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The Datafile PD-CD 1 Issue 2
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PDCD-1 - Issue 02.iso
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utilities
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004
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_effex
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!Effex
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UserGuide
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1993-04-08
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F0110030
9[..................................................]001
üëDocumentationfor!Effex
ÇEffexwrittenbyandcopyrightPaulMason
Likemostcomputersnowadays(withtheexceptionofthePC),
Acornmachineshavetheabilitytoplayhighqualitysound.This
isachievedbyliterallycontrollingthespeaker.Asampleis
basicallyrawdatadescribingthevariouspositionsofthe
speaker.Bysuchlow-levelcontrolasthis,itispossibleto
createverynearlyanysound.Suchsamplesareobtainablefrom
severaldifferentsources.ManygoodsoundscanbefoundonPD
discs,andAmiga/STPDhasawealthofsamples.Alternatively,if
youhaveaccesstoasampler,almostanysoundcanbecaptured
andsavedontodisc.Theothermainoptionistocalculateyour
sample,usingmathematicsoroneofthegoodcommercialprograms.
Whicheverwayyouobtainyoursample,youwillneedtoplayit
backandifyouaremoreadventurous,manipulateit.
Effexisaversatilesampleeditor.Itallowsfullycontrollable
editingofthesample-cuttingandpasting,mixing,andawhole
hostofotherspecialeffectsthatyoucanusetoaddalittle
somethingtothesound.
üThemainwindowÇ
WhenyouloadasampleintoEffex,byeitherdouble-clickingon
itsicon,ordraggingittotheEffexicon,themainwindow
willopen,withaviewofthesampleatthebottom.Onthefar
rightofthewindow,justabovethesampleviewer,youwillfind
azoomerbox.Thisoperatesinthestandardway-liketheoneon
!Drawor!Paint.Notethatitisnotpossibletohavethezoom
settolessthan1(ie.therightnumberlargerthantheleft).
Ifyouzoominonthesample,youcanmoveaboutinsideitby
draggingthescrollbaratthebottom.
üSelectionsandthecaretÇ
Inordertoeditthesample,youshouldfirstknowhowtoselect
anarea,andmovethecaret.Theselectiondefineswhatisgoing
tobeactedon,andthecaretspecifieswhereanydestination
data(eg.amoveorcopy)willgo.
Toselectanarea,click(select)whereyouwantthestarttobe,
anddragthepointertowhereyouwishtoendtheselection.To
changeaselection,click(select)ontheendyouwishtochange
anddrag.Ifyouclick(select)insidethesampleview,the
nearestendoftheselectionwilljumptowhereyouclicked.
Tocleartheselection,click(menu)overthewindow,andchoose
'Clearselection'offtheselectionsubmenu.Alternatively,press
CTRL Z.
Toselecttheentiresample,choose'Selectall',orpress
CTRL A.
Whenyoumakeaselection,theiconseithersideof'Sel'onthe
mainwindowwillchangetoreflectthepositionwithinthesample
Çofyouselection.Thelefticonisthestart,therightisthe
end.Youcanentervaluesintothesetochangetheselection.
Tozoomtheselectionsoasitfitstheentirewindow(if
possible),pressZorchooseZoomfromtheSelectionsubmenu.
Tomovethecaret,simplyclick(adjust)intheview,andared
linewillappear,markingthecaretposition.Again,theiconby
theword'caret'willchangetoreflectthecaretposition.You
canenteravalueintoherealso.Alternatively,clickontheup
ordownarrowstomovethecaret(veryslightly).Pressingshift
whileclickingonthesewillstepthecaretby16.(Notethat
shifthasthateffectonanyup/downarrows-thevaluein
questionstepsby16).
Fulldetailsaboutthesample,selectionandcaretpositionscan
beobtainedfromtheSamplewindowintheMiscsubmenu.
üOperatingonaselectionÇ
Allmenuselectionsdescribedinthissectionaremadefromthe
Selectionsubmenuunlessotherwisestated.
Onceyouhavemadeaselection,youmaywishtomove,deleteor
copyit.
DeletingaselectioncanbeachievedbychoosingDelete,or
pressingCTRL X.
