Bryston .58 Preamplifier, .5B Preamplifier Operating Instructions Manual

.

~~

-

.

.

~~~~~~~~

.

8RYSTON .58 PREAMPLIFIER

OPERATING INSTRUCTIONS

p==:

••

c=YVRNT,;BLE

Iliiiiiiiiliilol

I~

I

PHONO

TUNER

CD!AUX

•

t

t

-=-

50

Hl

2 i 20

Hz

')

J J

')

r

,",vow

a

500

'"

H

TAPE

LOW

FILTER

SELECTOR

S

WITCH

SWITCH

OCJD0DOIJJ

MODEL

.58

SIGNAL

FLOW

AND

SWITCHING DIAGRAM

TAPE

DECK

-OR-

AUDIO PROCESSOR

I:

11111.

11111

A~~~~I~R

11111

. 1

1111

:]

t t

t

TAPE

IN

TAPE

OUT

MAIN

OUT

AC

RECEPTACLES

I

FUSE

~

o

-=-

VOLUME

POWER

PILOT

SWiTCH

C

ON

TROL

SWITCH

TAPE

B

ALA

NCE

MUTE

CONTROL

SW

ITCH LIGHT

I

I

I

I

I

I
I

)

/

/

(

RELAY

V+

IV-

TO

AMPLIFIER

MODULES

SWITCHED IIUNSWITCHED

Q

TO

OPPOS

ITE

CHANNEL

POWFR AMPLIFIER

-

'"

.

TAPE DECK - \

6

-OR-

r

a

I11111

\\\\\'~IIII\\

\\\111

~\

0

=--

••

TURNITABLE

I

1"\~21

\

~~

I

+

+

I"~[i

l

+

TAPE DECK

-OR-

AUDIO PROCESSOR

+

t

POWER

AMPLIFIER

[~mlll

0

111111~nnll

0

IIIIII

~l

~-------------------,

INPUT

INPUT

2 INPUT 3 INPUT 4

TAPE

OUT

MAIN

OUT

BALANCED OUTPUTS'
REPLACE

AC

'

RECEPTACLES

ON
BP4/ BP4.2/BP5
MODELS

ONLY

AB/BP4

-

.5B/BP5

-

BP4.2

-

50

Hz

&:

500

Hz

5B/BP5

ONLY

AU

X

PHONO

LINE

1.

2120

Hz

TUNER

TUNER

LINE

2-

CD

CD/AUX

LINE 3

INPUT

INPUT 2
INPUT 3

INPUT 4

SEUECTOR

SWITCH

NOTES: D

iagram

depicts 1 channel

only

"

MONO

and

MUTE

switches

combined

on

.5B/BP5

• -

balanced

inputs

on

BP4.2.

Monitors

Line 1

only.

TAPE
TAPE

LINE 4

'- '1

,

RELAY

r-----'

.D-----------r

,

,

,

:1

I:

i

I i 'l'

BALANCE MUTE
CONTROL

SWITCH

I

VOLUME

CONTROL

/

(

TO

OPPOSITE CHANNEL

/

/

/

/

/

./

~-------------------~

,

, MODELS
,

AB/.5B

:

120V

,

ONLY

SWITCHED

£

UNSWITCHED

I'

£ :

F

US

E

o

PILOT

POWER

UGHT

SWITCH

MODEL

.4B/BP4/BP4.2/.5B/BP5

Signal Flow

and

Switching Diagram

o

The Bryston Model .5B is a
basic signal preamplifier with
switching

facilities

for

a

simple, high

quality

sound

system,

including

phono,
tuner, tape deck and CD/aux­iliary. The included diagram
will illustrate the switching
functions

of

the

Bryston

Model .5B preamplifier .

TAPE

MONITOR FUNCTION

The tape

monitor

switch

(labelled

"Tape"),

allows
monitoring, through the main
outputs, of whatever appears
at the tape inputs. Thus,

if

a
tape recorder has a third,
playback head, this will allow
the audition

of

a tape recor­ding as it is being made. Simp­ly plug the

output

from the

playback head

to

the "Tape

In-

put"

jacks.

Pressing

the

switch activates the

monitor

function.

TAPE

LOOP

The

tape switch also allows

for external processor looping.

A

noise

reduction

unit,

equalizer or other audio

ac-

cessory is fed from the "Tape

Output' jacks, (which exit
prior to the volume control).

The processed

output

from
the accessory is fed back into
the tape inputs. The tape
switch then allows the inclu­sion

of

the processor in the

signal path when pressed,

or
its exclusion from the signal
path when left in the 'Out'
position.

LOW FILTER

The inflection point of the
rumble filter has been chosen
at 31.7Hz

to

correspond to the
lowest signal frequencies like­ly

to

be

found in recorded

music, and

to

a suggested
revision to the RIAA recording
curve for

LP

discs. For these
reasons, and for the more im­portant reason

of

avoiding low
frequency transient overshoot,
ringing and phase misalign­ment, the low filter is a
"minimum"

type,

with

a

6dB/octave

slope

below

cutoff. This is quite effective in

reducing

subsonic

woofer-

wobble and

its

attendant inter-

modulation effects, however,

since the most problematic
turntable and warp-induced

rumble frequencies, in the
area of 2-5Hz, are reduced

an
average of about 20dB or a
factor

of

100

in

terms

of

power

demand. The low filter

switch
is active in the 'In' position,
and affects only the phono in­puts.

