Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Quatro on June 01, 2012, 11:31:11 pm

Title: smallest 12" combo?
Post by: Quatro on June 01, 2012, 11:31:11 pm
I have a request to build  small combo with a 12" speaker. Any ideas of the dimension of some of the smaller ones out there so I don't have to reinvent the wheel?

Thanks
Title: Re: smallest 12" combo?
Post by: daveyajd on June 02, 2012, 12:17:23 am
How big is the chassis going in it? Does it flange in or out? Big transformers? How deep is the speaker? That will tell you what you NEED to have, then mock it up from there to see if it works.

Aaron
Title: Re: smallest 12" combo?
Post by: tubenit on June 02, 2012, 05:20:39 am
Look at the dimensions of a 5E3 Tweed Deluxe and a Princeton Reverb (which can take a 12"speaker).  Those would be a good starting reference point.

With respect, Tubenit
Title: Re: smallest 12" combo?
Post by: Ed_Chambley on June 02, 2012, 10:03:48 am
Swart Space tone reverb is the smallest, lightest, most compact amp I have ever seen.  It weighs very little as it uses a 12 neo speaker.  The whole thing is smaller that the box that a 12 in speaker ships in.  Sounds great.
Title: Re: smallest 12" combo?
Post by: Platefire on June 02, 2012, 01:13:58 pm
This is not a scratch build but I picked up a Pignose G40V several years back that is 9"Deep at top, 9 1/2" deep at bottom x 13 1/2" wide x 16" high. It comes with a 10" speaker but I was able to build a new baffel and squeez in a 12". This is smaller than my DIY Champ. So the G40V has two 6L6's for 40 watts with a 12" speaker. I don't think you could get a 40 watt 1-12 combo any smaller than that. Platefire
Title: Re: smallest 12" combo?
Post by: PRR on June 03, 2012, 12:07:16 am
> the smallest, lightest, most compact

I was once working toward that. Abandoned, but still interested.

Space Tone Reverb Specifications
5W CLASS A
Speaker: 12" Mojotone BV-30H
15 7/8 T x 16 3/8W  x 9 1/4 D   ~  28lbs
(2,397 cubic inches 1.39 cubic feet)

Platefire mod of Pignose G40V
9"Deep at top, 9 1/2" deep at bottom x 13 1/2" wide x 16" high
(16 T x 13 1/2 W x 9 1/2 D)
(2,052 cubic inches 1.19 cubic feet)

Platefire's re-stuffed Pig wins by 15%. Mostly by being 3 inches narrower.

And no Neo, no shortage of power, no way-exotic chassis.

(FWIW: the Space Tone isn't Neo either.)
Title: Re: smallest 12" combo?
Post by: drgonzonm on June 03, 2012, 07:28:20 pm
How about a hat box, round 13" diameter, and a curved board.  While I was working for a cabinet maker we used a plywood which we could make really tight curves, 

THINK a round box, type A, using an early 5_1, or other. 

Just a thought 


Think out side the square box. 
Title: Re: smallest 12" combo?
Post by: Platefire on June 03, 2012, 10:03:34 pm
Har! I've been hanging on to the pig because as I get further into my senior years I think a small compact powerhouse amp will be more needed. Platefire
Title: Re: smallest 12" combo?
Post by: Colas LeGrippa on June 05, 2012, 06:29:23 pm
IMO, the smallest 12'' combo measures 12 X 12 .
Title: Re: smallest 12" combo?
Post by: bakerlite on June 05, 2012, 07:17:27 pm
IMO, the smallest 12'' combo measures 12 X 12 .

Maybe so but you'd have a considerable depth...

Not to mention you'd want a 12.5 by 12.5 baffle board.
Title: Re: smallest 12" combo?
Post by: drgonzonm on June 07, 2012, 07:12:50 pm
Assume that you can find a wood tube the same diameter of the speaker and you mount with outside dia of tube same as outside dia of speaker then area of cabinet is 89% of square cabinet. 

Any one for speaker pi  :l2:
Title: Re: smallest 12" combo?
Post by: Rev D on June 10, 2012, 12:41:04 pm
 I had done some fiberglass work years ago on my Z car, using layed up fiberglass over styrofoam and it really worked a treat. I would almost consider trying it again for a small fiberglass cabinet for a combo amp. I say ALMOST because the thought of scratching my arms bloody messing with fiberglass batting has made me come to my senses... I often thought thought with a properly done glass cabinet and a neo speaker it would be possible to build something pretty darn light and still sound decent. As I say though, working on fiberglass in Az. in the summer quickly worked out the chance of that happening heh..

Regards,

Don