Horn question.
07-05-2004, 08:09 AM
#11
50 Watt CAFz'r
Join Date: Jan 2004
Posts: 206
Back to the original question......
The idea of a long horn is to give the illusion of the driver being farther away. Unless he cut out the fire wall (like Mark Eldridge has done) to make the speakers sound like they are 5-6 feet away the horn bends up under the dash to give that added length.......thats the theory.
Longer does not mean they play lower. Mouth width, Driver ability play a larger roll in how low they play. Length will add efficency (lower input, gives more output vrs a shorter horn)
Mark Eldridges (from a few years ago) were even longer, and wider.
The idea of a long horn is to give the illusion of the driver being farther away. Unless he cut out the fire wall (like Mark Eldridge has done) to make the speakers sound like they are 5-6 feet away the horn bends up under the dash to give that added length.......thats the theory.
Longer does not mean they play lower. Mouth width, Driver ability play a larger roll in how low they play. Length will add efficency (lower input, gives more output vrs a shorter horn)
Mark Eldridges (from a few years ago) were even longer, and wider.
07-05-2004, 03:07 PM
#12
Guest
Posts: n/a
Originally posted by Impala Builder:
Longer does not mean they play lower. Mouth width, Driver ability play a larger roll in how low they play. Length will add efficency (lower input, gives more output vrs a shorter horn)
Longer does not mean they play lower. Mouth width, Driver ability play a larger roll in how low they play. Length will add efficency (lower input, gives more output vrs a shorter horn)
07-05-2004, 03:55 PM
#13
2000 Watt CAFz'r
Join Date: May 2000
Posts: 2,406
Kilowatt, the size and shape has no bearing on how low the horn will play. That is solely dependant on the driver. The altec that RC and Mark use allow them to play lower then any of the commercially avalible "wave guides" would play. The larger the driver the better the power handling. The size and shape of the horn only has to do with the dispersion of the sound coming off the driver.
Nothing more...........
Nothing more...........
07-05-2004, 04:57 PM
#15
Guest
Posts: n/a
Tim, size (specificaly the mouth size) and shape does play a large role in the ability of the horn to play the lower frequencies, now if the driver itself will not play as low as the horn was designed to play, then of course it isn't worth a hill of beans.
Here's a post where Mark E (since you mentioned his name) vaigly reffers to size vs. low frequency cutoff:
http://www.carsound.com/UBB/ultimate...=022512#000002
Here is a decent website which goes into depth a little about horn designs and has calculations for low frequency cutoff's etc.:
http://melhuish.org/audio/hornshape.html
A couple more websites that reffer to size vs. cutoff:
http://www.speakerplans.com/page93.html
http://www.icmsstephens.com/horns.html
http://www.positive-feedback.com/Iss...rinterview.htm
http://www.lenardaudio.com/education/07_horns.html
I also have an Autosound 2000 Tech paper here which goes into detail about the Veritas design (as an example) and how the rapid flare at the end of the horn alows it to load the driver down to approx. 550Hz (the driver must be capable of playing this low of course).
I am not a horn expert by any means, but I have spent a great deal of time talking to people who do design them, and enjoy working with them. If I am wrong, so be it, I am here to learn.
Here's a post where Mark E (since you mentioned his name) vaigly reffers to size vs. low frequency cutoff:
http://www.carsound.com/UBB/ultimate...=022512#000002
Here is a decent website which goes into depth a little about horn designs and has calculations for low frequency cutoff's etc.:
http://melhuish.org/audio/hornshape.html
A couple more websites that reffer to size vs. cutoff:
http://www.speakerplans.com/page93.html
http://www.icmsstephens.com/horns.html
http://www.positive-feedback.com/Iss...rinterview.htm
http://www.lenardaudio.com/education/07_horns.html
I also have an Autosound 2000 Tech paper here which goes into detail about the Veritas design (as an example) and how the rapid flare at the end of the horn alows it to load the driver down to approx. 550Hz (the driver must be capable of playing this low of course).
I am not a horn expert by any means, but I have spent a great deal of time talking to people who do design them, and enjoy working with them. If I am wrong, so be it, I am here to learn.
07-05-2004, 07:07 PM
#16
I'm not an engineer, I do understand a bit about driver specs and such.
Would I be correct in assuming that I could use just about any driver(ideally the Peerless midranges I have sitting in my basement) To make a set of horns provided I follow the specs provided by any reputable website that discusses the fabrication of horns?
Would I be correct in assuming that I could use just about any driver(ideally the Peerless midranges I have sitting in my basement) To make a set of horns provided I follow the specs provided by any reputable website that discusses the fabrication of horns?
07-05-2004, 08:53 PM
#17
Guest
Posts: n/a
Perhaps I should explain my point a little better than I have above. If you design 2 simple horn lenses, one using a Tractrix curve, and one using an exponential curve, but both with the same mouth area and flair rates, the Tractrix will be shorter in length physicaly due to the higher rate curve profile. So you can see how they all tie in together and one effects the other. The driver must also be able to play the desired frquency, but the horn lense plays a large roll in loading the driver, thus allowing it to play lower frequencies.
07-05-2004, 09:18 PM
#18
By Tractrix curve you mean a "spherical curve"?
I just read some of Avantgarde's technical pages on their horns. They have some excellent literature on there...well explained.
What I also found interesting was what they said about the driver vs driver and horn sensitivity. While a driver may be 87Db efficient, when used in a horn it becomes 97db and actually gains sensetivity. So, when reading the spec sheet for an ID CD2 the driver itself is not 109db efficient, the driver/horn combo is 109 efficient. Very cool. Also begs the question why not in SPL?
My next question.
If a person was to build a midrange horn for home/car whatever. They want a horn that will play all the midrange frequencies. Lets say for example, they need their horns to play from 600hz to 4Khz. Normally, you would use a crossover whether it be passive or active to achieve this. You would still need your crossover on a set of horns, but does the horn have a lot of effect on the roll-off that crossovers allow....lets face it...all crossovers allow roll-off which is why choosing a crossover setting is crucial in an audio set up. I know that adding a horn to a driver adds 10db effiency, but does the lense affect the roll-off? And how so?
I just read some of Avantgarde's technical pages on their horns. They have some excellent literature on there...well explained.
What I also found interesting was what they said about the driver vs driver and horn sensitivity. While a driver may be 87Db efficient, when used in a horn it becomes 97db and actually gains sensetivity. So, when reading the spec sheet for an ID CD2 the driver itself is not 109db efficient, the driver/horn combo is 109 efficient. Very cool. Also begs the question why not in SPL?
My next question.
If a person was to build a midrange horn for home/car whatever. They want a horn that will play all the midrange frequencies. Lets say for example, they need their horns to play from 600hz to 4Khz. Normally, you would use a crossover whether it be passive or active to achieve this. You would still need your crossover on a set of horns, but does the horn have a lot of effect on the roll-off that crossovers allow....lets face it...all crossovers allow roll-off which is why choosing a crossover setting is crucial in an audio set up. I know that adding a horn to a driver adds 10db effiency, but does the lense affect the roll-off? And how so?
07-05-2004, 11:16 PM
#19
I also understand from what I have read that the mouth area to be a determing factor in the lower cut-off frequency of the horn. The throat area, at the driver, being the upper frequency cut-off. And the length of the horn affecting efficiency of it, but that I'm not 100% about.
