Posted by Lew on March 12, 2004 at 09:28:33:
In Reply to: Re: i got miracles posted by HPFISH10 on March 10, 2004 at 10:27:03:
Sorry for the confusion. The brilliance control is in essence a variable resistor, but it is not
necessary for proper function of the cross-over built into the backplate; it reduces the drive to
the toroidal transformer by placing a resistance in series with the primary. You can take it out
and throw it away, if you can deal with the resulting tonal balance of the speakers. Some folks
have found that they prefer the tonal balance when the Brilliance control is cranked up a bit. For
those individuals, the actual resistance across the Brilliance control pot at its preferred setting
could be measured with an ohmmeter, and then the Brilliance control can be replaced by a
simple power resistor of the value determined by that measurement. Although almost any power
resistor will be an improvement upon the Brilliance control, the kind of resistor chosen WILL have
a subtle effect on sonics, too. (Everything counts; these are very revealing transducers.) Rhyno
on the other hand is talking about the resistor that forms an essential element of the hi-pass
filter (i.e., cross-over) that precedes the toroid. This filter blocks low frequencies from entering
the toroid, which would otherwise saturate it and cause distortion. The low frequency cut-off
point is determined by the values of the resistor and capacitor that form this filter. THAT
resistor IS absolutely essential for proper function of the speakers. Matt Rogers made the
startling finding that sound quality is not only affected by the quality of the resistor used in the
filter but also by its power handling capacity. This has since been confirmed by others, and Roy
Whippey has made super-power resistors for use in the cross-over. The quality of the capacitor
in the hi-pass filter is also a major determinant of sound quality. Some folks like Jenser paper-
in-oil caps; some like film & foil caps (e.g., polypropylene or polystyrene types).