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-   -   Orchestral sound levels at home (https://www.audiobanter.co.uk/uk-rec-audio-general-audio/2169-orchestral-sound-levels-home.html)

John Phillips August 26th 04 07:07 AM

Orchestral sound levels at home
 
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.

--
John Phillips

Neil Jones August 26th 04 08:14 AM

Orchestral sound levels at home
 
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).


http://www.yeodoug.com/resources/faq...iselevels.html (Near the
end)

As you say, these are measured in the orchestra rather than from the
audience, but since you are using theoretical extrapolations for 2)
rather than measurement, why not do the same with the figures for the
violin, for example?

HTH

Neil



John Phillips August 26th 04 08:24 PM

Orchestral sound levels at home
 
In article , Neil Jones wrote:
http://www.yeodoug.com/resources/faq...iselevels.html (Near the
end)

As you say, these are measured in the orchestra rather than from the
audience, but since you are using theoretical extrapolations for 2)
rather than measurement, why not do the same with the figures for the
violin, for example?


Many thanks - some useful figures which are very helpful. However,
as with other measurements taken within the orchestra itself, I know
of no way to extrapolate near field, essentially single-instrument
SPL figures to a SPL for the entire orchestra in the far field region
(i.e. within the audience).

--
John Phillips

ruffrecords August 26th 04 10:09 PM

Orchestral sound levels at home
 
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

Eiron August 26th 04 10:11 PM

Orchestral sound levels at home
 
ruffrecords wrote:


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.


Domestic speakers are about 1% efficient.
That might help.

ruffrecords August 26th 04 11:25 PM

Orchestral sound levels at home
 
Eiron wrote:
ruffrecords wrote:


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.



Domestic speakers are about 1% efficient.
That might help.


What you really need to know is the watts/sq metre. Assuming the
inverse square law applies then 70W acoustic heard at 10 metres is
equivalent to 70/(10*10) = 0.7W acoustic at 1metre. If your speakers
are 1% efficient then you need to feed them 70W to achieve this.

This math seems to simple. Is it right?

Ian

Triffid August 27th 04 12:11 AM

Orchestral sound levels at home
 
Neil Jones pibbled:
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.


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?).


About right. Hi-Fi Choice used to measure maximum SPL's, and big, efficient
speakers driven hard can reach this. Most top out at 105, and are
struggling very hard by then. Given the distortion, they probably sounded
louder than the big ones.

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).


http://www.yeodoug.com/resources/faq...iselevels.html (Near the
end)


Bloody hell. 128dB in front of the bassoon! Am I wrong, or would your ears
go into 'self-protect' mode at this level, possibly hugely affecting the
performance of the musician?

As you say, these are measured in the orchestra rather than from the
audience, but since you are using theoretical extrapolations for 2)
rather than measurement, why not do the same with the figures for the
violin, for example?


Found this: http://www.lhh.org/noise/decibel.htm
although as it's a 'pressure' group (sic) the levels may be distorted! :)

Regardless, my stereo isn't going to go there. Shame, I thought it did.
Perhaps a subwoofer would help.

--
Despite appearances, it is still legal to put sugar on cornflakes.
Strawberries are purely optional.



news@11:00 August 27th 04 04:37 AM

Orchestral sound levels at home
 

"John Phillips" wrote in message
...
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.


snippity snip


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.


Old issues of The Absolute Sound (back when it was digest sized)
occassionally carried mention of Harry Pearson taking his sound meter into
places like Carnegie Hall and noting that orchestras rarely played that loud
in purely empirical terms, seldom exceeding 90dBA in the hall, but to
achieve the same effect in the home required another 20 dB in level which is
LOUD.



John Phillips August 27th 04 05:26 AM

Orchestral sound levels at home
 
In article , ruffrecords wrote:
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.


Yes, that sum is trivial. 70 Watts accoustic power at 10 metres over
a 1/4 sphere (assuming reflection from floor and back of the hall) is
about 113.5 dBA. The trouble is that figure of 70 Watts is very high
compared to the 7 to 10 Watts (i.e. 103 to 105 dBA at 10 metres) that
is quoted elsewhere for a large orchestra. I can find no reference to
orchestral power output that is looks verifiable.

--
John Phillips

John Phillips August 27th 04 05:49 AM

Orchestral sound levels at home
 
In article , news@11:00 wrote:

"John Phillips" wrote in message
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.


