What does Q mean in speaker specifications?

This is all great information. You learn something new everyday. @yogiboy are you planning to order the Q7s?

For anyone interested in actually listening to the new Falcon Acoustic Q7

it will be one of 17 models on exhibition at SpeakerFest 2022 August 27th

in Fountain Hills AZ. See the azavclub website for more details!

@mrteeves

I am on the fence on buying them. I would love to give them a try. I’ve owned many LS3/5A type speakers including the Harbeth P3ESR that I prefer over the other ones that I have owned!

BTW, those Falcons ( kit ) look like a real bargain. I have also owned the Falcon IMF-100 transmission line and they was real nice! I sold them to my nephew and he loves them!

I like the answers here. Very good. I'd like to add that in my DIY towers people are often amazed that I get so much bass from what appears to be 10-inch drivers, then I pull the grills off exposing only 8-inch drivers. This effect that everyone is talking about is simply utilizing the resonate freq of the enclosure to lift to the bottom end. If done well, you will not notice the rise but just experience a steady bass volume as the Frequency gets lower. And as one person mentioned what he called 'Stored' energy in the cabinet. Though this is a component it is ONLY a component. 

To be a little clear:

Qtc is a driver parameter.  You read it when shopping for a driver.

Total system Q is how a driver performs in a specific cabinet.  You adjust this when using a cabinet simulator.