Where 2 sit audio quiz

C'mon Rives get off the fence...LOL

Hey Sean, your suggestions about dealing with 'audible' issues such as hot upper mids are consistant with what I'm hearing. I should have said that I'm using the 3.6's without any tweeter attenuation, and I think that has certainly raised the higher frequency output. So re-inserting the 1.2ohm resistor would probably tame the treble response somewhat, to the detriment of transparency, as seems to be the case.
I wondered if you had an opinion on which of the 3 locations is the 12, 17 and 20.5 location?....or is that an unfair question given the parameters listed?

Lastly, would you say that the combination of speaker and room could offer an even lower output in terms of absolute low frequency extension, or perhaps a higher spl on the 20, 25 and 31.5Hz readings. I've put quite a bit of time into extracting any kind of output at 25hz and below, including placement, some diffraction materials, custom, stands, marble supports under stands, and the Cardas x-over cable kit. Would you say that's about as low as they'll go, or do you think there is more room for noticeable low frequency output? That might be a question for Tireguy perhaps, but I would welcome any input.

Rooze

Rives, thanks, I've seen your site and tried the simulator, but I can't get my room dimensions keyed in, as the max width on your simulator is 10m and my room is 15m wide.

Newbee....my room is 45'X 28'. The speakers are 12' apart, 7.5' from the front wall and toed in slightly. I have some restrictions on where the speakers can go. They can't go closer than 18" to the front wall, and can come out into the room past 9' due to the proximity of a staircase. The closest possible listening position is at the 12' point, and the 20.5' position represents the farthest distance, being up against the back wall. The seat can go anywhere between the 12 and 20.5'....Though 12 is a little close due to the staircase and WAF.
There is an 'unreal' change in sound pressure as I walk between the 12 and 20'. At the 16-17' point, the spl just drops way down, and the low frequencies almost dissapear, then it just pops right back in there around the 19-20' area. I'm not really familiar with the term suck-out, though I guess that's what I'm experiencing in the 16-17' area.
To give some more information....the points ABC on the chart are actually A=12' B=17' and C=20.5'
I was amazed that the SPL could be significantly higher at 20.5' than at 17'.
As Sean stated, the best sonics would appear to be at the 20.5 position, given the apparent smoother low frequency extension. In practice, the sound is much better at point C (20') than at point B (17'). But at point A(12') the presentation is completely different than that at point C, even though the frequency/spl readings are quite similar.

There are obviously points in between the 3 positions that are possible, but only really at +/- 12" or so from the 12/17/20.5 points.

Anyway, it's been an interesting experiment for me. Right now I have the seat at the 20.5 position. I'm enjoying the
presentation of orchestral music and some big band stuff.
When I play more 'intimate' music like Diana Krall Live in Paris, or the Sting Live CD, I wish I were back at the 12' point for that enveloping soundfield effect!!...maybe I should install tram-tracks or something.

Anyway, when I moved to this bigger place and splurged on new 'bigger' sounding equipment, I never knew there was going to be so much involved. I wish I could afford to pay for the services of a pro installer who could perhaps get me at the 14-15' point by using acoustic treatments.

What do you think Rives?....I'm 12 miles from the Packer Stadium...I could get you tickets to watch some real Football, and you could fix up my room!...seems like a fair trade!

Rooze

Sean, sorry I just posted my last response as you were writing yours, so didn't see/comment on your last observations. What you say makes good sense, particularly that most of the issues concern higher frequency brightness and sibilance effects.
I'm intrigued to understand more as to what is causing the drop in SPL at the midway (17') point. Could it be that the 17' point is actually the more neutral place and therefore the 'best' place sonically?....perhaps what I'm hearing at the 12 and 20' points is 'boom' and 'refelections' for want of better terms. The sound is good at the 17 point, but just isn't warm enough with the absence of the lower frequencies...
Believe me when I say that as far as trial and error goes, I've worked bloody hard sliding those blasted marble slabs around!....I think where the speakers are now gives me the best low frequency extension and depending on the final choice of listening position, either a wide open soundstage (far position), or an envelopling, detailed and intimate sounding presentation (near Position).

Thanks again for helping me understand what is going on and help in exploring my options.

Rooze

Sean/Rives, I had a question, the answer to which might help demonstrate each of your points of view.
I was pretty astounded at the effect of simply walking backwards through the room, from the 12' point to the 20' point, centrally of course and facing the speakers (which are now toed in only around 5* since the listening seat is so far back).

Forgetting about mid to heigher frequency anomolies and low frequency response, the thing that got to me was the shear change in volume... moving back through the 16-17 area, the volume reduced considerably then increased sharpley at the 18-19' area. I know this is somewhat indicated by the spl reading on the chart, but the actual experience of hearing this in the room was quite surprising and almost unnatural!!. Having had my original seat somewhere in the 16-17' area for a while, I'd been fighting gain issues with my LS15 preamp (another thread posted a while ago). Even after installing the ARC approved hi-gain modification, I couldn't get satisfactory volume in the 16-17' area. Now I'm sitting some 3-4' further away from the speakers, the volume has increased to more realistic levels without further equipment changes.

I'm curious to know more about the 'theory' of what is happening here. Is the 'dead-spot' at the 16' area actually the most neutral place to be? As mentioned previously, the sonic's lacked some depth and warmth and certainly lacked absolute low frequency extension in the 15' area.

Is this spl phenomenon common in room installations of these dimensions?
Is there a way somehow to treat the room to create more spl in the 15-16' area?.....this I would think is the most desireble area to sit. I've heard others offer as a rule of thumb:- measure the distance between speakers (12') and add 2-3 feet for the distance to the chair (15').
So I'm curious as to what changes in the room might equalize the spl more in the 15' area with that which is heard at both the 12 and 20' points.
Given that there is so much clearance between each speaker and the side walls, is it impossible to introduce any kind of side-wall reflective, diffuser or absorber that could be angled (perhaps) to create a higher spl in a given zone. ( the room width is 45' with the right side speaker approx. 10' from the side wall).

I've always understood the importance of room acoustics in arriving at good sound, but I've never had this kind of experience where differences are so marked within different 'zones' of the listening space.

Rooze