Leak varislope 2 stereo owners manual

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'VARISLDPE 2 BTERED'
PH E-AMPLIFIEH

""""""""" INBTALLATIDN - anEHA'rtaN - MAINTENANCE

The VARlSLOlE 2 STEREO' pre-amplitier is de' ed specifically for use with the 'STEREO 20 or
STEREO 60' power amplifiers. though it may lso used with any combination of two LEAK monaiiral
power amplifiers ( TL/IZ , TLV/IO, TL,|2 PLUS. "IL/15 PLUS . lL,5tl PLUS 'i,

CONNECTING THE 'VAFIIBLDPE 2 STERED' DRE-AMPLIFIER

I. In) This unit may be used free-standing on a table. or it may be mounted on a panel of any thickness. through
acut-out of mg" >1 3} (27 cms, x 9-85 ems). To mount on a pane remove the rubber feet by pulling
smartly out of their retaining holes: pass the body of the pre-anip -r through the cut-out uittil the front
plate butts against the panel. then pass the l shaped bracket over the back of the preamplifier and Iix
it by passing the wing-screw through the hole in the brackt and into the threaded hank-hush iii the centre
of the rear panel on the pre-amplilier. Tighten the wing- rcw just enough to prevent the metal backing
of the front plate from slipping on the panel.

[III A grey or brown multiple cable of Mt. (l- nteircsi is supplied [or connecting the VARISLOPE 2
STEREO to a LEAK stereo power amplilier. l be male plug on this cable [its the socket 0n the stereo
power amplifier marked PRE-AMP'. The female plug on the cable fits the male socket oit the
' VARISLOPF. 2 STEREO marked FROM AMPLIFIER I Longer cables can be supplied to special
order. tip to a maximum of loft. (5 metres].

(c) To uiable yoti to control tlte power antplilier front the VARISLOPE 2 STEREO' a switch is

incorporated in the VOLLME ' control. To make use ol this facility a Z-corc flexible cable is supplied
with the VARISLOIE 2 STEREO': one end of the cable is titled with a plug which inserts into the
socket marked SWI'I'CH' on the rear of the VARISLOPF. Z STEREO: the other end of the Cable
must be passed through the rubber groittniet marked 'SWITCH CABLE on the associated LEAK stereo
power amplitier. knotted behind the grommet. and the two barcd ends connected to the term .15 marked
SWITCH' (situated underneath the mains transformer). alter removing the wire link Joining these
terminals.
We strongly recommend that the power amplitier should be eartlied ' tgroundel). ll' excessive hum is
experienced. particularly with the power plilier not carllicd (grounded) this can be reduced by
reversing the tiiaitis input leads to the power amplifier. Reversing the SWITCH ' connections will not
be effective.

(ti) When the VARISLOPE 2 STEREO' is used with two l.F/\K single channel amplifiers the multiple inter-
connecting cable should be connected between the male socket marked FROM AMPLIFIER ' on the
' VARISLOPE 2 STEREO and the socket marked PR E-AMI" on one of the LEAK power amplifiers.
which becomes the left-hand channel. An earth connection should be taken to the third pin on the
removable plug portion of the AL. POWER' connector on this left~hand channel power amplilicr.
lhc ' ' 'al socket marked OL'TPUT R ' on the VARISLOPE 2 STEREO should be connected via
a : lied coaxial cable to the ocial socket on the second power antplilicr ntarked PRE-AMP': the
screening being connected to Pin l and the lite inner conductor to Pitt 8, This power amplifier becomes
tlte riglitdtand channel. and will automatically be earthcd via the screening of its co-axial input cable;
to ensure freedom front hum (due to earth loops) no ditional earth should be made.

NB. Only one LEAK power amplifier should be connected to the SWI'ICH setkct. The other power
amplifier must be switched separately.

OPERATING 'I'HE IVI\I=IIBLDPE E STEHED'
2. BALANCE CONTROL
The BALANCE' control allows you to compensate for ditlercnccs in scnsit ity between loudspeakers. or
the L and R ' side of any stereo input device The gain in each channel is identical when the pointer on
the BALANCE' control knob is vertical. A (urtlier function of the BALANCE' control is mentioned
in paragraph l2.

3. VOLUME CONTROL

'lhc prc-sct input volume controls on the rear panel of the VARISLOIE 2 SI EREO' should be adjusted so
that a normal level of reproduction is ohtaiitable with the main VOLUME control set to 10 o'clock or
higher. It is better not to listen with the VOLUME ' control below [0 oclock 2 as the channel balance below
this setting may vary by itiore than ldb.

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4. FUNCTION SELECTOR
A four position switch allows the choice of:- .

tn) MONO. This parallels the L and R circuits. enabling a stereo pickup to play mono LP records.
(II) STEREO.

tr) INPUT R (mono. connects both channels to the R '
(II) INPUT 1. (mono. connects both channels to the l.

input device).
Input device).

5. llli M

The VARISLOPE 2 STEREO pre-amplilier has an extremely low hum level. which can be checked by
removing the input plugs and turning up the VOLUME control. The connection of any input device to
the input sockets will lower the input impedance antl should. therefore. reduce the hum level. If the hum
level increases on making these connections. the cause of the hunt must lie outside the pre-amplitier. and our
instructions on the connection of the input devices should he read carefully in an attempt to locate the cause
of the bum.

(L HISS

With the input control switched to .MlC' TAPE HEAD' or PICKUP and the VOLUME control
at maximum. a certain amount of hiss will he heard. This hiss Is as low as is possible to obtain at the present
date. and it is inherent in high-gain vacuum- -tube ampliliers

CONNECTING STEREO PICKUP.

7. (a) The greatest care has been taken in the design of this preamplifier to ensure that any pickup generally
available in the world can be connected to give optimum results. i.e. the highest quality obtainable from
the chosen make of pickup. Our prime aim is for you to obtain optimum results from the pickup of
your choice.

(Ii) The pickup should be connected via screened c.) al cables to the sockets marked PICKUP at the
rear of the VARISLOPE 2 STEREO ' pre-amplil r. as shown below.

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to) Some pickups will be litted with two inner conductors covered by one outer screening: in this case the
user should make sure that the screening of both inner conductors is maintained right up to the plugs fitting
the sockets marked PICKUP, as shown below.

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(d) We know frontexpcriencc that the main troubles encountered by the music-lover at home are with the
reproduction of records. There are five major reasons for these troubles; ,

(i) No record can possibly give perfect reproduction and many records tperhaps the majority) contain
noticeable distortions due to imperfections in recording andor processing. These imperfections may
show up as r'allle. high surface noise recorded hum and rumble and recorded wow Shrill
treble may be due to a poor record. and/or due to a pickup having its high frequency resonance
within the audible range.

tiii No pickup is perfect and the majority hat perlormances very IIIm-II below those which are attainable.

(iii) Hum. This often arises because insufficient attention is given during the design of a pickup to the
commonly-found circumstances in thch it will operate. Le. near an electric motor and near a power
amplifier. Hum can also arise from incorrect connection ol the pickup by the user.
if hunt is to hekept to a minimum the outer sereeninbI of any pickup wiring should either have an
Insulated eovcrIn . or It should be prevented from touching any metal on the motor. motorboard or
anywhere else. he outer screening Inml "Ill be used for eartlIing any part of the motor and turn-

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