"TT"

I'm building a 1x12" speaker cabinet to use with my guitar amp head. I
have all the thiele/small parameters for my speaker, and have used a
program called BandBox Pro to design the speaker cabinet. I have also used
a program called WinIsd to check and both programs give me similiar
results.

I already have built a 150 litre cabinet to use with my speaker. I want to
tune my bassreflex box to 65Hz. The program says that with my rear baffle
thickness of 18mm, and 2 flush ends (I'm using a hole in the rear baffle
for port) I need to make a hole 300mm in diameter, to tune the box to
65Hz.

The port would be larger in diameter than my speaker, which is 279mm. Will
this kind of design work?


** Yes.

I built two such tuned cabinets 30 years ago - with 3 x 12 inch, low cost,
16 ohm guitar speakers in a 250 litre box.

With a horn tweeter on top and driven by a Rotel 1210 amplifier, they were
used for a " disco' system by a church social group.

The only complaint I had was there was actually so much bass the tone
controls were turned back to tame it a bit.


The program says that if I use 4 ports, 100mm each is sufficient, will
this work either? Is there any difference?


** Yes it also works and there is very little difference.



..... Phil