Mojo JTM45 Design....Not Really a JTM45. Now I need help

Share your home builds, knock offs and ground up customs.
Post Reply
jrewing
New Member
Posts: 41
Joined: Sat Dec 31, 2011 12:11 am
Just the numbers in order: 7

Mojo JTM45 Design....Not Really a JTM45. Now I need help

Post by jrewing » Sat Jun 23, 2012 4:37 pm

Hey Folks,
So, on my newest build I made the mistake of buying a Mojo JTM45 chassis just to realize that it can't accommodate KT66's. I have always received decent service at Mojo and the prices are good as I have a dealer account, but this is just simply not having a clue about a JTM45. On my last build, I built an 18 watter using the appropriate Mojo chassis and it worked great, but now I am not having the same luck. The Mojo chassis is designed for EL34's and I am thinking about converting this one to a JTM50. Can I do this with the Mojo british 45 trannies? I would assume it should be fine since the Mojo design calls for these trannies along with the EL34's. Any issues converting this to a Triode Black Flag with the Mojo OT?

Thanks Guys

robnoxious1
New Member
Posts: 5
Joined: Tue Jun 12, 2012 3:16 pm
Just the numbers in order: 7

Re: Mojo JTM45 Design....Not Really a JTM45. Now I need hel

Post by robnoxious1 » Sat Jun 23, 2012 5:29 pm

I wonder if they accidently sent you a 50 watt chassis? You should email Jason, he was really helpful to me when I had questions.

jrewing
New Member
Posts: 41
Joined: Sat Dec 31, 2011 12:11 am
Just the numbers in order: 7

Re: Mojo JTM45 Design....Not Really a JTM45. Now I need hel

Post by jrewing » Sat Jun 23, 2012 7:10 pm

The Mojo JTM45 design actually calls for EL34's. The chassis will only accommodate the Mojo PT and The PT cut out is way too close to the socket to accommodate a KT66. I am not following the Mojo layout as I think the Triode layouts make a bit more sense logistically and historically. I would have opted for the Triode chassis if it were aluminum, but it is steel. I am assuming I can make a few mods on the circuit board and screen resistors to make it a JTM50, and since the Mojo Trannies are for EL34's anyway, I should be fine, right? Any advice would welcomed!

I too have had a decent experience with Mojo, but I think they might be clueless with some things!

Smokin Tone
Senior Member
Posts: 168
Joined: Wed Feb 01, 2006 8:31 pm

Re: Mojo JTM45 Design....Not Really a JTM45. Now I need hel

Post by Smokin Tone » Sat Jun 23, 2012 10:06 pm

Yes you can do it. The trannie is great for a JTM 50. I converted one over for a guy and it's a great sounding amp. I changed it to split cathode and lowered the preamp filtering to 8uf if I remember correctly. Had a real vintage vibe. The Mojo kit is really more a JTM 50 than a JTM 45 anyway. Nice kit and components though.

ampmike
New Member
Posts: 39
Joined: Sun Mar 15, 2009 9:33 am
Just the numbers in order: 7

Re: Mojo JTM45 Design....Not Really a JTM45. Now I need help

Post by ampmike » Thu Nov 17, 2016 11:26 am

Hey guys,Mojo has the new jtm45 kit with the offset head cab.I cant seem to pull up the layout.Does anyone know any details on this circuit,just wandering if the cab is the only real difference or is the whole build is different from a typical 45,Thanks Mikey

Post Reply