Gryphon Mephisto Solo User Manual

Mephisto Solo

Owner´s Manual

Table of Contents:

Introduction....................... 3

The Gryphon....................... 3

The Man.............................. 4

Made in Denmark............... 4

Musical Objectives.............. 5

The Gryphon Master Tape

Collection............................ 5

Design Principles................ 5

Exterior Design................... 7

Manufacture and Assembly. 8

Using Your Gryphon

......... 8

AC Voltage.......................... 8

Burn-In and Warm-Up.......... 8

Balanced Connections........ 9

Choice of Cables................. 9

Care and Maintenance........ 9

Gryphon Mephisto............... 10

Sonic Excellence................. 10

Circuit Topology.................... 11

Class A................................. 11

Protection............................. 13

Exterior................................. 13

Installation............................ 14

AC Power, Placement.......... 14

Power Cords, AC Polarity..... 15

Front Panel Functions............ 15

Green Bias............................ 16

Rear Panel Functions............ 17

Protection system.................. 17

Fuses, .................................. 18

Troubleshooting ................... 19

Warranty................................ 20

Introduction

Welcome to the global family of
proud owners of fine audio com­ponents from Gryphon Audio
Designs of Denmark. Your new
Gryphon unit has been painstak­ingly designed to re-create the
sound of live music taking place
in its original recorded space.
Every Gryphon product is
designed to cater to the needs of
the most discerning music
enthusiast with sumptuous
styling and superb user-friendli­ness which elevate it above the
mundane world of con­ventional audio compo­nents.

As audiophiles, the
members of the
Gryphon design team are con­stantly reminded to keep their
priorities straight. We are not
involved in “hi-fi” for its own
sake, but strictly as a means to
an end, in the service of our life­long love of the live music expe­rience in all its sonic and emo­tional glory.

Our higher goal is to bring to the
listener a “You-Are-There” sen­sation. In taking up this chal­lenge, the Gryphon designers go
back to basics to analyze the
essential nature of the live music
experience. For us, an aware­ness of soundstaging, ambience

and concert hall dimensions are
necessary components.
Dynamics and an unambiguous
sense of instrument location
even in the loudest passages
are also high priorities. To
achieve these objectives,
Gryphon products offer excep­tional speed and agility along
with seamless coherence in the
time domain.

Since 1985, Gryphon Audio
Designs has quietly gone about
the business of creating fine
home audio components. We

know that you will appreci­ate and enjoy the benefits
of our accumulated expe­rience and share our abid­ing passion for music.

The Gryphon

In Greek mythology: A fabled
creature, half-lion and half­eagle, combining the power of
the “King of Beasts” with the
grace of the “King of Birds”. The
guardian of the source of gold
and protector of the Dionysian
cup of infinite wealth.
In the real world: An acclaimed
Danish audio engineering com­pany employing cutting edge
technology and common sense
in the pursuit of the purest musi­cal experience. We feel that the
gryphon is an appropriate sym­bol for our high sonic goals.

3

The Man

Gryphon Audio Designs is the
brainchild of Flemming E.
Rasmussen and the fulfillment of
a lifelong dream to allow the
purest essence of the live music
experience to be recreated in the
home environment.

Rasmussen holds a degree in
painting and graphic arts from
the Aarhus Art Academy,
Denmark. During his studies,
Rasmussen developed close
relationships with the local music
community and designed many
LP covers and concert posters.
After graduation, he taught pho­tography and painting and
designed textiles, before found­ing 2R Marketing, which quickly
became Denmark’s leading High
End audio import company.

Gryphon Audio Designs was
founded in 1985 as an offshoot
of 2R Marketing, The first prod­uct, the now legendary Gryphon
Head Amp, grew from a one-off
spare time project developed
only for the designers’ own home
systems. Although the Gryphon
project was initially strictly a
hobby, not an actively pursued
commercial venture, demand
generated by reviews and word­of-mouth led to the formal estab­lishment of Gryphon Audio
Designs as a separate corporate
entity.

Following the immediate suc­cess of the Gryphon brand, all
import business was phased out
in 1993, so that Rasmussen
could dedicate his efforts entire­ly to Gryphon.

