Speaker Matching
Historically, negative feedback in single ended pentode amplifiers was quite common (for example, the Mullard 3-3 design built around EL84). Today negative feedback is less popular with SET amplifiers, with many having no overall feedback loop. Their frequency response, limited by transformer passband, is then modulated by irregularities in loudspeaker impedance. This, and the very low attainable power levels (3 Watts for 2A3 to 20 Watts for 6C33C), requires careful matching of amplifier to speakers; selection is usually limited to high-efficiency loudspeakers with a sensitivity exceeding 90 dB/Watt.
Read more about this topic: Single-ended Triode
Famous quotes containing the word speaker:
“Good as is discourse, silence is better, and shames it. The length of the discourse indicates the distance of thought betwixt the speaker and the hearer. If they were at a perfect understanding in any part, no words would be necessary thereon. If at one in all parts, no words would be suffered.”
—Ralph Waldo Emerson (1803–1882)