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kawasakitech
01-20-2013, 02:59 PM
Hi


I have Lowther EX-2 drivers in back horn loaded cabinets and really like them but dislike the limited bandwidth.
I also have JBL 2220 drivers in 7.6 cu ft cabinets in a 6th order equalized vented alignment and Altec-Lansing 811B horns with 808-8A drivers, these are bi-amped and very clear and dynamic.
I do not drive them very hard , usually about 1/10th of a watt as it gets very loud in a relatively small listening room.
Also distortion is less at a realistic listening level and there is less tendency to go deaf.
The JBL/Altec speakers are much more forgiving of recording quality than the Lowthers. More music is enjoyable to me.
I have retired the Lowthers but would like a bit more low bass from the JBL/Altec combo.
Both bass drivers are similar in construction in that they are low Q, high efficiency, light cone assembly with large magnets (cq over-damped).
I originally built the cabinets for JBL 2205 drivers but I didn't like the midrange sound so I went to the 2220s and re tuned the cabinet and filter.
I really like drivers that have this type of sound and have no liking for the modern low efficiency drivers.
I am looking at 18" JBL bass drivers and find that Q values are getting higher and cone weights are also going up where efficiency is going down as they get newer.
The older drivers were more efficient, probably due to less amp power.
Like the E-151, as rare as hens teeth.
Am I right in assessing this much value to low Q drivers or am I barking up a non existent tree?
I just want a little more weight in the bass but am afraid if I go to a newer driver or a less efficient higher Q one it will not integrate with what I have.
I plan to tri-amp and cross over at 100hz and 1.2khz.
I might also add a 2123 mid and crossover at 100hz, 300hz and 1.2khz
I have read Speaker Builder since the early 80's and am amazed/intrigued that there are never articles about large efficient loudspeakers, I guess it's a hard sell to the wives of the world.
I have a dedicated listening space in the basement, GREAT!!!!

Thank you

Bloys Dekker