Einstein The Light in the Dark User manual

AUDIO ELEKRONIK BOHLMEIER
PRINZ REGENT STR. 50 60
D 44795 BOCHUM
TELEFON [phone]
TELEFAX 0049 (0)234 9731511
SPARKASSE BOCHUM
BANK CODE 43 050 001
ACCOUNT No 5 401 070
www.einstein-audio.de
IBAN: DE26 4305 0001 0005 4010 70 SWIFT: BICWELADED1BOC
StNr.: 350/5024/0706 UstId: DE811577342
Dear customer!
With Einstein’s “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
Einstein’s “The Light in the Dark“ does not sound beautiful, soft or
energetic. Our goal is to design components 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“ loudspeaker cannot correct for losses or errors
incurred by the amplifier. Quite the contrary. A superior loudspeaker
will ruthlessly reveal any shortcomings in the amplifier driving it.
Hence your decision to incorporate Einstein’s “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

AUDIO ELEKRONIK BOHLMEIER
PRINZ REGENT STR. 50 60
D 44795 BOCHUM
TELEFON [phone]
TELEFAX 0049 (0)234 9731511
SPARKASSE BOCHUM
BANK CODE 43 050 001
ACCOUNT No 5 401 070
www.einstein-audio.de
IBAN: DE26 4305 0001 0005 4010 70 SWIFT: BICWELADED1BOC
StNr.: 350/5024/0706 UstId: DE811577342
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 flint = slow-blow/ceramic?)
•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 velours-
covered wooden crate and draw-string cloth pouch
•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 monoblocks. 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 architecture. 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.

AUDIO ELEKRONIK BOHLMEIER
PRINZ REGENT STR. 50 60
D 44795 BOCHUM
TELEFON [phone]
TELEFAX 0049 (0)234 9731511
SPARKASSE BOCHUM
BANK CODE 43 050 001
ACCOUNT No 5 401 070
www.einstein-audio.de
IBAN: DE26 4305 0001 0005 4010 70 SWIFT: BICWELADED1BOC
StNr.: 350/5024/0706 UstId: DE811577342
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.
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
voltages 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 recommend our own
NF/XLR cable which has been designed for optimum synergy. But that’s
just our opinion... 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 current to the
speakers. This insures proper damping factor for mandatory transducer
control. (Cables of insufficient conductor mass can strangulate an
amplifier’s current delivery.)

AUDIO ELEKRONIK BOHLMEIER
PRINZ REGENT STR. 50 60
D 44795 BOCHUM
TELEFON [phone]
TELEFAX 0049 (0)234 9731511
SPARKASSE BOCHUM
BANK CODE 43 050 001
ACCOUNT No 5 401 070
www.einstein-audio.de
IBAN: DE26 4305 0001 0005 4010 70 SWIFT: BICWELADED1BOC
StNr.: 350/5024/0706 UstId: DE811577342
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 indicators 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.
8. Further controls on the front.
•The right rotary control engages mute.
.
9. Fittings on the back.
•Here you find the loudspeaker binding posts (red/right channel, white/left
channel) and the low-level inputs (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.
+

AUDIO ELEKRONIK BOHLMEIER
PRINZ REGENT STR. 50 60
D 44795 BOCHUM
TELEFON [phone]
TELEFAX 0049 (0)234 9731511
SPARKASSE BOCHUM
BANK CODE 43 050 001
ACCOUNT No 5 401 070
www.einstein-audio.de
IBAN: DE26 4305 0001 0005 4010 70 SWIFT: BICWELADED1BOC
StNr.: 350/5024/0706 UstId: DE811577342
10. Fuses
•A blown fuse could indicate internal problems. Should the amplifier refuse to
operate after a blown fuse has been replaced, contact your dealer or our
factory. A proper replacement fuse must be marked 1.25A slow-
blow/ceramic?. 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
3000 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 or our
factory.
13. Cleaning
•Use a soft cloth and glass cleaner to polish the chrome and stainless steel
parts.
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.

AUDIO ELEKRONIK BOHLMEIER
PRINZ REGENT STR. 50 60
D 44795 BOCHUM
TELEFON [phone]
TELEFAX 0049 (0)234 9731511
SPARKASSE BOCHUM
BANK CODE 43 050 001
ACCOUNT No 5 401 070
www.einstein-audio.de
IBAN: DE26 4305 0001 0005 4010 70 SWIFT: BICWELADED1BOC
StNr.: 350/5024/0706 UstId: DE811577342
15. Warranty
•Einstein’s “The Light in the Dark“ carries a 3-year parts & labor 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 signature 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 Audio Elektronik for service (or an authorized service
center), the remainder of the warranty period remains intact. Our Service
Check in Bochum 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. This service is currently invoiced at 250
Euro.
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
•Packaging/contents O.K. Tester

AUDIO ELEKRONIK BOHLMEIER
PRINZ REGENT STR. 50 60
D 44795 BOCHUM
TELEFON [phone]
TELEFAX 0049 (0)234 9731511
SPARKASSE BOCHUM
BANK CODE 43 050 001
ACCOUNT No 5 401 070
www.einstein-audio.de
Warranty Card
Serial number
_____________________________________________
Owner’s name
_____________________________________________
Address
_____________________________________________
_____________________________________________
Purchase date
_____________________________________________
Dealer name
_____________________________________________
Dealer address
_____________________________________________
Important Note
To obtain the full 3-year warranty (6 months on tubes), we must receive
your warranty card and a copy of your sales receipt within 14 days of
purchase. Should you purchase your Einstein stereo amplifier from an
unauthorized dealer, the warranty period is limited to 6 months.
Unauthorized service or modifications null and void the warranty.
I
IBAN: DE26 4305 0001 0005 4010 70 SWIFT: BICWELADED1BOC
StNr.: 350/5024/0706 UstId: DE811577342