what type of subwoofer is good for ribbons


I am looking to buy a new set of speakers I am very interested in some magnepan ribbon speakers but they dont have enough bass i also heard that you need a special subwoofer for these in order for them to sound right what would make a good subwoofer for ribbon speakers
justinroxxx
Duke (Audiokinesis) is too honorable to blow his own horn. However, nothing prevents me from doing it for him. His SWARM system is outstanding, if:

1) it's in your price range
2) you have the space to place 4 small-footprint subs
3) you can deal with the cabling for #2

I own his Planetarium Betas, of which the SWARM is an integral part. If, however, I were an owner of Maggies, Quads, or the notoriously bassy-shy M-L 'stat, I'd be all over these.
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try to find a panel subwoofer, such as the enigma or sound lab b2.

if you want to optimize coherence, a panel sub is the way to go.

unfortunately there are very few of them, and they may not extend low enough to satisfy some bass enthusiasts.
http://www.harman.com/EN-US/OurCompany/Technologyleadership/Documents/White%20Papers/multsubs.pdf

I don't know how I found it.......and can't read it. My eyes are watering so bad from this cold I can hardly see.

Somebody read it and summarize, please.
Also, please note in your answer how well your listening space conforms to the test space....mine? It couldn't.....I have an 8 sided asymmetric room with a vaulted ceiling.....a largish LR / DR in the California fashion.
> all the placement recommendations mentioned in the multisub paper on the Harman web site were very symmetrical not asymmetrical. Whether 2 subs or 4 subs, they are always in the same position on opposing walls.

The idea behind asymmetrical placement is to minimize standing waves by decreasing constructive interference i.e. each sub has a different interaction with its respective room boundary or boundaries, which smooths the overall response.

I have placed my four SWARM subs in many, many different locations, including a symmetrical setup. Trust me, you do not want to do this.