I bought my Frazier Super Monte Carlos in 1977 & they are still in use in one of my systems.
I bought my Dahlquist M-905's in the late 1980's (which tested to these results):
The close-miked woofer (and port) response was also considerably flatter than we have measured from most speakers, with a very small bass-resonance peak. At the system resonance of 60 Hz, the output was only about 2 dB above its average level in the upper part of the woofer’s range, and even that minor output variation was spread over almost two octaves. When the bass curve was spliced to the room-response measurement, the resulting composite frequency response was flat within about ±2 dB from 26 to 20,000 Hz. The horizontal directivity of the tweeter was only discernible in the room measurement above 10,000 Hz.
We measured the sensitivity of the M-905 as 87 dB SPL, which was lower than the rated 91 dB but still about average for speakers of its size. The difference may have been a result of different test conditions since we used a full-range pink-noise signal while Dahlquist’s rating was made at 1,000 Hz. The system’s minimum impedance was about 4.8 ohms in the 8,000- to 10,000-Hz region, and it measured 7 ohms at 150 to 200 Hz. Its maximum impedance was 28 ohms at 60 Hz, and there was a broad peak of 18 ohms in the vicinity of 1,500 Hz.
We measured the woofer’s distortion with a 4-volt drive level, corresponding to a 90-dB SPL at 1 meter. The distortion was less than 1 percent from 100 Hz down to almost 60 Hz, the effective crossover to the port. Below that crossover the distortion rose to 5 percent at 45 Hz and 9 percent at 35 Hz. In high-power tests with single-cycle tone bursts, the woofer began to sound “hard” at about 350 watts into its 8.5-ohm impedance at 100 Hz. At higher frequencies the amplifier clipped—at outputs of 490 watts at 1.000 Hz and 1,380 watts at 10,000 Hz—before distortion became visible on the acoustic waveform.
Quasi-anechoic FFT measurements showed an overall group-delay variation of about 0.1 millisecond between 4,000 and 20,000 Hz and 0.5 ms between 1,000 and 20.000 Hz, convincing evidence of the attention paid to the phase characteristics of the M-905.
I have never felt the NEED for anything newer, although I have added some custom made passive sub's (by me) to give a bit more up to 80 Hz (to both the Frazier's & the DQ M-905's.
I am finally intrigued by something else: the KEF LS60.
Mainly because I have moved into a home that is less than 1/2 the size of where I was at.
I'll be in some place larger again, in a few years.
& maybe I won't change but maybe I will.
