I’ve been playing with an equalizer. I discovered that my speaker system sounded better when I boosted 3dB at the woofers’ operating range. Since my speakers have 2 woofers per cabinet, I realize that one way to achieve 3dB gain at woofers’ operating range is to adding the third woofer to each cabinet. However, I also realize that paralleling 2 woofers together will obtain 6dB gain on woofers’ operating range. So what is the benefit of adding the third woofer to the existing two woofers connected in parallel? Should the 3rd woofer be connected in parallel or series, assume all drivers are identical?
It is possible to create amplifiers that are comfortable with 24 ohms or with 2.7 ohms. Each will be just as efficient.
Since they're commercial speakers, they're either building their own drivers or have the ability to order custom units from their OEM. Assuming you want parallel wiring, a simple solution to that is to produce 16ohm coils for a 5.3ohm nominal with three in parallel, 12ohm coils for a 4ohm nominal (ditto) etc. This is not a particularly difficult task for a manufacturer in design terms; if required they'll simply make other adjustments to the motor & suspension design to suit. Alternatively, they might build nominal 4ohm units for 3x in series; especially for a 3-way with a relatively low filter frequency, the LF impedance is likely to be higher from the box load anyway, which they'll either live with or flatten in the crossover. There are ways of fudging it in a passive filter to get a reasonable load out of 6ohm - 8ohm units in series, assuming you don't want something in the ~16ohm region, but the key there is 'fudge' as it's usually not ideal.
Not particularly; there's nothing innovative about them, it's just a case of companies wanting to pack more into a relatively slim footprint.
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The original design is a conventional 3-way system with two 8-Ohm woofers in parallel. What I was thinking is to adding the third woofer to the system. But, since this is a DIY project, I‘d like to try something challenging. So I wouldn’t go for a 4-way, but a 3.5-way. In my thought, the third woofer will be paralleled to one existing woofer, I’d call it the second woofer, and the impedance there might go lower. Then, these two drivers will be connected in series to a large inductor after the first woofer. It may help the low impedance increases now, unfortunately, not for the deep bass region (about below 100Hz) where I think it could be out of crossover region. That was what I found from the simulations. This’s still be the remaining problem to be solved.
Well one way is to keep the two wired in parallel and insert that third woofer in series with a large inductor, make the third woofer a 4Ohm and the amp sees an 8Ohm load but you would then need to rework the XO and recalculate box sizes so not really worthwhile IMO as a reworking project. Making a second box and adding the .5 woofer as a secondary may work but it may depend on how comfortable you amplifier is with the final load. However if you can find the same woofers but in 4R the result of using the .5 in series may be a reasonable 6R load. All this could be simulated.
Ok, I see. There are two configurations which will produce total impedance presenting to the amplifier at about 5.3 Ohms and they differ in the location of the third woofer.
Which one would you recommend?
Which one would you recommend?