Rerurn to Romy the Cat's Site

Ronnie wrote:

I'm curious about how you set up your horns in the room. From photos it looks as if they are fairly close together, compared to the wide setting you suggested I try, while our room dimensions are fairly similar? When I started pushing the horns apart as you suggested, I didn't notice a point where midrange would thin out, but the whole picture would certainly open up and become clearer in every way, like a painting on the bellow of an accordion as it's opened. The stage/sound-landscape would sort of overtake the room, or become one with it... As if the room no longer had any chance of compromising it (although there were of course still room mode problems with my single woofer per side!). Unscientifically it seemed that every room-induced reflection-problem would become percentually smaller, because the stage was life-sized. Like spilling a drop of paint on a 1x1 inch picture is worse than on a 100 x 100 inch one. I noticed you wished for a bigger room after finishing the 250Hz horn, but it looks to me as if there is room to push the speakers 1-2 meters more apart. Perhaps not related to the width dimension? Would be interesting to know a little more about your chosen speaker positions, and perhaps see what it all looks like from the listening position.

I always felt that it is very strange that some people try to propose universal rules for speakers positioning, disregarding the specifics, even as big as speakers topology. Even with the same topology there are too many differences: drivers, crossovers, shapes and many others that make the rules too much confusing or sometime not even applicable. It is possible to write up a correct methodology for a giver speaker but not for a variety of speaker. Therefore I do not think that it make any sense to share my personal experience with Macondo as other people use different speakers and therefore their mileage will very much wary…

Still, I would like to bring up some very general and not specific to any horn design points that I feel any horn person should take under consideration. I do not pretend that it would be compute guide and juts dump whatever I have atop of my mind:

1) Imaging. It is important to recognize difference between imaging and soundstage.

2) Soundstage should not be considered at all at lower levels of sonic assessments.  If to accept the following evaluation schema:

http://www.goodsoundclub.com/TreeItem.aspx?postID=50#50

then soundstage being to be important from 5th level and up. If you concern about Soundstage while your mind operate at firs assessment level then you are a fool or an audio-reviewer.

3) Imaging is supremely important element but not for listening music but for audio evolutions. Imaging is a bogus artificial element and it hardly useful (with very minor exception of few selected compositions that use space allocations). However, (very big however!!!) imaging is a phenomenal indicator of “something else”. The differences  or imperfection of system imaging always suggest that something is wrong and let to mange that “something wrong” using imaging as monitoring tool.

4) The greatest thing even was written about speakers positioning is following:

http://www.goodsoundclub.com/TreeItem.aspx?postID=994#994

This is the real high-end of the speakers positioning and it should be persuaded AFTER the rudimentary correct position was accomplished. The DPoLS is superbly difficult to accomplish but if one does it then it overwrites whatever one knows about sound redaction. I am not kidding.

5) With horns everything is much more completed as horns change a lot while you tow them in or out. Any tandem of driver/horn has a fixed angle (that I call “Horn Critical Angle”) under which the channel performs at it’s best. If you go further then the Horn Critical Angle then you lose HF and get amplitude deviations. If you go sharper then the Horn Critical Angle then you might get too brutal sound and high deviation in the channel’s transient evenness across the horn’s band pass.  This is the most critical with compression drivers that very seldomly should shot directly to ears.

6) Horns should be setup with tweeters turned off. Do not worry about sound – pay attention only in imaging. If introduction of tweeters changed imaging then you use tweeters inappropriately.

7) Buy, steal, borrow or whatever Lamm L1 or L1 preamp. You would need it only for one weekend then you might let it go. I did not see anything in Audio that might be use as remotely comparable educational tool about power of imaging or how it “might be”

8) If you use multi-channels horn then discard evaluations my mono material: the different channels should produce near identical size of the center image and it should be place at near identical distance into the death of presentation.

9) Severally and anal-retentively record each step you do during positioning, literally keep dairy. You will make mistake and will return back to the refused settings. Make your returns reproducible.

10) If you are in horns then imaging VERY strongly connected with tonal balance (ironically it is not affect the “Absolute Tone” ™). While you chase the rudimental positing then take tonal deviations under consideration. However, after the loudspeakers are positioned, the system set and you go have guts to go for DPoLS then discard tonal balance. If you found DPoLS then it will overwrite everything.

11) While you in search for speaker position then use the principles of setting focus on cameras: move forward to the selected direction until is it better, better, even more better, good, very good, excellent, perfect and then until it become less excellent. From that position you know where it was the best.

12) Never, under any circumstance angle horns or allow any none-parallelling of horns.

13) Electricity does screw up everything including imaging. If you decided to spent time with horns moving and electricity go south then shut down your system and do something else.

14)  If you as the result of your efforts accidentally (it does happen) moved your speakers and hit DPoLS (trust me: you will know it) then do NOT touch that speaker anymore!  Document and map this location with unimaginable level of precision and details. Then as a tribute to my foretelling about DPoLS send a $50 donation to your local shelter for homeless Cats and declare that audio is over. If you there then you know what I mean.

Ok, I need to run grab a bite and it was all that I had atop of my hungry head…

Rerurn to Romy the Cat's Site