Inexpensive sub for MG12's


I have been listening to my new MG12's with a 15 year old Acoustic Research sub that is a 12 inch with 175RMS amp.

The sub sounds a liitle bit boomy, there is no deinition or timbre to the bass, it cannot be adjusted to a 45 hz cutoff, and I suspect that sub is a little bit slow.

What alternatives are out there for about $500? That is my current budget given the WAF is very low over the Maggies (size along with sittng on 14 inch high wood cubes about four feet from the walls). The new Denon 103R and a SUT did not help either I suppose!

I want to make a large step up sonically and if $500 cannot do it, I want to know that so I can decide to wait until stereo spending would be more acceptable to my better half.

Advice is appreciated!
dsper
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I second the Dynamo, easily fast enough for your Maggies. Audiophile Liquidator is not an authorized dealer so I would not buy from them, you can pick one up here for a few hundred bucks.
The HSU VTF2mkIII has a crossover adjustable to 30hz. I cross over my 1.6s no higher than 40hz without bloat or boom. W/shipping and tax, just over your budget, though, new.
If you live in SoCal, like I do, you can get a discount and SKIP the shipping by going direct to HSU offices. $$$!
HSU sources subs for Outlaw.
SVS gets good press too, but I've never heard one.
With the speed of the Maggies, I think you might want to look at smaller, faster drivers. Infinity makes a subwoofer for their Cascade series that uses 4 6" drivers, with 800 Watts, to creates some pretty amazing bass. My brother has one and it is amazing how much clean, tight bass it produces. Zero boominess. Crossover goes down to 50hz, but I would encourage playing with different levels, since it will be vastly different than your 12".

They retail for $1,800...but lucky for you Vanns has them on sale for $500 til the 30th. Check it out man, might be the ticket for you.

Mot