View Full Version : L Pad Settings

08-18-2006, 09:03 PM
I hope this question is not as stupid as it sounds. In his astonishingly useful post about improving the 4345, 250Ti and by inference other similarly equiped JBL's, Greg Timbers said to junk the L Pads and substitute resistors of the working value determined by setup.

Reality One: I haven't gotten around to it yet and can not very soon.

Reality Two: I would like to do what I can at no cost and minimal effort right now.

So...does it make sense to turn down (to the plus dB direction - less resistance) the pads to the lowest balanced settings? Since the speakers are bi-amped, to compensate I need only turn up the power amp for the low pass. Lord knows I have enough power to do that. Would taking most of the resistance out of the circuit lessen the negative sonic effects of having the pads in the circuit in the first place? I know I should have studied how L-pads are wired first, but after asking as many dumb questions as I have, I'm not shy about it any more.:D

In fact, what sense does padding down the entire high pass make in a bi-amped system? None, I would think.

Clark in Peoria

08-18-2006, 10:07 PM
Turning the L-Pads to their lowest-resistance position effectively takes the resistive elements out of the circuit.

The contact resistance of the wiper on the end terminals remains, however. Dirt or oxidation there may be just as problematic.

08-18-2006, 11:01 PM
Thanks, Zilch, you are right. Is is a half-assed fix. But at least I won't be wasting three dB of my amp output just heating up resistance. For that alone, I'll do it until I get off my butt and do it right. Am I correct that there is no reason to pad down the entire top relative to the bottom when it has a different amp?

Also, is shorting across the pads that need no resistance to balance the response good enough or do they need to be disconnected? Wow, this is also a great opportunity to upgrade the internal wire stock. Any suggestions as to wire type (solid or stranded, shielded or not, gauge)?