Har möjlighet att köpa ett par i bra skick en tusing. Det kanske man skulle testa på.
De mättes upp:
The averaged room response of the AR M4 speakers was among the flattest we have ever measured. ±1.5 dB from 200 to 20,000 Hz. We measured the responses of the two 6-inch drivers with close microphone spacing. The upper one (bass/midrange) had a well-damped resonance and a response variation of ± 1 dB from 65 to 400 Hz. Its output dropped at 12 dB per octave below 65 Hz. The lower driver (bass) had a higher-Q resonance, peaking at 70 Hz and falling off at 6 dB per octave at higher frequencies and 12 dB per octave below 70 Hz.
The sensitivity of the M4 was 89 dB SPL, slightly better than rated. Its distortion with a 3.2-volt drive level (corresponding to a 90-dB SPL in our sensitivity measurement) was less than 1 percent from 75 to 700 Hz, rising to 3.8 percent at 50 Hz and a maximum of 7 percent at 30 Hz.
http://www.hifi-classic.net/review/acou ... m4-61.html