Einstein The Light in the Dark User manual

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Dear EINSTEIN customer!
With the EINSTEIN The Light in the Dark stereo amplifier, you have acquired that rarest of Hifi components
— one that conforms to the most stringent standards of electrical design and mechanical integrity. To get
the most from it, please take a few leisurely moments and peruse the following instructions.
The Light in the Dark is a component that deliberately eschews frilly features to focus instead on the core
essentials:
•Realistic reproduction with the utmost fidelity
•Rock-solid reliability for years of worry-free service
•Intuitive user interface everyone in your household can use
•Extended market value to protect your investment
The EINSTEIN The Light in the Dark does not sound beautiful, soft or energetic. Our goal is to design com-
ponents that integrate into existing systems with the absolute minimum of signal degradation or “artistic
license“. A stereo amplifier’s job is simple (though by no means easy): increase signal amplitude; pass
this amplified signal to the loudspeaker; take control of the transducers. Even the “world’s best“ loud-
speaker cannot correct for losses or errors incurred by the amplifier. Quite the contrary. A superior loud-
speaker will ruthlessly reveal any shortcomings in the amplifier driving it. Hence your decision to incorpo-
rate the EINSTEIN The Light in the Dark into your system was a truly informed one. Congratulations.
We extend our regards from Bochum and wish you much musical satisfaction from your new EINSTEIN
The Light in the Dark.
Volker Bohlmeier

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1. Safety concerns - what not to do
•Don’t pry inside the machine. It uses high voltages. You’ll void the warranty and risk electric
shock.
•For safety reasons especially with pets and children, use the tube cage.
•Protect the machine against moisture and condensation.
•Don’t defeat the ground.
•Only replace fuses with original type ((1.25A fast-blow for 230-240V Version; 2.5A fast-blow for
115- 125V Version)
•When tube replacements are due, please contact your dealer or our factory.
2. What your shipping carton contains
•1 x EINSTEIN The Light in the Dark stereo amplifier inside a velour-covered wooden crate
•1 x power cord
•1 x ground wire
•2 x gloves for handling
•1 x owner’s manual
•1 x warranty card
3. Design overview
The Light in the Dark closely mirrors the circuitry of our celebrated The Final Cut OTL mono amplifiers. In
fact, without their precedent, the stereo amp in its current version would have never seen the light of day.
The OTLs paved the way for the unique and proprietary realization of the stereo amplifier’s circuit architec-
ture. To not bore you with tech talk, let’s put it this way: The Light in the Dark is the The Final Cut, albeit
with transistors rather than valves in the output stage.
4. Setup
Insure adequate ventilation and a solid hard foundation. Do not place The Light in the Dark atop other
components nor place other components atop the EINSTEIN amplifier. Due to the enormous capacities of
our overbuilt transformers, record players and phono stages should not be placed in close proximity to
avoid picking up hum. Proper HiFi racks with adequate spacing are most suitable and can even improve
audible system performance.

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5. AC mains connection
The IEC power inlet and mains fuse holder are located on the left side toward the front and on the belly of
the machine. Disconnect the amplifier from the AC plug if you have to replace the fuse. Internal rail volt-
ages of 230 volts can cause serious electric shock.
6. Component connections
Before initial power-up, install the interconnects to the preamplifier and the cables to your loudspeakers. If
possible, connect the included ground wire between the grounding posts of your preamp and amplifier.
Interconnects
Use any high-quality RCA or XLR-terminated cable. Insure good non-oxidized contacts. Naturally, we rec-
ommend our own NF/XLR cable which has been designed for optimum synergy. Because The Light in the
Dark operates fully differential from input to output, XLR connections from the preamp are the preferred
means for optimal results, especially when that preamp happens to be our fully differential, fully balanced
(and fully complementary) The Tube valved linestage!
Loudspeaker cables
Insist on cables with superior non-oxidized contacts and sufficient conductor mass to supply adequate cur-
rent to the speakers. This insures proper damping factor for mandatory transducer control. (Cables of in-
sufficient conductor mass can strangulate an amplifier’s current delivery.)
7. Power mains
To turn the machine on or off, rotate the left frontal control. Three blue LEDs inside the central display will
confirm power as will the glow of the valves. Thermal stabilization and final readiness are indicated after
about 2-3 minutes once the two outer LEDs have extinguished. Should one or both of these outer indica-
tors remain lit, contact your dealer or the factory to avoid internal damage. Optimal operation conditions
and stabilized sonics for The Light in the Dark are reached within a half hour of turn-on.
If there is a problem with the amplifier, either both or one or the other LED will remain lit, at which point
you should turn the amplifier off and contact your dealer / distributor or EINSTEIN directly. The unit will
achieve its optimal sound and operating temperature after approximately half an hour. It is recommended
that you don’t tax the amplifiers unnecessarily during this warm up phase as it may result in lower tube
life.

