When picking out an amplifier, there are a couple of things to consider other than the sound, which is, of course, a given. Equally important are the amp's reliability and the power it produces – can it drive your speakers? Seasoned tube aficionados already know that fifteen solid watts from a well-designed tube amp is quite a bit of power.
They also know that when challenged, a tube amp can behave better than a solid state amp. When pushed to its limits, the tube can amp “lose its composure” in a much more sonically-pleasing way than a solid state amp, which can sound raspy and coarse. Tube amps will "compress", which is a character that some of the best guitar players and recording engineers in the world understand and actually seek.
So, now that you’ve settled on tubes and are comparing brands, consider this: if two amps are running in ultra-linear mode, and both are using a pair of KT88 tubes per channel, how can one be rated at 40 watts per channel, the other at 80 watts per channel? This is a simple engineering and math question, and these are the two possible answers:
The higher powered amp isn't really meeting it's specified power rating and/or the tubes are being run very hard to get that extra power. Both scenarios are very common.
The benefit of doubling power from 40 watts to 80 watts will only increase maximum volume levels by approximately 3dB. Not much. A one decibel increase is the smallest volume increase that is detectable by the human ear. In other words, the up-side is negligible and the down-side is significant: tubes wear out more frequently, increasing operational costs. Even worse, catastrophic failures may result due to running the tube's plate and screen voltages up to their jagged edge.
PrimaLuna engineers understand all of this, and have created components that have reference quality performance, all the power you will ever need, and are eminently reliable. Tubes are running at voltages far below their maximum threshold and all PrimaLuna amps have a variety of safeguards creating a more dependable product and a more satisfying ownership experience.