BillFitzmaurice.info

I have some off-the-shelf 12db 3.5k high-pass crossovers (Dayton Audio from Parts Express - $7 or so each... cheap but simple stuff.)

I'm in a time bind right now since EVERYTHING i've ordered since last Friday has either been delayed or just flat out not filled completely, which has me in a pickle.
Can I use these crossovers for the tweeters in the SLA Pro (2x6)?

I do have some 30 Ohm and 4 Ohm resistors I could wire into it to make it like the plans, but I don't have the crossovers in front of me as I type this to verify the Cap & Coil values of the pre-rolled crossovers.

My goal is to run the 2x6's with the 4x6's simultaneously if that makes a difference.

Help much appreciated.

Thanks,
Tim

Off the shelf high pass filters will not work with the capacitive load of piezo tweeters. For temporary use you can run the tweeters without a high pass filter, but the 4 ohm resistor must be in place to protect the amp.

Thanks Bill!

Ran with it for rehearsal tonight.
The 4 ohm just inline seemed to really knock the piezos down and tame them very well.
Working great so far.
Thanks again!

The 4 ohm resistor has no effect on the piezo response. The reason for having it is that the impedance of piezos decreases as frequency increases, to well below 1 ohm in the ultrasonic frequencies. That can cause potentially damaging oscillation in an amp that's doesn't have an inductive coupled output to protect it from that possibility. The resistor insures that there will not be less than a 4 ohm load at any frequency.