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8. Control from front face plate
The two front panel mounted switches control the following functions of the amplifier: left switch — on /
off; right switch — standby
9. Fittings on the back
Here you find the loudspeaker binding posts (red/right channel, white/left channel) and the low-level in-
puts (red/right and white/left). Although The Light in the Dark is optimized for fully balanced operation,
the machine will accept single-ended connections from non-balanced preamplifiers. RCAs marked red are
for non-inverting operation, white RCAs invert polarity should your preamplifier invert phase. The single-
ended inputs connect directly to the XLRs (1 ground, 2 plus, 3 minus). This supports bi-amp or subwoofer
connections when you run the amplifier with balanced inputs. Simply use the single-ended connections as
outputs. If The Light in the Dark connects to your preamp via RCAs (either regular or inverted), cap the
two unused single-ended inputs with the provided shorting plugs.
The input level control allows signal matching with your preamplifier to maximize its useful volume control
range. In bi-amp mode, the input level control matches outputs between two amplifiers. Be sure to not
close this attenuator fully counter-clockwise or The Light in the Dark won’t output any sound.
10. Fuses
A blown fuse could indicate internal problems. Should the amplifier refuse to operate after a blown fuse
has been replaced, please contact your dealer or EINSTEIN immediately. A proper replacement fuse must
be marked 1.25A fast-blow for 230-240V version; 2.5A fast-blow for 115- 125V version.
Before replacing a fuse, insure that the amplifier is disconnected from your wall outlet to avoid risk of
electric shock. Both mains fuses are housed adjacent to the IEC power inlet at the bottom of the machine.
11. Valves
The Light in the Dark uses E88CC tubes with a life expectancy of about 2000 hours. To assure optimum
performance, only use tubes your EINSTEIN dealer supplies. We take pains to properly inspect and test all
EINSTEIN tubes for years of trouble-free and uncompromised performance.
12. Service
Should you encounter any problems, please contact your dealer, your distributor or EINSTEIN directly.
13. Cleaning
Use a soft cloth and glass cleaner to polish the chrome and stainless steel parts.

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14. Performance Tips
You may enjoy improved performance if you pay attention to the following: Correct AC power phase; high-
quality low-impedance interconnects between preamp and amp; proper AC mains filtration or conditioning;
suitable performance power cord; resonance control by way of a well-engineered equipment support;
proper system grounding via a single earth ground; high-quality loudspeaker cables.
15. Warranty
The EINSTEIN The Light in the Dark carries a 3-year parts & labour non-transferable warranty (6 months
for tubes) if the following conditions are met:
We have received your warranty registration card within 14 days of purchase (validated by stamp or sig-
nature of an authorized dealer) as accompanied by a copy of your sales receipt
No unauthorized modifications or service have been performed.
Service appointments during the warranty period must be dispatched in their original packing materials.
Should your amplifier be returned to EINSTEIN for service (or an authorized service center), the remainder
of the warranty period remains intact.
TheService Check at EINSTEIN includes the replacement of the four input tubes; a complete bench test
with printed-out checklist; 12-hour non-stop operation; and a subsequent listening test.
16. Technical Specifications
•S/N ratio: > 96dB
•Channel separation: > 80dB
•THD @ 1kHz: < 0.02%
•Power output: 80 watts/8 ohms (115 watts/4 ohms)
•Damping factor: > 250/8 ohm
•Weight: 44 lbs
•Dimensions: 16.9“ x 15.4“ x 6.7“ (W x D x H)
17. Final test prior to shipping
•Sighted inspection O.K. Tester
•Electric test O.K. Tester
•Listening test O.K. Tester
•Packing/contents O.K. Tester