Poo Poo Tweeters

[Sillyboy]

So, I put some Infinity Reference 6010cs components in my Prius. My trauma is that even w/ the built in crossover set to -3db, the tweeters are (pick any 2-4) harsh/overly-aggressive/painful/poo-poo.

The woofer is down by my calf, the tweeter is up higher -- uh, not sure what you would call that area, maybe "sail panel" ? Sorta above my left air vent -- bottom line: much closer to my ear than the woofer.

After much googling, apparently an l-pad can save the day (http://www.termpro.com/articles/faders.html (see last section))

Questions:
- 8 ohm seems to be the only thing available at parts express http://www.partsexpress.com/pe/showd...number=260-262 Regardless, how do I know if 8 ohm is appropriate?

- from what I read, 2 resistors (one in series, one in parellel) is "the same" as a fixed value l-pad? Could I be cheap and use an appropriate pair of resistors to give a 6db drop (giving me 3, 6 and 9db possiblities when combined w/ the built in xover)? Probably not worth the trouble vs money for real l-pads, but I had to ask

Thanks for any input.
-Silly.
--
edit: if not obvious, I sorta assumed the term l-pad always implied a variable l-pad. After further reading I am using the term a bit wrong

[Sonusthree]

Originally posted by Sillyboy
Could I be cheap and use an appropriate pair of resistors to give a 6db drop (giving me 3, 6 and 9db possiblities when combined w/ the built in xover)? Probably not worth the trouble vs money for real l-pads, but I had to ask

Hi Sillyboy,
Yes, that is possible but make sure you use resistors with appropriate power ratings (Watts) or they will burn out!!!!!

Here's a useful calculator: http://www.lalena.com/Audio/Calculator/LPad/

Hopefully an L- Pad is all you need!

PS: Are your tweeters powered by a separate amp? In this case it would be much easier to use a line level L-Pad,

[Sillyboy]

Thanks for the reply Sonusthree,

Somebody give me a hint on the requires watts for the resistors -- cuz though the "set" rated at 90w, I have a hard time imaging the tweeter actually handles that much

This component set comes with a passive crossover for the woofers in the door and these tweeters.

Linky: http://www.crutchfield.com/S-GW7wLc1...sp?i=1086010CS

I believe the "set" is 4 ohm, but I am not sure how to know what the impedance of the tweeter is. mostly cuz impedance vs resistance is too much for my small brain I assume I can't just use my multi meter to measure it...

[Eric Baker]

Typically, component speaker systems are comprised of a 4-ohm woofer and 4-ohm tweeter, with the crossover networks combining them into a 4-ohm total load. And yes you can measure them with a multi-maeter, just make sure at least one lead is disconnected from the source(crossover in this case) or the reading will be wrong. And yes I know what you mean about the Infinity tweaters being too bright. Probably the only downside of them, aside from being power hungry.

[sr20dem0n]

You can measure the resistance with a multimeter, not the impedance. The resistance of a speaker is typically about 80% of the nominal impedance, so if you multiply the value you read by about 1.25 you should get something close to the usual 4, 6, or 8 ohms, and that's what you would use.

About the power question, 10 watts would probably be fine, but if you want to be on the safe side 20 would work. You also want to use non-inductive resistors.

[y8s]

Originally posted by Sillyboy
The woofer is down by my calf, the tweeter is up higher -- uh, not sure what you would call that area, maybe "sail panel" ? Sorta above my left air vent -- bottom line: much closer to my ear than the woofer.

That sail panel is known as the "A pillar". There's also a B pillar (not always present, can be more than one) and a C pillar where the side meets the rear glass (disappears with convertible top down, also provides large blind spots).

It's likely that the woofer by your leg is losing loudness based on both distance and obstruction.

The L-Pads will work great.

[Sillyboy]

Resistors are ordered -- using the bold assumption that the tweeters are 4 ohm, I got 2 + 4 ohm resistors to give a 6db drop.

Combined with the 0 or 3db adjustment at the cross over, that gives me 3,6 or 9db adjustments (my money is on 9db), which hopefully works out. If not.. hell, it was under 10 bucks.. shipped

And if the tweeters end up being 6 or 8 ohm... well, it wast still just $10 I don't have a feel for what will happen in that case, but... it almost can't be worse that what I have today...

I realize I should have tried to measure it first, but I didn't feel like taking it apart twice (once for measuring, once after the stuff arrives) -- I like living on the edge!

[troystg]

You can also put a single resistor in series BEFORE the cap in the crossover. That will drop the overall level going to the hi-pass cross-over without affecting the impedance of the filter or tweeter.

If the x-over is 2 way @ 12 db there should be a cap and a coil setting the high pass freq. and then the resistors and switch setting the level.

A simple resistor in front of the high pass will drop the level feeding that portion of the cross-over.

[Cal Weldon]

Originally posted by troystg
That will drop the overall level going to the hi-pass cross-over without affecting the impedance of the filter or tweeter.

Are you sure of that?

[troystg]

Sorry for the poor attempt at a drawing.

It DOES affect the over-all circuit impedance, but not the hi-pass or driver impedance.