woofer impedance folded horns

[Esoteric]

I have 2 "K" type folded horns with JBL 2205 woofers rated at 16ohms.
I understand that the woofers should be 3.2ohms. Can I place resistors across the woofer terminals ( Pos. to Neg.) to lower the impedance? What values on the resistors do I need?

I am using the LX-5 network ,8ohms, and the 2440 drivers with horn and lens assembly. The LX-5 actually measures
12.5ohms.

[Harvey Gerst]

Uh, that's not a great idea; the resistors would get most of the power and it would just be radiated as heat.

The right answer to the resistor problem would be adding a 4 Ohm resistor in parallel across the 16 Ohm speaker to achieve a 3.2 Ohm load, but it's not the right solution.

The correct solution is to use a different amp that can properly drive the woofer, or recone the speaker to the desired impedance.

[Esoteric]

Uh, that's not a great idea; the resistors would get most of the power and it would just be radiated as heat.

The right answer to the resistor problem would be adding a 4 Ohm resistor in parallel across the 16 Ohm speaker to achieve a 3.2 Ohm load, but it's not the right solution.

The correct solution is to use a different amp that can properly drive the woofer, or recone the speaker to the desired impedance.

Thank you, Harvey for your suggestions.

[Thom]

Uh, that's not a great idea; the resistors would get most of the power and it would just be radiated as heat.

The right answer to the resistor problem would be adding a 4 Ohm resistor in parallel across the 16 Ohm speaker to achieve a 3.2 Ohm load, but it's not the right solution.

The correct solution is to use a different amp that can properly drive the woofer, or recone the speaker to the desired impedance.

If your current amp is able to drive the speaker/enclosure to a level you are happy with then there is no reason for a new amp. Now the only question is does the crossover match the woofer. If it doesnt it can be modified or replaced. If it is looking for 4ohms and sees 16 it will cross much higher. This may or may not be audible as you undoubtedly have a lot of mechanical roll off as well.

It's also possible that it is so efficient that you are using so little power that you actually could parallel it with a power resistor but I would make sure that I had a problem before I started fixing it.

[Esoteric]

Why is that?

Hal Cox suggested that impedance and I think Klipsch used 3.2 drivers.

[scott fitlin]

I think the impedance of the original woofers used was a 4ohm woofer, as 3.2 ohms is the DC resistance, not the impedance. Many 4 ohm woofers of the past would read 3.2 ohms on a meter.

[Esoteric]

I think the impedance of the original woofers used was a 4ohm woofer, as 3.2 ohms is the DC resistance, not the impedance. Many 4 ohm woofers of the past would read 3.2 ohms on a meter.

You're right. My mistake. The woofers were 4ohms. I don't understand why
because my woofers blend nicely with the 2440s, but I just wondered what I was missing if anything. The curse of us hi-fi nuts!

[scott fitlin]

Yeah, but if the crossover networks were designed to see a 4 ohm impedance, you arent getting the correct performance using 16 ohm coils.