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yes, another floating baffle question

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9/25/1999 5:09 AM

yes, another floating baffle question

All,

I am building my own cabinet for an Allen Accomplice amp kit - I want to put a 1/2 " birch plywood floating baffle in it , with a 1-12" speaker. My question is - do you mount the baffle on side rails only ( i.e., no bottom rail), and if so, how much of a gap ( if any ) should be between the bottom of the baffle board and the floor of the cabinet ?

Thanks,

Fred G.

9/25/1999 2:41 PM

It also depends on what speaker you are going to use Fred.
A 60oz 12" ceramic magnet speaker is going to release energy differently into a 3/8" baffle then a small weight 12" AlNiCo speaker.

The floating baffle story is a little bit over stated in my opinion, but some vintage lower powered style amps do sound a little more resonant with a thin 5/16" floating baffle, as you described, but all amps and speakers don't sound great just because you float the baffle.
With everything else being equal, I think floating baffle board amps sound a bit more low midrangey to me and a little less big in the bottom end too.
I'm not saying that's a bad thing mind you.

Pre drill the 3/4" x 1" baffle hook strips to accept the baffle and the hookstrip mounting screws.
That means three holes slightly bigger in diameter then the threaded part of the screws you plan to use on two adjacent sides of the hookstrip.
Install the hookstrips verticaly with the 1" width being the part that goes to the cabinet and use 1 1/4" screws on each side. OH, use glue too.
Don't let the hookstrips touch the bottom of the cabinet either. Stick a quarter under it to hold it up.

You should have used 1 1/2" wide strips around the front of the outside perimeter of the baffle (like a small picture frame) to make it thicker where it mounts to the hookstrips and hold the grille away from the baffle when the speaker (mounted from the back) rattles it...
So you can use the same 1 1/4" screws to mount the baffle to the hookstrips too.

When you put the baffle in, hold it up from the bottom by a about 1/16". I set it on a shim too.... ususally an old long piece of 1/16" circuit board.
If you float it, and you don't hold it up a tiny amount, it might squeak or buzz later on down the road and drive you nuts. It might buzz anyhow! :>)
Remember to do all this AFTER you wrap the baffle with grille cloth and cut the rough baffle board about 1/16" to 3/32" in smaller then the opening it goes into.

Bruce

9/25/1999 5:15 PM

Thanks Bruce,

Well, I'm using a 1/2" plywood baffle, and a Weber P12Q Alnico. All things considered, then, perhaps I'll just go with a more stable mounting - side rails (hookstrips), and a bottom rail, and mount the baffle to the side and bottom rails. I don't really want to overemphasize low-mids over a big low end. It doesn't really sound like a floating baffle arrangement is really going to give me much of what I want in terms of tone. Many thanks again for your advice.

Fred G.

9/26/1999 5:16 AM

Fred, actually Ted's P12Q is one speaker that does work well with a floating baffle but the speaker could use a little help in the low bottom.
It's just not a huge bottomy sounding speaker.
Ted Weber gave me one about a year ago and at first I completely HATED it. Yuk!
It was not what I was looking for "at all" and I gave it to a buddy of mine after the first week of trying it out.
He had no speakers to play through since his were blown and he needed... something... anything.
Well, after about a month or so my friend called for me to come and get it 'cause he had some new speakers.
He had been playing his 50 watt MIG 50 through this poor little P12Q for a couple weeks.
I figured he had trashed it but I didn't really mind because (it was free) and I didn't like it anyhow.
Well, to make a long story short, I had an old tweed something or other come in and I plunked the WeberVST P12Q in it for fun because there was some trashy buzzy unknown AlNiCo in it...
Wow!
This speaker wasn't the same at all! It sounded very good!
I've tried it in a number of different amps and cabinets since it was broken in, and, did I say it sounds really good now?

FWIW: I though the best sound was in a cabinet about the size of a black face Deluxe and it had a 3/8 fir plywood floating baffle too.
The only P12Q type speaker I've heard that sounded as good or better was a real superb condition 1960 Jensen P12Q.

Bruce

9/27/1999 1:25 PM

You can make the cabinet with fixed (glued) side cleats and a bottom cleat that is screwed (only, no glue) to both the cabinet & baffle.

Build the cabinet as Bruce suggested, shimming to keep the lower edge of the baffle from touching the bottom panel. Screw the bottom cleat to the cabinet and the baffle. Try the amp both ways, free floating, or with the bottom cleat. At least you'll be able te sample the sound for each case. !/2" plywood and a stiff 12" speaker may not flex much, even without the lower cleat in place.

9/27/1999 3:59 PM
Bruce	Yeah, this is exactly the way my 2x12" Bluestone 30 watt amp cabinet is built. The large space between the two 12" leaves a perfect spot to attatch a 4"L x 3/4" x 1" cleat to stiffen up the floating baffle if you want to. No reason not to employ that with a single 12", but, hold the speaker frame up from the bottom by an inch or so to make sure you can get the cleat mounted. Bruce

9/28/1999 11:49 AM
Andrew	Hi Bruce, Thanks for the pointers! One question, though: why is it important for the 'hookstrips' to not touch the bottom of the cabinet? Cheers Andrew

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