View Full Version : 400 to 200hz, could it be too much power?

05-23-2005, 07:50 PM
I want to try crossing my 4' dash mounted drivers from 450hz (estimated) down to 250hz. My installer is saying that it could be too much for the drivers. (Infinity 4" driven by a 35WxCh amp)

What do you say?

I'm looking for better SQ. The drivers are too close to the listener (me) and they are sounding a bit "empty". Playing the 6,5s mounted at the doors up to 450hz, ruins the stage.

Could this work?

05-23-2005, 08:04 PM
If any normal 4" driver can't handle 100hz, something is wrong. 250 would hurt a tweeter, but not any normal 4" driver.

05-23-2005, 08:16 PM
My installer said: one octave down, doubles the power that the driver has to handle.
?? is this right?

05-23-2005, 08:49 PM
I don't think so. Amps are tested at 1000hz, and don't magically start sending double power at 500 hz. At that rate your 35 watt amp is going to give to send over 500 watts at 50hz. That's just not true.

If you like, I have some Clarion 4" Coaxials I could sell you. They can take 35 watts like it was nothin', and could easily take an 80hz crossover.. $30 shipped for the pair, PM me.

05-24-2005, 07:01 AM
One octave down = Twice the excursion to maintain the same output ...

Generally, excursion doubles, but I highly doubt you're coming anywhere near Xmax @ 400 Hz anyways ...

The Infinity Reference has a frequency response rating of 85-21000 Hz ...

This makes sense to me... double excursion to play that octave down at the SAME power output.

Now the question is how much could this driver can handle. It is a 4" driver from an old Infinity Kappa CS1-A set (Emitt ribbon tweeters, 4" + 6x9 midbass).
I believe the set is rated 50w RMSbut it has pretty high sensibility.

My real intention is running they active.

05-24-2005, 01:02 PM
Oh, didn't see they were infinity, I thought he meant stock. =p Ignore my attempt to sell coaxials.