# 4x8 Stereo/Mono Cab Build with Tweeter Defeat??



## studiodog (Sep 10, 2010)

Hi folks,

I'm part way into a 4x8 stereo/mono cab build (3/4" solid pine box with Baltic birch baffle and back, currently using cheap-ass Pyramid 8" woofers (I already own them) but looking at future upgrades as cash and Significant Other allow). 

I play both acoustic and electric instruments, so my plan is to wire in piezo tweeters to get the full range coverage for the acoustic applications, with a tweeter defeat switch so I can run electrics without the added high end. Each side (Left/right) will then be a WTW configuration wired in parallel, 4 Ohms per side in stereo, 8 Ohms mono (using a series adapter cable). 

I may be over-thinking the build a bit here, but I'm waffling on the defeat switch - should I use a SPST or DPST switch on each tweeter? Does it matter? SPST would interrupt the positive conductor to the tweeter (like a standard household light switch) while a DPST would interrupt both positive and negative leads to the tweeter. If I use an SPST, would leaving the negative conductor connected affect the way the amp sees the piezo? 

I've tried googling for wiring schematics but so far have come up dry on that effort. If anyone can steer me in the right direction it would be most appreciated.


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## washburned (Oct 13, 2006)

spst would do. as long as the circuit is incomplete, nothing will flow. just make sure the tweeter is in parallell with everything else.


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## studiodog (Sep 10, 2010)

washburned said:


> spst would do. as long as the circuit is incomplete, nothing will flow. just make sure the tweeter is in parallell with everything else.


Thanks, washburned! I had a feeling an SPST was all that was required, but thought I'd make sure. And yes the tweeters will be wired in parallel with the woofers. 

I'm quite keen to get this project finished, as a full-range stereo cab will essentially provide a compact PA speaker system for small gigs. This one, with the current speakers, will be capable of 400W total output in either stereo or mono, so it will be more than sufficient for the solo gigs I play. I'm also drooling at the lush stereo chorus potential! kkjuw


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