Astatic CTM 77 User manual

CTM 77
ELECTRET CONDENSER CARDIOID
MICROPHONE
Description
The Astatic CTM 77 is a superior low-noise, electret condenser cardioid
microphone designed for professional vocalists and musicians. The CTM 77
provides the performance and features to satisfy today's most demanding
professionals.
The wide andflat frequency responseof the CTM77provides naturaltransparent
sound quality. The cardioid pickup pattern minimizes annoying feedback (when
usedclose tosound reinforcementspeakers andmonitors) andreduces thepickup
ofunwantedoff-axissounds. Atransformerlesselectronicdesignprovides optimum
low frequency response and low distortion. An effective internal multistage pop
filterminimizeswindand breathnoise. Thelockingon/offswitchprovides excellent
flexibilityof use.
The CTM 77 has a Flex-Form™ hardened steel grille screen that dramatically
resistsdeformation whilegreatlyreducing anyrisk of adverseperformance caused
by a bent or dented ball screen. This unique ability to retain its original shape
assures that the CTM 77 will maintain its attractive appearance.
The CTM 77 features the exclusive (I.N.R.-3™) Impact Noise Rejection system.
Our proprietary rubber shock mount isolates the transducer from the barrel, thus
dramatically reducing cable, stand and handling noise. The need for any external
shockmounting deviceisvirtually eliminated.
The low-frequency response of the CTM 77 may be enhanced by increasing or
decreasing the distance from the sound source. This phenomenon is technically
knownas “proximityeffect”. Nominalor “flat”response is generatedat adistance
of 24 inches or more. However, as the distance to the sound source decreases,
the bass sensitivity increases, providing a solid, robust character.
The CTM 77 is supplied complete with a zippered vinyl protective pouch and a
snap-inmicrophone swivel-mount.
CAD Quality
AllAstaticCTM77microphones areaudiotestedand inspectedpriorto shipment.
Our absolute commitment to quality insuresthat Astaticmicrophones remainthe
BestValuein today's competitive industry.
Operation and Maintenance
The AstaticCTM 77isone of thefinest instrumentaland recordingmicrophones
available. Although it is extremely durable, it should be stored in the zippered
pouch provided to protect it from dust and dirt when not in use.
If the front screen becomes soiled by dirt or residue, it may be cleaned using the
following procedure. Unscrew the front screen assembly and remove the inside
foam windscreen. Wash the foam windscreen using a mild detergent, and let dry
thoroughly. Follow the same method for the grille screen. To clean the mike
housing,use acloth dampenedwithisopropyl alcohol.
IndustrialAudio Products

Specifications
Generating Element:
Electret condenser (Phantom Powered)
Polar Pattern:
Unidirectional(Cardioid)
Frequency Response:
50 Hz - 18 kHz
Output Level:
Open Circuit Voltage:
-55 dB (0 dB = 1 volt per microbar)
Impedance:
500ohms
Dynamic Range:
110 dB
Equivalent Noise Level:
Less than 22 dB,Aweighted
Maximum SPL:
132 dB (1% THD, open circuit)
Powering:
Supply Voltage:
9 - 52 Vdc, positive pins 2 & 3 reverse polarity protected
Current Required:
Less than 5 mA over operating voltage range
Phasing
Positivepressure ondiaphragm generatesa positivevoltage onpin 2
relativeto pin3
Grille Screen:
Hardened Steel Mesh
Case:
Steel and die cast zinc alloy
Finish:
Durablesoft feel,non-slip,midnight black.
Dimensions:
(See drawing on other side)
SPECIFICATIONS FOR CTM 77
TWO-YEARLIMITEDWARRANTY
AstaticMicrophonesarewarrantiedfortwoyearstotheoriginal purchaserfromthedateofpurchasebyOmnitronics,LLCtobefree
fromdefectsinmaterialandworkmanship.Ineventofsuchdefect,productwillberepairedorreplacedatOmnitronics,LLCdiscretion
withanewunitof equalorsuperiorvalue.Thiswillbeatnochargeif deliveredprepaidtoOmnitronics,LLC,together withtheproof
ofpurchaseandaReturnAuthorizationNumber. Theunitwill bereturnedpromptlyprepaid.Warrantyexcludesexteriorfinish,
appearanceitems,or malfunctiondueto abuseoroperation underotherthan specifiedconditions.Consequential orincidental
damagesareexcluded.Serialnumberofproductandoriginalpurchaser’snamemustberegisteredimmediatelyafterpurchase.
Pleaseusetheattachedregistrationformforthispurpose.
Thiswarrantygivesyouspecificlegalrightsandyoumay alsohaveotherrightswhich varyfromstatetostate.Somestatesdonot
allowtheexclusionorlimitation ofincidentalorconsequentialdamagesorlimitationsonhowlonganimpliedwarrantylasts,sothe
aboveexclusionsandlimitationsmaynotapplytoyou.
Note:Nootherwarranty,writtenororalisauthorized byOmnitronics,LLC.
@ 1 kHz
Architects’ and Engineers’ Specification
The microphone shall be an electret condenser type, low impedance with
wide-range frequency response, uniform from 50 Hz to 18 kHz. Output
level at 1 kHz shall be -55 dB (0 dB = 1 volt per microbar). The polar
responseshall showa minimumof -15dB at180 degreesbetween 300Hz
and 1500 Hz. The transducer shall be isolated from handling noise and
othermechanically generated vibration.Themicrophone caseshallbe steel
and die-cast zinc alloy. The microphone shall have a length of 6 25/32"
and a maximum diameter of 1 13/16". The microphone body shall be
finishedinasoftfeel,non-slipmidnight black.Asnap-inclampandazippered
vinylprotective pouchshallbe supplied.
The Astatic Model CTM 77 is specified.
SHIPPING INSTRUCTIONS
Pleasecallourcustomerservicedepartmentat440-593-1111forapre-approvedreturnauthorizationnumberandcarefullyrepack
theunitandreturn itto:Omnitronics,LLC,341HarborSt.,Conneaut,OH 44030
ALLRETURNSMUSTHAVEAPRE-APPROVEDRETURNAUTHORIZATIONNUMBER ORIT WILLBE REFUSED.
IfoutsidetheUnited States,contactyourdealer ordistributorforwarranty details.