Miab, I have very limited knowledge in construction techniques, moist prevention and how all of it might affect a big horn. My very uneducated production suggests me that it is not truly a bid deal, but of cause if go this route then I certainly will consult with specialists.

Still, the back of the horn is sealed, with strong walls. What is differences my driver sit not in box in not climate controlled storage or if it sit inside the horn in attic” I think it the same. In fact in horn it has some ventilation via the mouth. Yes, attic cone run very hot (bad for ALNICO magnets) and might go cold. The cold 15” driver would have stiffer suspension and different Fs and Q. Still, I do not think that it might be terminal or dangers for a driver.

Nevertheless, it might be a good idea to THINK about it. Perhaps it would make scene if the driver in attic or outside to put whole back chamber in thermo-protective cocoon? There are some polymers that can run hot or cool from very low voltage and I have seen some thermo-stabilizing pad were made with them. I guess they might exist in shape of blanket… A good idea to think about it is the back chamber will be exposed.

My primary concern is not driver but the horn itself. If it will be attic and let say 12 feet horn will be made from “young” wood then after a year of sitting in attic the wood will be “loosing it’s youth” and the horn would need some “help”. I do not know, I need let professions to consult me about it.

Markus wrote:

http://cgi.ebay.com/Bass-Horns-for-Ale-Western-Electric-JBL-Altec-Drivers_W0QQitemZ300388291899

I have seen it and I do not like it. I applaud to the efforts but the pictures of horns do not make me aroused.  47 feet will give you around 5msec delay – this is a LOT. The horn itself is just a part of the game. The key is how it was used, how it was fixed into the room. How the rest of the channels were organized with respect to the given large mouth. That is very complex and to do it properly it is much more complex then to built 47 feet horn. The horn like this might look like an impressive accomplishment but it might have very limited use, if any use at all. If it is done properly then people do not sell those things but they die with them, probably inside of them...

Markus, I speak as a non-commited direct radiator guy when I say that the horn EQ as a raw principle is a very powerful model that theoretically opens the door to the sort of overall efficiency that direct radiators can only dream of.  Then I will turn right around and say that if one is OK with low(er) efficiency, then indeed, horns look like a lot more trouble and expense than they would otherwise be worth.  Ironically (?), I think that many of my own hi-fi shortfalls are tied to compromises I've made with respect to efficiency, which is always a factor, after all; it's not like that just goes away.

Still, I believe that the key to any successful hi-fi installation is tied up in the idea of "careful arrangement", since care with implementing highly-developed demands will probably have more to do with success in the end than topology will.  Trite words by now, but still true.

Best regards,
Paul S

Romy, I realize that you have a good deal more acoustic drive available than I do, but here is my experience, FWIW:  I lived in a larger version of a very similar configuration for 13 years.  My listening room was in "the same" spot as you picture, with a 20' high 1/2 vaulted ceiling.   I could not really load it with 100 wpc (RM9) driving 92 dB 5-way speakers (Fulton modulars), despite a solid slab floor and a longer [reflective] wall section opposite the drivers.  I got some very nice sound at times, but no real room loading I could build on.  Later, I got some nice sound and very nice ambience (when the power was good) with 7 wpc Wright 2A3 SETs driving the 97 dB DEBZs, but this combo would not load the room properly, either.  IMO, the ML2s are at the peg driving the DEBZs into a 17' X 21' X 8' hard-plastered room with raised, carpeted floors.  What there is of LF has some redeeming qualities, but nothing serious yet.  I am a hopeful guy, and I still believe I can tweak my way toward a more loaded room; but I am not where I'd like to be, with plenty of power to burn.

As we have discussed, much can be done with a raised floor if there is underfloor access and a way to solidly shore up the floor from the ground under it.  OTOH, the classic yuppie "apartment", with raised, carpeted floors and high, vaulted ceilings (volume!), and no way to shore up the floors, is the ultimate energy sink.

I am not sure from the little reading I have done on the subject, but I think there is a whole school of followers that aim the speakers directly at their ears and they do not try to load the room.  Duddleston (sp?), Geddes and some others, I think, might have some ideas for people who cannot or do not want to load their rooms.  I have no serious idea how they would do LF.  If I had to guess, I would guess biased plate amps or similar exponential power schemes.

Paul S

An interesting post, Paul, thanks. It looks like my fear or bass loading of this room were not accidental. If I get this room then it would be even worse in my case. Your have solid slab floor –something that I would like to have. But this house does not have it. What it has is 1700sq feet basement under it as shitty floor with holes in the listening room. I perfectly understand the frustration of the people who would love to pump that space of neat 3400 sq foot from a pair of speaker with imbedded bass drivers. Would it be big Wilsons of small monitors with yellow driver is irrelevant. There is in that my perspective house some feature that kind of unique and made me really like it. This front wall behind the speakers is very easy removable and the room can be easily reconfigurable into “no back wall” type of the configuration. So, we are taking about truly near infinite bass loading scenario… I did not play with it a lot but I certainly would not attack the problem with driving my bass horns lower as some idiots do (The Oswald Mill idiot with his repulsive bass would the first who come to my mind).

So, I think with a proper dedicated LF modules and enough power of amplification this space might be handled. The house has a lot of hidden positive moments for bass enforcement that I have recognized and a lot of bad things for the same bass task. How all those bad and good things will work all together is very hard to say. I would like to see the faces of those people when I ring LF speaker with real-time analyzer to the home inspection….

Anyhow, I have a good feeling about this one. I do not know if I get good sound in there but this room is very inspiring for me canvas to replicate my sound but in larger scale and more comfortable listening. Let see how it goes….

Ok, I do officially like this “Battle Road” hours. Upon many considerations (and there are 4 ways to implement the midbass horn in that room) I have inclined to my leading idea to do it elegant and with time alignment.  The drawing below and a above are way out right proportion and dimensions are by my visual assessment. Still the idea is there.  I am considering to put two straight, irregular pentagon  or heptagon shaped, 12’-13’, Hypobaric 0.7, 45Hz horns in the attic of the house and to have the mouths to fire into the bid room. This will kill with one hit the following objectives:

1)      Not notable in the room

2)      Time-alignable

3)      Not direct radiation and allowing wave maturation

4)      Do not destroy property too much

5)      Kill the fist reflection for the MF channels

6)      Elegant.

I do see in this a tremendous opportunity.

Yep, you were close. The listening room is looking right to the conservation land, in the middle of which there was the original Battle Road. So, that proverbial “shot that was heard around the world” was fired some in the backyard of that house.

http://www.woburnhistoricalsociety.com/images/buildingsandsites/battleroad.htm

I was talking with city hall’s housing authority and was inquiring about any perspective lend development and I was told that this conservation land is dead-untouchable. They told however that sometimes they have minutemen reenactment in the conservation - I afraid that it will be where I was planning to install my antenna tower. If I get the house then I would need to register as a republican and apply to a license to put some landmines around my antenna tower. If any of those minutemen will interfere with my Bruckner then I will start a second American Revolution...