The biggest effect of the HDLs is to eliminate hash in the upper frequencies, so it would make most sense to put them on the tweeter in a bi-wired setup.
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Walker HDL in bi-wiring set up. Woofer or tweeter?
Proac Reference 8 Signatures bi-wired powered by Cary CAD 300 SE, through Speltz's zero boxes set at 1.4X (impedance at around 11 ohm nominal). IF I want to insert Walker's HDL, should I do it at the tweeter or mid-woofer? I know I should use 2 sets for bi-wired speakers, but just want to try 1 set first. Thanks in advance.