I recently upgraded my fronts from some JBL N28s to Athena ASF2s and the 250hz crossover that the Optimus SW12 comes with just isn't working for me. Athena suggests 50 hz on their own subs with the ASF2s. I have an Adcom amp for my fronts so the sw12, which is passive, is running solo off of my receivers speaker wire outs. What options do I have for reducing the sub frequencies? I would rather not alter the sub directly so an outside in-line solution would work the best for me. I am willing to spend up to $100 on this.
Unless your prepared to do some trial and error...
your biggest hurdle is going to be quality. It's difficult to buy or build a passive x-over to match the characteristics of the driver unless some engineering spec's are known. It's a shot in the dark! You can try a prefab passive from an autosound dealer, or Parts Express has some that go down to 80Hz or so but again, you may not get optimum performance out of the sub. Another thought would be to invest in a plate or remote amp that has a built-in adjustable x-over but for $100, you will still have a quality issue. The amp doesn't have to be mounted on the sub, just a box about a foot square and 4"deep will do. Personally, I would do a dedicated amp for the sub as your mains and the sub will probably sound much better at elevated sound levels. With a dedicated amp, you can use a plug-in module inline between the Adcom pre-out and the sub amp in for about $25-$30 if the amp doesn't have an onboard x-over.
If I think of anything else, I'll let you know.
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