay »

Slowy wrote: Tue Feb 23, 2021 2:24 pm
Jay wrote: Tue Feb 23, 2021 12:50 pm

These changes transformed this amp into a different beast. It can now roar with the growl of a grisly bear or wail like an old woman moaning about her lost beauty :shock:

Five knobs to fiddle with :D
Oh well, I still have the original.
:rofl:

Keen to hear it.

And if you're still up for a challenge, I have two other stunning amps for you to clone.

Sure, but it should be heard with your speaker, not?

Let me know when you are free. Happy to drive your way if that is convenient.

ps1 - I had to change V1 from the AX7 to AY7 to tame the beast a bit. Before that it behaved even more brutal.


ps2 - always up to challenges, but a few too many on right now
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Re: Building a Jansen 4/TWELVE SPECIAL copy (MORE COMPLETE)

Post by Olderama »

Jay wrote: Tue Feb 23, 2021 2:38 pm
Slowy wrote: Tue Feb 23, 2021 2:24 pm
Jay wrote: Tue Feb 23, 2021 12:50 pm

These changes transformed this amp into a different beast. It can now roar with the growl of a grisly bear or wail like an old woman moaning about her lost beauty :shock:

Five knobs to fiddle with :D
Oh well, I still have the original.
:rofl:

Keen to hear it.

And if you're still up for a challenge, I have two other stunning amps for you to clone.

Sure, but it should be heard with your speaker, not?

Let me know when you are free. Happy to drive your way if that is convenient.

ps1 - I had to change V1 from the AX7 to AY7 to tame the beast a bit. Before that it behaved even more brutal.


ps2 - always up to challenges, but a few too many on right now
Lol you know your getting old when you struggle to read the PS2 :rofl:
:mental:

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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by bender »

Oh man, I’d be super keen on a clone of this.

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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by Jay »

bender wrote: Tue Feb 23, 2021 4:12 pm Oh man, I’d be super keen on a clone of this.
That can be discussed, but I would like to do a couple then at least to make it more economical.

You did play the original one at the bollix which sounded superb and which then started this cloning process :D

Come and try the modded one to see if you like this variant of 3 mutations...
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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by Slowy »

bender wrote: Tue Feb 23, 2021 4:12 pm Oh man, I’d be super keen on a clone of this.
You need to play Optimus first.
Seriously.
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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by StrummersOfThunder »

Warm feelings

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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by Slowy »

StrummersOfThunder wrote: Tue Feb 23, 2021 5:29 pm Warm feelings
Nowhere near enough headroom for you, I reckon.
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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by bender »

Slowy wrote: Tue Feb 23, 2021 4:35 pm
bender wrote: Tue Feb 23, 2021 4:12 pm Oh man, I’d be super keen on a clone of this.
You need to play Optimus first.
Seriously.
I have! I loved it. But it was skull crushingly loud. Also, less cloneable.

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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by bender »

Jay wrote: Tue Feb 23, 2021 4:30 pm
bender wrote: Tue Feb 23, 2021 4:12 pm Oh man, I’d be super keen on a clone of this.
That can be discussed, but I would like to do a couple then at least to make it more economical.

You did play the original one at the bollix which sounded superb and which then started this cloning process :D

Come and try the modded one to see if you like this variant of 3 mutations...
I’d love to!

Also, I already have a tweed style cab if one could fit nicely in that format.

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Re: Building a Jansen 4/TWELVE SPECIAL copy (COMPLETE)

Post by Jay »

Slowy wrote: Tue Feb 23, 2021 8:42 pm
StrummersOfThunder wrote: Tue Feb 23, 2021 5:29 pm Warm feelings
Nowhere near enough headroom for you, I reckon.
There's heaps for intimate settings, just 'dime' it to 11 for extra warm feelings :sarc:
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