of 76
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1/76
HighP
erformancesCross
oversfor
Profess
ionalLou
dspeaker
Systems
andth
eirRealW
orldapplications
B
yMarioDiCola,
AudioLabsSystems,
Milano,Italia
SeniorLoudspea
kerSystemEngineer
A
LMAEuropeanSymposium,Frankfurt,April2009
DerivedbytheAESPaperPresentedbyM.DiCola,M.Hadelich,D.PonteggiaandD.Saronniat121stAESCo
nvention,October2006,SanFrancisc
o,USA
HighPerformancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Multiwa
ysystem
s
Alm
ostthetotalityo
fSoundReinfo
rcement
LoudspeakerSystem
saremultiway
systems
Forsev
eralreasonson
esingletransd
ucercannot
re
producetheen
tireAudioBand
width
Theway
thecrossoverismadeisdeep
lyinfluencing
thefinalperformancesoftheLoudspea
kerSystem
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
8/13/2019 Alma- High Performance Crossovers
3/76
W
hyasystemneedtobemulti-
way?
Howthecross-ove
rshouldbedesigned?
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Subwoofer
Low-MidCone
HighFrequen
cyDriver
Subwoofer
Low
-MidCone
HighFrequencyDriver
W
hyasystemneedtobemulti-way?
Howthecross-ove
rshouldbedes
igned?
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Onesim
plequestion
:
Whath
appenstoth
esignalpassingthrough
aCros
soverFilter?
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Input
Outp
ut
LinearSystem
TransferFunction
time
S
inewavethrou
ghaLinearSystem
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Input
Output
LinearSys
tem
TransferFunction
S
inewavethrou
ghaLinearSystem
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Input
Output
LinearSystem
SinewavethroughaLinearSystem:
effectof
PhaseShiftinFilters
Example1:
Frequencyinside
the
Pass-Band
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Input
Output
LinearSystem
SinewavethroughaLinearSystem:
effectof
PhaseShiftinFilters
Example2:
Frequencycloseto
thecut
frequency
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Input
Output
LinearSystem
SinewavethroughaLinearSystem:
effectof
PhaseShiftinFilters
Example2:
Frequencyoutsid
ethe
Pass-Band
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Sinewavethrougha
LinearSystem:
effectofPhaseS
hiftinFilters
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Desired
TargetResponseatanycrossoverpoint:
asimpleexam
pleofaoptima
lsummationbe
tween2perfec
tly
symmetricalre
sponsesof4th
Order(24dB/O
ct),Linkwitz-Riley
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Howthe
CrossoverApproachcanaffectthe
Loudspeak
erTimeAlignment?
HF
Arrival
Cros
soverPoint
LFEnergy
Arrival
Time
Frequ
ency
WaveletAn
alysisDiagram
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Low
PassFilter
Asim
plesymm
etricCrossover:
2ndOrde
r,L-RType
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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HighPassFilter
Asim
plesymm
etricCrossover:
2ndOrde
r,L-RType
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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4thOrd
erL-RSy
mmetricC
rossover
2ndOrder
2n
dOrder
2ndOrder
2n
dOrder
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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4thOrderL-RSymmetricCro
ssover
Low
PassFilter
H
ighPassFilter
-180deg
+180deg
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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4thOrderL-RSymmetricCro
ssover
Low
PassFilter
H
ighPassFilter
OverallPhaseRelationshipb
etweenthe
twooutpu
tscouldbemorec
learusinga
+3
60-360
phasediagram
-360deg
+360deg
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Driv
ersTimea
lignmentin
differentC
rossoverD
esign
strategies
appliedtoasample2
waysystem
A
ll-PassNetworkCros
sover
(O
nlygeometricIssuesaretakenincountwhile
TimeAligningthedrivers
an
dthenPhaseA
lignmentisusu
allyobtained
delayingthewoofer)
Desired
TimeOrigin
ActualPosition:
effectofLow
PassGroupDelay
Addedtothed
riverdelay
Delayingthe
C
loserSpeaker
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Driv
ersTimea
lignmentin
differentC
rossoverD
esign
strategies
appliedtoasample2
waysystem
D
elayCompen
satedCrossover:
(LPFilterGroupDelayis
takenincountinDriv
ersTimeAlignment)
Type1
Typicallysmallerdelay,butHFPolarity
reversed
Desired
TimeOrigin
Effectof
Filt
erGroupDelay
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Driv
ersTimea
lignmentin
differentC
rossoverD
esign
strategies
appliedtoasample2
waysystem
D
elayCompen
satedCrossover:
(LPFilterGroupDelayis
takenincountinDriv
ersTimeAlignment)
Type2
Typicallylargerdelay,withHFinstraight
Polarity
Desired
TimeOrigin
Effectof
Filt
erGroupDelay
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Driv
ersTimea
lignmentin
differentC
rossoverD
esign
strategies
appliedtoasample2
waysystem
Lin
earPhaseF
iltersCrosso
ver
(O
nlygeometricIssuesneedtobetakenincountwhileTimeAligningthe
driverssinceGroupDelayremainsconstantatanyfrequency)
Desired
TimeOrigin
Delayingthe
C
loserSpeaker
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Crossov
erTechn
iquesco
mpariso
n
Aquickreviewon
relationsh
ipbetwee
n
TimeRes
ponseandTransf
erFuncti
on
Analysisofpracticalapplicationofdifferentcrossover
strategiestothesample
2-waylouds
peakersyste
m
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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IdealSystem
StepResponse
andRelativeT
ransferFunctio
n:
AMinimum
PhaseSystem
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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4thOrderButterworthHighPass(24dB/O
ct)Response.
StepR
esponseandR
elativeTransferFunction:
StillaMinimu
mPhaseSyste
m
TypicalResponsefor
aB
assReflexaligne
dloudspeaker
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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6thOrderButterworthHighPass(36dB/O
ct)Response.
StepR
esponseandR
elativeTransferFunction:
StillaMinimu
mPhaseSyste
m
TypicalResponsefor
aHighPassFiltered
BassReflexlou
dspeaker
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Loudspeak
erSystemUsedfortheSetup
Asimp
le2-way
ProfessionalLoudspeakerSystem
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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StepResponse
SquareWaveRespons
e
Example1:
All-PassNetworkCross
over
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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StepResponse
Example1:
All-PassNetworkCross
over
WaveletAnalysis
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]Angle
[dB]
Level
LevelMark
er:
z=-6d
Ex
ample1
:AllPassNetworkCrossover
VerticalPola
rDirectivityMap
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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6thOrderButterworthHighPass(36dB/O
ct)Response.
StepR
esponseandR
elativeTransferFunction:
NOTaMinimu
mPhaseSyste
m
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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IdealSystem
S
tepResponse
4thOrderHP
M
inimumPhase
System
6thOrderHP
MinimumPhase
System
6thOrderHP
AllPassNetworkSys
tem:
NonMinimum
Phas
e
St
epResponseofdifferentorderCo
mparison
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Example2:
DelayC
ompens
atedTy
pe1
StepResponse
SquareWaveRespons
e
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Example2:
DelayC
ompens
atedTy
pe1
StepResponse
WaveletAnalysis
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]Angle
[dB]
Level
LevelMarke
r:
z=-6d
Example2:
DelayC
ompens
atedTy
pe1
VerticalPola
rDirectivityMap
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Example3:
DelayC
ompens
atedTy
pe2
StepResponse
SquareWaveRespons
e
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Example3:
DelayC
ompens
atedTy
pe2
StepResponse
WaveletAnalysis
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]Angle
[dB]
Level
LevelMarker:
z=-6d
VerticalPola
rDirectivityMap
Example3:
DelayC
ompens
atedTy
pe2
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Examp
le4:LinearPhas
eFilters
StepResponse
SquareWaveRespons
e
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Examp
le4:LinearPhas
eFilters
StepResponse
Wa
veletAnalysis
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]A
ngle
[dB]
Level
LevelMarke
r:
z=-6d
Examp
le4:LinearPhas
eFilters
VerticalPola
rDirectivityMap
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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TransferFunctionsCom
parison
AllPassNetwork
DelayCompensated
Type1
DelayCompensated
Type2
LinearPhaseFilters
24dB/Oct
approx.
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0
-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]
Angle
[dB]
Level
LevelMarker:
z=-6dB
0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0
-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]
Angle
[dB]
Leve
LevelMarker:
z=-6d
0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0
-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]
Angle
[dB]
Leve
LevelMarker:
z=-6d
0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0
-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]
Angle
[dB]
Leve
LevelMarker:
z=-6d
ALL
PASS
DLY
Type1
LIN
PHASE
DLY
Type2
Cr
ossover
Comparison
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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FurtherIm
proveme
nts
Performaces
oftheLinearPhaseFilterprocessed
versioncanb
efurtherimp
rovedinterm
sofvertical
directivitycon
trol
Steeperfilter
functions,in
fact,canbeintroducedw
ithout
additionalphasedistortion
Additionalad
vantagesintermsofPow
erhandlinga
nd
reducedDistortioncanbe
introducedb
ysteeper
crossoverfilters
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0
-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]
Angle
[dB]
Level
LevelMarker:
z=-6d
SquareWaveResponse
WaveletAnaly
sis
VerticalPolarDirecivity
Map
Linea
rPhase
Filters24dB/Oct
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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0 -5
-10
-15
-20
-25
Frequency
[Hz]
500
1k
2k
5k
10k
0
-15
-30
-45
-60
-75
-90
15
30
45
60
75
90
[deg]
Angle
[dB]
Level
LevelMarker:
z=-6d
Linea
rPhase
Filters74dB/Oct
SquareWaveRe
sponse
WaveletAnalysis
VerticalPolarDirecivity
Map
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
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Exampleofpractical
measurement
s
Practical,realwo
rldtransfer
function
measurementsusingadedicatedDual
Channel,F
FTAnalyzer
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Comp
arisonbetwe
enAll-Pass
NetworkandLinearPhaseFilters
settings:Magnitude
andPhaseResponse
All-Pass
Network
LinearPhase
Netwo
rk
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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All-PassNetworkCrossover
settings:MagnitudeandPhase
R
esponseshowingeachin
dividualspeakercontribu
tion
HighFreq.
Contribution
LowFr
eq.
Contribu
tion
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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LinearPhaseFiltersCrossove
rsettings:M
agnitudeand
Phase
R
esponseshowingeachin
dividualspeakercontribu
tion
HighFreq.
Contribution
LowFr
eq.
Contribu
tion
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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MagnitudeandPhaseres
ponsecomparisonBetwe
en:
DelayCompensatedType1,Type2andLinearPh
ase
Filters
LinearPhase
Filters
Delay
Compensated
Type1
Delay
Compensated
Type2
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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An
exampleofh
owDelayCo
mpensatedTechniquesc
anbe
ado
ptedinordertomatchaL
owFrequencyextending
unitto
aLinearPhaseFiltersprocesse
dsystem
UpperBand
Res
ponse
Subwoofer
Response
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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An
exampleofh
owDelayCo
mpensatedTechniquesc
anbe
ado
ptedinordertomatchaL
owFrequencyextending
unitto
aLinearPhaseFiltersprocesse
dsystem
Reduced
Phase
ShiftSub
woofer
Plusupp
ersystem
Crossoverpoint
HighPerform
ancesCrossoverforProfess
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Asim
pledire
ctadvan
tageof
minimizingoverallphaseshift
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ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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An
All-PassCrossover2wayspeaker
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ancesCrossoverforProfess
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ymposium,Frankfurt2009-
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ystems,Milano,Italy
ImagestakenfromtheAESPaper
WrittenbyJustinBairdandDavidMcGrathabout
LinearPhaseFiltersadvantages
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An
All-PassCrossover3wayspeaker
HighPerform
ancesCrossoverforProfess
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ymposium,Frankfurt2009-
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ystems,Milano,Italy
ImagestakenfromtheAESPaper
WrittenbyJustinBairdandDavidMcGrathabout
LinearPhaseFiltersadvantages
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Effectofsumm
ationofthetwospeakerinthe
overlappingarea
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy
ImagestakenfromtheAESPaper
WrittenbyJustinBairdandDavidMcGrathabout
LinearPhaseFiltersadvantages
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Ex
ampleofapplicationo
fLinear
Phasefilte
rstoanexisting
s
ystem.
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ancesCrossoverforProfess
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LF
LF
MF
MF
HF
Sche
maticviewofth
eexisting3wa
ysystem
usedforthepracticalapplication
Exampleo
fapplica
tionofLinearPhase
filterstoanexistings
ystem
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ancesCrossoverforProfess
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LinearPhaseFilters
Processing
OriginalPreset
Processing
3WaySystemPr
ocessing
Comparison
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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LinearPhaseFiltersProcessing
OriginalPresetProcessing
3WaySystemPr
ocessing
Comparison
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Ad
ditionalTestRes
ults
HorizontalPolarDirecivityMap
HorizontalPolarDirecivity
Map
StepResponse
StepResponse
Line
arPhaseFilters
Processing
OriginalPreset
Processing
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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Results
Someadvantage
scanbeachievedwhileprocessingloudspeaker
sy
stemswithLinearPhaseFilters
Reducingtheove
rallphaseshift
ofaloudspeak
ersystemresponse
ca
nresultinbettersoundquality
duetoimprove
dtimecoheren
ce
It
wasfoundthat
goodandencouragingresults
canbeobtained
applyingthistech
niquetoConce
rtSoundReinforcementSyste
ms:
betterarray-abilit
ypropertiesanddirectivitycon
trolcanbeachieved
besideimproved
soundquality
LinearPhaseCro
ssoverisprese
ntlysomething
readilyavailablefor
anybody.Bythewaytransformin
gClassicFilter
sbasedCrosso
verinto
a
LinearPhaseC
rossoverrequiressomeaccuratemeasureme
ntand
so
mecarefulatte
ntion,inordertobeproperlydone
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
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AnExampleo
n
Phas
eRespo
nseLine
arization
ofan
AllPassNetworkSystem
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ancesCrossoverforProfess
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ystems,Milano,Italy
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Mag
nitudeandP
hase
responseofa
n
All-PassCrossover
Lou
dspeakerSy
stem
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ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
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Mag
nitudeandP
hase
responseofa
n
All-PassCrossover
Lou
dspeakerSy
stem
Com
paredtoam
odel
ofa
MinimumPhase
System
MinimumPhaseResponse
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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ystems,Milano,Italy
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Modelofthe1.4kHzAll-Pas
sComponent
Modelofthe1.4kHz
All-PassComponent
Th
ePhaseShiftat
1
.4kHzcould
be
approximatedw
itha
modelofanAll-Pass
Filter
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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Modelofthe1.4kHzInverted
All-PassComponent
The
1.4kHzAll-
Pass
Filte
rcouldbeinverted
viaanFIRInve
rse
Filter
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ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
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All-PassCompensated
PhaseRespo
nse
T
heresultofthe
applicationofthe
inversefilterto
approximate
a
M
inimumPha
se
Response
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ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
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NonMinimu
m
Phase-Shifta
tLF
Fur
therimprovement
ofth
eMinimumP
hase
Response
a
pproximation
is
po
ssibleimproving
TheLFpartof
the
inversefilter
HighPerform
ancesCrossoverforProfess
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AddedLFPhaseShift
Compensation
FinalResultof
the
ImprovedPha
se
Response
Compensatio
n
withtheinverse
filter
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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Impleme
ntationo
fa
DelayCompensatedCrossoverType
viaPassiveFilt
er
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ancesCrossoverforProfess
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Pa
ssiveFilterDela
yCompensatedS
ystem
TotalMagnitud
e,SingleContributionsMagnitudeandPhaseResponse
PassiveFilter+InputEQCombinat
ion
PhaseM
atcharound
CrossoverRegion
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
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PassiveFilterDela
yCompensated
System
STEPRESPONSE
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ancesCrossoverforProfess
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Pass
iveFilterDela
yCompensated
System
Beamwid
th,DirectivityIndexandPolarMapsofBothPlanes
HighPerform
ancesCrossoverforProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
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Than
kYou
forProfess
ionalLoudspeakers,ALMAS
ymposium,Frankfurt2009-
MarioDiCola,AudioLabsS
ystems,Milano,Italy