Added subs for kick drum range

[dj_teknovibe]

Hi ya guys and any girls on here, I have four Wharfedale Pro Delta 218B dual 18" subs and two Delta 215 mid/highs, I'm thinking of buying four Delta X15B single 15" subs so I can operate the Delta 218B subs from 30-60hz, the Delta X15B subs from 60-100hz and then the Delta 215 mid/highs from 100hz upwards.

 

My question is would you think the difference would be good adding the 15" subs for just the kick drum range? My subs are great they go quite low and give you a nice rumble in the stomach but they don't give you that slam for kick drums. I know 15" drivers are better for kick drums so I figured I'd think about adding four Delta X15B subs.

 

Thanks anyway I really do genuinely apreciate any help you people give me.

[Brian]

It might be worth having a good read up on the frequency range of a kick. Whilst the bulk of the sound produce is in the range you mentioned, the initial kick has a much more complex, and high, frequency range.

 

Bose used to make a cabinet specifically to emphasise the kick drum and, IIRC, it was essentially a bandpass unit centered on 120Hz.

[kerry davies]

Not a sound person, Brian, but doesn't the "attack" the OP seeks come from the beater at 2,000 to 4,000 Hz which is above the range of both Delta 15 and 18 inch speakers?

 

It just seems a bit lopsided to suggest he has 8 x 15 inch and 8 x 18 inch speakers which go up to 2,000 Hz and two tiny 2 inch HF units to cover all the rest. I wait to be corrected.

[J Pearce]

Are we talking kick drum, or sampled drums though?

The rave format of 18s or 21s for 'trouser wobble' and 15s (or even 12s) for 'chest kick' is fairly well established. Coverage from there up tends to be horn loaded 10s or 8s, with a tweeter box to saw your ear off if you happen to catch its narrow dispersion band.

In our slightly more expensive and perhaps more sophisticated world you can see this borne out in Funktion1s range, the infra sub with 21s or 18s (or 32" now!) are rated down to 20Hz, while the 15s are rated down to 60Hz. The tops then start around 100Hz.

 

OP - your bottom end plan will probably do what you want it to. If you're adding 15" subs I'd be looking at 12" (or even 10") tops rather than 15"s, as with your suggested crossovers you won't be using the 15" drivers ideal range. You may need to go horn loaded to get the desired SPL without needing many many boxes and dealing with the phase issues that can present.

[Brian]

Not a sound person, Brian, but doesn't the "attack" the OP seeks come from the beater at 2,000 to 4,000 Hz which is above the range of both Delta 15 and 18 inch speakers?

 

Exactly right. If the OP does a bit of an online search they'll find that the initial 'thwack' is predominantly MF and HF in nature. It's just the following thud which is LF.