Krell ksp 7 b owners manual

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REEL

Krell Industries, Inc.
20 Higgins Drive
Milford, CT 06460, USA

THE KSP-7B STEREO PREAMPLIFIER OWNERS MANUAL, MARCH 1, 1989

A. INTRODUCTION

Thank you for purchasing the KSP- 7B Preamplifier. The KSP- 7B is the
latest evolution of KRELLs entry level preamplifier technology.
Many of its design Concepts are similar to our more expensive
preamplifiers and are wholly unique to KRELL. Two important design
features are dual- -mono operation (all active stages are powered by
independent tracking regulators) and the complete absence of any
capacitors in the signal path. The KSP- 7B retains other features
for which KRELL preamplifiers have become recognized: internally
switchable loading for moving coil cartridges and input capacity
rarely found on high- end preamplifiers. All circuitry in the KSP- 7B
is of completely new design, many aspects of which were borrowed
from the top- of- the- line KRS- Balanced Reference Preamplifier. The
most significant of these is the fully balanced output stage.
Balanced circuitry has long been standard for professional audio
equipment. Although it is difficult to explain the technical
advantages of balanced operation, the sonic benefits are clearly
audible. A simple listening comparison between the 0 Output
(single- ended) and the use of both the D and 180 Outputs (balanced
operation) will reveal improvements in all areas of sonic quality
The connection of the KSP- -7B in single- ended and balanced systems
is covered below.

Please read this manual thoroughly before using the KSP-7B.
Installation and operation are simple to understand and perform.
The KSP-7B will provide many years of trouble-free performance.
Please be sure to return the enclosed warranty registration card.

B . UNPACKING

Remove the KSP-7B, power supply and accessories from the shipping
container. Store all packing materials in a cool, dry place for
future use. Inspect the unit for shipping damage; if any damage is
evident contact your dealer immediately. If the unit is in proper
condition proceed with installation. In addition to the
preamplifier and power supply you will find a small "L shaped
allen driver. This is used to remove the top cover to gain access
to the phono section gain and input impedance loading adjustments.

Set-up of the phone section should be completed before installation
of the preamplifier.

Telephone: (203) 874-3139 / FAX: (203] 878-8373 / Telex: 643924

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C. PHONO SECTION SET-UP

Important Note: For the initial adjustment of the phone section the
KSP- 7B should not be connected to its power supply. For adjustments
to the phone section input impedance after the initial set- -up, as
discussed below, please note the following: never adjust any of the
internal switches while the amplifier the KSP- -7B is driving is on.

Moving Coil Cartridges: The KSP- 7B is shipped with the phono
section gain set for moving coil cartridges and a load of 800 ohms

The load can be changed with a set of internal switches. To access
these the top cover must be removed with the supplied allen driver.
At the left-rear of the unit there is a two-position toggle switch.
In the factory-supplied position the switch lever is towards the
rear panel of the unit. If you are using a moving coil cartridge do
not change the switch position. To adjust the input impedance load
for different moving coils use the table below to find the optimum
setting for your cartridge. Follow your dealer 5 or the
manufacturers recommendations first. You can also set the load
using your sonic preferences as a guide. In general, lowering the
impedance will make the high frequencies less prominent and the
overall sound warmer. Higher loads make the overall sound more
vivid and detailed. This is, of course, highly subjective and very
dependent on the cartridge in use.

The various load possibilities are detailed below:

all switches in the open position 47,000 ohms

all switches open except 8 on = 1,000 ohms
all switches open except 7 on = 800 ohms
all switches open except 6 on = 470 ohms
all switches open except 5 on = 250 ohms
all switches open except 4 on = 100 ohms
all switches open except 3 on = 47 ohms
all switches open except 2 on = 25 ohms
all switches open except 1 on = 10 ohms
all switches on = 5 ohms

Moving Magnet Cartridges: If you are using a moving magnet move the
switch lever towards the front of the unit. This lowers the gain of
the phono section to compensate for the higher output of moving
magnet cartridges. It also fixes the load at 47,000 ohms; this
cannot be changed.