MUTE SWITCH

The listener often is called

momentarily

away

from

critical listening,

to

answer
the phone for example, and
wishes to reduce the gain for a
short time without disturbing
the volume control setting .
The

mute

switch

reduces
preamp gain by 20dB. Thus the
music may still

be

heard, but
at a background level. This is
also

useful

for

changing

records, cueing the stylus
manually

to a particular song,
cleaning the stylus with a
brush, etc. The mute switch is
active

in the 'In' position and

affects

only the main

outputs

without

disturbing the tape

outputs.

MONO

FUNCTION

Occasionally a system will

display

some offset in gain

favouring one channel over the

other

due

to

slight differences

in speaker

efficiency

, dif­ferences in room loading, or a
somewhat

off-center listening

position

dictated

by

room

decor

. Thus it is convenient

to

"mono"

the signal to obtain
the most unambiguous center
image,

convenient

to

ad-

justing

the balance control.

For reasons

of

simplicity

,
rather than having a separate
switch

for

this

function, the

"Mute"

switch a Iso connects

the

two

channels in Mono. Ob­viously, the listener may wish
to

advance the volume control

to

provide sufficient level for
establishing center image. Do
not

forget

to

reduce

the
volume control again before
deactivating the mute

switch

in

this

case,

or

you may be
startled by the sudden in·
crease in sound level. The
balance control is a tailored

in-

flection

type which has very
gradual action near the center
of

rotation

for

fine

ad-

justments

to the left-right

balance of the stereo image.

ACCESSORY OUTLETS.

The .5B inc ludes

two

3·prong grounded.

120

volt

receptacles on the rear panel ,
one switched. one unswitch ­ed

. Please observe the

caution
printed below the receptables
regarding

maximum

power
draw from these outlets. Large
power

amplifiers, especially

including

the 8ryston models

38

and

48

should not

be

plug-

ged

into

these receptacles. To

do

so

may

damage

the

preamp's power

switch. It

is

permissib

le

to

plug

the

Bryston

2B·LP

into

these

outlets

, however, or any class

AB

amplifier

up

to 50, (or class

A

amplif

ier up to 15)

watts

per

channel.

In

general , it is inad-

visable to

switch

large power

amplifiers

on and

off

by the

swi

tch

in a preamplifier, for

the above reason, and also

because it is likely to cause a
fluctuating

voltage·drop on the

preamplifier's

line cord, which

in

worst

case

conditions

can

become an audible problem.

TURN

ON DELAY

The Model .5B

contains

an

output

shunting relay with

an

approximate

3-second delay at

turnon, to

allow

any transient

thumps

to

settle

. The relay

opens

instantly

when

the

preamp is

switched

off

to

pre­vent any power-supply decay
artifacts

from appearing at the

outputs

. The relay

has

multi·

pie gold

contact

faces per

channel for

maximum

long

term

reliability

, and

does

not

appear in the signal

path

when

the preamp is operating.

The

Point-five-B

has been

designed

from a rational,
function-oriented ideal of max­imum

musical

accuracy,

with

an

absolute

minimum

of

uselsss

gadgetry

or

ex-

traneous

controls

. The signal -

handling

circuit

is novel and

fundamentally

correct, both

electronically

, and more im·

portant ,

sonically

. We believe

you will find a renewed sense

of

awareness

of

the musical

enjoyment in your

music

col-

lectio

n,

played through your

Bryston

preamplifier.

Even
your tuner will sound cleaner
and

more

musically
transparent than you may
have exprienced before.

Please do not

hesitate

to
write us if you have any ques­tions

or

comments

about any

of

our

products. Your opinion

is important to us.

57 WESTMORE DRIVE, R8<DALE, ONTARIO,

CANADA

M9V 3Y6 TELEPHONE: 416-745·1800, TELE

X: 06·989548

IN THE U.S.

A.

TELEPHONE: 802·

223-B159

e.

G. J/B5