John Phillips wrote:
To pursue an academic thought (rather than a desire to annoy the
neighbours) I was thinking about whether "orchestral" sound pressure
levels can be reasonably achieved at home.

I think the answer is yes, from just personal listening experience in
the concert hall (classical orchestral music, not normally closer to the
stage than 10 metres) and listening at home. However the more academic
answer depends on at least two factors:

1. What peak SLPs are achieved in a reasonably good seat in a concert
hall where an orchestra is playing, say 10 metres from the front
centre of the orchestra?

2. What reasonable (relatively undistorted) peak SPLs will normal but
good quality home audio kit produce?

The answer to 2 looks fairly simple. Peak SPLs about 109 dBA seem
theoretically achieveable at 1 metre from an average sensitivity
loudspeaker (about 89 dBA for a nominal eight-ohm Watt, I think) driven by
a 100 W amplifier (+20 dBW). I think also that a reasonably good modern
loudspeaker could, in practice, go up to to 109 dBA on occasional peaks
(is this correct?).

Compensating for (i) being, say, 3 metres away from the speakers, but in
a non-anechoic space, and (ii) having two loudspeakers, I think that 109
dBA probably comes down to 103 to 106 dBA peak SPL at the listening chair
(still VERY LOUD, nevertheless).

However, the answer to 1 ("orchestral SPLs?") has eluded a quick Google
search. Yes, lots of SPL figures can be found for an orchestra but they
vary widely and so far none I have seen is adequately qualified to answer
the question.

Are there any good references to orchestral SPLs in the auditorium? The
best references I have found are to SPLs in the context of the exposure of
the musicians themselves to high SPLs but I don't think these measurements
are easily translatable to SPLs in the hall.


I have never heard it expressed in SPL but a long time ago I read that
the peak output from an orchestra is about 70 watts of acoustic power.
You should be able to work it out from that.

Ian