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In the Forum: Horn-Loaded Speakers
In the Thread: Macondo's Axioms: Horn-loaded acoustic systems
Post Subject: Lower/Upper Mid Transition PointPosted by jessie.dazzle on: 4/17/2008
Jessie wrote :
"...In the case of the system I am building, one can happily sit straight in the firing axis of any of the horns without experiencing the above-mentioned unpleasantries... No cringing (and this while using the older metal diaphragms). The reason for this I believe is directly related to the fact that I'm not asking each horn to cover such a wide frequency range..."
Well that was then; I now feel a sort of responsibility toward other S2 users to relay that the logic expressed above is incorrect as applies to my system.
At the time I made that statement, the transition point between the lower mid and upper mid horns was at 4800 Hz, meaning that the upper mid driver was asked to play a little more than a single octave (from 4800 Hz to just over 10 KHz), so quite a narrow range.
The other day I lowered that transition point down to 3200 Hz, which in fact resulted in an improvement (the smaller horn does the 3200 - 4800 Hz range better), and still no cringing. I have not tried lowering this point for quite some time, but I do know that doing so, in my case, used to induce the beginnings of cringe.
I then tried the 8 Ohm taps, and still no cringing.
So how then to explain this non cringe-inducing behavoir :
1) A lucky interaction with the new room.
2) The addition of upper base horns is balancing things out.
3) The possibility that the textured coating I have applied to the inner surface of the horns may be acting to make the horns less cringe-inducing.
Romy wrote (see "The Budification of Macondo" post) :
"...I use photographic masking tape… I am sure anything else might be used. Bud uses paint’s drops. I might do paint as well eventually after I experiment with removable patterns and found that the whole idea worth to be employed..."
Well its definitely not the same thing as "Budifying", but just before moving the system, because I had things disassembled, I coated the entire inner surface of all horns with a mix of sand and epoxy resin (filtering the sand before mixing it with the resin). The resulting texture is very much like that of 16 or maybe 36-grit sand paper.
I will post photos once I get my camera unpacked.
The first time I listened to the horns with the texture was in the new place, where they continue to amaze (!) me, but that is also due to the contribution of the upper bass horns; wich, with WAF problems behind me, I am finally able to use in the same room as the other horns. In fact, I will only know more about the real effect of the texture by getting a duplicate horn, but without the texture, into the same room and make a comparison.
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