What makes a sub boomy?

[cdsang]

I want to do a music DIY subwoofer and was wondering what is that makes a sub boomy so when I put it all together it sounds fine. It seems it could possibly be the box. But as someone had done on here, they switched sub in the box and it was less boomy. Could it be the sub? I suppose it could play a part. The amp, well I dunno know enought to say. I suppose it could be a combination of any of the 3. KSW subs are boomy when cut high, RSW subs aren't boomy but have a brace on the inside. Anyway, what do you think? Thank you in advance.

CD

[TheEAR]

What is a BOOMY sub

Boomy subs have very uneven frequency response,and favor a few dB's over the average response in the 70-120Hz region.This is caused by improper tuning,box/driver match and no or poor EQ use when needed.

And yes the box can be a factor in boom,a very rigid well braced box is always better than a thin resonating drum like one.

Ported subs can even be underported and sound great(Aerial SW12),overporting results on performance loss and can add boom(if the woofer/box are not well matched).

First find the woofer that can do the job you want(capable one),one that also fits in an optimal box size you can manage.

Second build a very inert( and well braced)box.Make sure no unwanted air leaks put a brake on performance.

Third use a well matched amp and EQ boost or attenuation(better use the EQ to reduce than to boost,boost ALWAYS eats amp more power)

As examples lets look at BOOMY subs...

Klipsch KSW series

Sony WM20and 40(horrible boom,for deaf people)

most HTIB subs,all popular minisystems bass modules

most PC speaker "subs"

Now examples of subs that have NO boom

Sunfire (all,from Junior to Signature)

Aerial SW12(ported with sealed like bass delivery,no boom)

Revel B15(sealed with RSW15 like punch,no boom)

Klipsch RSW series(may not be linear but have no irritating boom)

Velodyne HGS(the new DD series are the very definition of clean)

Paradigm Servo Signature(as clean as it gets,new reference standard for clean and gusty)

SVS Ultra(or any SVS or HSU these are ported low and are very linear,boom...not a chance)

Hope it helps a bit