Lee are you doing anything WRT time alignment. Also I notice that for exmple you had the 2405 way bck on top of a flt surface. Probably not a good thing. Other than that you are a nutter
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Lee are you doing anything WRT time alignment. Also I notice that for exmple you had the 2405 way bck on top of a flt surface. Probably not a good thing. Other than that you are a nutter
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I have since revised the position and located the 2405 as far back as possible, barely ahead of the medium driver. I will close the back of the medium driver tomorrow. I bought some 6" Sonotube and will make a round sealed enclosure. Probably around 9" deep.
BTW I love the sound of a cone driver mated to a long horn. The L104H- rolls off at 7k, where it is crossed over with the 2405. Great match. And the horns gives it some efficiency and projection. Unusual combo, I know, but it works, while the driver is cheap. ;)
I have been redesigning the 4520 enclosure to accept a pair of 18" drivers. I'd like to regain the tightness of the 4530 which is lost in the 4520, while reaching 15-20 Hz lower.
I checked out the 18" e155 bass instrument speaker. It has an Fs 30Hz (which I expect the new 4520 to be tuned to, and a Qts 0.2 which promises tight bass. What are you thoughts?
Tonight, I removed all four 2225 drivers to inspect them closely. From the front, the cones and suspension have 100% the same texture, glue colour, and glue spread. The felts all around the basket are also 100% identical. It is when I turned them on their face to inspect the back of the cones that the differences became clear.
The good sounding drivers had "2225h" written in big white letters, and a smallish white round "JBL Pro" tag. Not so on the two bad sounding ones. Different textures on the back of the cone, no script, no tag. Gonna have to have a chat with that dude who sold them... ;)
So, I guess it does explain why one 4520 sounded good, and the other was anemic.
the only way to "tune" a folded horn lower is to make it longer - for your goal, a LOT longer. Unlikely you would be able to fit it through any door. The Fs of the driver is mostly irrelevant unless it unloads easily ( ex: 2235 ) when given a signal below the horn's cutoff.
Physics doesn't change.
If you use 2 horns together, placed side by side, they should output a bit more energy in the lower end due to larger exit area.
Ben busy lately. BUt I am purchasing either a NOS C8R2225 and a freshly reconed 2225h, or two god used 2225h with JBL cones. Waiting for prices. Then this summer I will build the 4520s for 18" 2240h drivers. Found a place in the US where they have them for $125 a piece with recent original JBL recones.
Lee
You'll be the first to know. I'll wait until I receive the other drivers.
Actually, I even thought for a moment they might have been 2227 recones in the 2225. The 2225 is known for its superior bottom end. No wonder the 2227 is a mid bass driver rated at 50% extra power if it lacks real 10Hz "down there"...
2227 kits will no way in hell work in 2225 baskets.