Made In Denmark

Every product from Gryphon
Audio Designs is designed and
built in Denmark. This is much
more than just a geographical
fact. It is also a seal of approval,
a stamp of quality. Living in a
region with no natural resources
(no oil, coal, precious metals,
etc.), the Danes have learned to
rely on their quick wits and
skilled hands. Innovative tech­nology, beautiful craftsmanship,
pride in one’s craft and a keen
eye for attractive design are
some of the long-standing
Danish traditions which are dis­tilled to their finest essence in
every unit that bears the
Gryphon name.

Musical Objectives

While scientific method and
sophisticated technology play an
important role in our electronics
design work, at Gryphon we
never lose sight of the fact that
the keen ears of an experienced
listener are the most crucial “cal­ibration tools.” Therefore, every

The Gryphon Head Amp 1985

4

Gryphon product exists for one
simple purpose: to bring the user
closer in the never-ending quest
for a more natural and convinc­ing musical illusion.

Every Gryphon design has been
built to cruise effortlessly through
even the most demanding musi­cal passages, regardless of vol­ume level, with a musical pres­entation defined by supreme
articulation and immediacy, sub­tle dynamic shading and razor­sharp focus. Refinement and
delicacy are combined with
power and authority for a natu­ral, involving listening experi­ence.

The Gryphon Master
Tape Collection

In the Gryphon listening rooms,
we are fortunate to possess a
unique library of more than
1,000 original master tapes of
recordings made during the
Golden Age of studio engineer­ing from 1956-1976.

Unlike conventional commercial
releases, our master tapes cap­ture the dynamic contrasts and
subtle inner harmonic structure
of the musical event, forcing us
to work to a higher standard in
our efforts to maintain the integri­ty of the original musical per­formance.

Design Principles

With state of the art technical
equipment and some of the
finest minds in the audio engi­neering field at our disposal, the
Gryphon brand name continues
to define the highest audiophile
standards of subjective and
technical performance.
The dual mono configuration
radically eliminates any possibil­ity of crosstalk or other interfer­ence between channels and pro­vides infinite channel separation
which contributes to the ability to
create space, focus, depth and
transparency.

Because the electrical power
coming out of your wall fluctu­ates wildly in terms of voltage
and distortion, Gryphon incorpo­rates heavily regulated multi­stage power supplies that act as
effective mains conditioning fil­ters. Displays and control circuits
are fed by a separate power sup­ply to isolate any digital noise
artifacts and effectively prevent
them from contaminating the sig­nal path.

While the printed circuit boards
in more conventional audio prod­ucts utilize conductor tracks a
mere 35 micron thick, Gryphon
employs at least 70 micron
traces of the highest purity.

Gryphon is located in beautiful tranquil sur­roundings.

5

Beginning with our very first
product, “The Head Amp” all
Gryphon products have featured
extremely wide frequency band­width, because the ability to
reproduce ultra-sonic frequen­cies with no difficulty ensures lin­ear phase across the audible fre­quency range.

The implementation of circuits
with wideband frequency
response is a painstaking
endeavor in which the actual lay­out and ground pattern of the PC
boards are crucial to the
achievement of superior sonic
performance with no loss of
inherent stability.

Wideband frequency response
ensures the high slew rate
essential to the realistic handling
of the ultra-fast transients which
routinely occur in live music and
is crucial in recreating the natu­ral decay of musical instruments.
Wide bandwidth also improves
phase characteristics, for more
correct soundstaging and imag­ing.

All Gryphon designs are realized
with an absolute minimum of
negative feedback, which when
present in large amounts can
actually increase TIM distortion.
All Gryphon preamplifiers are
designed with zero negative
feedback. Gryphon power ampli-

fiers apply zero or minimum neg­ative feedback judiciously for
improved linearity and band­width.

Gryphon research into the detri­mental effects of magnetically
induced distortion (MID) has led
to the elimination of magnetiz­able materials wherever possi­ble. To eliminate the effects of
stray magnetic fields, non-mag­netic materials are employed
throughout, with the unavoidable
exception of the transformer
shield box.

