SUBJECTIVE AND OBJECTIVE ROOM

ACOUSTIC PARAMETERS

Acoustics of Concert Halls and Rooms

Science of Sound, Chapter 23Concert Halls and Opera Houses (Beranek 1966, 2004)Handbook of Acoustics, Chapter 9 (Gade), Chapter 10 (Ando)

WHAT ARE GOOD ACOUSTICS?

Every concert hall and opera house has its own distinct acoustics. Any music lover, of course, feels the effect of a hall’s acoustical design, often without realizing its importance—unless he or she has made a practice of listening to music in many different venues. Consequently, an attempt to determine which acoustical qualities concertgoers prefer usually elicits recollections about the particular concerts that gave a listener the deepest pleasure. For that individual, a number of elements come together to create that pleasure—the composition, the conductor, the orchestra, and the hall must in combination be excellent to produce a memorable listening experience. For the music professional, however, whether a conductor, a performer, or an acoustical engineer, it is vital to distinguish among these ingredients and to understand what each contributes to the totality. L. L. Beranek (2004)

A COMMON LANGUAGE FOR MUSICIANS, ARCHITECTS, ACOUSTICIANS

•Reverberation and fullness of tone•Definition•Resonance•Intimacy•Liveness•Spaciousness•Warmth•Listener envelopment•Loudness•Timbre

•Acoustical glare•Brilliance•Balance•Blend•Ensemble•Immediacy of response (attack)•Texture•Echoes•Dynamic range and background noise level

ACOUSTIC PARAMETERS (Gade, 2007)

Reverberance (RT, EDT)

Clarity (C)

Sound strength (G)

Spaciousness

apparent source width (ASW)

listener envelopment (LEV)

Timbre or tone color (balance between hi, med, low freq)

Ease of ensemble

Early support

Speech inteligibility

CONDITIONS FOR PERFORMERS

It is also important to consider the performers’ conditions

Musicians will be concerned about reverberance and timbre, of course, but also ease of ensemble and early support

Ease of ensemble relates to how well musicians can hear and play together with their colleagues. Related to the amount of early reflection energy on the stage.

Early support (STearly) depends on ratio of early reflection energy to direct sound (one meter from source)

Desirablereverberationtimes for varioussizes and functions

Variations ofreverberation timewith frequency ingood halls

SUGGESTED VALUES FOR OBJECTIVE PARAMETERS (GADE, 2007)

SUBJECTIVE PREFERENCE THEORY

OF Y. ANDO

Orthogonal parameters

•Listening level (LL)•Early reflection time after the direct sound•Reverberation time (Rtsub) after the early reflection•Interaural cross correlation function (IACC)

CALCULATED VALUES OF FOUR ORTHOGONAL FACTORS AT DIFFERENT SEATS IN THE KRISHIMA

INTERNATIONA CONCERT HALL (JAPAN)

listening level (LL) initial time delay

total reflection IACC