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Note that the high-highish output impedance of the SE amp woo interact with the (poor) ipedance curve of the loudspeaker. I expect a bump in FR at just beow 2kHz, and some irregularities at the low frequency were the imoedance shows the foreshortening of the horn length,
dave
Well noted, very wild impedance and phase set, proprably also with reactance and inductance, hence the importance of use direct from the amp no-crossover speakers.
The Decware Rachel EL34 SET and the Wright Royale $1485 both specs around 6/7W, having the Royale much bigger OPTs than the shy underside Rachel transformers, both amps can be able to drive this Klipsch and still are simpler SET amps than the Tori.
However there is various ways to decrease the noise floor in an tube amp, as bring the circuit closer to the metal table/plate of the amp, use low noise tubes or even use a volume pot and others.