The mechanical design of the
cabinet and assembly methods
are all carefully calculated to
ensure minimal resonance,
either through the use of
mechanically grounded high
mass or decoupling. Vibration­sensitive components, capaci­tors in particular, are thus guar­anteed a non-resonant environ­ment.

The heavy, thick chassis offers a
vibration-proof environment for
the sensitive electronics inside
and provides crucial shielding
from a polluted world of low and
high-frequency radio waves,
power-line radiation and other
electrical interference.
Meticulous attention to such
issues makes a significant con­tribution to the relaxing, open

Typical Gryphon module

6

and transparent Gryphon sound.
Unique, non-invasive protection
circuitry offers reliable, fuss-free
protection without compromising
signal purity and signal path sim­plicity, with no conventional
relays in the signal path to
degrade or compress sound.

The ground path has been care­fully laid out in order to achieve
superior sonic performance with
no loss of stability. Component
layout has been designed to
ensure the shortest conceivable
signal path.

Exhaustive investigation under­lies the selection of every com­ponent part and many original,
proprietary components are cus­tom-built exclusively for
Gryphon. Because what is left
out is just as important as what
goes in, an absolute minimum of
internal wiring is included.

By lavishing attention on each
aspect of the circuit and fully
understanding the purpose and
behavior of every single part of
the whole, our designers can
optimize performance in each
section, before moving on to the
next step. This ensures simplici­ty, a short signal path and a unity
of purpose with a single, well­defined objective: musical purity.

In the interest of ultimate fidelity,

tone controls, balance controls
and other unnecessary compo­nents have been banished from
the signal path.

Exterior Design

From the very beginning, every
Gryphon product has offered
stunning audio performance,
sumptuous styling and superb
user-friendliness, catering to the
needs of the discerning audio­phile who demands musicality,
convenience and aesthetics, all
without compromise.

In every Gryphon product, form
follows function in a unique syn­thesis of aesthetics and practi­cality. Gryphon stands for
sophisticated technology with a
high standard of industrial finish
that also incorporates the best of
handcraftsmanship.

The peerless finish, build quality,
ergonomics and pride of owner­ship that contribute to the totality
of the Gryphon concept can only
be fully understood and appreci­ated up close and in person.

Rasmussen’s background in fine
arts and industrial design gives
every Gryphon product a distinc­tive, luxuriant finish which arises
organically out of the audio cir­cuit design and the user inter­face for a truly unique integration

of form and function.

Gryphon Audio Designs in the
outskirts of the small town of Ry

7

Manufacture and
Assembly

At our laboratories and manufac­turing facilities in Denmark, we
maintain full control over every
aspect of development and pro­duction, and the members of our
conscientious staff diligently fol­low each Gryphon model from
initial concept to early prototype,
through to final quality control.

Printed circuit boards are
assembled by a supplier of pre­cision military and medical
equipment with strict standards
of quality control and pre-inspec­tion of components. Chassis
parts are manufactured by a
specialist chosen solely for the
outstanding quality of workman­ship. In every aspect of every
Gryphon product, the same
stringent standards of excel­lence apply.

Following a 48-hour burn-in,
each product is tested again,
before being subjected to
Gryphon’s custom-developed
transport simulator which simu­lates the inevitable shaking that
a product will encounter in tran­sit. The product is placed on top
of a very large loudspeaker
which plays a special CD with
low frequencies which simulate
the vibrations of an airplane.
Each unit “travels” the equivalent

of 40 round trips from Denmark
to Australia before leaving the
factory.

AC Voltage

Your Gryphon unit is especially
made for the AC voltage of the
country to which it has been
shipped.

If the voltage has been
changed, the warranty is void
and the product may be unsafe
or malfunction.

Correct AC polarity contributes
greatly to optimum performance.
If you are not using a three-pin,
non-reversible power plug,
please experiment with the ori­entation of the plug for optimum
performance.

Burn-In and Warm­Up

Your Gryphon unit has been
thoroughly tested and burned in
before shipping. Performance
will continue to improve during
the first 40 – 50 hours of normal
use. After this period optimum
performance will be reached
approximately 45 minutes after
turn-on. With the exception of
Class A power amplifiers, we
recommend leaving your
Gryphon components powered

up at all times.

