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Where 2 sit audio quiz

Ok folks, don't take this too seriously now!

It's cold and cloudy here in Wisconsin and I'm bored out of my skull.

I've been messing around with different seating positions and trying to form a pattern between measured results and audible results.
I thought it might be interesting to put up measured results at 3 widely varying seating positions, and see if anyone could suggest ideas on a range of different issues. There's a $1 Million cash prize for whoever get's it right, redeemable 11/22/2064

First the setup:
Meter used is the RS digital set to slow response and C weighted.
Test tones from Rives CD 2
The Rives CD say's to use tracks 32 - 62 which are compensated for the non-linearity of the RS analogue meter. It doesn't say what to use for the digital meter, so I tried both, and the most consistent seemed to be tracks 1-31.
Anyway, the numbers are more indicative than they are absolute. If I need to re-do the test using tracks 32+ then so be it.
I used 3 different 'practical' seating locations at 12', 17' and 20.5' from the speakers.
The 20.5' position is up against the wall, which is central on a large un-draped window (a clue perhaps.. [14'x 4' approx window dimension]). I'm showing the 3 sets of results in tabular form (wasn't bored enough to bother making a graph).
Also, I'm not saying at this point which reading relates to which seating position....(perhaps the SPL level will provide the answer?)

Speakers are Maggie 3.6R's, amps are Cary V12 Mono's with ARC LS15.
I thought I would have to adjust the preamp gain at the farthest position, but it didn't require it, so all 3 positions are measured using the same volume setting on the LS15 preamp.
Questions that spring to mind....(add more if you wish).
From the results shown at http://thenaturalshopper.com/audiohell.htm

1 - which position would seem to suggest the best sonics
2 - what do the readings say about room layout and frequency response
3 - what do they indicate as far as equipment selection(speakers) for the particular room layout (example - insufficient bass response at any position, harsh treble response, or whatever?)
4 - which position do you thinks is the 12', 17' and 20.5' seating position
5 - given that the spl's are almost identical at higher frequencies, what does that say about the room layout. (given that there is a 8.5' difference between the closest and farthest seat position, shouldn't one of the columns show a consistent reduction in SPL?).
6 - what does all of this say about people from Wisconsin

What the heck!

Rooze
128x128rooze

Showing 4 responses by rives

rives
953 posts
 
1. I won't comment yet--I want to hear a few others first
2. Same as #1, with the exception of the fact that I don't have an answer.
3. Says nothing in terms of equipment
4. Same as #1, except I do have an answer
5. This is normal and what I really wanted to comment on. Only frequencies below 500 Hz are really effected by positon unless there is some significant non-uniformity in the room--say for example you have first point of reflection absorbed at one positon but not the other--then you would see a difference in the HF response. Otherwise, the higher frequencies shouldn't change significantly.
6. You really are a bunch of Cheese Heads. Go Hawkeyes!! (we play Wisconsin next week)
rives
953 posts
 
Here's a hint, Go to the free simulator on our website:
the Room Simulator . Now I don't even have to post my answers:) You will also note, that the position as Rooze found, has little or no affect on frequencies above 500 Hz.
rives
953 posts
 
Sean:

I didn't say rooms don't have an effect above 500 Hz--that would be REALLY wrong. I did say that positioning (both listener and speakers) has little effect above 500 Hz. Now that's not true in all rooms, but a room that is reasonably well balanced it is true. If high frequencies are tipped up, that will be true throughout most of the room--unless you are right up against one area that is heavily absorbing, but then this wouldn't be a well balanced room. In the bass region however there are peaks and nulls and they vary greatly by location.
rives
953 posts
 
Sean: You are right about being off axis, and I was not very clear in my comments--since we were talking about a distance from the speaker the angle of incidence doesn't change much, a highly directional speaker could have a modest difference. Now if you had a well absorbed boundary at one point (first reflection) and a highly reflected surface at another it would yield quantifiably different results, but otherwise they will be remarkably similar. Try it, Rooze did, and I'll bet you get the same or very similar results. Keep in mind--I measure a LOT of rooms under many conditions, and my dealers measure even more than I do and send in the results. I have measurements taken at a variety of locations--I do not do averaging (it masks real data).
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