|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
173.181.24.60
after years of simply believing that in a room with an 8 ft ceiling that a horn with a 90Hx40W dispersion was about optimum and that round horns were going to cause serious problems with ceiling and floor bounce I find that with four different horns that I have set up in my room that I consistently prefer having the narrow dispersion in the horizontal plane. This is leading me to suspect that a round tight pattern horn might be the best way to go.
I also have found that the old adage of bigger is better to hold true. Given my very non scientific experiments with a number of horns in a two way CD set up the larger horns sounds better. If I take a smaller horn and extend the mouth to roughly the same dimensions as the larger horn the smaller horn sounds pretty much like the larger one. So now I am wondering about a couple of things how much dispersion do I need / want? and what shape horn mouth makes the most sense?
I am wondering if any of the members here have ever experimented with horns with square mouths and round mouths with similar cut off and dispersion. If so what did you think. Like wise I am interested to get peoples impressions on comparisons between tighter Vs wider dispersion horns with similar cut off freq.
I find myself now thinking that a conical CD horn is much more attractive than I have previously thought. Trying to shed my preconceived notions and would appreciate the input of those who have been there and done that so to speak. Thanks Best regards Moray James.
moray james
Follow Ups:
"Acoustic Waveguides - In Practice", P.D. Bauman, A.B. Adamson, & E.R.
Geddes, -- JAES, Vol. 41, No. 6, 1993, pp. 462-xxx.
200hz~2Khz and 2Khz on up.
Made in Canada.
Look here: (see attached link)
Dave offers many direct replacements for Klipsch horns, and will make custom sizes and shapes. He's a nice guy as well.
Br3098: thanks for the post and the link. I think it fair to predict that an elliptical horn will be similar to a rectangular horn in that it will have tw0 primary dispersion angles no? I would think the elliptical horn would have a smoother transition. I was more interested in finding out what difference if any a square mouth would have Vs a round mouth with both horns having the same angle of dispersion. The Square horn would be a little lager in mouth are due to the corners. From the feedback so far it seems that there would not be much if any difference. Thanks again. Best regards Moray James.
moray james
Moray James,
I met with Dave at his home on Saturday night to listen to his new Yield speakers. He builds his own horns, both square and elliptical, so I would bet that he could build you whatever size you want. The elliptical horns are designed to attenuate certain problems with limited room sizes and boundary issues.
Dave is a great guy. Shoot him a not and engage him in a discussion. I'm sure that you will get a quick, intelligent answer. BTW - as Norman has mentioned Dave is all over the Klipsch forum.
Best Regards
Thanks for the post and sorry for the delay in responding. I think that shipping the size of horn I would like would get too expensive. I would like to have a horn somewhere in the range of 24 - 28 inches in diameter. Best regards Moray James.
moray james
That's the one. Do a search on the klipsch forum.
Norman
Norman: thanks. I am pretty sure that Dave does not build horns as large as I would like to go and even if he did the shipping would be insane. I am on my own here looking for large local used speakers or building myself. I saw a pair of Peavey CH-942qt the other day which looked interesting 17.5"x13.5". They looked very nice wish they were even larger. I have been wondering about buying a used horn with the throat geometry I could use and then chopping off the too small mouth and building on a new larger mouth. Has anybody here done this? Thanks, best regards Moray James.
moray james
$289 free shipping, jbl 2418h plus 2374 horn, 14 day return policy. Too bad You can't put a larger driver on the horn. Maybe a real shop could, then you could cross maybe 600hz.
not related to me, not my stuff for sale. Just something I've been keeping my eye on.
Edits: 05/14/12 05/14/12
In actual listening tests I find little difference between square horns of the same side wall angle as a round horn.
Square or rectangular horns are far easier to build than round horns, and have the advantage of easily designing the horn for the horizontal and vertical dispersion pattern desired for a particular listing environment.
My personal preference for a horn pattern for home use would be one that covers the "critical listening" area of the couch, and little else.
That said, a horn with mouth dimensions that would provide that pattern to around 500 Hz would require a depth and mouth height unacceptable to me in the rather small home theater I have.
thank you Art, I appreciate the comments. This is more or less where I was going with all of this. I like the idea of the horns covering the main listening area only to as low a frequency as possible. I would at a guess figure that I would need a horn 26 -30 Inches square at the mouth and likely a metre deep if the angle were 40 degrees.
Yes I agree that size is getting very large to deal with. That is where the age old compromise comes into play. There is always a gotcha moment in every project where compromise was not considered from the outset. I am in an an apartment so some compromise will be necessary. So now I have some rough dimensions to work with. This sounds like a job for the CNC controlled router machine. Male a roundish horn with biscuits to align everything up and make assembly much easier. Will have to make some calls ad find out how much having the parts machined up would cost. Thanks again. best regards Moray James.
moray james
Edits: 05/09/12
Conical horns are easy to build, and many DIY guys have built excellent Unity/Synergy style horns with standard hand tools.