8

Balanced
Connections

All Gryphon products use the
AES standard for balanced con­nections.

1. Ground

2. Positive

3. Negative
We recommend the use of dedi­cated balanced cables. Avoid the
use of adaptors as they degrade
performance.

Choice of Cables

Because your Mephisto is a
high-resolution Gryphon audio
device, it will immediately reveal
the characteristics and possible
limitations of the other compo­nents in your system, as well as
those of the interconnects and
loudspeaker cables used to con­nect your system.
Wiring should never be utilized
as "equalizers" to correct errors
elsewhere in the system.
Instead, any error should be cor­rected at the source, so that
interconnects and loudspeaker
cables can be selected solely on
the basis of sonic neutrality. For
this reason, we employ
Gryphon's own range of inter­connects and cables in every
stage of the design of every
Gryphon product.

Care and
Maintenance

Gryphon products are handcraft­ed by individuals who take great
pride in the high level of fit and
finish which we achieve. To
maintain your Gryphon compo­nents in pristine condition,
please follow these simple
instructions.

Metal surfaces may be cleaned
with a damp cloth. Some product
made for treatment of vinyl inte­riors in cars may be useful. Test
the product on a non-visible sur­face, before using any fluids.

Acrylic surfaces should only be
wiped with a very soft, dry cloth.
Small scratches may be
removed with fiberglass polish.
Fingerprints may be removed
with a damp cloth. Do NOT use
spirits or paper tissue.

9

The Gryphon
Mephisto

User Guide & Introduction

Features:

Fully balanced inputs
200 Watts per channel Pure
Class A
40 High current bipolar output
transistors pr. channel
500,000 µF power capacitor
bank per channel
Flat frequency response to
beyond 350 kHz
Zero negative feedback
No output relays
User-programmable Green
Class A bias
DC servo coupling
Frequency-independent damp­ing factor
Rigid mechanical structure
Microprocessor controlled,
non-invasive “smart” protection
system
Upgradeable software.
Double sealed, mil spec PCB
with 105 µm copper traces.

Sonic excellence

The Mephisto impresses imme­diately with its ability to cruise
effortlessly through even the
most demanding musical pas­sages, regardless of volume
level. As a result of the constant
high power reserves available at
all times, the amplifier simply
does not "see" the speaker, so
the speaker's reactive load can­not degrade amplifier perform­ance. Unlike other high power
amplifiers, Gryphon's no com­promise pure Class A topology
allows the Mephisto to offer high
power as well as refinement and
delicacy in musical presenta­sion. It is our fundamental phi­losophy that all electronics in the
playback chain must ideally be
neutral and not add or subtract
anything from the recording no
matter how "attractive" such dis­tortions may be. The Mephisto is
by nature a product for the fortu­nate few who can afford such a
statement, just as it is a product
for the increasing number of
audiophiles who seek purity in
the reproduction of music, a
product for the music lover who
respects both the musicians and
recording engineers enough to
refrain from adding or subtract­ing anything in relation to the
original intention of the record­ing.

10

Circuit Topology

Power is the name of the game
and the Mephisto is equipped to
take on even the most vicius and
nightmarish of speaker loads.
The output section uses Sanken
bipolar output devices which
have demonstrated extreme reli­ability in addition to outstanding
sonic performance. These tran­sistors can be called upon to
deliver momentary peak power
of 4,000 watts per channel with­out overload. Each of the 40
transistors is bypassed with indi­vidual film capacitors. The sepa­rate driver section has its own
supply from individual windings
on the custom-made toroidal
transformers. Unique mechani­cal design ensures optimal ther­mal tracking between drivers
and output devices. The driver
section features its own gener­ous bank of 50.000 uF of ultra­fast capacitance.
The power capacitor bank is an
astounding 500,000 uF array of
capacitors.
No negative feedback is
employed and DC coupling
employs DC servo circuitry.
Internal wiring in the signal path
is kept to an absolute minimum.
The input wiring is Gryphon
Guideline Reference gold­embedded silver cable. Only bal­anced inputs are provided.
Unique even in this price range,

The Gryphon Mephisto utilizes a
completely independent trans­former and power supply for
control circuits, effectively pre­venting digital noise generated
by these circuits from reaching
the amplifier circuits.
Gryphon proprietary speaker ter­minals accept bare wire, spade
lugs, banana connectors or any
combination.

