|
High Efficiency Speaker Asylum Need speakers that can rock with just one watt? You found da place. |
For Sale Ads |
Use this form to submit comments directly to the Asylum moderators for this forum. We're particularly interested in truly outstanding posts that might be added to our FAQs.You may also use this form to provide feedback or to call attention to messages that may be in violation of our content rules.
Original Message
RE: Sure information supplied
Posted by Paul Eizik on February 3, 2017 at 11:49:25:
Pix
A horn is most efficient when the horn length is equal to 1/2 of the wavelength at the lowest target frequency. If the horns pictured here are 600 mm (23 5/8") in length they would fall short of being 200 Hz midrange horns:
13,500/200=67.5/2=33.75", which would be the ideal length for a midrange horn with a low frequency target of 200 Hz.
As a 350 Hz horn it should work as the half wave dimension for 350 Hz is 19.28" which is quite close to the 600mm (23 5/8") length.
Making the horn throat smaller than the 2" driver exit (if I understand your intension) would have the effect of making the volume of the air chamber in front of the driver diaphragm larger, which would have the effect of rolling off some of the high frequencies at some point, and this may be constructive or it may not. This is to say it could be useful rolling off a high frequency peak in the response, or it could just put a dip in the response which may not be useful.
A frequency response test graph would reveal if there is a peak in the response of this horn and driver combination that techniques like this could be used to tune out, but it's difficult to generalize if something like you are proposing would be an improvement or not. Tuning something like this "by ear"can be problematic as you can wind up with something that sounds good with one particular favorite recording, but worse with other types of music, and I've been there and done that.
So this all comes down to Cowboy Engineering: try it and see what happens.
BTW I would avoid a curved adaptor in a midrange horn, as this would assume that the wave front can maintain the same speed between the longer outside radius and shorter inside radius. Also a first order crossover is a good match for a horn where the bass end typically will roll off naturally at a quite steep angle.
I hope all this helps
Paul