I see a post from 2013 which is basically the same question. But a lot can happen in 7 years.
I have some of the wood cut for a pair of 5 cubic foot (gross) sealed cabinets. The interior dimensions are 20.5" cubed. I will be mass loading the top, sides & bottom of the cabinets. 1-1/2" baffle. Perhaps some bracing for the rear, which will depend on whether I use a plate amp or an eternal amp. Interior will have a liberal amount of Rock Wool.
The project is "designed" around the Ultimax 18. However before I bought the drivers I thought I would see if there were other drivers I should consider.
The main purpose is to deliver wooferage to my 15'x25'x9' HT room. My fronts are full range which I high pass at ~30hz. To be more precise my fronts are Magnepan MMGs sitting on top of a pair of GR Research OB "W" 12s. They will reach down to below 20hz, but when doing HT, at a reasonable volume they will occasionally make a nasty cracking sound which I interpret to be them bottoming out.
I alleviated that by raising the High pass. I never have a problem with any music.
So I am building these subs to mainly do infrasonic to ~40hz. Is there anything in the price range of the UM 18 that I should look at?
I have some of the wood cut for a pair of 5 cubic foot (gross) sealed cabinets. The interior dimensions are 20.5" cubed. I will be mass loading the top, sides & bottom of the cabinets. 1-1/2" baffle. Perhaps some bracing for the rear, which will depend on whether I use a plate amp or an eternal amp. Interior will have a liberal amount of Rock Wool.
The project is "designed" around the Ultimax 18. However before I bought the drivers I thought I would see if there were other drivers I should consider.
The main purpose is to deliver wooferage to my 15'x25'x9' HT room. My fronts are full range which I high pass at ~30hz. To be more precise my fronts are Magnepan MMGs sitting on top of a pair of GR Research OB "W" 12s. They will reach down to below 20hz, but when doing HT, at a reasonable volume they will occasionally make a nasty cracking sound which I interpret to be them bottoming out.
I alleviated that by raising the High pass. I never have a problem with any music.
So I am building these subs to mainly do infrasonic to ~40hz. Is there anything in the price range of the UM 18 that I should look at?
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well, it is not a no...……………………
below 40hz, sealed, hmm.
the more the xmax plus cone area, the better.
You are probably boosting it.
So quick answer, probably not.
below 40hz, sealed, hmm.
the more the xmax plus cone area, the better.
You are probably boosting it.
So quick answer, probably not.
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Anyway, HR 'says' it's a 0.87 Qtc before any stuffing, VC heating, lossy inductance, so really only 'strong' [efficient] from ~25 Hz up, though sims ~105 dB/11 Hz/1 kW/1pi, peaking at ~128 dB/43 Hz, but you could have done this quickie sim.
Sorry, I don't keep up with the driver options, but DSP can make this one work and even one could do some physical damage.
GM
Sorry, I don't keep up with the driver options, but DSP can make this one work and even one could do some physical damage.
GM
Thanks, for the info, and yes I had done the sim. What I was hoping to get would be feed back as to other drivers which I could also sim, and decide which is the best choice prior to purchasing the driver for the cabinets.
I tend to use PE for drivers and other stuff, so I may be missing out on another driver with a similar price that might give better performance in this enclosure.
Thanks again.
The dayton and eminence are great for the money here in the states.
However, regardless of the simulations, the driver wont get louder past 100w, you will not pick up 10db if you pump 1000 watts into it vs 100.
There are jbl papers on this.
400w may, and i mean may, be 3db louder than 100w.
And the heat in the voice coil will weaken your qts and your sensitivity for 1w in.
Based on what i know, double 18 seemed a better air pump than 4x12.
Another option is 21" or 24", but they are pricy, and require a bigger box and probably need more boosting for flat down to 30hz also.
However, regardless of the simulations, the driver wont get louder past 100w, you will not pick up 10db if you pump 1000 watts into it vs 100.
There are jbl papers on this.
400w may, and i mean may, be 3db louder than 100w.
And the heat in the voice coil will weaken your qts and your sensitivity for 1w in.
Based on what i know, double 18 seemed a better air pump than 4x12.
Another option is 21" or 24", but they are pricy, and require a bigger box and probably need more boosting for flat down to 30hz also.