3 Attachment(s)
2311 & 2308 & 2441 into 4333
Quote:
Originally Posted by
subwoof
But you cannot change the laws of physics - shorter horns mean higher crossover points...period. Does not matter the size / material of diaphram, type magnet, color of paint or whatever slope the designer of the **SYSTEM** used for the transitions... short horn is a short horn. Be it conical, exponential, hyperbolic, CD, radial, bi-radial, wood/glass/kangaroo dung/unobtanium, sold from radio shack ( RIP ) or a high end boutique with signed papers, hand-buffed edges and speaks japanese. short horn is a short horn. sub
Hi subwoof,
Interesting explanations. Does that mean that any type of horn would have almost the same characteristics, and ONLY the length of the horn is important. If it that would be the truth the easier would be to put the pipe of the desired length. In such situation the if the length of the mentioned pipe (Lp) is equal Lp=Lambda/4, so Lambda=4*Lp, owing to the strong interference of the reflected wave cancellation would happen at the frequencies = (2k+1)*Co/Lambda ( k=0,1,2,.... ; Co speed of sound in the air, about 345m/s), and a kind of maximum would be at= 2k*Co/Lambda.
In the case of 2311 horn (including driver's internal horn of about 7cm) approximately Lambda/4= 17cm, so Lambda=4*0.17m = 0.68cm, that would correspond to about f=500Hz, second minimum would be expected around 1500Hz, etc. So using the driver&horn combo would not be good to be used under mentioned 500Hz frequency.
Using "HORN-RESP" calculator applying about 10W (12,6Veff) about 115dB/1m can be get, while diaphragm displacement would not be more then 0.2mm from the mentioned (500Hz) frequency (everything without applying high-pass filter, that has to be used, as mentioned on the 3133A network, -6dB is around 800Hz, the voltage on that frequency is reduced twice, relative to say 3kHz). As I have remembered (for JBL 244x drivers ) 0.5mm is a kind of diaphragm maximum displacement allowed.
All-in-all I think that 2311+2308 with appropriated driver such as JBL 2440/41/45/46/50 can be used, even in 4333 system.
Interestingly, using longer horn (while keeping the same mouth size) diaphragm displacement over 500Hz remains almost the same.
To be honest, I only know "Karlson coupler" type of 'horn' that is almost pipe-like (with the appropriated long slot), but it seems that such solution is not widely accepted.
http://www.diyaudio.com/forums/full-...n-coupler.html
Mr. John Karson patent US 3445852A has been an 'inspiration' for making Karlson-Couler, but not to forget Adolph Boehmen "SPRINKLER" patent US538861
[ http://www.google.com/patents/US538861 ] from the year 1895 ( May 7 ).
Some more theoretical explanation about Karslon coupler in acoustic can be find in:
http://www.cameng.com/pdf/the_k-coup...ransformer.pdf
I am aware that all above is just an approximation, but I believe that may be useful.
Regards
Ivica