I suspect that the internal environment of the T1500 is less crowed with fewer parts as SET is simpler. Higher power push pull amplifier will have a higher parts count.
Charles
Charles
Cube Audio Nenuphar Single Driver Speaker (10 inch) TQWT Enclosure
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Parameters (from Cube Audio):
Power: 40 W
Efficiency: 92 dB
Frequency response: 30Hz - 18kHz ( 6db)*
Dimensions: 30 x 50 x 105 cm
Weight: 40 Kg