M30 & SHL5 output

[tomsmith]

What is the maximum acoustic output(dB) with 2 speakers in-room, of the M30 & SHL5

[A.S.]

The honest answer is 'something over 100dB at 1m' but as I've never measured the maximum sound pressure level (and respect my ears too much) I can't be precise.

Not only that, tere are many factors which must be taken into account to give a meaningful number such as ....

a) how far away is the microphone?
b) are both speakers playing exactly the same (mono) signal?
c) is the signal bandwidth-limited so that, for example, all deep bass and extreme HF are eliminated and do not reach the speakers?
d) are we measuring long-term maxima or just a burst, and in both cases over precisely what time period?
e) is permanent but minor damage permitted to the speakers?

Harbeth - and indeed all predecessor BBC-monitor speakers are designed to be listened to at a moderate level. You can get an idea of what I think is moderate from the Video Vault of a listening test underway.

[tomsmith]

Do they both have the same mid/bass driver & crossover for that driver?

[A.S.]

They have the same driver. They can't have the same crossover because a) the cabinets are of different sizes b) they have different tweeters c) .....