Recently there has been quite a discussion on the TNT forum regarding bass performance. One correspondent asked whether a piano got down as low as 50 Hz and it made me realise that most of us don't really know what frequencies various instruments are capable of.
In my research I also found some interesting stuff on the intensity of sound and what we actually mean when we talk about decibels. Though the following is only a small selection it may help solve all those bar room (and forum) arguments...

Audible frequency range of musical instruments and the human voice.

These for obvious reasons are acoustic instruments and unamplified. The frequency refers to fundamental tones only. To give an extreme example a massive church bell such as 'Big Ben' will produce low frequencies you can feel in your gut and yet the harmonics will go way beyond the range of human hearing.

Instrument	Frequency range Hz
Piano (concert)	27.50 - 4,186.00
Bass Tuba	43.65 - 349.23
Double Bass	41.20 - 246.94
Cello	65.41 - 987.77
Viola	130.81 -1,174.00
Violin	196.00 - 3,136.00
Clarinet	164.81 - 1,567.00
Flute	261.63 - 3,349.30
French horn	110.00 - 880.00
Trombone	82.41 - 493.88
Trumpet	164.81 - 987.77
Guitar	82.41 - 880.00

Human voice

Type of voice	Frequency range Hz
Bass	87.31 - 349.23
Baritone	98.00 - 392.00
Tenor	130 - 493.88
Contralto	130.81 - 698.46
Soprano	246.94 - 1,174.70

Interesting that a sound system will produce almost all the musical fundamentals of an orchestra without bothering the tweeter... thank Heaven for harmonics!

Sound pressure levels

Sound level (dB) approximate observed equivalent.

0. Sound proof room, threshold of hearing.

10. Rustle of leaves in a breeze.

20. Whisper

30. Quiet conversation

40. Conversation at home

50. Typical outside conversation

60. Noise in a large shop (no musac ;-))

70. City street

80. Noisy office with typing (you need to raise your voice)

90. Underground railway train passing

100. Pneumatic Drill at 3 m

110. Prop aircraft taking off

120. Jet aircraft taking off - threshold of pain.

Remember that anything over 80 dB can damage hearing over time.

Audible intensity of musical instruments

Instrument	Range measured in dB
Bass drum	35 - 115
Cymbal	40 - 110
Organ (orchestral)	35 - 110
Piano	60 - 100
Trumpet	55 - 95
Violin	42 - 95

Surprises? Well I never thought a violin could produce more sound than a subway train, and the Piano seems surprisingly lacking in dynamics. It's also sobering to realise that few hi-fi systems will show the full dynamics of the first four on the list - but would you want to be in the room if they did?