2.1 system vs 2.0 system for Music

Ink04,

Another option you have with the RX3 is to try woofers-out versus woofers-in, as well as changing the speaker and listening positions. These can have dramatic effects on where bass modes occur in the room and cohesion relative to the listener. Have you exhausted these options?

This discussion of subwoofers got me thinking so I downloaded some of the Audio Test files from Audio Check and had a quick play using both my ears and the Decibel 10 application on my iPhone (although I can borrow a UMIK-1 microphone). The very rough and ready interrim results are quite interesting and/or depressing depending on one's perspective:

1. Apparent room resonance roughly around 30Hz or so. An online calculator suggested 42Hz
2. We both failed the mosquito test miserably but can't wait to try it on our grandchildren 

The room resonance may partly explain some of the impressions when we auditioned speakers last year. I can understand that, as I understand from this thread, integrating a subwoofer properly is not a trivial exercise. And room treatment clearly is important.

In reading some hearing data published online, it was interesting to note that at age 60 (data reference point, not our age) the male threshold of hearing is quite a bit higher than female. Assuming the age qualification, this could be a good excuse for not hearing things you don't want to 

ink04 posted:

How popular are subwoofers these days when used with a dedicated system for a music hi fi. 

It's something I'd like to try out for a while to see what areas of the sound it makes a difference. I'm thinking scale, harmonics, weight, soundstage, as well as bass extention. 

Are there any enthusiasts that have added a sub and won't be without one in their system, or those that tried and found them having an adverse effect on the sound. 

thanks. 

I run 2 Totem Acoustic subs in my system, sealed 8" with ELAC BS244 as my mains. Frankly, it is amazing. I wouldn't say I would never be without one in my system, but, I do believe as long as I use monitors/stand mounts, I will always have 2 subs in my system. 

Why do you need 2 subs:  Is having only one sub just not powerful enough?  Is is because you can't put either sub in a halfway decent location?

With one, there was too many spots in the room the bass didn't reach. Once I added the second one, the bass was pretty much equal as I walk around the room. If I only listened in the sweet spot it would not be an issue, but I don't, so 2 it is

I use one, half way down a wall, and the coverage is pretty even.

If they start to get too near to corners, or have low ratio distance differences to room boundaries then you can get resonance / dispersion / comb filter problems.

Yeah, my room is a bit too cramped to put one half way down a wall, it was something i wanted to try when i got the first one, but couldn't make it work long term. 

Yes, subs can be critical of position.  I did like the idea someone had of hanging one from the ceiling!   

I am actually toying with the idea of stand mounting them under my speakers, cannot hurt to try just for kicks

A sub beneath a standmount speaker - it seems you're in danger of inventing a floorstander!

Huge posted:

Yes, subs can be critical of position.  I did like the idea someone had of hanging one from the ceiling!   

Actually, ceiling mounting could make a lot of sense, as in most cases there is no furniture to get in the way, and no danger of tripping over it. Maybe manufacturers should consider that and add ceiling mounting brackets as optional extras.

Innocent Bystander posted:

A sub beneath a standmount speaker - it seems you're in danger of inventing a floorstander!

the size of the subs are so close to that of the speakers it could look pretty decent! and will still go lower than most floor standers I have heard, especially at 4K which this is roughly worth. I am sure I would have to spend twice that to get this performance. 

Huge posted:

Yes, subs can be critical of position.  I did like the idea someone had of hanging one from the ceiling!   

That was me in the Subwoofer in stereo set up thread. Many a true word is spoken in jest as an obvious approach for a more subtle impact on decor would be to cut a hole in the ceiling and mount the subwoofer above. Structural considerations may be required if using a Wilson Benesch, Torus though 

The problem with putting the sub at the same location as the main speakers is that the arrangement doesn't allow a smooth phase change through the crossover region.

Huge posted:

I use one, half way down a wall, and the coverage is pretty even.

Good practice here. I advise anyone with a subwoofer to start by positioning a subwoofer half way along a wall.  Then try moving in steps one way or another.  And if you like it best back where you started in the middle then that's fine.

And yes, try to have the sub away from the speakers - on a side wall, or sometimes even behind you works best.

Funny you mention that Richard, my sub is right behind my listening position - that give the right difference in speaker to ear and sub to ear distances to compensate for the sub's group delay time (and this is confirmed by measurement with REW).

Incidentally the half-way along a wall principle is also supported by mathematical modelling.  I did the acoustic modelling to work out a few candidate positions before moving the sub around to experiment with the actual sound.  Mid point of the wall behind me gave the best sound and the best measurements, so confirming one of the the theoretical set-ups.

Incidentally I did the same mathematical modelling for the main speakers.  However, in this case, to get the optimal sound, I had to move them about 200mm and 150mm away from the positions that the model suggested.  Still not a bad way to start optimising the system though, getting it within 200mm is quite close using pure theory.

Naim suggest, in the N-Sub manual, that you initially try positioning it "well away, but not equidistant from, the corners." The key thing seems to be patience, and lots of trial and error.

Chris, after a few years of trying to find the best way to set up the n-Sub, I settled on starting half way along a side wall and working in increments toward each corner and that way deciding on what worked best.  The problem, of course, is that rooms are all different and have glass and doors and furniture in all the wrong places, so it's often a case of the best possible position, rather than the ideal.

Thanks Richard, this thread is a timely reminder for me to revisit my N-Sub setup, having changed virtually my entire system since the last time I did it. I did consider trying some sort of DSP/room correction, but with a 282, I don't think a low level connection is possible, so it will have to be the trial and error method.

Chris, how are you powering the 282?  If you're using a HiCap you can certainly do it.

Of course, the other way to do it is to build a 29dB attenuator and connect a DSP to the speaker cables via that!

Huge posted:

Chris, how are you powering the 282?  If you're using a HiCap you can certainly do it.

I was dimly aware that this might be possible, but I seem to recall a comment on a previous thread (possibly it was Richard?) that this was not a good idea. Can't remember the details. 

I used dual subs (REL T7s) for quite a long time with various standmount speakers. Eventually sold them and bought floorstanders with good bass response and I'm much happier. 

Subs add stuff that regular speakers don't and I found that when things click it all sounds very good indeed, but all the tinkering, adjustments, experimenting with positioning etc. was becoming a chore and I decided enough was enough. I'd get it sounding good for a specific genre then listen to something else and be unsatisfied which lead to starting the whole tinkering process from scratch. 

If I were to use another sub now I would definitely invest in room correction like minidsp. 

If it's good for one genre and not others, then you've got a fundamental problem somewhere in the set-up, quite possibly location or a lack of adequate bass traps, causing uneven frequency response.  Dual subs can be very difficult to get right, particularly as people tend to think they'll sound best when placed beside the main speakers (they won't).

ChrisSU posted:

Huge posted:

Chris, how are you powering the 282?  If you're using a HiCap you can certainly do it.

I was dimly aware that this might be possible, but I seem to recall a comment on a previous thread (possibly it was Richard?) that this was not a good idea. Can't remember the details. 

The problem is connecting long interconnects cables to the extra output sockets on the HiCap and this putting too much capacitative load on the preamp output.
The trick is to use short interconnects from the HiCap to a DSP, and longer cable(s) from the DSP to the sub.