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It's your system,...

and no one should tell you how to set it up, least of all me. But apart from the fact that without the dbx you do need a passive crossover, I still see problems here, assuming that THIS diagram does represent your set-up.

First of all, as far as I can see, you have no hi-pass filter at all in front of the SL toroidal treble transformer. Without the dbx, you need one. If the treble sounds closed in and dark, perhaps this is part of the cause. The toroid will be severely compromised by unfiltered low frequencies coming through the Wolcott. This, I am sure, Dr. West would not feel good about.

Second, what I said before still goes; the impedance of the "back ribbons" will dominate the total impedance seen by the Wolcott. So, whatever is the impedance v frequency of the back ribbons will be seen in parallel with everything else, and the net impedance seen by the Wolcott will be lower than that maximum value. I am pretty sure this would compromise the performance of the Wolcott. I guess you are getting away with that ok, if the crossover does function properly as a hi-pass filter starting at 12kHz, so the impedance problems I have outlined only apply at very hf where there is not much energy demand, but the problem with no hi-pass filter in front of the treble transformer of the SL still stands.

I don't mean to sound dictatorial; I am just trying to help. Will would have told you the same thing, maybe in stronger terms.

My advice: Take the ribbons out of this system for a moment and add a 22uF capacitor in series with the input to the SL treble transformer. That's all. Nothing else but Wolcott to 22uF cap to toroid. Remove for a moment the "12db"crossover and the L pad, as well as the ribbons, front and rear. I guess you can continue to drive the bass transformer full range with the Spectron. The SL bass transformer poops out above 2kHz, anyway. Have a listen.


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  • It's your system,... - Lew 20:29:50 05/11/14 (0)

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