Johan Bernstrom has been in the Hi-Fi design
and manufacturing business since 1967. The
Sentec brand name was registered in 1973.
Mr. Bernstrom is known in many circles as
being one of the most knowledgeable in tubes
and tube circuits in Sweden. He has amassed
over 30,000 tubes in his collection, more
than 15,000 are audio types. Sentec had
many successful products including the kit
series SE77 preamplifier, PA77 amplifier,
and SP77 speaker's. This series of products
was often considered the "Swedish Dynaco."
In the late 1970's Mr. Bernstrom brought
to market the SC8 preamp, PA8 amplifier
and and TU8 FM tuner. These were available
as kits and pre-built products which were
extremely popular in Sweden throughout the
1978 Mr. Bernstrom brought to market one
of the very first Mosfet amplifiers, the
120w mono amplifier named the ACM1. These
were considered by many the best amps of
the time. In the late 80's with the shrinking
Hi-Fi market in Sweden the budget series
9 was released which included the PP9 phono
preamp, the DiAna digital to analog converter,
SC9 preamp and PA9 power amp.
By the end of the 1990's Mr. Bernstrom
decided to go back to his former interest
in vacuum tube design. He studied and learned
tube audio transformer design and designed
and wound his own transformers for the power
amp M30 30 watt EL34 amplifiers using 5751
and 6189 tubes along with a passive preamp.
In 2002 Mr. Bernstrom decided to sell
his manufacturing facility and retire. His
plans for retirement include making small
production of his favorite tube projects
he thought about and collected during the
years. The series starts off with the EQ10
78RPM phono equalizer.