A few years ago I was caught by a malign bug: Building my own audio gear.
This is an awful lot of fun, but also frustrating and most of the time, very
expensive.
I have also scanned some pictures of some of the things I have built. You can read about these pictures as well.
There are also some pictures of things that others than myself have built,
including some interesting commercial products. The pictures of horn speakers
are described in a separate section of the Horn Speaker Home Page
I also have an archive of text files discussing a number of audio related subjects, most of which
is in English.
My system currently (July 96) consists of:
Turntable: Garrard 401 with SME 3009 II ("non-improved") in 65 kg. soapstone
plinth. A Shure V-15 tupe V-MR (MM) cartridge is fitted on the arm.
CD player: Slightly modified Sony CDP-797 (lots of silicone and asphalt
sheet and Jensen paper-in-oil caps at the output.
Preamp: Modified Loesch phono stage, using 417A, 6GK5 and 3A/167M, in that
order, from input to output. Tubed
3rd order crossover, 2 way with a crossover frequency of 500Hz. This xover
is a combined line stage and xover. Uses 1xE80CC, 2xE182CC, 1x12AU7WA, and
4xE88CC. Low-pass output has stepped attenuator for level matching.
Bass amp: OTL stereo triode push-pull amp using 1x12AX7WB, 4x6SN7GTB, 2x6EA7
and 8x6AS7G. This is an amp designed by Bruce Rozenblit and is inspired by
the old Julius Futterman OTL designs.
Midrange/treble amps: One pair of Single Ended two stage direct coupled amps,
currently using 6SG7 input/drive stage and RCA/Raditron UX245 output tube.
Dual pi-filtered power supply using Sangamo, Sprague and General
Instrument oil/paper caps. Output transformers are LL1623/90mA made by AB
Lars Lundahl. According to tube manual specs, the amps output a max. power of
about 2W.
Bass speakers: 'Push Pull Element Baffle Dipole' designed by Torbjoern Lien.
Each speaker uses 16 modified Audax 8" woofers in a sort of folded baffle.
All the drivers are connected in series, for a system impedance some place
in the 35-40 ohm range, yielding good power transfer and damping factor
with the OTL amp. Exceptionally tight and solid bass, very dynamic and
effortless and capable of very high SPLs at low distortion.
Midrange/treble speakers: JBL 2461 compression drivers fitted with D8R2425
titanium diaphragms on rectangular tractrix horns of my own design, though
strongly inspired by the Bruce Edgar midrange horn. (Speaker Builder 1/86).
Sensitivity is some place in the 105-110dB/1W/1m range. These horns try to
cover the 500Hz-20kHz range, but even with a gentle active EQ above 10kHz
the top octave remained a bit rolled off. Early July '96 I added a pair of
Electro-Voice T-35 diffraction horn tweeters crossed in with a passive
filter consisting of a single 1 uF (Sangamo paper/oil) capacitor at 10 kHz.