I have M60 v2's, QS8's, VP150 for my HT setup, and upstairs I'm using M2's and M3's.

I'm trying to figure out how sensitive they are. I look at the technical specs and there are two numbers - 93db and 89db - which is it?

I've seen people mention that Axiom's have a sensitivity of 93db, but in a review I just read it said they are 89db. Which number do *I* care about?

The reason I am wondering is more that just curiosity, since I ordered a Harman Kardon 7550HD and have been reading the manual in preparation for it arriving. In the manual it talks about setting your speaker sensitivities in relation to 88db or something like that. I came here and was hoping to just find the number(s) I needed in the tech specs but I'm just confused.

The anechoic measurement is done in an anechoic chambre, or sound room, the other measurement is "in room" which will be closer to what you would get in your own home environment. Have a look on Axiom's site, you'll find some articles about their anechoic chambre as well as some pictures of it. It is a replica of the NRC's anechoic chambre in Ottawa.

E, you want to use the "In-Room" spec.

I am not sure I understand why you are worrying about it. The amp doesn't really care about the sensitivity and you adjust each speakers output via the speaker setting in the amp to match the other speakers. The speaker sensitivity has no bearing on its output so far as the ability to set them to reference volume in the amp.

The sensitivity rating is to give you an idea on how much power they require to achieve a certain volume level, the more sensitive the speaker the less power required to achieve louder volumes.

It's probably how the HK sets the speaker trims without an auto-setup, or use of an SPL meter. Just tells the user to find the sensitivity rating for each, and adjust the setting in the receiver relative to 88 dB.

ET, when speaker sensitivity is mentioned, the number is almost always the lower anechoic(direct sound, no reflections)figure, unless specifically stated otherwise. The Axiom measurement in a particular room setting added 4dB to the anechoic number, indicating that the contribution from room reflections at that point was slightly greater than the direct sound(if both were equal, the increase would be 3dB).

Yeah I know what it means. I'm just curious how sensitive the speakers are so I came here to find out.

I guess I'll use the lower, anechoic number.

I guess the real question is whether the Harmon Kardon guide referred to in-room or anechoic sensitivity. Might be worth checking the specs for some HK speakers to see whether they spec sensitivity in-room or in an anechoic environment.

A few dB isn't really going to matter either way, of course - I think the HK manual is really saying "when you set your speaker levels, use a volume setting that isn't really loud or really quiet".