MERLIN VSM OWNERS WITH SUBS

If you have already decided to try a sub, I have used REL in the past (Storm III) with good results. I did, however, sell it once I changed my preamp.
For more info, have a look at a previous thread of mine.

In a somewhat smaller room I have one Velodyne DD-15 and VSM-MX/BBAM with line-level connections to the sub from a BAT VK5i tube amp. Since the BBAM filters all bass below 28hz, using speaker-level outputs from the amp to the sub is not appropriate. You might need two subs in a room as large as yours. Corner placement is usually best with a single sub; if two subs, try one just outside each main speaker. With the Velodyne DD, two subs can be daisy-chained and controlled from one remote. In an irregular room such as yours, it might be best to identify optimal room positioning by putting the sub in the listening position, and moving the sub microphone around the room to the point where the microphone produces the most linear frequency trace on the spectrum analyzer. Then switch the sub and mike positons. If the floors or walls vibrate, try the sub on a platform such as Auralex Gramma.

With the Merlins I use a low crossover at 30hz with 12db slope. If due to large room size you're already getting weak bass response from the Merlins, you might want to cross over a little higher or play with the parametric equalizer to notch up sub output around select higher frequencies. With the DD parametric equalizer I was able to integrate bass with the Merlins +/- 2db from 15hz to 100hz.

At such a low crossover point, it will be time consuming to optimize any sub by ear. Get a sub with an integrated frequency analyzer and digital equalizer such as the DD or Thiel. Given the right set-up tools I think you'll find that differences between various hi-end subs is subtle in comparison to the differences between hi-end main speakers.

Dave

I am using the VSM M speakers in a large family room that is half underground,three of the walls are concrete with paneling. The Earthquake Super Nova 15 works great with these and offers a lot of tweeking flexibility.These can be found used pretty reasonably. I am using this without the BAM.

perhaps you should give me a call first to go over the set up and jumper situation. i will have certain recommendations that may resolve the issue for you without the purchase of a sub. the super bam mod like spencer suggested is one consideration but i have questions of the setup and where the bam is used and how.
regards,
bobby at merlin
585 367 2390

Another consideration is the room dimensions and their impact relative to speaker and seating placement. I apologize if straying too far from the original question, but just trying to help.
In my similarly-sized room, I found that measurements using an inexpensive Radio Shack sound meter and the signals from a test CD allowed me to easily plot out room response(i.e. peaks & dips at various frequencies). Changes in seating and speaker locations as small as 3-6in. made an audible difference. I thought that a larger room would allow for more bass at lowest frequencies, but in fact that wasn't the case. Some spots had pronounced bass dips as much as 10db. By moving seating I was able get smoother and flatter response. The caveat being to keep in mind Bobby's advice on speaker location. Cheers,
Spencer