Capacitor Biasing in Crossovers

**mah** · March 7th, 2009, 01:42 AM

It appears that JBL has applied DC biasing to crossovers in high end consumer speakers sold in Japan. I tried to find a technical paper on the subject but could only find the usual recycled hearsay or revellations regarding yet another great leap forward posted on various forums.

Is there a serious look at this subject available?

Cheers, Marshall.

p.s. whilst Googling this topic I came across a convert who also DC biases audio cables in order to "stabilise the dielectric".

**bfish** · March 7th, 2009, 09:41 AM

One of the more in-depth JBL explanations of the CC method can be found in pages 10 thru 12 here;

1993 K2-S5500

**bowtie427ss** · March 7th, 2009, 09:49 AM

Yuck! A "monster" plug in JBL literature, wonder if they had to sue to get that too.

**bfish** · March 7th, 2009, 10:05 AM

Consider the context; 1993 sales literature.

**bfish** · March 7th, 2009, 11:01 AM

I have a tendency to disregard any technical explanation that contradicts the basics, such as "Current flows through the capacitor..." As anyone with even elementary electronics knows, no current flows through any capacitor, save for an infantessimally small leakage current. In this case though, I suppose I should heed my own advice;

Originally Posted by bfish

Consider the context; 1993 sales literature.

GM · March 7th, 2009, 04:23 PM

OK, time to show my ignorance...... Sadly, I have zero formal education on the subject, only some technical references I consider beyond reproach that in my ignorance I could very easily be misinterpreting, so by leakage current, are you referring to the cap's conductance due to the electrical circuit's capacitive reactance WRT frequency or......?

I've always taken for granted that 'conductance' means just that, (current/whatever) flow that can be a considerable percentage of the whole in a tweeter's XO BW if I'm understanding what I'm reading correctly.

GM