Movingaselectiontothecaretpositioncanbedonebychoosing
MoveorpressingCTRL V.
Copyingcanbedonewithtwoeffects.Tocopytheblock,
insertingitatthecaretposition,choosecopy,orCTRL C.To
copyit,overwritingdataatthecaretposition,choosecopy
over,orCTRL Y.
Mixingenablesyoutooverlaypartsofthesample.If,for
example,youhaveinyoursample,asoundofamotorbike,and
lateron,asoundofascream,theycanbemixedtogether,to
producethesoundofamotorbikewhilesomeoneisscreaming.To
mixtheselectionwithdataafterthecaret,chooseMix.Tomix
datadirectlybeforethestartoftheselection,choosepre-mix.
Tomixaftertheendoftheselection,choosepost-mix.
üPlayingthesampleÇ
Inordertoplaythesample,bringupthemenu,andchoosePlay
fromthePlayingsubmenu.Alternatively,pressCTRL P.Ifthe
sampleplaystoofastorslow,changethesamplerate.Thiscan
bedonebyalteringthevaluebythewordKHz,orthevalueby
thewordî╡sÇ.IfyouincreasetheKHzvalue,thesamplewillspeed
up(onreplaying).The╡svalueisinverselyproportional,ie.
increasingitwillslowdownthesample.
Toalterthevolume,clickontheup/downarrowsaboveandbelow
thevalue127.Alternatively,enteranewvalue.Ifyoucannot
hearanysound,thespeakeriseitheroff,orthemastervolume
Çlevelistoolow.PressF12andtype:
*SpeakerOn
*Volume127
Tostopplaybackofasample,chooseStopfromthePlaying
submenu,orpressCTRL S.Duringplaybackitispossibletoalter
thevolume(asnormal),andalso'bend'thepitch.Thelatteris
achievedbyclickingonthePupandPdownicons,orchoosing
Pitchupordownfromtheplayingsubmenu.Maximumvolumecan
instantlybesetbychoosingMax.volumeorpressingCTRL L.
Ifyouwishtoseewhatpartofthesampleisbeingplayed,
choosePlaytrackingorpressCTRL T.Thiswillthenmovethe
caretinsyncwiththesample.Clicking(adjust)anywhereinthe
viewerwhileplaytrackingwillplayfromthatposition.Oncethe
samplehasstopped,youcanmovethecaretanywhereandpress
spaceorchooseContinue,andplayingwillstartfromthecaret.
Notethatifyouhavefinishedplayingaselection,theplay
cannotberesumedwiththecaretaftertheendoftheselection.
Toplaybacktheselection,choosePlayfromtheselection
submenu,orpressCTRL E.
üSampletypesÇ
Atpresent,Effexsupportslogarithmic,signedlinearand
unsignedlinearsamples,andcanplayallofthese.Thefollowing
fileformatsareinterpretedbyEffex:
LogSampl(&631):loadingthisforcesthesampletypetoLog
SgnSampl(&632):loadingthisforcesthesampletypetoSigned
UnsSampl(&633):loadingthisforcesthesampletypetoUnsigned
Effex(&634):theformatwhensavedisrestored,asisthe
selectionandcaretdetails,andsamplerate.
Armadeus(&D3C):sampletypeissettounsigned,andsamplerate
isrestored.
Anyotherfiletypedefaultstounsigned.
Thesampletypecanbechangedbychoosingtheappropriatetype
fromtheMiscsubmenu.
ToconvertfromaLogsampletoSignedlinear,chooseLog2Lin
Toconvertviceversa,chooseLin2Log
TochangefromSignedtoUnsigned,choose(Un)Sign.
üEffectsÇ
AllmenuselectionsdescribedherearemadefromtheEffects
submenuunlessotherwisestated.
Ifyouwishtoaddaspecialeffecttoyourmarkedselection
only,ensurethe'Selection'option(atthetop)isticked.
Otherwise,theeffectwillbeenforcedonthewholesample.
