Building amp heads and guitar cabinets?

[audio_moksha]

Hi folks,

I'm in the process of building a tube amp head and I would also like to build the enclosure for the amp head, as well as a 2x12 cab. Could somebody kindly guide me to any well documented projects of this nature? Constructing the cabinets should be easy but what I really don't know is what would be the best way to put on the tolex covering as well as the piping and in what order (i.e tolex before gluing the panels or vice versa?)

Thanks.

[getafix]

hmm I'm also looking for a good diy page for building cabinets... when I find it I'll post it here

I found this a couple of months ago... but not really what I'm looking for

http://www.diyguitarist.com/GuitarAmps/FFSpeakerCab.htm

okay here's the that I was saying

http://www.alloutput.com/se5a/index.html

keep us updated.

[audio_moksha]

Hey getafix, the alloutput article was definitely useful; thanks for that. Now all I need to know is how to install piping. I'll keep my eyes open and if I find anything I will definitely post it here...

[Nigel Goodwin]

You might find this a useful site?

http://colomar.com/Shavano/construction.html

[Brett]

I sometimes build guitar amps and cabs, but I often farm out the cab construction. I also play bass, build bass rigs and am starting to build a new PA.

In all of this, I've learnt a few things that I apply to my designs, but others may not.

- use quality ply. Brace the corners of the cab as shown in some of the links, but I also add a couple of x-braces as more typically seen in hifi builds. "resonant' enclosures are a bit hit and miss so I prefer to concentrate on the amp and drivers.
-- If you don't have a lot of tools, go to a timber specialist to buy your ply and get them to gut it for you on their big table. It'll be more accurate, and (mine) usually go together perfectly.

- Use urethane glue, but you'll need good clamps. It also expands to fill any small gaps which is handy for sealed caps.

- When the cab is complete, I usually give the inside a coat of epoxy thinned down as a moisture sealant. Probably not neccessary, but it takes 10 min and 50c so why not.

- Flip out handles are useless, use recessed metal ones. Wherever you put them make sure they're actually useful, ie placed where you will actually be able to grab then and carry the box comfortably. A mate build a cab once with the recessed side handles at about 20*. Everyone gave him stick until they saw they were angled perfectly for him to pick it up and carry and keep his wrists straight.

- I don't like carpet. It's the easiest to apply but you'll have an olefactory memory of every gig. Tolex/vinyl scuff and tear easily, so I've settled on Rockard paint or spray on ute/truck bed liner. Indestructible and looks good for a long time. Most gear is painted or covered black anyway.

- if you use more than one driver, stack them vertically. No horizontal phasing and you'll hear yourself better on axis. Never understood having two drivers blasting at your ankles.

- Depending upon how high the cab ends up being, put a corner handle on the top rear corner and a pair of large castors on the bottom of the rear panel, and you have a built in tilt and roll. I hate carrying things. The handle may be better in the centre of the top; you'll need to sort out what's best for you. I don't do this on my gear as I always use a removalists handtruck.

- in higher power combos, I build the poweramp into the base and the preamp + controls on the top. Run the B+/filaments up one side in a conduit, and signal up the other. Batter balance and more stable.

- a hinged tiltback isn't hard to add to the rear. Hinge it at the top, and at the bottom glue a small piece of steel with a little neo magnet glued into a recess drilled in the back to old it when not in use. I usually puf some thin carpet (ratfur) between the hinged tilt panel and the back to make sure it doesn't resonate.

- use the best (tonally) drivers you can get. Lots of great neo's out there, but one of my faves is the EVM12L (ceramic).

I've got to run. If I think of anything else I'll add it later.

[Nigel Goodwin]

Originally posted by Brett
- use quality ply. Brace the corners of the cab as shown in some of the links, but I also add a couple of x-braces as more typically seen in hifi builds. "resonant' enclosures are a bit hit and miss so I prefer to concentrate on the amp and drivers.

My only comment would be to make your own choice on the cabinet material - good plywood is stronger and will take a lot more abuse than chipboard or MDF, plus it's usually lighter as well.

However, chipboard and MDF are more acoustically 'dead' so have that advantage, plus the much lower cost. As long as you're not planning abusing your cabinets?, then the lower cost option may be better?.

If you're planning lending or renting out your cabinets though?, make sure you go for very good quality plywood - as they are likely to get much more abuse than you would give them yourself.

[audio_moksha]

Thanks for that very informative reply Brett; some very useful pointers indeed. I'm still in the process of designing my amp head: a Fender bandmaster derived circuit with switchable 15W or 30W power. When I build the cab its going to be a 2x12 Celestion Greenback with black levant to match my amp head. Just one more thing; are there any real (acoustical) advantages to dove tailing? It seems like butt joints with internal bracing is every bit as sturdy than dove tailed joints...

[Brett]

Originally posted by Nigel Goodwin
My only comment would be to make your own choice on the cabinet material - good plywood is stronger and will take a lot more abuse than chipboard or MDF, plus it's usually lighter as well.

Ply is a lot tougher, taking the myriad knocks that come from an active gigging rig. Don't use MDF, . NONE of the Pro companies do.

[Brett]

Originally posted by audio_moksha
Thanks for that very informative reply Brett; some very useful pointers indeed. I'm still in the process of designing my amp head: a Fender bandmaster derived circuit with switchable 15W or 30W power. When I build the cab its going to be a 2x12 Celestion Greenback with black levant to match my amp head. Just one more thing; are there any real (acoustical) advantages to dove tailing? It seems like butt joints with internal bracing is every bit as sturdy than dove tailed joints...

Dovetialing joints is apparently stronger, but I've never had a failure with well amde and reinforced butt joints.

[Nigel Goodwin]

Originally posted by Brett

Ply is a lot tougher, taking the myriad knocks that come from an active gigging rig. Don't use MDF, . NONE of the Pro companies do.

Which is pretty well exactly what I said, except you're ignoring the fact chipboard/MDF is a lot cheaper and acoustically better!.

If you want idiots to throw your cabs about, out the back of trucks, and down steps etc. - then use good quality plywood. But many great sounding cabs use chipboard/MDF - sound just as good as plywood, and perhaps even better?, but obviously won't take the abuse of ply.