A Synergy horn has the advantage of a single point source from a single horn using multiple drivers covering a wide range, which reduces the system size considerably while also increasing coherency, especially if one is constrained to a close listening distance.
Unlike separate horn units, which require some distance back to integrate, you can literally stick your head in a Synergy and it sounds the same as it does some distance back.
Like any horn, the tighter the dispersion, the larger it must be for a given cut off frequency. That said, by combining relatively high bass reflex porting with the Synergy horn, a relatively compact enclosure can reach low enough to just need assistance below 50-100 Hz.
This makes placement of the sub almost a non issue, as the sound will not be localized to the sub in a small room.
If I were building a horn system for domestic listening, it would be a Synergy style horn. My living room is still too small for them, but I have plans for my deck..
I was busy thinking about the visual esthetic and round being smaller to look at for a given mouth dimension. It has occurred to me that there may be some small advantage to a square mouth in that you will have a longer dimension to the corners. Is that going to count for much? I am thinking probably not but I have no practical experience with this. Anybody have any comments? A multi sided round horn is going to have an advantage over a square flat sided horn, with the round horn having greater structural integrity. Best regards Moray James.
moray james
here is a jbl 2374 horn.
well, I can only tell you what I've heard. The klipsch guys are loving the wood kit, less expensive if you assemble the slices and sand.The stuff I know. Corners are bad. Parallel walls (especially at the throat) are bad. Slots at the throat are bad. A bend would help (throat to mouth, jbl 2374), unlike a straight conical (reflection bounce mouth to throat), or a horn that breaks (like altec manta-ray). And ideally the mouth folds all the way back to the baffle (like a le'cleach or the jabo / stereo-lab horns).
These Horns I've not heard, but based on the criteria above, I'd like the gedde's oblate spheroid. I'd like the peavey quadratic horn. I'd like the jbl 2374 (but too big a horn for that compression driver's wave plane response) and the 2384 (me want). I'd like stereo-labs (but need more dispersion than the tractrix can give me when crossing at 750hz). I'd like the avante-garde (same tractrix lack of dispersion past a decade). I like the le'cleach (exponential, even less dispersion). I'd like the 18sound 1464. And better ears than mine like the jbl 2344.
But if you measured a horn, you'd see standing waves (impedence spikes) for the distance throat to mouth and also across the mouth. A rectangular or elliptical mouth would have 2 smaller mouth standing waves (to me) compared to a circular mouth.
But I am pleased as punch with my high end boosted ev hr90 with foam covering 1 of the parallel walls in the throat and foam at sides. Then again, I'm also running from 750hz to maybe 15khz (more than a decade), so I need the 90 degree horizontal dispersion that my cd-horn gives me, especially because I'm only using 1 speaker for the entire room.
Norman
Edits: 05/10/12 05/10/12
Norman: I have only just made the connection that you may have been referring to these horns and a link which was kindly posted by another member. I had not thought of these as I did not think that Dave sold the parts as a kit. Is this what you were referring to in your post? Thanks best regards Moray James.
moray james
Norman: can you elaborate on the wood kit that you referred too? I would also be interested to hear what you have done to your HR90 and would like to see any pictures that you may have of the felt and foam application. Thanks for posting. Best regards Moray James.
moray james
I'll get back to you on the kit.
Notice foam down in the throat. Big improvement, removed the "live sound" that isn't supposed to be there (headphones). But I really had to boost the highs to make up for it.
Norman
Thanks Norman that picture is very clear to see exactly what you have done. I have played with some 30 ppi foam in the throat section you might try a thin slice of that to break up the modes and get away with less HF boost. I had a block of 30 ppi foam in the whole are that you have you foam in (parallel section at throat) I replaced that with some 30 ppi in the conical throat section of the horn I also have some in the comp driver. thank you and I will be interested to find out more about the horn kit you mentioned.
You might want to try aligning the top plate of your comp driver with the top plate of your woofer. I have found that in my room 8' high I prefer the horn to have its narrowest dispersion in the horizontal plane. Give that a try and see what you think. Best regards Moray James.
moray james
to you on the kit.
Ideally, yess the woofer and comp magnets would be exact, but I only have to be 1/4 wavelength plus/minus at 750hz, and the 15" magnet is deep, and it will only be lined up at 750hz, so the alignment is moot.
I actually enjoy the wide dispersion horn. I need it to be room filling (not listening in stereo). And I like the penetration of the mids/highs in the back of the room.
Someday I'll try some of that foam, but I'm happy for now, at least until I can get the horn I want to try.
Norman
The Peavey CH-1 is based on the EV HR-90, since it was designed by a couple of EV Engineers that defected...........same with the 22A driver for it.
Thanks Claude: that is interesting I did not know about the 22A. The 22A is a very nice driver. With a one piece aluminum alloy diaphragm/former the entire diaphragm becomes a heat sink for the VC and you have zero issues with energy transfer between the former and the diaphragm. If they had made a metal phase plug and anodized everything black they could have realize significant increase in thermal dissipation The Mylar surround was very much ahead of its time also. Very nice piece. Best regards Moray James.
moray james
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: