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Education

Acoustic Symbols

A-Z list of symbols commonly used within acoustics.

α


αE


A


AG


b


b(θ, ϕ)


B


BL


ℬ


ℬT



cg


cp

C


C‚Ñò


c‚Ñò


Cv


cV


CNEL


d


d’


D


DI


DNL


DT


e


E


Ek


Ep


EL


ℰ


ℰ


f


fr


fufi


F


Fe


g


G


h


H(θ, ϕ)


H(Tk)


I


Iref


I(t)


IIC


IL


ISL


‚Ñê


k


kB


k,km


‚Ñì


L


LA


LC


Ld


Ldn


Le


Leq


Lex


LEPN


Lh


Li


LN


Ln 


LTPN


Lx


LNP


m


mr


M


ℳ


ℳℒ


ℳref


N


NCB


NEF


NL


NR


NSL


p


P


Pe


Pref


PR


Pr


PSL


PTS


q


Q


r


rt


rs


R


Re


·πò


Rm


Rr


RI


RII


RL


ROC


‚Ñõ


s


sL


S


SA, SB


SENEL


SIL


SL


SPL


SS


SSL


STC


Sv


SWR


T


TI


Tk


Tem, Tme


T‚àè


TL


TNI


TS


TSR


TTS


u


U


Ue


V


VL


Vref


w


W


x


X


Xm


Xr


y


Y


z


Z


Zm


Zr


α


β


γ


δ


η


ηB


ηe


θ


Θ


κ


λ


Γ


ξ


Ξ


Π


Πi


ρ


ρ0


ρL


ρS


σ


σS


τ


ϕ


Φ


ω


ω0


ωd


ωu, ωl


Ω


Ωeff


δ(υ)


δnm


1(υ)


acceleration; absorption coefficient (dB per distance); Sabine absorptivity


random-incidence energy absorption coefficient


 sound absorption


array gain


loss per bounce; decay parameter


beam pattern


magnetic field; susceptance


bottom loss


adiabatic bulk modulus


isothermal bulk modulus


speed of sound


group speed


phase speed


electrical capacitance; acoustic compliance; heat capacity


heat capacity at constant pressure


specific heat at constant pressure


heat capacity at constant volume


specific heat at constant volume


community noise equivalent level (dBA)


detection index


detectability index


directivity; dipole strength


directivity index


detected noise level


detection threshold


specific energy


total energy


kinetic energy


potential energy


echo level


time-averaged energy density


instantaneous energy density


instantaneous force; frequency (Hz)


resonance frequency


upper, lower half-power frequencies


peak force amplitude; frequency (kHz)


effective force amplitude


spectral density of a transient function; sound-speed gradient; acceleration of gravity


conductance


specific enthalpy


directional factor


population function


time-averaged acoustic intensity; current, effective current amplitude


reference acoustic intensity


instantaneous acoustic intensity


impact isolation class


intensity level


intensity spectrum level


impulse


wave number


Boltzmann’s constant


coupling coefficients


discontinuity distance


inductance


A-weighted sound level (dBA)


C-weighted sound level (dBC)


daytime average sound level (dBA)


day-night averaged sound level (dBA)


evening average sound level (dBA)


equivalent continuous sound level (dBA)


noise exposure level (dBA)


effective perceived noise level


hourly average sound level (dBA)


intensity level re 10 ‾¹² W/m²


loudness level (phon)


night average sound level (dBA)


tone-corrected perceived noise level


x-percentile-exceeded sound level (dBA, fast)


noise pollution level (dBA)


mass


radiation mass


acoustic inertance; bending moment; molecular weight; acoustic Mach number


microphone sensitivity


microphone sensitivity level


reference microphone sensitivity


loudness (sone)


balanced noise criterion curves


noise exposure forecast


noise level


noise reduction


noise spectrum level


acoustic pressure


peak acoustic pressure amplitude


effective acoustic pressure amplitude


reference effective acoustic pressure amplitude


privacy rating


Prandtl number


pressure spectrum level


permanent threshold shift


charge; source strength density; thermal energy; scaled acoustic pressure (p/p0c²)


quality factor; source strength (amplitude of volume velocity)


specific gas constant; characteristic acoustic impedance; specific acoustic resistance


transition range


skip distance


resistance (acoustic, electrical, mechanical); reflection coefficient; radius of curvature