Old issues of The Absolute Sound (back when it was digest sized)
occassionally carried mention of Harry Pearson taking his sound meter into
places like Carnegie Hall and noting that orchestras rarely played that loud
in purely empirical terms, seldom exceeding 90dBA in the hall, but to
achieve the same effect in the home required another 20 dB in level which is
LOUD.


I now have a reference to an amateur measurement in a hall at 12 metres
from the orchestra where the SPL did not exceed 85 dBA during a Mozart
symphony (http://www.quiet.org/noiseletter/spring2003/page5.htm).

That seems to be perfectly consistent with Harry Pearson's mesasurement. I
guess his comment about the same effect in the home was meant to be
subjective rather than objective?

--
John Phillips

John Phillips August 27th 04 05:56 AM

Orchestral sound levels at home
 
In article , Triffid wrote:
Neil Jones pibbled:
http://www.yeodoug.com/resources/faq...iselevels.html (Near the
end)


Bloody hell. 128dB in front of the bassoon! Am I wrong, or would your ears
go into 'self-protect' mode at this level, possibly hugely affecting the
performance of the musician?


Threshold of pain is said to be 130 dB on that scale. The conclusion
of http://www.symphony.dk/sektion2/audiograms.htm is a qualified:

"Based on the measured audiograms it may be concluded that musicians
can not expect to achieve pronounced hearing losses from playing in an
symphony orchestra. ..."

--
John Phillips

Stewart Pinkerton August 27th 04 06:10 AM

Orchestral sound levels at home
 
On Thu, 26 Aug 2004 23:09:51 +0100, ruffrecords
wrote:

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've seen 'front stalls' figures quoted between 105dB for an 'average'
symphony orchestra up to 118dB for very large ensembles performing
massive works by Mahler and Wagner.

It's also the case that several 'high end' speaker systems are quite
capable of hitting 120dB peaks in domestic listening rooms, combining
500 watt power handling with 92-94dB/w/m sensitivity. Horns such as
the Avantgarde series with over 100dB/w/m can of course hit similar
levels with ease.
--

Stewart Pinkerton | Music is Art - Audio is Engineering

Stewart Pinkerton August 27th 04 06:14 AM

Orchestral sound levels at home
 
On Thu, 26 Aug 2004 23:11:09 +0100, Eiron wrote:

ruffrecords wrote:

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.


Domestic speakers are about 1% efficient.


That would be about 89dB/w/m, but bear in mind that some designs such
as the Avantgarde Trio horn can achieve 103dB/w/m - and horns don't
obey the inverse square law!
--

Stewart Pinkerton | Music is Art - Audio is Engineering

John Phillips August 27th 04 07:27 AM

Orchestral sound levels at home
 
In article , Stewart
Pinkerton wrote:
I've seen 'front stalls' figures quoted between 105dB for an 'average'
symphony orchestra up to 118dB for very large ensembles performing
massive works by Mahler and Wagner.


Given the lack of precision in most of the sources I have seen, I think
those figures are within the band of consistent peak orchestral levels
for front-row seats (e.g. not the Royal Albert Hall's stalls - maybe
the arena, though).

I think I conclude that for peak levels, normal but good domestic kit
probably does not quite have the ability go to full concert orchestral
levels unless you are accustomed to sitting some metres away from the
front row and/or attending the "average" symphony performance.

It's also the case that several 'high end' speaker systems are quite
capable of hitting 120dB peaks in domestic listening rooms, combining
500 watt power handling with 92-94dB/w/m sensitivity. Horns such as
the Avantgarde series with over 100dB/w/m can of course hit similar
levels with ease.


However the higher-end kit probably does have the ability to create
front-row peak SPLs for all reasonable orchestral music (annoyed
neighbours notwithstanding).

--
John Phillips

Neil Jones August 27th 04 08:36 AM

Orchestral sound levels at home
 
John Phillips wrote:
In article , Neil Jones wrote:
http://www.yeodoug.com/resources/faq...iselevels.html (Near
the end)

As you say, these are measured in the orchestra rather than from the
audience, but since you are using theoretical extrapolations for 2)
rather than measurement, why not do the same with the figures for the
violin, for example?


Many thanks - some useful figures which are very helpful. However,
as with other measurements taken within the orchestra itself, I know
of no way to extrapolate near field, essentially single-instrument
SPL figures to a SPL for the entire orchestra in the far field region
(i.e. within the audience).


I wonder to what extent the measurements results from the individual (ie
the near-field) vs the sound from the rest of the orchestra.




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