Odyssey mod - woofer damping

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spectral

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I decided that the -3dB switch on the Odysseys isn't cutting it, so I set out to attenuate the bass, which ultimately affects the midrange as well. Below is a picture of the prototype showing two 50W resistors (aluminum cased, wire-wound thus inductive) in series totaling 4 ohms. The final version will feature two separate configurations of 4 and 6 ohms, using Caddock resistors (non-inductive) and two sets of Cardas binding posts, to make it easier to experiment with 4 (A) , 6 (B), 10 (A+B) and 2.4 (A in parallel with B) ohm configurations.

Coincidentally, in the November issue of TAS I just got, the Wilson Alexandria review sports pictures of the speaker's back that uses exactly the same Caddock resistors I have on order, with apparently the same functionality for the woofer... These are some amazing resistors...

The result with the current experimental 4 ohm configuration is simply phenomenal, which is why I decided to go to "production" by spending $100 on four resistors, $180 on the binding posts and another $100 on Kimber jumper cables. The impedance changed in such a way that I was able to turn my REL sub DOWN significantly (mind you, the sub is smoothing out major peaks at 40-50Hz by turning it UP - phase interactions - more than it provides the very deep bass) - crossing over at just 23Hz (from 27Hz before) with the volume turned down a few notches from before. The end result is smoother bass from 20Hz to 200 Hz (using Stereophile warble tones), i.e. +-3dB variation from the reference point at 1kHz, which enabled the midrange to open up significantly, possibly because I can play the speaker louder now, not afraid that the bass will overwhelm the room.

I will post more pictures when the final project is complete. Give it a try, but do experiment with various resistor values depending on your room and set up.
 

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See final 'production' version under my system's link, replete with frequency response data across the board.
 
So, my Sequels have only 1 set of binding posts--they cannot be bi-wired. Is there any way I could do this with my speakers? The biggest weakness of the Sequels, I think, is that their bass is sometimes a little on the sloppy side, and has a bit of a hump in the 60-80Hz range...

Would I put a resister in-line with my "+" lead, or just connect both ends to the "+" post, or what?

Thanks,
--Richard
 
The only [probably bad] option one has is to dampen the woofer at the crossover output (put a resistor in series with the + of the woofer), but that changes the impedance of the woofer thus the crossover will behave differently, and I don't think this is worth it.

With a bi-wired situation, the resistors simulate a more resistive cable to the crossover's woofer input, which is a different situation. Basically, I introduced very resistive jumpers from the panel connectors to the woofer. This is the one of two reasons I only buy biwireable speakers, not to actually biwire them (the other is to potentially bi-amp them; not necessary in this case).
 

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