Elliot,
Your Qs followed by replies.
For SS amps, power/voltage is halved for each doubling of impedance, a potential negative for amps with borderline power. For tubes including OTL it’s all upside (at least up to 16 ohm); in some cases like Ralph’s lovely S30 OTL, power increases 50% (45W, +1.5 dB) @ 16 ohm vs. 30W @ 8 ohm. Interestingly, compared to S30 > 8 ohm, 16 ohm has more powerful bass and IIRC even lower bass cutoff! IIRC, with Ralph’s larger amps the 16 ohm power advantage is less than with S30.
Lower speaker cable resistance can have similar effect as increased speaker load impedance; the caveat is that cable inductance rises with conductor thickness, so as usual it’s not a free lunch upgrade,
Your Qs followed by replies.
1. why/how do 16 ohm speakers make amps sound better, with more resolution?For an estimated 99+% of amps the higher the load impedance the greater is the amp’s current capacity and the more pleasant and agreeable is distortion spectra. A 16 ohm speaker draws half the current of a 8 ohm speaker.
For SS amps, power/voltage is halved for each doubling of impedance, a potential negative for amps with borderline power. For tubes including OTL it’s all upside (at least up to 16 ohm); in some cases like Ralph’s lovely S30 OTL, power increases 50% (45W, +1.5 dB) @ 16 ohm vs. 30W @ 8 ohm. Interestingly, compared to S30 > 8 ohm, 16 ohm has more powerful bass and IIRC even lower bass cutoff! IIRC, with Ralph’s larger amps the 16 ohm power advantage is less than with S30.
2. why speaker cables less critical?The sum total amplifier load = speaker impedance + speaker wire series resistance. The higher is speaker impedance the less (as a ratio of 100%) does the speaker wire contribute to the load. You hear less cable and more speaker because the latter contributes a higher ratio of the total load.
Lower speaker cable resistance can have similar effect as increased speaker load impedance; the caveat is that cable inductance rises with conductor thickness, so as usual it’s not a free lunch upgrade,