JBL e120 in midbass horn application

[ivica]

I will be removing the alum dome completely. It will be replaced with a big phase plug to reduce the on axis beaming.



Because of this the 6 db/octave low pass filter will work very well and predictably, to integrate with my midrange horn.

Herman

Take care about E120, because it's voice coil length is shorter ( I think in order to enlarge 2'nd harmonic, to 'improve' guitar sound, or to say: music "production") then 2202 (which is much more liner,and i think better for music "reproduction").
I have no idea about the membrane strength concerning its 'loading' because of 'phase plug' applied.

[more10]

http://www.audioheritage.org/vbullet...l=1#post320687

Figure 2C. E120 has an "equal height coil and gap". This is what Ivica is talking about I believe. In a horn the cone will not move much. Maybe not a problem?

Very smart thing to attach a phase plug to the pole piece. What material will you use? Will yop glue it to the pole piece?

[Herman Chigrin]

The e120 and 2202h have different magnet depth. So what happens if I re-cone e120 with 2202h cone?

As far as the phase plug goes:
If the e120 pole piece has a hole in the center I can mount the phase plug to the pole with a screw and a washer. The washer will be at the back of the magnet (covering the vent on the back, the screw will go through the pole piece exiting at the front and attaching to the phase plug.

[jerv]

This is very interesting.
I am also contemplating a midbass horn.
How do you make the horn and phaseplug?

[more10]

Loudspeaker Power Handling Vs. Efficiency. It might seem that plugging the vent is a bad idea. But if you turn the phase plug into a heatsink, it might improve the driver considerably. A phase plug made of aluminium will be quite heavy though. If you make a straight horn you will have natural convection in the horn as well.

This is definately something I will try myself.

[Herman Chigrin]

http://www.funktion-one.com/products/resolution-3-sh/

Look at the midrange section, it uses a 10" mid. The idea is to keep this concept but adapt to the 100Hz horn with 12" driver.



Also see this 15" midbass horn.
http://www.funktion-one.com/products/ds15/

my version would be something between the 10" and the 15". You guessed it, 12" midbass!!!


Herman

[more10]

I have done some simulations using 2202, E120 and PD.121. They all perform very similar in a horn optimized by hornresp. What varies are the compression factors and horn lengths.

I have used fs=68 to get the first acoustical impedance minimum at 100 Hz, making the horn useable from 100.

Driver compression length
E120 4.22:1 189 cm
2202H 3.4:1 190 cm
PD.121 5.17:1 203 cm

The biggest problem with this kind of horn is the beaming. At 0 degrees the response rises 9 dB from 100 to 400 hz.