tight sound and tight $ sub for Silverline monitor

ML Depth -- very fast, flexible controls, and due to the omnidirectional ("Balanced Force") design, doesn't care where you put it -- even in a corner -- although right between the mains is best.

thanks, will consider it, but was hoping for something <400 and hopefully <$300

A used Hsu VTF-2 would be in your price range. Might be a little large, physically, for a bedroom but it's a great sub for the price.

For a smaller bedroom type system I recommend a 10" NHT w/ outboard amp, such as you will find here:

http://cls.audiogon.com/cgi-bin/cls.pl?homesubw&1159491380

I noticed the ad for this a few days ago. I have the same amp/sub combo in a smaller type living room system to compliment a pair of B&W N804's. The 804's have great bass but I was looking for the same thing that you are, a tad more impact and bass detail. Takes the load off the 804's, especially if you have a preamp where you can cut off your main speakers below 60 or 80 hZ.

That little NHT is truly amazing. I replaced it for awhile with a Velodyne HGS-12, so that I could verify the performance of the Velodyne before putting it up for sale, and my wife and I actually preferred the NHT. The Velodyne tended to draw too much attention to itself.

Another nice detail with an outboard sub amp is that you don't have to run a sub cable and a power cord to the speaker part of the sub, just the speaker cable. Keeps the scene a little cleaner, helping w/ the infamous WAF.

A great small sub at a nice price is the REL Q-108. They are selling them at the Magnolia HiFi in the Best Buys for only $499.