cabinet/baffle material

[Andrei_T]

Hi, I would like to ask a more experienced builder what are the best materials for cabinet/baffle and what thickness should they be, because I have read different things on some sites. Some said that the cab should be made from plywood and the baffle from MDF, others say exactly the oposite. What's best tonewise?

Thanks

[Tom Phillips]

My favorite materials for guitar amps are ¾” pine for the cab and ½” high quality plywood for the baffle. I use ¼” grill cloth spacer strips on the front of the baffle. I have also used as thin as 3/8” baffles on some guitar amps that use light speakers.
I have built big bass cabs and Stereo system speaker cabs out of all ¾” MDF. Sounded great but we really heavy.

[Bruce / Mission Amps]

This depends on what type of speaker you wil be using.
For lighter weight speakers like small 10" or 12" Alnico speakers, I like thinner 7/16" to 1/2" baffle boards and for heavier ceramic magnet speakers I use a min of 1/2" baffle up to 3/4".
3/4" is pretty much standard for most heavier magnet speakers.
I wouldn't use MDF for a baffle board, it is really not that strong in holding screws and totally dead sounding, IMHO.
Use 13mm or 19mm Baltic Birch plywood for the baffle, or if you can find it, MDO (medium density overlay) which is pro construction panel and sign painter's grade fir plywood with a thin layer of a fine/smooth, fibery material on both sides.
http://www.ply.in/mdo-plywood.htm

Bruce

[Andrei_T]

Thank you for the prompt and detailed answeres guys.

[Casey4s]

I like to use glued pine panels whenever I can, like combo cabs and smaller speaker cabinets, I use 3/4" stock, and 3/8" to 1/2" plywood birch plywood baffles. If the cabinet is bigger I use baltic birch plywood for the cabinet in 5/8" or 3/4" thickness and plywood baffles. I do not like MDF for cabinets, I don't think it resonates well and is too "cold" or "brittle" sounding but that is just my opinion.

What kind of joints do you plan to make, and how are you going to finish the cabinet?

[hartman]

What is the purpose of the baffle? Why not just mount the speaker to the main front panel?

[Tom Phillips]

What is the purpose of the baffle? Why not just mount the speaker to the main front panel?

Yes, you can do that. There are many different construction methods. If you mount the speaker to the "main front panel", then the main front panel is the baffle. How you will cover the speaker to protect it also must be considered. Some people put grill cloth on a separate frame, some mount it directly to the baffle board before it is attached to the cabinet. Another method is to screw hard perforated cover over the speaker. And there are more ways to do it.

[sportster4eva]

When you look at some of the older amps and PA speakers there is sometimes a piece (strip or cross) of the baffle left across the middle of the speaker cutout. I imagine it was to keep someone from wrecking the cone accidentally if they managed to hit the middle of the opening. It looks like a certain speaker manufacturers "beam blocker".. almost. This could be used to advantage to diffuse the beamy nature of some speakers. Anyone here ever use one of those?
Did it work?

[Bruce / Mission Amps]

Yup. It does work and I describded this exact thing to Weber many years ago when doing some research on the the beaming effect of some 10" 4x10 cabs of mine... next thing I knew there was a weber beam blocking product out on the market using what looked like a speaker' dust cover (hard dome with a metal disk backing it up), glued to a metal bracket. You would just mount it infront of the speaker.
The original ones I had been looking at were found in many old Hi-Fi cabs using similar techniques. Even many of the old VOX cabinets, had a big + routed out infornt of the speaker baffle hole
In some old speaker bottoms, I had even found metal brackets with what looked like a flatish ice cream cone, mounted in front of the dust cover with the pointy end of course aimed at the speaker.
I think this is actually a very old technique to tame harshness out of some speakers and cabs.
I was using a triple layer of bass drum felt (about 2" wide, three layers thick) but found the beam blocker worked better.