Class A

True Class A operation has
always been a Gryphon bench­mark, simply because nothing in
our experience can match the
sonic glories of pure Class A.
Unfortunately, true Class A is
even rarer today than when we
introduced the DM100. Rising
consumer awareness has forced
some manufacturers to stop
making outrageous unsubstanti­ated claims of Class A power rat­ings that only exist in the fevered
imagination of some marketing
"expert".
Still, there is a growing number
of so-called "new" Class A
topologies based on automatic
biasing which, simply explained,
somehow allow the amplifier to
sense when the bias should
increase to ensure constant
Class A performance!
If such thing were to actually
work as claimed, it would be tan­tamount to a re-writing of the
laws of physics. In order for an

11

amplifier to be able to increase
bias and stabilize thermally to
instantaneously track the
dynamics of the input, it would
have to be able to predict what is
going to happen next on the
recording. Auto-biasing can by
nature only respond to some­thing that has already happened
and the bias will rush up and
down in a desperate attempt to
follow the last note.
Put bluntly, there is no such thing
as a free lunch when it comes to
pure Class A, so we repeat with
no apologies: TRUE PURE
CLASS A means heavy trans­formers, very large heatsinks,
lots of heat, lots of electricity,
expensive parts and costly
assembly.
While we appreciate and
endorse every effort to conserve
energy and preserve our global
resources, our research into
efforts to obtain Class A perform­ance from class A/B topologies
makes it clear that there simply
is no substitute for the sheer
magic of pure class A.
However, based on thorough
analysis of typical listening situa­tions, we have devised Green
bias (green for reduced environ­mental impact). Green bias
offers TRUE, PURE CLASS A
with considerably lower power
consumption than the traditional
solution.
With the DM100, Gryphon was

the first amplifier manufacturer
ever to offer programmable
Class A bias as a means of
reducing power consumption
without compromising Class A
performance.
Green bias in the Gryphon
Mephisto allows the user to
select the amount of Class A at
any given time, taking into
account such factors as speaker
sensitivity, room size , musical
dynamics and overall volume
level.
Green bias improves on our pro­grammable bias by giving the
fortunate owners of a Gryphon
preamplifier the option of letting
the preamplifier automatically
control the bias.
Instead of a conventional poten­tiometer, the Gryphon Pandora
Preamplifier employs a 85 positi­ion volume attenuator which can
be used to select the bias to
match the overall playback level,
thus ensuring pure Class A at all
times.
Unlike signal-sensing "auto-bias­ing systems" Green bias does
not attempt to follow the signal at
all, the current position of the
volume control determines the
bias setting whether music is
playing or not. In effect, this
means that if the user selects,
for instance, position 46 (
Pandora ) on the volume con­trol, then the bias will increase to
100% (High Bias) producing 200

12

tional relays in the signal path to
degrade or compress sound.
When DC or HF is detected at
the input, the amplifier powers
down until the error condition is
corrected.
The output signal is constantly
compared to the input, so that, in
the presence of a difference
which exceeds predetermined
limits (typically a short circuit
condition), the amplifier mutes
until the error condition has been
corrected. Heatsink temperature
is constantly monitored by a
thermistor. In the event of over­heating (temperature in excess
of 80° C), the amplifier will
power down and normal opera­tion can resume when a safe
operating temperature is
reached.

Exterior

Non-magnetic materials are
employed throughout, the only
exception being the mechanical­ly isolated transformer housing
The faceplate is machined from
a solid 40 mm black acrylic
block. A LED display provides
continuous information on Class
A status and AC condition.
With the exception of the face­plate, the Mephisto exterior con­sists entirely of brushed, black
anodized alluminium.

