"I'd assumed that, with so much processing going on in the following stages, the contribution of the transport to the overall sound of today's separate digital components was becoming less significant. Was I ever wrong! "
Stereophile, Sep. 2001
Over 12 years of research and development, Junji Kimura finally completed the design of PiTracer CD Transport. This machine is the reason he established 47 Laboratory in 1992 to devote his time and energy solely to his own concept. Along its twisted and winded pass, Junji gave birth to already familiar 47 components, Gaincard, Flatfish, Progression etc., etc., but
always at the core of his creative activity was the PiTracer. There were numerous prototypes, some shown at CES in early 90's, and recently in 2000.
Although those prototypes were enough to attract commercial offers from all over the world, Junji was not convinced those prototypes meet his criteria and we all had to wait until he gave a nod."Designing PiTracer" "NEW"
Now, the dream machine is finally here!
PiTracer will prove how much information were left unextracted in CDs or lost before they reach DA conversion. The first time in the history, we'll hear the true potential of the 16bit/44.1kHz format.
by Junji Kimura
PiTracer is strictly a 16bit/44.1kHz format transport. It does not come with any 24bit/96kHz nor HDCD compatibility. Junji states three major reservations about new formats.
Until those concerns are resolved, 47 Laboratory is not going to start any
project on new formats.
- Jumping onto a new format while you know there's still a great deal of
possibility to improve the current one is a deservice to customers.
- With a small number of software available in new format today, it is
doubtful if it ever establishes itself in the market.
- The quality of parts available today is not good enough to properly decode
- Drive mechanism
Direct drive with a highly sensitive, low inertia, high torque coreless
mortor (spindle diameter 3mm).
- Tracking mechanism
Thread drive mechanism with a combination of coreless motor, Kevlar core
thread, and V guide system. This mechanism was developed to adjust the
pickup-head itself to the off centering of CD. The lens, which changes the
angle in conventional CD transport to adjust to the off centering, stops its
movement almost competely. It dramatically lessens the fractuation of the
servo amount, also allowing the laser beam to hit the surface of CD at
constant 90 degrees for greater acuracy of focus.
The platform, machined out of 320w x 30h x 360d mmm aluminum block,
contains the spindle motor, sled motor, worm gear, V guide track, mortor
drive amp and output connectors.
- Head Casing
The head casing is machined out of 270w x 30h x 170d mm aluminum block.
The pickup head (CEC), circuitry and control keys are centralized on it to
release the movement of the pickup head from the stress of the multiconductor
- Motor Drive Amp
Four operation amplifiers, same grade as the one used in 4706 Gaincard,
are used to control the spindle motor and the sled motor. With the
combination of the simple mechanism, we realized a smooth and quick analog
- Turntable and Clamper
Both are machined out of solid acrylic. The CD touches the turntable
only at its inside and outside edges when it's clamped down, minimizing
the effect of the turntable material and overdamping.
The spindle and the turntable were machined again after the assembly
using a custom machining device to ensure the right angle.
The exact location of the turntable, the guide track and the pickup head
is also adjusted by a custom tool developed for the purpose.
- Power Supply
PiTracer is powered by Model 4700 Power Humpty. By adding another 4700,
you can power the motor drive section and the pickup circuitry separately.
Gear section and the guide system
- Outputs : 2 Coaxial BNC (1 DC coupled, 1 AC coupled) AES/EBU (optional)
- Power Supply : Model 4700 Power Humpty
- Finish : Black Anodized or Silver Hairline
- Dimentions : PiTracer 360(w) x 105(h) x 320(d)mm
Power Humpty 130(dia.) x 195(d)mm
gold-leaf, pigments on paper
156.4 x 364.6 cm
early 17th century