What happens to cabinet volume when doubling full range drivers?

0 Members and 1 Guest are viewing this topic. Read 2064 times.

Ultralight

  • Full Member
  • Posts: 381
How does doubling drivers relate to cabinet volume?

Lets say with a single full range driver, my cabinet is 1000 cubic inch and provides the ideal response.  (i.e. transients, bass extension etc.) 

And lets say I now want to do two full range driver side by side in a speaker and want to maintain the same transients etc.

Do I simply double the cabinet volume to 2000?  Or is there a different equation at work here so that the volume should be somewhere between 1000 and 2000?

Thanks!
UL

JLM

  • Full Member
  • Posts: 10694
  • The elephant normally IS the room
That should work for a simple sealed cabinet.  But once you have to take cabinet geometry into account that can go out the window for a variety of reasons.  Many designers of ported designs make the mistake of not realizing that a long/tall cabinet with (bass) driver at one end and a port at the opposite end is acting like a pipe more than just a simple ported design.  Moving the driver or port along the cabinet length changes the sound, like like a musical instrument. 

And this doesn't address how a smeared sound is produced outside the cabinet with two full range sources. 

Ultralight

  • Full Member
  • Posts: 381
Thanks JLM>

Love to hear anyone other comments from practitioners here.

Thanks!

UL

planet10

  • Industry Participant
  • Posts: 1935
  • Frugal-phile (tm)
    • planet10-hifi
Yes, 2 drivers, double the box volume. If vented use 2 vents (or the equivqlent single vent)

dave

Ultralight

  • Full Member
  • Posts: 381
Thanks Dave,

IF anyone would know, you would for sure.  Appreciate the response.

Problem - I want to add a 3rd identical driver to a system that was originally designed with two identical full ranger.  (Bipoles)

I want to add a 3rd driver in the box.    Obviously volume won't change.

What is the 'bad thing' that can happen in this scenario if any?  And how to mitigate?

Thanks!
UL

planet10

  • Industry Participant
  • Posts: 1935
  • Frugal-phile (tm)
    • planet10-hifi
If it is sealed, then the box Q will rise, if it is vented, the tuning will likely no longer be optimal.

dave