13

Watts pure Class A. This bias
level will be maintained even
when music is absent or when
the amplifier or preamp is muted.
If the user turns the volume con­trol down below position 45, the
Preamplifier will automatically
instruct the amplifier to reduce
bias to 50 watts of pure Class A.
Bias L is selected manually from
the front panel. To leave L bias
you must select M or L bias on
the front panel.
If Green bias is activated,

GB

will be lit for 5 sec. in the dispaly
and the amplifier will automati­cally adjus bias to match the
postion of the preamp volume
control.
While Green bias does not offer
the extreme low power con­sumption of Class A/B, or even
the low power consumption of
"auto-biasing" systems, it does
offer significantly lower power
consumption without sacrifice or
compromise of even a fraction of
its PURE CLASS A performance.
The Mephisto user who do not
own a Gryphon preamplifier can
access the programmable bias
system manually.

Protection

The unique, non-invasive protec­tion system offers reliable, fuss­free protection without compro­mising signal purity and signal
path simplicity, with no conven-

Installation

Unpacking

Obviously, the purpose of pack­ing materials in the transporta­tion of heavy amplifiers is to pro­tect the product on its perilous
journey from manufacturer to
proud owner.
Unfortunately, in our experience
this often results in sprained
backs and bleeding fingers at
the moment of truth: the uncrat­ing og the beast.
The mephisto comes in a dedi­cated flightcase offering excel­lent protection - keep this for
eventual future use. Do not try to
lift it out without help,. do not lift
with you back but bend your
knees and lift with your legs. Do
not at any time let the amplifier
rest on its faceplate, but always
on its feet.
Enclosed i box is:
1 Mephisto
2 Pair of gloves
1 Acrylic polish
2 AC power cords
1 Warranty card
1 green bias cable

If anything is missing or dam­aged, please contact your

Gryphon dealer immediately

AC Power

VERY IMPORTANT

Before installation, you must
ensure that sufficient current is
available from you domestic AC
power supply:

Minimum: 10A for 220/240 V
Minimum: 20A for 100/120 V
It is also very important that the
wiring from your AC breaker can
carry the high constant AC volt­age with only a minimum of loss.
A conductor with a minimum
gauge of 1.5 sq. mm. is recom­mended.
The Mephisto should ideally be
connected to a separate AC
breaker group independent of
other equipment.

Placement

The Mephisto is a high bias
Class A design and MUST be
placed so that air may circulate
freely around the heatsinks. The
Mephisto is equipped with tall
feet for free air circulation, even
on thick carpets. The feet also
allow you to push the amplifier
across the floor without lifting it.

14

AC Fuses

Mephisto Fuseholder:
220-240v. 8 AT
100-120v. 15 AT

AC Power Cords

Use only a dedicated AC power
cord. Do NOT use loudspeaker
cable or other wire not expressly
designed to carry high current.
Improper cable or cables of
insufficient gauge will generate
heat and the insulation may melt
with disastrous results.
AC cords DO have an audible
effect on sound quality, but
experiments should be carried
out with due consideration to
safety.

Power Line
Conditioners?

We do not recomend the use of
any kind of power line condition­ing with the Mephisto
If you wish to experiment with
external line conditioners or
other devices, we strongly rec­ommend that you listen to the
Mephisto without these devices
before making your decision.
Remember to listen for correct
sound and not merely different
sound.

15

AC Polarity

Do not run, thin, coiled, exten­sion cords.
The Mephisto is a true dual
mono construction and we must
stongly emphasize the impor­tance of symmetrical AC power
polarity for each channel.
Asymmetrical AC polarity will
seriously degrade soundstage
recreation and other important
aspects of the Mephisto per­formance.

Front panel functions

From left:

1.ON/STB
Turns off all active circuitry, but
there is still AC power inside the
Amplifier. For full shutdown use
the 2 master AC power switches
on rear or disconnect the AC
cords.
When turning the Mephisto on
from the front, the Gryphon logo
and all display indications will
flash for approx 15 sec. before
the amplifier is fully operational.
When the amplifier is ready the
Gryphon logo will stay on and 2
green

OK indicators will be on

for 15 sec. If Green bias cable is
connected, Green bias (GB)
light will also be on for 15 sec.

Fuses - fuse holder
placed just below display
at front behind small
heatsink. Can be acessed
from front.

16

2. MUTE
Use this function when changing
speaker cables or interconnects
without turning the amplifier off.

3.

