How not to use an REL sub...

[Mr_Sukebe]

I've had my sub for approx a year now. With films it's been brilliant, but it's never been plain sailing with music.
In fact if anything, it's been a real pain.

When I first bought it, I lived in my old flat, which has a serious bass "bloom" around 40hz, enough to be annoying with my existing floorstanders.
Since moving, I have a room with seemingly NO bass resonance (see the thread on Taming Room Acoustics for more details). Even in that room, I had problems with the sub, just never managing to get it integrated.

A few weeks ago I did some major moving around of my kit, and without the sub, managed to get the system to sound good in stereo.
Last night, I just couldn't resist playing with the sub again, using a high-level input from my speakers.

What I found was a couple of things:
- I'd been using my Q100 (a massive thing which positively dwarfs the newer Q150), in "depth" mode, assuming that it was the way to go. Well just for a laugh, I tried it in "slam" mode. Frankly the change was awesome. Sounds like music again, and actually integrates with my stereo speakers.
I can only assume that in "depth" mode something in the amp section changes the timing as it sounded lousy with music like that.
- I tried both the sub and main speakers on concrete slabs along with mixing them around. With the speakers on slabs, and the sub on the floor, also sounded like it had massive timing problems, the bass from the sub, just not being coherrant with the speakers. The only way that worked well was with the sub on the slab, the speakers sat on the floor. To me that infers that slabs add "speed" to speakers. Whatever, results in a much more listenable end result in the final incantation.

So, I now have a system with great room acoustics, no bass bloom, and plenty of lower level bass which is now controlled.
Rock on!!

 

[merlin]

Glad to hear you are happy

No idea on the REL, the depth mode is supposed to be for music, but room interaction is the key for most here, so experimentation is a must.

Still remain unconvinced of the virtues of most subs for music in conventional systems though, timing always seems to get compromised to me. But I guess if you are lucky enough to hit the sweetspot, then the gains across the board are worth it.

The slabs are decoupling the speakers from the floor. Have you got a wooden floor by chance

 

[Mr_Sukebe]

Mike,

I have a concrete floor. Timing does appear to have been the critical issue.

 

[Matt F]

Mmm? The joys of fine tuning a sub eh?

As I've found out having recently acquired a monster Paradigm Servo 15, it's not an easy task, even when (in my case) I don't have to worry about setting the crossover as my processor takes care of the bass management.

The Servo 15 started off in the corner - big mistake - loads of output, no accuracy giving slow-sounding, ill defined bass. I'd urge anyone to avoid subs in corners as a general rule, despite what you may have read - extra output yes, accuracy no.

Anyway, the best position (to my surprise) turned out to be level with the listening sofa but facing back down the room towards the main speakers.

However, the sub and mains weren't playing in time until I brought phase into play. The X30 control unit that accompanies the Servo 15 (which Richers are supposed to charge an extra £100 for but didn't do in my case) gives you a variable phase control.

I didn't see the point of a variable phase control but I do now. As I brought it round to 90 degrees the bass snapped into focus and all of a sudden we had everything singing in time.

Some judicial use of the volume got me to the point where you couldn't really hear the sub but when you switched it off the lower octave disappeared - exactly how it should be IMO.

Some have said that the Servo 15, whilst great with movies (which is true of course), can't "do" music - this is bollox - all it means is they didn't have it set up properly.

Matt.