18" Subs
Home > Home Recording Forum > Live Sound Reinforcement > 18" Subs
Posted on Jan 14, 2008 10:06 am
mclir9
www.witchsmark.com
Member Since: Aug 13, 2006
Are 18" Subs sufficient for producing nice punchy Kick Drum sounds or will 15's do better? Are 18's OK for Rock type music or are they better for like really Super Over Bass Pop Music??
[ Back to Top ]
Jan 14, 2008 10:09 am The "punch" wouldn't come out of the 18". The last PA I had consisted of 18" subs, and I believe 12" w/ horn hipacks and the sound was very good. The subs were running like 200 hz and lower (or thereabouts) as a result of taking that load off the highpacks the 12" really performed much better...
The 18" takes over the "boom" part, so the hipacks don't have to reproduce it, making that a lot more efficient for the "punch"...
Jan 14, 2008 11:10 am 18 inch subs usually fill me up at lunch though sometimes I need two :)
Jan 14, 2008 11:10 am hahaha
Jan 14, 2008 11:26 am No thanks, I already had 2 15" speakers today, I'm stuffed.
To answer your question. It's all about application. The size difference between a 18" speaker, and a 15" speaker, is about excursion. (Excursion is how far a speaker will move.) The more excursion, the lower the frequency. Also, surface area comes into play. The more surface area you have, the farther the throw of sound. So, if you are doing small rooms, then 15" speakers are fine. Larger rooms, I would go with 18" speakers. If you do decide to go with 15" speakers. Then I would suggest double 15" cabs. You get coupling action with a double cabinet.
mclir9www.witchsmark.comMember
Since: Aug 13, 2006
Jan 14, 2008 01:15 pm Right now we are using 2 - 18" Subs and 2 - 15" Speakers with Horns. We only use the 18's when we play outside gigs, as inside they are just tooooo much. Not too long ago, a post somewhere on here had me wanting to go ahead and invest in 2 - 12" Speakers with Horns instead of using the 15's. So my idea was to buy 2 - 12" Speakers w/Horns for Mids and Highs, and then use the 15's as Inside Gig Subs [I would unplug the Piezo Horn in the 15" of course], and the 18's as normal for Outside Gigs keeping my new 12's a constant for Highs/Mids. Does this sound like a good idea??
Jan 14, 2008 02:13 pm Sorry to say this. But, no. This will not work. A top box, weather it has a 15" or 12" speaker, has a resident frequency in the 250hz to 500hz range. A sub will have a resident frequency of about 60hz to 80hz. (Resident frequency is all about box dimensions and porting.) So you will never get the amount of bass you want out of it.
Try just turning the send to the double 18" box down. There is not a law saying that they have to be wide open all the time.
Jan 14, 2008 02:28 pm Quote:
There is not a law saying that they have to be wide open all the time.
But mine goes to 11...
mclir9www.witchsmark.comMember
Since: Aug 13, 2006
Jan 14, 2008 03:03 pm Thanks Rob. I think you are misunderstanding my last post. I plan on using a Crossover to send the Lower frequencies to the Subs whether, they are the 18' or the 15's, and the Mid/High frequencies to the 12's with the horns. Your saying that using the 12's instead of the 15's for my Mid/High signal from the Crossover won't make any difference in sound. I tend to remember someone on this board at one point saying that using 18's as Subs and 15's as Mid/Highs was redundant and overall the highs/mids wouldn't be as clear using the 15's, and that 12's would be better for the Mids/Highs coming from the Crossover. Is this not true, cause I would hate to invest in the 12's to try to get a clearer better overall sound just to be a waste of $$$?
Jan 14, 2008 03:07 pm 18's and 12's would better cover the ranges than 18's and 15's, yes, but either can get the job done...given the choice I'd have 12's, maybe even 10's in the mids...10's might be a bit much tho...depends on the cabinets, crossover cutoff and such too.
Jan 14, 2008 03:19 pm Uh... Yeah, I see where you are going with that. Although, not all 15" speakers are created equal. I do agree, that I also prefer the 18" to 12" combo.
Jan 14, 2008 03:20 pm Not all of anything is created equal this whole thread is painting with a very broad brush.
Jan 14, 2008 03:31 pm Very true!
mclir9www.witchsmark.comMember
Since: Aug 13, 2006
Jan 14, 2008 03:42 pm So again, this is one of those things where it depends on the equipment I am using and just what sounds good. But, 18's and 12's would cover more of the frequency spectrum. Got ya.
Jan 14, 2008 03:44 pm pretty much, yeah...placement, cab size and design, frequency cutoff ranges and sharpnesses...room size and shape...it all plays a role.