CHECK This function allows

you to check that all indicators
are operational.
The bias selector determines the
degree of Class A operation. In
the 100% mode the Mephisto
provides 200 watts of PURE
CLASS A power into an 8 ohm
load. The bias adjustments do
not change total output power,
but only the Class A operation
range.
With very efficient speakers, 200
Watts of pure Class A might
rightly be considered overkill.
With LOW BIAS, efficient speak­ers will be driven in Class A
most of the time.
Naturally, lowering the Class A
operation reduces powercon­sumption and heat dissipation at
idle...

4.Low bias
Use to keep circuitry in amplifier
ready for listening without initial
warm-up. If left in inactive in L
bias for longer periods, use the
mute function, too.

5.

Medium Bias Can only be

used when the Automatic Green
bias is disabled. This position
provides 50 Watts of pure class
A, more than enough for normal

listening conditions and speak­ers with normal sensitivity. In this
setting 175 watts of Class A/B
power is available.

6.

High Bias - 100% Class A

power for the ultimate perform­ance.

Choosing bias setting

When evaluating the sonic effect
of the 3 bias adjustment modes,
it must be taken into considera­tion that the Mephisto requires
time to settle when bias is
changed. (15 min.)
Bias may be adjusted with the
Mephisto turned on. However,
we recommende that bias
adjustment be made once and
for all during initial installation.
If the Mephisto has been turned
off using the front panel on/off
switch, it will remember the last

bias setting. After using the
master on/off switch at the rear
panel, it will return to its last set­ting.

Green Bias

If you own a Gryphon preampli­fier with the green bias link, The
Mephisto will automatically
change bias with reference to
the current position of the
Preamplifier´s volume control,
independent of the music signal.
If you wish the Mephisto to go to

Bias setting has no effect
on overall power that
remains unchanged,. the
bias is only changing the
portion of the power that
runs in Class A

L bias for idling, you must use
the stand-by switch on the front
panel. Remember, the Green
bias system is not in the signal
path and has only reference to
the preamplifiers microprocess
that is entirely outside the signal­path.
The Mephisto responds to pre­programmed switching points at
the volume control, based on our
experience with most speakers.
It is however, possible to lower
the switching positions if you
have efficient speakers or if you
wish to play at 100% Class A
even at low playback levels.
Please refer to the preamplifier´s
manual for further information
about this.
If you remove the link between
the Mephisto and the preamplifi­er, the amplifier will automatical­ly revert to manual operation
only.

Rear Panel Functions

Speaker terminals
The binding posts are custom
designed by Gryphon. The spe­cial design will provide a tight
reliable connection to: plugs,
lugs or bare wire. Do not use
tools or excessive force when
tightening the terminals.

Link in is automatic switching
the Mephisto on when connect-

ed to a unit with same feature
and protocol.
Link out is automatic switching
other units on from the Mephisto

Balanced Input.

The Mephisto provides only bal­anced input. There are no deteri­orating phono sockets in parallel
with the balanced input.

The Mephisto balanced inputs
are made to AES standards:
Pin # 1 Shield
Pin # 2 Positive
Pin # 3 Negative

BIAS
Connection for Green bias link
between compatible Gryphon
preamplifier´s and the Mephisto

The Mephisto
protection System

Gryphon has designed a unique
comprehensive system with no
circuit breakers in the signal
path. The “smart” Gryphon pro­tection system constantly moni­tors the amplifier by checking 10
times per sec. when the amplifi­er is on.
DC & HF:
When DC or HF from the source
component is detected, or du to
an internal problem, the

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checking the amplifier 10
times every second

Mephisto will power down imme­diately: Normal operation can
resume when the error condition
is corrected.

OVERHEATING:
When excessive heat is detect­ed, the thermal sensor will react
and the amplifier will go in stand­by mode. Normal operation can
resume when the temperature is
within safe operating limits.

SHORT CIRCUIT:
Special care should be taken at
all times to avoid shorting the
loudspeaker outputs. If a short
circuit should occur, the
Mephisto will power down.

