Maybe you missed them the first time...:)Quote:
Originally Posted by Mustang Marvin
http://www.hostboard.com/forums/alte...ml#post1790418
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Maybe you missed them the first time...:)Quote:
Originally Posted by Mustang Marvin
http://www.hostboard.com/forums/alte...ml#post1790418
Thanks BFISH. Maybe these boxes can be saved after all...
You're welcome MM. Those are pretty good summaries, it's been cussed and discussed for a long time now.
In these boxes, it's pretty hard to screw up anything by bracing. Pretty much anything you do in that regard will be an improvement. :khan:
I really had 2 issues.
1, How and where to brace the boxes.
2, Would the addition of material inside the box negatively affect the sound.
In reading the information from the link you gave me (thanks) it was noted that the A7 or A5 cabinet (825/828) is really too large for the driver anyway. SO, the additional material (2X4's) will actually help sonically.
Sorry I missed the thread on this subject earlier. If there are others with A5 or A7's, they should read this information. Now, where did I leave my hammer...
Agreed. There is more than enough volume in there. You won't hurt it with bracing or adding to the walls. You my need to retune the port a little - but since most of 'em are not well tuned anyway.....
Last night I was eating at a big "butcher-bock" table. It was stained and varnished and very pretty. Mostly it was massive and inert. Should make a killer baffle wall. If course the A7 does not have a lot of flat front surface area, the place you'd normally but thick panel like this, but done on the sides, back or top, it should cut cabinet resonances way, way down.
Just a thought.
This is only true if driven with a very low output impedance amp, i.e. SS or some of the later PP tube amps. That said, sufficient bracing won't reduce its net Vb enough to be audible. Get carried away as one person did though and it might, depending on the final in-room tuning.Quote:
Originally Posted by Mustang Marvin
BTW, 2x4s are overkill. Scraps of 3/4" no-void plywood or knot free 1x4 boards glued vertically on edge make panels plenty rigid. Just offset them in some acoustic ratio. A couple more to create an 'X' member to tie all six side's 'rigde' boards together and you're 'golden'.
GM
Historically, the butcher block panels sold at Lowe's, Home Depot left a lot to be desired from a structural POV, but recently I happened to notice that their quality looked much improved and definitely so from a flex POV, so considering their pricing Vs BB ply, I plan to try some in the (hopefully) near future.Quote:
Originally Posted by Panomaniac
GM
Is the concern here flexibility or acoustic deadness? Think of a cabinet made of 1/2" steel. There would be essentially no flex at all, but would it be a good speaker enclosure? How about some sort of closed wall foam with infinite thickness - again, no flex, but how good a speaker enclosure would it be?
Ed
Pick one of the ~infinite combinations between the two, i.e in theory you want the cab's resonant structure to be a minimum of -25 dB (preferably -35 dB) referenced to the signal's noise floor and since it's easier to raise a bass cab's Fs far enough above its pass-band to achieve this than far enough below its Fb, rigid rules. In short, we want it to 'ring like a tenpenny nail struck with a ball-peen hammer', so either of your solutions are correct, though a bit of overkill unless used for ultra-wide BW single driver apps. From this we see that as Fb rises, at some point it becomes more practical/economical to use a low Fs material.
GM