View Full Version : JBL L86 woofer excursion

08-11-2015, 04:38 AM
Hi guys!

First of all thank you for having me as a part of your comunity, my name is Dan and I'm from Romania.

I recently bought a pair of L86 speakers which I adore, but I noticed something strange, there is too much woofer excursion. I drive them with a yamaha CR-800, which has 40wpc, and about half way up I can hear the coil grinding (I think). The eq is always flat, and this happens only on some bass heavy tracks. I know these speakers were not made for bass heavy music like electronic and such, which I don't listen that often, and I really wouldn't want to damage them. Also, they were profesionally refoamed, and the guy did a fantastic job, they are perfectly centetred.

So, what could be the problem? Is it just the way they are built ? Am I doing something wrong?

Many thanks!

08-11-2015, 05:22 AM
I have seen excessive diaphragm movement (thus, distortion, including voice coil rubbing sounds) from a loose spider or even a spider which has become unglued on one side, resulting in voice coil alignment issues. I would stop using them, inspect them carefully and run tests to verify that everything is up to snuff before you destroy them. Other than something mechanical going wrong, not much else can cause excessive excursion at moderate listening levels.

08-11-2015, 06:22 AM
I just checked the spiders (which are impressively large), and they are perfectly fine. :blink:

rusty jefferson
08-11-2015, 07:40 AM
Are you using a turntable, or digital source? If you are using a turntable, you may have a mismatch between the cartridge and phono stage. This can cause excessive cone movement when turned up. Also, poor isolation of the tt can do the same. If your source is digital, try a different amplifier.

Lee in Montreal
08-11-2015, 08:18 AM
Activate the "subsonic filter" if using vinyl records as a source. :D

08-11-2015, 08:26 AM
I'm using a macbook with a focusrite external soundcard and a Philips CD104 for my CD's. When I bought the yammie, it had been started three times since the 70's. It has been also looked at and all the numbers say it's ok. I heard something that it's wrong to push an amp with significantly less power then the speakers, but I don't know much about it. Thank you so much for your replys!

08-11-2015, 08:31 AM
Activate the "subsonic filter" if using vinyl records as a source. :D

I played vinyl on it at some point, and used the 70hz cut for all the rumble. It was beautiful, but vinyl is a very expensive hobby for me, as a student. Thanks!