Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TubeGeek on January 01, 2016, 01:50:23 am
-
I have been building a few 18W mojo kits this winter and wanted to share how this one came out. It was customized a bit from the standard mojo kit.
I added VVR and it works great in this circuit. I also modified the layout from mojo and made a few component changes to my liking and styling. I used one of Doug's 3 position switches for off/standby/play which then allowed me to use the empty hole for the VVR master control pot.
This project in particular need a little help with the low end due to the speaker choice. I used a brand new Celestion speaker...The G12 Cream 90W alnico model.
I am pleased with the faceplate and backplate design on this project, it ties in with the cream speaker.
This amp sounds really quite nice to me. I have another of these kits coming up on the bench next week too, only it's not going to be as customized.
-
Looks great! :icon_biggrin:
Where did you get the chassis and cab?
-
Nice!
-
Looks great! :icon_biggrin:
Where did you get the chassis and cab?
It's a mojotone kit that I have customized. I had the faceplate and backplate laser engraved locally where I am. Here is a pic of the backplate:
-
Huh, ok, thanks. :icon_biggrin:
-
Beautiful. Really nice work on the design of the cab and plates
-
Very classy looking! Congrats!
-
Hey TubeGeek, Great work as usual.
Is the face plate a black plastic with a thin cream veneer that the laser cuts through the cream to show the black???
Love the font, reminds me of a led zeplin lp cover, cool.
-
Hey TubeGeek, Great work as usual.
Is the face plate a black plastic with a thin cream veneer that the laser cuts through the cream to show the black???
Love the font, reminds me of a led zeplin lp cover, cool.
Thanks for the compliments.
Yes the faceplate is a lasermark plastic that when lasered, leaves black font. It is available in all sorts of colours.
-
That is an excellent job. I built quite a few mojo kits. can you tell me more about the Vvr circuit you used, was it a London. I have an 18 watt I built for a customer and would like to control the loudness better. can you post pictures of the install and tell us how you wired it in. I would really appreciate it, thanks Bob
-
Hey TubeGeek, Great work as usual.
Love the font, reminds me of a led zeplin lp cover, cool.
+1
Timbo, google "Led Zeppelin font"...here's one result: http://ledzeppelin.alexreisner.com/fonts.html (http://ledzeppelin.alexreisner.com/fonts.html)
avspecialist,
Here's a link to an archived topic on VVR:
http://el34world.com/Forum/index.php?topic=6899.0 (http://el34world.com/Forum/index.php?topic=6899.0)
-
That is an excellent job. I built quite a few mojo kits. can you tell me more about the Vvr circuit you used, was it a London. I have an 18 watt I built for a customer and would like to control the loudness better. can you post pictures of the install and tell us how you wired it in. I would really appreciate it, thanks Bob
I got the cathode bias VVR idea from the link that silvergun posted. All I did was build it using a terminal strip and installed it where I had room in the amp, in between the preamp board and PT.
I had to use a 3 position switch for off/standby/on. Then i used what used to be the standby switch hole in the chassis for the VVR which I just called MASTER on the new faceplate.
Pretty simple install overall and it worked nicely.
If you look closely you will notice I inverted the faceplate from mojo's. This way when you walk up to the amp, the text is facing toward you instead of away.
-
Hey TubeGeek, Great work as usual.
Love the font, reminds me of a led zeplin lp cover, cool.
+1
Timbo, google "Led Zeppelin font"...here's one result: http://ledzeppelin.alexreisner.com/fonts.html (http://ledzeppelin.alexreisner.com/fonts.html)
avspecialist,
Here's a link to an archived topic on VVR:
http://el34world.com/Forum/index.php?topic=6899.0 (http://el34world.com/Forum/index.php?topic=6899.0)
I sat down with the owner and we looked through the fonts I have on my mac. We selected 3 fonts and when I was at the laser guy's place, this font seemed to work the best so I went with it. It is a common font found in Pages or Word called "Eccentric Std".
-
Your work sure looks good James. I really like seeing young folks enjoy this stuff as much as you do. Don't ever stop!
-
Your work sure looks good James. I really like seeing young folks enjoy this stuff as much as you do. Don't ever stop!
It keeps me out of trouble :icon_biggrin:
It has got to the point where I should learn to turn it down a notch or two. I have tendency to take on too much work for my own good because I enjoy it so much. Oh well, it beats watching tv.
-
WHAT, He's a young bloke, he must be 50 then.
-
I just assumed he was young. He runs with way too much energy and enthusiasm for an old fart. I don't think his soldering station has cooled down since that Vibro-Champ! Well, maybe once when he moved back to Canada.
-
nice work. very nice.
--pete
-
I just assumed he was young. He runs with way too much energy and enthusiasm for an old fart. I don't think his soldering station has cooled down since that Vibro-Champ! Well, maybe once when he moved back to Canada.
Haha you still remember that eh! I remember doing a face palm when I realized I used conductive esd rubber mat as an under the board insulator. :l2: Good times.
I'm 37, so not too young and not too old. I feel like I am 50 though.
-
:thumbsup:
-
I feel like I am 50 though
when you hit 50, you may want to edit this post :icon_biggrin: