#1
Hey guys, I figured I'd start up a thread about my amp rebuild project. I have a Randall Hard Rock 70 from 1990 and I got it working again and figured out that another speaker I have works with it, so I'm building it into a head and 2x12 slanted, closed back cab. I don't have the money for new speakers, but I figured that if I build a nice cab I can always upgrade them and put a new head on. Here's the specs/pics of it now:

Click all of these to enlarge


I plan on making the cab slanted, at 30" wide x 23" tall x 11.5"/13.5" (top/bottom, ) deep. I'll be using 3/4" plywood, and the baffle is going to be 21.5" x 28.5" with the speakers 2" away from the edges and on an angle. The back will be closed. I have no idea of the specs of the speakers, so I'm not going to bother trying to tune the space to them (plus, I might change them eventually). I'm going to stain it with some sweet red mahogany stain to match my Gibson SG Faded.

The speakers are a Randall Jaguar RES-80 (80w 8ohm) and a University 6201 (25w 8ohm). The amp has two outputs at 40 watts 8ohms each, so the speakers will be run direct to those. The head is 70 watt solid state, which isn't ideal, but it's what I have. I'm going to throw the head in an enclosure 23.5" long x 7" high x 10" deep, and there will be some space for some interesting lighting (coming soon) to make up for not having sweet glowing tubes.

I'm going to do something interesting with the electronics. Since I want to be able to use this cab with any set of speakers no matter the ohms, I figured I'd rig up something to be able to switch the wiring. Using two 4PDT switches and 6 jacks, I figured out a way to switch between bypass, series, and parallel. Here's a diagram:



The right switch goes between bypass and series/parallel, and the left switch changes between series and parallel when not on bypass.

I know this isn't all ideal stuff to put in such a nice cab and head, but I only have about enough for these parts. I won't have more for a while, so I'm making the best of what I have, and I personally think it all has a great tone and sounds awesome.

Questions:

1. Should I put a couple of holes in the baffle for air flow? I've been looking around at ways to do it and they say definitely for bass, this is for guitar, so do I need it? I like a low-heavy sound, with clean mids and treble at no more than half, which is why I chose closed-back. Does the front need air holes though?

2. Is there a way to run a few resistors or some sort of circuit with the University so that I don't end up blowing it, but without killing the output and tone? It sounds great with the other speaker, but I want to make sure.

3. Does my wiring look good for the speaker outs? I'm probably going to post that in Ultimate Wiring thread too, but what do you guys think?

4. Any other comments/suggestions?

Thanks, and I'll keep posting here as I get going with it. I'm hoping to be done in a few weeks time, so I'll be back here at least daily.
#2
Alright, so I've got all the wood. Most of it cut, too. The tops and sides of the head and cab will be dovetail jointed, so I'm going to be tackling that over the next few days. The handles and corners are ordered, so I'll be able to rout out space in the bottom of the head for the handle to fit snug so I don't have to put anything on the cab but I can still stack it safely.

Few questions though, before I cut paint and install it, do I need to put air holes in the baffle? It's a really important question since I'm going to be cutting the remaining wood within the next few days.... someone help me out?

Also, is there a way to safeguard the speaker from getting too much and getting blown out?

If anyone has any idea or knows anyone I can ask let me know