Shure 721D User Guide

Made

for

Del Padre

Supply by

222

HARTREY

AVf * EVANSTON.

ILL

-

CABLf

SHUAEYlt40

MODEL

7216,

EVANSTON PHONE

STEREO

OA

8.9000

CHICAGO PHONE

SH

3.1600

CUSTOM MAGNETIC

CARTRl DG

(Stylus

E

Model NZID)

DATA

SHEET

SPECIFICATIONS

RESPONSE FREQUENCY CHARACTERISTICS:

20,000 C.P.S.

OUTPUT VOLTAGE:

5

cm/sec.

CHANNEL SEPARATION:
RECOMMENDED LOAD IMPEDANCE:

nel) for Stereo. 22,000 ohms for Monaural (see

Higher values will produce

response.

STYLUS:

COMPLIANCE:

TRACKING FORCE:

INDUCTANCE:

D.

TERMINALS:

each channel. (See Fig.

MOUNTING:

#3

#2

WEIGHT:

GENERAL:

Cartridge has been developed for use in all high fldelity appli­cations.

constant velocity inputs.

the Model 721D will play Stereo Discs Stereophonically, Monaural
Discs Monaurally, and Stereo Discs Monaurally without excessive

wear and without distortion.

principle offering the following performance features

Shure Model Number N21D.

Radius

C. RESISTANCE:

or

machine screws.

Standard

4

machine screws. ,437 (1l.lmm) mounting centers using

7.9 grams (.28 ounces)
The Model 721D Stereo Custom, Magnetjc Phono

It

has been designed to connect into magnetic and

The Model 721D is completely compatible. In other

The Model 721D utilizes the high quality Moving Magnet

5

millivolts per channel at

.0007”

(0.018 mm) Diamond.

VERTICAL

HORIZONTAL

2

grams optimum.

420 millihenries.

280 ohms.

4

terminals.

1).

YZ”

More than 20 db

47,000 ohms (per chan-

a

slight Increase in high frequency

(

9.0

x

10

per dyne

-6

\

An

independent ground terminal for

(12.7mm) mounting centers using

From

1000

at

1000

cps.

,

connections).

centimenters

:

20

to

cps at

words,

High needle compliance.
Low needle talk.
Low tracking forces.
Wide range frequency response.

is

Magnetic induction from external fields
minimum.

No

magnetic attraction to steel turntables.

MOUNTING:

mounting centers. By using #2 machine screws, the cartridge
can be mounted
portant, during installation, that the line
rartridge be perpendicular to the turntable or record surfaces.

If

no adjustment

ran be used

OPERATION:

results is 2.0 grams. Forces greater than
be used. The 721D should be installed
designed for low tracking forces and having very low friction
at all hearing surfaces.

CONNECTIONS:

arrangement for connections having a separate ground terminal

Cnr

rach channel. (Sre Figure

The 721D Cartridge has standard

on

,437

fll.lmm) mounting centers.

is

available to do this, a paper or metal shim

on

one mounting post to adjust angle of cartridge.

The recommended needle point force

2%

in

The 721D cartridge utilizes a 4 terminal

1).

reduced to a

’ic,”

(12.7mm)

6,

grams should. not

an

It

the front of the

for

optimum

arm

especially

is im-

LEFT

CHANNEL

TERMINAL

LEFT

CHANNEL
GROUND GROUND

TERMINAL

For Stereo reproduction terminal R and its ground ti:rniinal
represent the right channel (outside groove wall). Terminal
and its ground terminal represent the left channel
wall).

To
cartridge to separate amplifiers. To prevent “ground loops” and
hum,
plifier systems.

should be connected to both of the ground terminals at the
cartridge.

cordings, connect the “hot” lead to both
connect the ground or shield lead to both of the ground torminals
marked G.

CAUTION:

nals. Make

SPECIAL NOTE:

such an extremely important part
p,e certain that any replacement stylus

Stereo Dynetic” stylus.

practically immune to damage during normal usage.

CXI‘A

use a 4-lead arrangement connect each section

no

common connection should exist between the two am-

When used with a 3-lead arrangement, the shield lead

No

~

For single channel reproduction of Monaural or Stereo re-

The stylus assembly, when installed in the cartridge is

should be taken to avoid bendinz or distorting the stvlus

TERMINAL DIAGRAMS

FIGURE

other common zround connection should exist.

Do

not make solder connections

all solder connections to terminal jacks provided.

STYLUS

Because the stylus-magnet assembly

1

-

R

REPLACEMENT

in

the overall performance,

and L terminals and

is

TER

MlNAL

(inside grooye

uf

to

cartridge termi-

a genuine Shure

Howcver.

the

plays

L

STYLUS

Stylus replacement

replace
tool) behind the lip
be taken not to deform stylus shank (portion holding stylus tip)
or spring wire in the stylus assembly. (Step 2)-Withdraw stylus
by pulling forward out of cartridge-lift completely out with
thumb and forefinger. (Step 3)-Grasp new stylus between thumb
and forefinger and insert into stylus socket cartridge. (Step
Press stylus into socket until it is firmly seated. Apply pressure
at the front portion
allow the finger to

in damage to the stylus tip.

GUARANTEE:

to be
from the date
structions arc complied with fully. The Guarantee
stylus wear
from abuse or mishandling.

PATENT NOTICE:

3,077,521, 3,077,522, and D187,230. Other patents pending.
Copyright

27A389

(Step

1)-Insert fingernail file

slip

free from electrical and mechanical defects for one year

(2-66)

The 721D Stereo Cartridges are guaranteed

of

shipment from the factory, provided all in-

nor

does it cover damage to the stylus assembly

1966,

Shure Brothers, Inc. Printed in

REP

LACE MENT

FIGURE

is

at

the front of the stylus spade Care must

of

the spade. Care must be taken not to

off

the front of the stylus spade resulting

Manufactured under

2

simple and fast.

(or

U.S.

(See Figure 2). To

a

similarly pointed

doos

not cowr

patents 3,055,988,

4)-

U.S.A.