Reynolds number


range rate


mechanical resistance


radiation resistance


intensity reflection coefficient


power reflection coefficient


reverberation level


receiver operating characteristic


universal gas constant spring constant; condensation


spring constant; condensation


apparent source level


cross-sectional area; surface area; salinity


scattering strengths per unit area


single event noise exposure level Lex (dBA)


speech interference level


source level


sound pressure level


sea state


source spectrum level


sound transmission class


scattering strength per unit volume


standing wave ratio


period of motion; temperature; tension; transmission coefficient; reverberation time


intensity transmission coefficient


temperature in kelvin


transduction coefficients


power transmission coefficient


transmission loss


traffic noise index (dBA)


target strength


target strength for reverberation


temporary threshold shift


particle speed


peak particle velocity amplitude; volume velocity


effective particle velocity amplitude


volume; voltage; effective voltage amplitude; volume displacement


voltage level; voice level (dBA)


reference effective voltage amplitude


angular frequency; bandwidth


explosive yield


specific acoustic reactance


electrical reactance


mechanical reactance


radiation reactance


transverse displacement


admittance; Young’s modulus


specific acoustic impedance


impedance (acoustic, electrical, mechanical)


mechanical impedance


radiation impedance


spatial absorption coefficient


temporal absorption coefficient; one-half the flair constant; a nonlinearity coefficient


ratio of heat capacities; attenuation coefficient; a nonlinearity coefficient


boundary layer thickness; skin depth


coefficient of shear viscosity; efficiency


coefficient of bulk viscosity


effective coefficient of viscosity


incidence angle; phase angle; grazing angle; horizontal beam width; elevation angle


phase angle of impedance


thermal conductivity; radius of gyration; transverse component of the propagation vector


wavelength


c times the eikonal; Goldberg number


longitudinal particle displacement


amplitude of ξ


time-averaged power


instantaneous power


instantaneous density (kg/m³); probability density function


equilibrium density


linear density (kg/m)


surface density (kg/m²)


Poisson’s ratio; standard deviation; extinction cross section


scattering cross section


relaxation time; pulse duration; processing time


transformation factor; phase angle; torsion angle; turns ratio; inverse turns ratio


velocity potential


angular frequency (rad/s)


natural angular frequency


damped angular frequency


upper, lower half-power angular frequencies


solid angle


effective solid angle


Dirac delta function of argument υ


Kronecker delta


Heaviside unit function of argument υ (unit step function)


Service Areas

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Service Map - NOVA Acoustics

Accreditations & Memberships

  • ISO-9001
  •  Institute Of Acoustics
  • Construction Line
  • LABC
  • IEMA
  • HAS

testimonials

- Paul Hastings

★ ★ ★ ★ ★

30th May, 2017

I engaged Nova at the outset of my project (which I recommend you do) to assist with providing a detailed material specification and installation guidance. There was always someone available to help with practical enquiries and advice...

- C.G. Henry

★ ★ ★ ★ ★

29th Nov, 2017

I had Adam come round to a property which i thought was beyond repair. He gave sound advice with exact details of what needed to be carried out in the most cost effective manner. Once the works were carried out he returned, tested it...

- Andrew Youngson

★ ★ ★ ★ ★

6th Dec, 2017

I have worked with the team at nova on a number of projects and have always been very helpful and competitively priced. Highly recommend this company for any sound test and report.

- Carol Chaplin

★ ★ ★ ★ ★

14th Jun, 2017

Excellent service, engineer was very informative and helpful.  Good customer service being able to speak to knowledgeable people on the telephone when making inquires about the procedure involved for the sound testing of our property...

- Bun Bar

★ ★ ★ ★ ★

2nd Dec, 2015

Good efficient service. Recommend it to all.

Bright Construction UK Ltd

- Gavin Boby

★ ★ ★ ★ ★

9th Nov, 2015

Very attentive and friendly service, keen to serve the client, and absolutely not about dragging the case out for fees - will work to save the client fees, and understand the practicalities of the case and the opposition that applications...

- Ejaz Shah

★ ★ ★ ★ ★

9th Nov, 2016

Adam was very attentive and very professional answered all my questions and returned all calls the engineer arrived at the time agreed and again explained everything before carrying out the test , and we received our report within couple...

- Charles OKell

★ ★ ★ ★ ★

23rd Feb, 2017

Its a tricky area and you need the right support, Paul Robinson  brought Adam's team to the table and we'll be working together again in future for sure.

- Ainsley Black

★ ★ ★ ★ ★

14th Dec, 2016

Although we had followed the building reg, in terms of sound insulation the property conversion still failed the sound Test. Adam was very helpful and professional and guided us to the point that when it was retested again we passed. Would...

- Robert Buchanan

★ ★ ★ ★ ★

19th Jun, 2017

Friendly efficient and cost effective service, without complication

- Hepple Property Care Ltd

★ ★ ★ ★ ★

26th Oct, 2017

Very quick service, would recommend to others

- Ian Fairbairn

★ ★ ★ ★ ★

20th Dec, 2016

Excellent service and communication with all the members of staff we had dealings with.  A very professional approach and attitude by all.  An experience that is refreshing within the building sector and a company I could recommend...

