Yes when you roll tubes in Lampi you are keeping Lampi constant. But with amps you will be changing the amp with the tube, and some amps are also more voiced to work with certain tubes, so it makes tube compares there quite different and difficult.
I agree that the sound of the AD1 tube in the LampizatOr may or may not be representative of its sonic qualities as the output tubes on an optimized Single Ended Direct Heated Triode amplifier, such as my custom AD1 SET DHT amplifier:
I will be using my AD1 amplifier as part of a quad amplified high efficiency horn system that I’m putting together:
This system will feature AD1’s, 2A3’s, 46’s and 300B’s or 801A’s SET DHT amplifiers, actively crossovered, directly powering the drivers.
My new custom spherical horns based speakers are in Canada, so it will be a few more weeks before they are delivered.
Once the system is in place, I will be listening to each amplifier, including the 45’s and 801A’s SET DHT amps currently in use in my other systems, to assess each amplifier’s tone, sonic strengths and weaknesses in order to assign an optimal frequency range to each amplifier in my new active quad amped horn system. At that point, I will be able to provide more insightful information with respect to the AD1’s “sound” compared to 45’s, 46’s, 2A3’s, 801A’s and 300B’s.
The obvious thing to remember is the scarcity of vintage AD1 tubes, as not many were produced, when considering an AD1 tube based amplifiers; although Emission Labs (EML) has modern AD1 tubes in new production.