Ç
Reverse:reverses(flips)thechosenarea
Silence:amplifiesthechosenareaby0
Fadein(CTRL I):fadestheareainfromquiettofullvolume
Fadeout(CTRL O):fadestheareaoutfromfulltoquiet
Amplify:amplifiestheareabythegivenpercentage
Quieten:amplifiestheareaby(10000/value)percentage
ie.Quieteningby200%willcounteractanamplificationof200%
Eor:eorseachbyteoftheareawiththegivenvalue
Add:addsthegivenvaluetoeachbyteofthearea(movesthe
sampleupordown)
High-Ampfilter:clipsanyvaluesthatexceedthegivenvalue
Low-Ampfilter:clipsanyvaluethatfallbelowthevalue
Corefilter:Seebelow
LowFreqboost:Boostslowfrequenciesandvolumes
HighFreqboost:Bootshighfrequenciesandvolumes
ModulationandEcho:seebelow
üFilters
ÇHA:ifa+precedesthevalue,thecentre(normally128)is
addedtothevaluebeforeclipping
LA:isa-precedesit,itissubtractedfromthecentre
Corefilter:ifanyvaluefallswithinthegivenvalueeither
sideofthecentre,itisroundedofftothecentrevalue.If
usedcarefully(andsubtley),thisfiltercanremovenoisefroma
sample,withoutaffectingthequalitytooseriously.
üModulationÇ
Tomodulatethesample,enteraformulaintooneofthefive
spaces(thetopmaycontainatwo-wayscramblingformula).The
followingvariablesareguaranteedtobedefined:
X=xpositionwithinsample
Y=value
Z=previousvalue
TheformulashouldoutputanewvalueforY,ie.foreverybyte,
X,YandZaresetup,andtheformulaiscalled,storingthe
resultbackinthesample.
PleasenotethatmodulationisverySLOW!
üEchoÇ
Threedifferentechoesareprovidedtoenhanceyoursample.By
changingtheecholength,different'depths'ofechocanbe
obtained.Theechostrengthwillaffecthowpowerfultheechois.
Echostrengthsabove100%arenotrecommended.
Echo(orpressingE)isthesoftestecho
ÇFlangeecho(F)producesarehard,metallicecho
Hallecho(H)producesacomplexecho
Apipe-effectechocanbeachievedbyastronghallecho(80%)
withlength64orthereabouts,andthenrepeatedLFboostsof
about2-8.LFboostsoftenhavetheeffectofsmoothinganecho
(oranysound).
üSavingthesampleÇ
Tosavethesample,opentheSavesubmenu.Fromthis,uptothree
savewindowscanbeopened.SavingfromtheLogsubmenucanonly
beachievedwhenthesampleislogarithmic.Itwillsettypeits
filetoLogSampl(&631).TheUnsignedandsignedsubmenusoperate
inasimilarway,butsavingasunsignedorsignedfiles.
SavingfromtheEffexsubmenucanbeachievedatanytime.As
wellassavingthesample,itwillstoredetailsaboutsample
rate,selectionsandcaretposition.Italsostoresthesample
rate.
SavingasanArmadeusfileisonlypossiblewithanunsigned
sample,andsavesthesampleratealongwiththesample.
üProgrammingtechniques
ÇTheWimpfrontendforEffexiswrittenentirelyinBASIC,using
machinecodeonlyforthemovementandspecialeffects(except
modulation)routines.ThismeansthatEffexiseasilycustomable
foranexperiencedprogrammer.Thisdoeshoweverhavetheslight
drawbackofslowredraws(eventhisisn'ttoonoticeableonan
Arm3).Themenustructureissuchthatextraoptionscanbeadded
later-indeed,Iwouldbeinterestedinimprovements/additions
madetoEffex.
üKnownproblemsÇ
Effexhasseveralknownproblemswhichwillhopefullyberemoved
inafutureversion.
Savingto!Editisonlypossibleifyoufirstopenawindowand
thendragtheiconintothat.
Inhighmagnification,theselectionmaynotalwaysbedisplayed
properly.
Duetotheway256-colourmodesorganisetheirpalette,the
selectionmaynotbedisplayedatallinsuchmodes.
Itisonlypossibletozoominontheselectionwhenin1:1zoom.