We are aware that the Mephisto
is the choice of the very experi­enced audiophile, so please
bear with us while we repeat cer­tain ground rules:

TURN-ON PROCEDURE:

1. Turn on source components,
Turntable, CD Player, etc.)

2. Turn on preamplifier

3. Allow a few moments for com­ponents to stabilize, (tube equip­ment may require more time).

4. Turn on power amplifier

TURN-OFF PROCEDURE:

1. Turn off power amplifiers.

2. Turn off rest of the system.
PLEASE
ALWAYS TURN OFF OR MUTE
THE POWER AMPLIFIER
BEFORE CONNECTING OR
DISCONNECTING ANY
CABLES IN THE SYSTEM.

INTERNAL FUSES

ON faceplate below display ­under small heatsink.

From left
Fuse # 1 63 mAT
Fuse # 2 63m AT
Fuse # 3 1 A T
Fuse # 4 1.6 A T

Fuses 1-4 are all for the supply
of digital circuits.

Main AC fuse is located on the
back plate.

Replace only with same value
fuses.

WARNING

Do not remove cover of amplifier
unless AC cords are removed
from amplifier.

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TROUBLE­SHOOTING

No Light in on/stb indicator

*Check both AC cords
*Check both on/off switches on
rear panel
*Check your domestic AC supply
*Check AC fuses on rear panel
*Check fuses on front

On/Stb is on but amplifier

will not start up.

*Check error indicators on dis­play
*Check both powercords and
fuses.

Error L or Error R indica­tor is flashing.

Amplifier has powered down due
to a DC or RF error. Correct
problem ( check connected
equipment ) and power the
amplifier up again.

AC error indicator are flash-

ing.

AC power is not meeting
amplifiers minimum require­ment.

*Available AC power is too low.
Minimum requirement is:
100 - 120v. countries : 95 v.
200 - 240v. countries : 190 v.

Temp. L indicator are flash-

ing:

Left channel is overheating.
secure air circulation around the
unit. Start amplifier again after 5
min.

Temp R. indicators are flash-

ing:

Right channel is overheating.
See above.

Tweak Alert

In the best Gryphon tradition we
have spent a huge amount of
time with our prototypes before
we release a new product. We
are obsessed with what we do
and consider ourselves to be
open-minded and are fascinated
by the "Grey area" between logi­cal, technical facts and things we
just hear that make no obvious
technical sense.We will imple­ment them as long as it does not
sacrifice safety or reliability. In
the Mephisto design a number of
tweaks can be found and the
result is a fine balance that can
easily be disturbed.
We strongly advise against any
alteration of the original design,
it will void the warranty and most
certainly only provide a diffence,
not a real improvement of musi­cal realism.
We are fully aware of the fun of
playing with AC conditioners,
bricks, platforms, cables and so
on. We appreciate much of it,

19

If you need support you must contact
the dealer where you purchased the
unit.
Requests for support directed to our
service department will be forwarded to
your dealer.
We can not offer direct support.

but please listen to our intentions
before you go ahead and if you
do, do yourself (and us) the favor
of now and then going back and
listening to the "naked" design
as it was intended.

Enjoy…

Warranty

The Mephisto is warranted
against failures arising through
faulty workmanship and materi­als for a period of 2 years from
date of purchase. The warranty
is not transferable.

This warranty
is only valid in the country where
the product was purchased

. All
claims under this warranty must
be made to the distributor in the
buyer

`

s country by returning the
unit securely packed in the origi­nal box with all accessories,
postage/freight prepaid and
insured. The unit will be repaired
or replaced at no charge for
parts and labor.

This warranty remains valid only
if the serial number of the unit
has not been defaced or
removed and if repairs are per­formed only by authorized
Gryphon dealers or distributors.

It does not cover damage due to
misuse, accident or neglect. This
warranty is not valid if the oper­ation voltage of the product has
been changed. The distributor or

manufacturer, Gryphon Audio
Designs, Denmark, retains the
exclusive right to make such
judgement on the basis of
inspection.
The retailer, distributor or manu­facturer of the Gryphon shall not
be liable for consequential dam­age arising from the use, misuse
or failure of this product, includ­ing injuries to persons or proper­ty.

To qualify, the enclosed warranty
registration card must be filled
out and returned to the manufac­turer within 10 days of purchase.

Alternatively, you may choose to
register your Gryphon on our
website:

www.gryphon-audio.com

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