Build A Bandpass Box Around This...


2006-10-20 6:00 pm
...going back to my earlier thread on the Kohler commercial... :D

Eminence KAPPALITE 3015LF

Nominal Basket Diameter 15", 381mm
Nominal Impedance* 8 ohms
Power Rating Watts 450W Music/Program 900W
Resonance 42Hz
Usable Frequency Range 40Hz-1.5kHz
Sensitivity*** 99.8
Magnet Weight 11 oz.
Gap Height 0.365", 9.27mm
Voice Coil Diameter 3", 76.2mm

Resonant Frequency (fs) 42Hz
DC Resistance (Re) 5.31
Coil Inductance (Le) 0.92mH
Mechanical Q (Qms) 6.82
Electromagnetic Q (Qes) 0.41
Total Q (Qts) 0.39
Compliance Equivalent Volume (Vas) 158.8 liters / 5.6 cu.ft.
Peak Diaphragm Displacement Volume (Vd) 846cc
Mechanical Compliance of Suspension (Cms) 0.14mm/N
BL Product (BL) 18.6 T-M
Diaphram Mass inc. Airload (Mms) 101 grams
Efficiency Bandwidth Product (EBP) 102
Maximum Linear Excursion (Xmax) 9.6mm
Surface Area of Cone (Sd) 881.1 cm2
Maximum Mechanical Limit (Xlim) 17.0mm

You guys think this is a good candidate for a 4th order bandpass box? I'm thinking DJ application...
For bandpass box accuracy of thiel-small parameters play very important part.
If ur speaker & thielsmall parameters on which u rely hv more difference, then u will not get the sound u expect.
Better check thielsmall parameters accurately, then design the box.
It will give u better results.
For DJ applications forget car subs - they are of low sensitivity and are meant to play in a really small room.

For generic DJ application I would also forget HD15-s that are meant to work in large groups of at least 4 and need separate subbass cabs below (something like X1) for anything else than hardcore techno. And I would leave scoops, that are big, heavy and a bit outdated design, to reagge sound systems:cool:

Bandbass is good but not the ideal, too - complicate to build and integrate with smaller tops that don't like being pushed down to 100 Hz and lower.

Reflex is the most versatile thing - can be integrated with wide variety of tops, are scalabele (bring one for house party, bring 8 to outdoor live band), easy to build and easy to get right.
A well designed double-15" (or 18") reflex has sensitivity around 100 dB/W/m, gives you ~130 dB at one meter, and probably go lower than a horn of similar size.

As for doubles, they are IMO worth using only if you do push-pull configuration to lower distortion. On the other hand, lots of people don't like like this low distortion sound - that doesn't sound so loud as moderately distorted bass from conventional boxes. If you do not use push-pull, two singles are the same SPL-wise, easier to carry and more scaleable.

I would suggest reading this before deciding, very good information on differences between horns and reflex.
I would suggest reading this before deciding, very good information on differences between horns and reflex.

This article by rog mugale designer of super scoop suggests :

If you were only going to use the system for small parties, or if the system was only used in smallish venues then I would go for some front loaded reflex boxes.
This brings us to front loaded vented boxes. You could use two 2 x 18” reflex boxes per side

I suggested the same thing!


2006-10-20 6:00 pm
Yeah...I have the Tuba 30 plans already but the bandpass box seems to easy to build compared to the Tuba....


I started doing the math and I'm prolly better off buying a Yorkville LS808 sub...the Tuba 30 could easily turn into a $500 investment...just $200 shy of what I could get a Yorkie for...

Yeah...I know...I'm talking blasphemy in a DIY forum... :D