“Can I plug my 16 ohm speaker into my Quilter”?
Yes! Quilter amps are fully protected and can drive any load, or no load at all. Tone and Master Volume settings will vary somewhat, but it will play fine.
For best results use the jack that is closest to matching your speaker impedance: 4-ohm outlet for 2-4 ohm loads, and the 8-ohm outlet for 8-16 ohm speakers. When connecting two speakers, the upper jack is engaged and reduces the amplifier impedance to support the additional load.
16 ohm speakers will draw more power than 8-ohm speakers due to the amp’s high voltage swing. For best results, set the Master to about half the rated power, or about 30% less rotation, than you would use with an 8-ohm load. When operating with no speaker, it is wise to keep Master below about 50% to avoid premature clipping of the Class-D amplifier block, which could affect tone in the Direct Out.
Connect a single 8 through 16-ohm speaker to the lower jack.
Connect a single 2 through 4-ohm speaker to the upper jack. It is not necessary to plug anything into the lower jack.
For two 8-ohm speakers, or any other mix of impedances, plug one into each jack. Power will divide between the two speakers. The amplifier will not be bothered by impedance mismatches, so if the tone sounds OK, go for it.