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!
I would try to listen to the Martin Logan Dynamo 700 or 1000. Audiophile Liquidators currenly has the 700 listed for just under $500. I'm pretty happy with my 700 and I think it crosses over all the way down to 35 Hz.
rel t-2
Go with a Rel T3.You should be able to get one for under $500.00 used.
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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.

Bwp - I purchased my Dynamo 700 from Audiophile Liquidators and had an immediate issue with it (a problem with the wireless transmitter). They were very friendly on the phone and had me sent it back for testing. In the end, they shipped me a new sub. Every time I spoke with customer service it was the same person and he remembered me from previous conversations. I would purchase from them again based on my experience.
I'm using dual Velodyne MiniVees with my Magnestand MG-12s. Very small(10"x10"x12",sealed enclosure,8" driver,and a 1000 watt amp.Available on ebay for $300-$500
More info here
I struggled with the right low cost sub with my Magnepan MC-1's (down model from your MC-12's). After a few loaners from a good dealer, I settled on the Vandersteen 2wq. I've seen them on A'gon for not too much more than $500. They do require a crossover in your speaker wire signal path that is matched to your amp impedance. I struggled with this also until I found a used Dynamicap. Great match now, plus I hear no degradation with the Dynamicap in the signal path. My dealer who is big into Maggies, tells me he has quite a few happy Maggie customers with the Vandersteen sub. I tend to believe him given my own experience. YMMV.
I appreciate Tasmi's and others reponses to my questions about subwoofers for MG12's.

As I have been reading the responses, I was also cruising the internet to learn more as well as look at manufacturer sites.

I am forming the opinion that a bigger enclosure is better than a small enclosure. It seems that the larger enclosure will allow the speaker to operate more easily without the "back pressure" caused by a small enclosure.

Of course, manufacturers utilize higher power amps to get around the small cabinet size. However, this can only lead to more distortion, which can reduce the musicality of the subwoofer.

So..having frustrated a large part of the audiophile community with that comment, two more questions:

1. if the maggies are supposed to be good to 45Hz, where should the subwoofer crossover be set? I assume that it should be somewhere above the 45HZ in order to integrate preoperly. Any advice on what the frequency response should for the subwoofer?. I am thinking that it needs to be about 20Hz to 150Hz and that I would set it at about 80 Hz.

2. I am drawn to the SVS and Epik products because they are larger and heavier. If i can see my way to roughly the $700 range, I can get into one of these with 12 or 15 inch speakers. Has anyone heard any of the Epik products? Does anyone have any opinions about the SVS boxes versus cylinders?

Your responses are great - please keep them coming!
Depending on the type of cross over you're dealing with, the subwoofer will reproduce frequencies above the cross over setting and the speakers will produce frequencies below the 45 Hz just at lower volume levels. I think it's possible for an electronic crossover, think audyssey type stuff, to completely cut off frequencies, but I'm not sure about that. I think my Martin Logan references setting the crossover at 75% of the rated bottom end of the speakers for a starting point to adjust from.

Focal rates my speakers for 40 Hz to 28 kHz with a low frequency point of 33 Hz. I have a test tone CD that I tested and they were able to reproduce just under 30 Hz, but at a much lower volume. I don't know if your speakers are similar or not.
09-28-10: Bob_reynolds
$500 will not get it done. Besides the sub you need to consider room mode correction to get the most from the sub.
Yes it will, if you know where to shop.

Martin Logan subs (even their inexpensive ones) are designed to match well with their electrostats and other panel speakers. As such, they are very fast, integrate well, and are tuneful, not boomy. They're practically made to order for Maggies.

In fact, the ML subs can make mid-fi satellites sound better than you'd think possible.
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Yeah, when buying a Martin Logan sub, go for the sealed rather than the ported ones. That's what everyone says, anyway, I have a sealed one myself so I've never heard the ported ones.

Also a big sub isn't necessarily the best choice for mating with a Maggies. People often have better results mating subs with small drivers than big ones. This probably isn't due to "speed," which isn't a factor in a woofer -- all woofers are slow. But it's a commonly-observed phenomenon. What most people want in a sub that mates with a planar is clean, flat, undistorted sound. That typically means an enclosed sub rather than a ported one, tuning for accuracy and flat response rather than extension, proper damping, a linear motor, a solid non-resonant case, and so forth.

Of course, these may not be your priorities -- if your main reason for getting a sub is to reproduce dinosaur footfalls and explosions, you may want to choose extension and output over accuracy.

I wouldn't worry about enclosure size per se. It's dependent on the technology used, e.g., ported vs. sealed. What you want to look at is the sub's frequency response.

To find the best crossover point, experiment. The bottom end extension of the 12's depends on the room, and their and your position in it. Uncorrected small room response is typically very rough, and depending on whether the low end of your 12's frequency range is in a peak or null, you could either get more bass extension, or less. The key is to find the frequency that gives a good transition, using a test signal or "walking bass." Then you can experiment with raising the crossover frequency. Taking a load off the 12's woofer will allow it to play more cleanly and increase maximum level, but you'll have to balance this against the superior clarity of planar bass. No right answer here, it's going to depend on your preferences and the levels at which you like to listen.

Another consideration is that the smaller Maggies typically have a resonant bass rise to increase their extension and establish tonal balance. With a sub, that could make your system sound bass heavy. If you cross the sub over at a higher frequency, you'll bypass the bass resonance. If you cross it over at a lower frequency, you may want to equalize it out.

Finally, if budget permits, consider using two or better yet four smaller subs. Positioned symmetrically, they can cancel room modes.
The ML dynamo 500 is ported and the 700 and 1000 are sealed designs. I don't know about their higher end subs.
10-06-10: Bob_reynolds
Johnnyb53, with all due respect, the OP stated he wanted to "make a large step up sonically." A 10" driver in a relatively small 30 pound box is not going to make clean bass at anything much above a whisper in a small room. Any sub can be boomy with the right (wrong) setup. The ML sub you referenced is ported and as such we can expect its group delay to be higher and therefore, sound "slower," than a sealed design.
Right you are. I meant to recommend a sealed ML, and when I saw a $500 ML sub I got too excited. I really meant something more like ML's Dynamo 700, which is 300 watts and a sealed enclosure. While it's a little over budget, it's within reach at $700. It's also roughly a one-foot cube, which should help the WAF consideration.

I was figuring that the volume needs would be modest since the MG12 is one of Magneplanar's smaller models.
I have the Dynamo 700 and rarely use it above 1/4 volume in home theater mode. When I had it connected to the main channel pre-outs the volume was even lower. I was amazed at it capability when it first arrived. It's not the greatest sub on earth, but considering it's size and price I'm impressed.
ML subs are very hard to beat. I use the Dynamo with Martin Logan stats. Perfect blend.
I've had Maggie's in the past, MG12's, 1.6's and MMG's. A sub that I found integrated with them very well was an Onix Rocket UFW 10. Super fast and very musical. Not your typical "home theater" sound. Keep your eyes open and you can usually pick them up used pretty cheap; hey, with the budget you have, you might even be able to get two and run them as a stereo pair, one on each side so each MG12 would have its own pet subwoofer; now that would be cool! ;)