- Daniel Cogdon

★ ★ ★ ★ ★

2nd Oct, 2017

Fast turn around and great service, recommended

- Allan Proctor

★ ★ ★ ★ ★

21st Sep, 2016

Excellent service by Adam and the team at Nova. The service they delivered was efficient, competitive and I would highly recommend them!

- Carol Richards

★ ★ ★ ★ ★

20th Jul, 2016

Having selected Nova Accoustics to perform a sound test on my latest project, I found the whole process completely professional, prompt & efficient .

The phone contact to set up the appointment was extremely  helpful...

- Michael Dickinson

★ ★ ★ ★ ★

1st Mar, 2017

Having used Nova Acoustics on several projects, I would not hesitate in recommending this company.

- Steph Openshaw

★ ★ ★ ★ ★

7th Sep, 2017

Fantastic service very quick and punctual highly recommended.

- Chris Bullerwell

★ ★ ★ ★ ★

22nd Nov, 2016

Used Nova Acoustics to sound test a property we'd converted in the Newcastle area.

Excellent service from start to finish. Professional, helpful & reliable throughout...highly recommended.

- Andrew Holmes

★ ★ ★ ★ ★

23rd Mar, 2017

Really helpful team of people and very quick service, which was greatly appreciated.

- Siying Lid

★ ★ ★ ★ ★

17th Aug, 2016

We are a small design firm and NOVA Acoustics provided very sufficient services to our clients with reasonable price. And they are quick to respond too.  Highly recommended.

- Floors By Design Leicester

★ ★ ★ ★ ★

24th Apr, 2017

Very good company, communicated all the way through.  Competitive pricing, I will be using them again in the near future.

- Stewart Greenhalgh

★ ★ ★ ★ ★

6th Jul, 2017

First Class, prompt professional service. I will recommend to other clients.

- Frank Kenny

★ ★ ★ ★ ★

5th Oct, 2017

Excellent  service so far and will be contacting them again for their services.

- Kelly Freakley

★ ★ ★ ★ ★

26th Jul, 2017

Fantastic service from this company at a very reasonable price, would definitely recomend....

- Robert Myers

★ ★ ★ ★ ★

27th Apr, 2017

I used Nova acoustics to sound test my basement flat conversion for the building control certificate

And found them to be professional and friendly. The test was done mid afternoon and I had received by six o'clock the same...

- Stephen Shaw

★ ★ ★ ★ ★

13th Jul, 2017

Excellent service. Would recommend to anyone needing assistance with matters arising from acoustics and noise.

- Rick Parsons

★ ★ ★ ★ ★

29th Jun, 2017

iKoustic have worked with Nova Acoustics for some time now and they are constantly thorough, professional and super helpful in everything they do ... They are certainly our partner of choice ... Rick

- Carl Smoult

★ ★ ★ ★ ★

10th Aug, 2017

Prompt, friendly, efficient, professional... would recommend and use again.

- Gary Oliver

★ ★ ★ ★ ★

20th Mar, 2017

As most of you reading this message are now probably aware  the difficulty of finding guidance and compliance of the part E building regulations is an arduous task. Well search no more! Adam at Nova Acoustics not only talked me through...

- Kate Whitehead

★ ★ ★ ★ ★

27th Jul, 2017

Speedy quote, arranging the testing & report! Seb was really friendly & efficient onsite. Highly recommend!

- David Hope

★ ★ ★ ★ ★

26th Sep, 2017

Came promptly at the requested time. Did the work professionally and in good time and provided the required reports so no issues or problems to report.

- Mark Girdham

★ ★ ★ ★ ★

27th Jul, 2017

NOVA provided a fast and efficient service. They came to carry out the sound tests on my 8 Bed HMO, which was a change of use from 4 flats. Very friendly and professional service. Mark (Hull)

- Simon Phillips

★ ★ ★ ★ ★

4th Oct, 2017

Excellent company, providing a professional service at a competitive price and a quick, hassle free  experience. I would recommend them to anyone.

Simon Phillips  Salisbury Poultry Ltd

- Peter Phillips

★ ★ ★ ★ ★

31st Aug, 2017

Excellent service from start to finish.

Highly professional team who where very accommodating to the team on site and worked exceptional well with everyone.

Having worked with other companies within the same...

- Claire Gannon

★ ★ ★ ★ ★

31st Oct, 2017

Excellent speedy service, Luigi was very proficient and professional at carrying out his job, a real asset to the company. Thank you Luigi. Kind Regards, Ant Mason

Clients we’ve worked with

  • ITV
  • Unilever
  • Sig
  • Leeds University
  • Morrisons
  • Taylor Wimpey
  • City of Stoke On Trent
  • Hambleton District
  • Calvert Trust
  • Aldi
  • Arnold Laver
  • Broadley
  • Engie
  • Gardiner Theo
  • Iggesund
  • Oxford University
  • PepsiCo
  • Richmonshire
  • Savills