Sub for Monitors in a small room, good or bad?

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Hi together, some time ago i got a pair of used Genelecs for a
very nice price and now i'm considering getting a genelec sub
for them(the cheapest from the line) . With many track i cant hear
any "body" for the lower notes on an acoustic bass, attack is
there but kinda fades into nothing. My problem is that i already
had to do some very minor EQ adjustments (1-2dB) in the bass
range because of my small room which is 5m x 5m approx. The
Genelecs are 20-30cm close to a wall,bass and stereo imaging
is ok, not worldclass but the best i can get out of my current
situation.Will adding a sub only add more bloated bass and muddy
tone or can i still benefit from it?

Thanks, Martin

Archived from groups: rec.audio.pro (More info?)

Martin,

> With many track i cant hear any "body" for the lower notes <

Scott has the right answer. Room treatment, especially bass traps, will give
you much more benefit than adding a subwoofer.

--Ethan

Archived from groups: rec.audio.pro (More info?)

"Martin Porter" <proter@hotmail.com> wrote in message
news:42091c2e$0$66463$c3e8da3@news.astraweb.com...
> Thanks Scott & Ethan, i already thought about bass traps
> but i'm not sure it's really the room. Its not completely
> square, and i'm living under the roof, back of the room
> is open, there's just 2 1/2 walls. I cant put the speakers
> on the no-wall side though, my wife would kill me ;-)
> Also i think the bass is quiet accurate, not boomy or
> overdone in any way. Its just that i cant hear lowest bass
> notes at all. Could that be caused by the room too?
> If so i'll definately experiment more with the room setup
> and bass traps first. I already changed speaker setup
> many times since i got them to find the best place for them.

Standing wave problematics in square shaped rooms can definately make the
bass "disappear", yeah. Put the speakers towards the wall and move to the
back wall and/or corners to listen as an experiment. If you "discover" big
amounts of bass going around in the room you were not aware of you got bass
cancellation going on in listening position. Not uncommon in rooms like
that.

What model Genelecs are you using?

Archived from groups: rec.audio.pro (More info?)

Martin,

> i'm not sure it's really the room ... i think the bass is quiet accurate <

Yes, it's the room. All smallish rooms have severe bass problems. Not only a
severely skewed low frequency response, but also modal ringing which causes
some bass notes to linger for as long as half a second or more. That muddies
up subsequent notes. You don't hear the ringing as reverb because the
frequencies are so low. But I assure you it's there.

Here's a graph of the low frequency response in a 16 x 10 x 7.5 foot room:

http://www.realtraps.com/art_response.gif

This response is *absolutely typical* of all such rooms. Note the peak/dip
pair at 110 and 122 Hz where the response varies a staggering 32 dB across a
range smaller than one musical whole step.

And here's a plot showing the modal ringing in a similar room:

http://www.ethanwiner.com/density/empty.gif

This room is 16 x 11.5 x 8 feet. Besides the skewed LF response you can also
see the ringing decay times (the "mountains" come forward over time) at each
of the room's mode frequencies.

I promise you this is exactly what your room looks like. The lack of bass at
your mix position is caused by you sitting in one of the nulls.

--Ethan