The whole discussion in this thread is about regular (but high-eff, high Bl) woofers with nominal impedance of 4 or 8 ohms (or 2 ohms in IPAL woofers), in attempt to exploit high impedance around their resonance frequencies (with a low tuning vented subwoofer box). But the insurmountable problem with this approach is the low impedance (3 - 7 ohms) around the tuning frequency of the vented box, which is right in (or very close to) the working bandwidth of the said subwoofer. So, the lower part of the subwoofer frequency band has too low impedance to have any benefit with this approach.
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Thank you for answering.I woder if we have 600 ohms professional headphones working all the way up to 20 kHz why can't we have 50...100 ohms subwoofer working in a much lower range? A 600
ohms subwoofer would probably behave very well as half of a whole first order filter, but again...I'm dreaming . Some un-simillar questions popped up in my head when realizing that i'd like having a 2 ohms subwoofer driven with a closed loop circuit around an op-amp operating at +-12v driving a power output supplied at the same +-12v because i can get very good distortions profile in simulations when an op-amp controlls the whole freak while doing the frequency tuning with just another op-amp and probably that would be a much easier thing to do, but I'm no expert in this. Currently I'm building a freak of a bridged power amp supplied at just +-12...15v and I'm looking for the best incarnation of a speaker for it.I say freak because it will be able not to drive an insane amount of current, but it theoretically should be able to controll anything about speaker's movement even loaded with 1 ohm .Now you're telling me that the real obstacle is the box itself at such low impedances.I am not going to use digital tuning, but i will rely heavily on the close loop ability of the finest op-amps for that and hopefully I'll get the best out of it.
ohms subwoofer would probably behave very well as half of a whole first order filter, but again...I'm dreaming . Some un-simillar questions popped up in my head when realizing that i'd like having a 2 ohms subwoofer driven with a closed loop circuit around an op-amp operating at +-12v driving a power output supplied at the same +-12v because i can get very good distortions profile in simulations when an op-amp controlls the whole freak while doing the frequency tuning with just another op-amp and probably that would be a much easier thing to do, but I'm no expert in this. Currently I'm building a freak of a bridged power amp supplied at just +-12...15v and I'm looking for the best incarnation of a speaker for it.I say freak because it will be able not to drive an insane amount of current, but it theoretically should be able to controll anything about speaker's movement even loaded with 1 ohm .Now you're telling me that the real obstacle is the box itself at such low impedances.I am not going to use digital tuning, but i will rely heavily on the close loop ability of the finest op-amps for that and hopefully I'll get the best out of it.