300B SET Amp driving Wilson Sabrinas

Makes me think not all SET amps are created equally…or all watts for that matter.

@mootsdude They aren't! It makes a big difference how the power tube is loaded. Some try to get more power, but really if you want the amp to handle more difficult loads, its better to sacrifice a bit of power so that when the speaker impedance dips down, there is in fact a bit of current available.

But Watts are Watts and a sound level pressure meter always shows wut up in that regard. When it sounds loud but the meter is saying its not all that loud, that tells you distortion is making it seem loud.

@mootsdude If you used that amp with a speaker of 10dB greater sensitivity, you'd find that amp more spacious and more detailed, also smoother sounding all for the same reason: its making less distortion.

The Coincident, being designed to be easy to drive, points you in that direction.

OTOH, you might also be surprised how well a lower power PP amp would do on your Snells. Decades ago Dynaco used to make a small power amp called the ST35 which made 17 Watt/channel using a pair of EL84s per channel. If one of those is refurbished properly it gives you pause when compared to a good SET.

The surprise, not only did the Elekit drive the Sabrinas very well (improved clarity and tonality), but at the same volume with the same input level as the Modwright! Using a passive preamp, when I set the volume knob on the preamp to the same point for both the Modwright and the Elekit it results in essentially the same volume from the speakers.

@gareents There is more to this than just power. The reason the SET seems to keep up with the more powerful Modwright is due to the distortion it makes. As you push it harder, higher ordered harmonics show up (the amp lacks feedback so this is normal) which convince your ear that the sound is louder than it really is. A sound level pressure meter (which is available as an app for most phones) will reveal the truth of the matter.

Put another way, the mark of a good system is that it doesn't sound loud, even when it is. This is because it makes less of the artifacts that the ear uses to sense sound pressure, so sounds more relaxed.