I went ahead and contacted a few companies late last night asking for detailed information on their sensitivity ratings:
Ascend Acoustics: ”...our sensitivity measurement is anechoic, with a microphone distance of 1 meter and an input voltage of 2.83v. We use the averaged amplitude over the range of 300Hz - 3kHz. These are the current but not-so-widely-accepted standards.” -D. Fabrikant
KEF: “Generally most companies take their sensitivity rating at 1kHz – 1 meter – 2.83 volts (1 watt). Weighting doesn’t matter as it’s a constant frequency/power relationship. In room sensitivity is really not a thing as sensitivity has nothing to do with in-room acoustics but is really just how a speaker reacts to the power applied to it. Our sensitivity ratings are always somewhat conservative, meaning what we publish is typically a little lower than the actual rating – not by a lot but a dB or so maybe.” -Troy, KEF service
NHT: “We use the average anechoic SPL over a range (~500-2KHz) @ 1M, on-axis with 2.83 VRMS driving voltage.” - G. Chang
Sony: “We would like to inform you that we do not have the information that you seek.” They suggested live chat, I did that and the employee said they don’t have the test data and they don’t generally share info on the developmental process.
ATC: “We measure the loudspeaker on axis in essentially an anechoic environment. We apply no weighting to the response. We then take the average level through the linear region and quote this figure.” - R. Newman
PMC: I got B. Esry, he asked what speakers I was asking about and what amp I have, I picked a model (Gold DB1) and told him what amp I have, and he said it was enough to power them, and that dealers even use AVRs sometimes.
MartinLogan: “For floor standing ESL speakers:
These are measured from approximately 3.2 meters back, with the speaker placed in a parking lot, and with the speaker toed in per the instructions. The microphone is placed at the same position as an optimum listeners ear would be placed. We then compensate the SPL measurement by the distance to calculate an equivalent 2.83V @ 1 meter reading. The Average SPL is calculated by averaging the measured SPL over the speakers rated frequency response window.
For non ESL speakers:
Very similar process and setup to the above, but these are measured in room, (a typical sized listening room, not an anechoic chamber) at around 2 meters back. We then perform similar compensations and calculations to get to the standardized 2.83V @ 1m specification.”
- M. Lohmeyer
GoldenEar: “Our measurements are Anechoic.”, but didn’t know the frequency range used. -Chris
Focal: “My technical contact in France is away until the end of July, but I seem to remember it was A-weighed in anechoic...I'm pretty sure it is done at 1 kHz...I can safely say that most models are fairly efficient and easy to drive.They do not require a lot of watts, but respond better to high current, high quality electronics. For instance, you would often get better results from a high quality, hand made 75w European or American product, than you would from a 150w Japanese product.” - Michel
Q Acoustics: “Our measurements are carried out on axis in a anechoic chamber @ 1m , 1 kHz, 2.83 V rms”
Sonus Faber: “...sensitivity ratings measurements are obtained as follows: In our semi-anechoic room (coherent and certified since 100Hz), Not weighted, Average 100-20.000Hz, 1watt @ 1mt, On-axis between mid and tweeter” -Stephano
Klipsch: Waiting on response
Pioneer: Waiting on response
Polk: Waiting on response
Micca: Waiting on response
Dynaudio: Waiting on response
ELAC: Waiting on response
HTD: Waiting on response
Revel/Harman: Waiting on response
DefTech: Waiting on response
Any others?
I tried B&W but they have no email nor chat, they give you the phone number of your closest dealer.
I was surprised at how fast NHT & Ascend replied, they replied before I even woke up. They are working at ungodly hours!