Build Your Own Clone Message Board

Hi All,

Just finished my Mojotone TMB 18 head. From the description the amp has a preamp similar to the JCM 800 series Marshall. It has lots of gain. The amp has the simple 1 meg master connected to the treble pot. From what I can tell it's a lot like the BYOC TMB 18. So you have a clean channel with a tone control and a distorted channel with treble, mid and bass controls. The dirty channel is very loud, but controllable by the master. (As loud as my Brit45). Very nice amp. Mojo does not have the BYOC step by step directions, but pretty good instructions. Not all the kits have directions, just a parts layout and schematic.

I ran into an issue with a loud hum (almost as loud as bad filter caps) on the dirty channel and ended up using shielded wire to replace the dirty channel jack, gain, treble and master controls and moving some resistors to the 1st 2 preamp tubes. Still had the hum issue. Turned out to be a bad 12AX7 tube. When debugging try the simple stuff first. Also if you get high end squeal you can just use a metal plate or metal tape on the box so the bottom of the chassis is shielded. BYOC clone provides this with their kits. The box is being built and I'll post a picture of the completed amp.

The amp sounds great and can be used on any gig without an attenuator and it's lightweight. Pics below. Sorry the workshop is a mess.

nice looking build!

_________________
Everyone likes sausage. Nobody wants to see how it's made.

Sweet looking build! Colorful, too!!

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

That looks awesome. I’m currently planning out a Tweed 5E3 right now.

Thanks guys. Getting better with each build.

The 5E3 should come out excellent. I built the Tweed Royal and it's the 5E3 and Champ designs built into one amp. Pretty cool. My experience with this stuff is it's almost always a solder joint. Inspect with magnifiers. The older I get ..... you know

Right on, I’m really looking forward to it. What speakers did you end up using for yours? Don’t mean to hijack your thread.

I definitely want to do a JCM800 or something similar someday as well. Love that head- wish I still had mine.

Yeah, the eyes are the SECOND thing to go!

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Yes as you get older, I know turn up the amp....

I tried a Jensen C12Q and it seems a little bass flubby when distorted and I was looking for a little more volume. I put in a Celestion Heritage 30 watt with the 75hz cone to push the high mid range. They also the same speaker with a 55 hz cone. The amp sounds good with that speaker. Good cleans and good distorted sounds. I think the original amp came with an Alnico speaker, but I was a concerned about the flubby sound so I started with a Jensen ceramic and then the Celestion. When picking speakers check the speaker efficiency if you are concerned about overall volume. Check Eminence speakers because they have speakers with greater than 100% efficiency if you are looking for volume Celestion is around 100% and the Jensen is around 93%. Speaker testing can get expensive see if you can borrow some from other folks to try. You will know when it sounds good or better than what you started with.

Good luck

I've seen quite a bit of negative commentary on the ceramic magnet (C-series) Jensen speakers. The alnico versions (P-series) seem to fare much better, but then again they're quite a bit more expensive. While Celestion and Eminence seem to dominate the guitar speaker market these days, be sure to take a look at the extensive line of speakers from Warehouse Guitar Speakers--excellent performance and very competitive pricing, with both American- and British-voiced models.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Thank you duhvoodooman.

I forgot to mention what speakers I'm running the 18 watt TMB through. I have a home built open back 2) 10" cabinet running 1 Warehouse British Invasion ET 10 and 1 Warehouse British Invasion Retro 10 speaker. These speakers sound really great with the 18 watter (never tried them with the 5E3). Either of these speakers are 50% less than the Celestion Heritage I mentioned. Good stuff!!

Finished TMB 18. My brother did the cabinets.

Gorgeous! Nice work.

_________________
Scott

My band, Austin Hollow

STUNNING!!!

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Looks awesome!

Thanks guys. Now I need to learn woodworking......

Nah, you just need to give your brother something REALLY NICE for Christmas!!

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2