Mouth Simu*ator Type 44AA

Product Data an* Specificati*ns

Features/Uses

■     Freq*e*c* *esponse checks of:

○   *e*ep*one transmitte*s

○   communi*ation *icrophones

■     Sound source for acoustic mea*uremen*s

■     Minimum-continuous SPL at MRP:

○   1*0*B re. 20µPa,    2*0H* to 6kH*

○   *ypically 100d*,    *00Hz to 16kH*

■     Complies wi*h Sta*d*rds:

○   IEEE 2*9, 661

○   ITU T Rec. **1

■     Bui*t-in power *mpl*fier or e*t*rnal po*er

amplifier

The G.R.A.S. M*ut* Simulator Type ***A (Fig. 1)

is a *ound source whi*h simulat*s the sound fie*d

around the huma* mo*th at close quar*ers and co*-

pl*es with t** Standa*ds *EEE 269, 661 a*d **U-T

Rec. P5*.

The Type 44AA is f*r *esting te*ephone mout*pieces

as well as o*her *icrophones s*mil*rl* used *n vocal-

co*mu*i*ation net*ork*. At the mouth re*erence

point (MRP), which is 25mm f*om the detachab*e

*i* r*ng (*5mm f*om t** 44AA's mouth), the m*n*-

mum-c*ntinuous e*ualised **g*al it can produce in

?-octa*e band* i* 100dB re. 2*µ*a *n th* frequen*y

range 100** to 16kHz. *ts loud*peaker ac*epts *n

externa* signal e*ther d*rectly or **a its own b*ilt-in

power am*lifie* (w*en power is applied).

C*l*bratio*

Two jig* *re inc*uded for calibrating *he Typ* *4AA

according to a) CCITT P.*1 and b) Fp* IEEE 269.

a) CCITT P.51

The ji* for th*s *ses eithe* a ¼-inch or ½-i*ch

p*e*sur* microphone (e.*. G.R.A.S. Type 40BP

G.R.A.S.

So*nd & Vibrat*on