Kalamazoo Bass 30 project (first post)

[aab0mb]

Greetings Ampagers!

First post so go easy on me....

I'm familiar with modifications and general safety procedures. But i'd say i'm still getting my feet wet in a few ways.

That being said, I just got a Kalamazoo Bass 30 chassis and control panel that's basically a project to be tweaked on and used for learning. That is unless you guys think i shouldn't change it.

http://www.netads.com/~meo/Guitar/Am...hem/bass30.gif

My main question is, are there any cool amps that i could convert this thing into using the supplied transformers? i'm into anything classic or "boutique" i guess. D*mble, trainwreck, fender, vox, marshal, etc.

Also, I'm in a little turmoil over wether i should change the sockets to be wired for 12ax7s and 6l6/6v6 instead of the 6eu7 and the 7591s as they later seems not as common. I'd like to have quick tube replacements available if possible. Seems smart. Also, i dig the 12*7 varieties for trying new tones.

I have a host of other new guy type questions i'm hoping someone might entertain...

[aab0mb]

Perhaps this is in the wrong sub forum? Or maybe there's no love for a K'zoo project around here.

[Jazz P Bass]

You really do need to define 'cool amp' better.

As to the tubes: change them to something current.
12AX7 & 6L6/ 6V6 are fine.

[aab0mb]

Well i guess i was looking for some general suggesting for a platform basis for building based on what i have already in the unit.

I'll surely do the tube type conversion to something current as a start.

[aab0mb]

i should be more clear. SOmething like: "with those transformers and those tubes you could get pretty close to (amp name here)"

I think that would be helpful. Compare and contrast in my learning.

[Jazz P Bass]

Looking at the schematic the only thing that screams bass amp is the coupling caps. (.047uf)
You could go to a .022 or even a .01 for guitar.

[The Dude]

Looking at the schematic the only thing that screams bass amp is the coupling caps. (.047uf)
You could go to a .022 or even a .01 for guitar.

Good point JPB. It would be helpful to know what the goal is here. Are we building a bass amp or guitar amp? Do we want breakup/overdrive or clean headroom? etc. If you can fill in some of the blanks here, aab0mb, it will be easier to offer suggestions. You do have limited options since you have 2 9 pin sockets and 2 octal sockets as far as gain stages go. But you can do a lot with 4 tubes.

[aab0mb]

Ah yes. Helpful suggestions.

I'll be using this for guitar purposes.

I don't need ton of overdrive. I can wait until other builds for that. I guess i'd like something in the line of clean to bluesy crunch when turned up a bit. I use my pedal board into clean amps primarily but i like to go guitar straight in once in awhile to enjoy a little bluesy overdrive.

I just took the chasis out of the horribly made head unit it came in so i could get a look at the guts. Seems like a lot of new parts in there. The seller of the amp said that he'd taken it to a local shop to have it "gone over". Seems he wasn't lying as the filter caps all look new. Haven't gotten down to tracing it yet but i assume it's all stock values as of now.

Thanks for the replies, gents. Really looking forward to seeing what i can make out of this thing!

[Jazz P Bass]

If the amp was recapped (power supply at least) half of the battle is won.

[aab0mb]

I agree about the pleasant surprise seeing the new filter caps. Really happy that part is done.

Now to tweak this think into something i can use for guitar! Pretty excited about the possibilities to have a point to point low/medium wattage amp!

Still up for suggestions as far as which way to push thing thing to get a nice clean/blues crunch machine.

[aab0mb]

http://www.freeinfosociety.com/media/images/1671.gif

I've been checking out a bunch of schematics and something along this line might work if i just build up the normal channel.

I think the same might go for the Super and Pro. This is all assuming that i change the power tubes to 6l6.

[olddawg]

You might want to start by measuring the B+ and calculating the heater current. That will tell you a lot about what you can build.

[aab0mb]

Good point. I'll grab those voltages when i get it on the bench.

[The Dude]

The Bandmaster schemo you posted would be a good choice. They break up nicely when pushed a bit. It also fits in with the tube configuration you have (2 pre's and 2 outs- omitting the vibrato and one channel). Heater current should be similar enough. The only slight problem may be that the 7591 is able to safely operate at higher plate voltages. That doesn't mean that they are using higher plate voltage in this particular amp but, as olddawg says, you should measure it first.

[aab0mb]

The Dude! Thanks! SF is a great town by the way. Played there a few times.

I think we're making some progress here. Exactly the kind of feedback i'm looking for. Should be able to get the chasis up for voltages in the next couple days.