Radian 835PB Experiment

I am a heretic and don't really care about convention, but I do love to experiment. Maybe it works, or maybe something nice gets ruined in the name of science... but why not try some ideas and have fun?

Have a pair of Radian 835PBs, stock diaphragms, prefer them over nearly every other comp driver. Smooth, vibrant and not painful but they never stay in a system long term and I wanted to find out why.

For day to day listening I use a pair of 48" Newform ribbon drivers - not perfect but they do many things right and require very little work to integrate with anything using a simple first order x-over. Recently comparing the Radians to the ribbons it was immediately obvious the Radians had a metallic "color" that was overlaid on everything. Subtle (compared to other "big personality" drivers like JBL) and sometimes pleasing but there. On EVERYTHING.

I pulled off the back caps and removed the diaphrams. Very gently rubbing the diaphragm with my finger - there it was! The metallic sound.

With a deep breath, I then applied a VERY thin layer of Carmex lip balm on the entire diaphragm surface (The side that fires into the cap, not the side that faces the phase plug!) Also applied 4 dots on the suspension spaced evenly. Second finger rub test and virtually ALL of the metallic sound GONE.

Put the drivers back together. Will this be a revelation? Will they sound like ****? Will the top octave disappear?

To my relief, the drivers sounded incredible. Their timbre almost exactly matched the ribbons and the metallic color was GONE. Top octave was still there but much less "noisy" if that makes sense? I'll assume the very thin layer of "goop" was no challenge to the enormous magnet structure on that driver.

If the experiment was a bust, then it would be easy to reverse but the Carmex will stay on this pair. Thought it was worth sharing.

Cheers! -Pat
 
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Radian 835pb

Was the metallic sound you describe throughout the entire frequency range of the driver or was it just in the upper frequencies??? I have been wanting to try the 1.4" 835pb for a while but i am going to use them from 800hz to 8000khz. My altec 802's had something similar to what your describing i took the loading caps off and they sounded. Great maybe the sound your describing was sound from the diaphragm radiating of the back cover? Maybe the wax is deadlining the sound coming from the backside of the diaphragm? I made a new cap for my 802's out of wood about three times larger than stock lined with 1/2 foam sounds great to my ears and was easy & inexpensive to make.

So what do you think about the Radian 835pb compared to other drivers? I have heard a few people say they prefer Radian to TAD or JBL. If they are as good as what a few people have claimed then in their price range they would be a great buy.
 
Sean, without lining up drivers on the table and comparing them A/B/C I dont know how to answer your question. But, after the damping they had the same timbre as the ribbon drivers vs before when they had that "sheen" typical of aluminum dia comp drivers. To be fair, that sheen doesn't sound bad and does add a certain "sparkle" to the sound but its not in the original signal and to my ears does more harm than good. The sense of "open and spacious" was tremendously better after the damping.

It would be a fun experiment to try with big JBL's like the 2446 as they might also sound amazing with the diaphragm resonances under control.