In my humble opinion, a little old speaker manufacturer in my hometown of Kingsport, Tennessee, has a very nice speaker out now. The Watkins Stereo Generation 4 is quite amazing. William "Bill" Watkins, Sr., and Bill, Jr. have built a solid reputation over the last 46 years. Bill, Sr. developed and patented a Dual Voice Coil Woofer that was used by Infinity. Below is a description I found from a review:
"The 8 ohm coil is the primary VC, but at resonance (woofer+cabinet) the very complex crossover shifts the signal to the second voice coil. In effect the 2nd coil operates in a narrow band The effect is to level the speaker impedance (at resonance, impedance and efficiency are at max, and cancel out) but more significantly, the phase of voltage and current remain stable (at resonance they are at 90 degrees, a tough amp load). Watkins woofers also maintain a deeper bass, because the second VC band pass was at the low end of the speaker's response. A typical 12" in a big box might resonate at 42Hz. A Watkins could move this down to 28Hz."
Last I saw, the price was $2,500 a pair straight from Watkins Stereo shop which has been at the same location on Center Street in Kingsport since opening 46 years ago. I used to stop in there all the time as a teenager in the mid and late '70's. They currently sell their speakers, VPI and Oracle Turntables, Ortofon 2M and Cadenza cartridges, and Yamaha Amps. I hope this helps, and the specs are on the web page.
https://www.watkinsstereo.com/
"The 8 ohm coil is the primary VC, but at resonance (woofer+cabinet) the very complex crossover shifts the signal to the second voice coil. In effect the 2nd coil operates in a narrow band The effect is to level the speaker impedance (at resonance, impedance and efficiency are at max, and cancel out) but more significantly, the phase of voltage and current remain stable (at resonance they are at 90 degrees, a tough amp load). Watkins woofers also maintain a deeper bass, because the second VC band pass was at the low end of the speaker's response. A typical 12" in a big box might resonate at 42Hz. A Watkins could move this down to 28Hz."
Last I saw, the price was $2,500 a pair straight from Watkins Stereo shop which has been at the same location on Center Street in Kingsport since opening 46 years ago. I used to stop in there all the time as a teenager in the mid and late '70's. They currently sell their speakers, VPI and Oracle Turntables, Ortofon 2M and Cadenza cartridges, and Yamaha Amps. I hope this helps, and the specs are on the web page.
https://www.watkinsstereo.com/