Turntable
April 16 st , 2008
ANALOG SOURCE INTRODUCTION
After 20 years spent trying to get the best signal
from a digital source, developing many DACs, I have decided to convert to
analog sources.
Beware, this doesn't mean that my DACs have a bad
sound. I think that my
DAC End is a
true reference without compromise, but when I have connected a turntable to
my actual system I got a totally different sound!
Even if my first test with a turntable was made in the
worst conditions, with many bad elements in the signal path (cheap
cartridge, ultra cheap tonearm wiring, old commercial phono preamp (Audiolabor
Rein), the result was still great.
I don't want to start here a discussion about the sure
benefits of analog vs. digital because anyone can read information about
this argument on Wikipedia article "Analog
sound vs. digital sound", in
SOUNDFAN
article and on many other articles published on
Internet.
The main analog sources are turntable and old analog
tape recorders as Revox B77 (see image).
There is a complete website about these analog
recorder on:
SOUNDFAN
where you can
find many informations.
Using old tape recorders is not easy and it is
extremely difficult to find high quality software.
Obviously, it is quite funny to see on eBay someone
selling tape recorded CDs, just to ear the problems of both sources!
Another problem with tape recorders is that the input
and output circuits should be redesign to get hi-end sonic performances.
So, if we consider these aspects, today the best
analog source is the turntable, nothing else.
TURNTABLE INTRODUCTION
My main idea was to build a
turntable starting from hi-end spare parts like Rega RB300 tonearm and
Origin Live or J.A. Michell platter/bearing system. Talking about the motor
controller, I have no problem to create a good PWM with a Microcontroller in
order to drive an hard-disk stepper motor as shown in
Ing. Charles Altmann's
idea
After a long discussion with a friend of mine, who
has a lot of experience with turntables, this project has been temporary
suspended. He asserts that the main sound characteristics of a
turntable depend on two components impossible to build at home: the
tonearm and the cartridge.
Therefore, I have started to evaluate the
different offers on the market and I have identified the following
interesting products in their category.
 |
Rega
Planar 3 / P3
glass platter
AC motor
value about £300 including the good
RB300 tonearm
|
 |
LINN
Sondek LP12
value about £1500 including the tonearm
|
 |
J.A.Michell
Engineering Gyro SE
Spider chassis, suspended stable sub chassie
Massive acrylic/vinyl platter
Inverted oil-pumping bearing
High-quality standalone DC motor
value about £1200 including the good RB300 tonearm
|
 |
Origin Live AURORA MK2
Platter made of propritery material.
Highly rigid sub-chassis exibiting low resonance due to its
unique, centre point support arrangement.
Ironless DC motor design with no 'cogging' effect.
value about £750 without tonearm
|
All UK companies, someone will think I love only
English products, but it is not true.
Probably there are also some Pro-ject, Thorenz ,
Dual and ClearAudio turntables with interesting characteristics.
THE MY START ENVIRONMENT
As a starting point an used Rega Planar 3 or P3
seemed to be perfect to do the first experiment with an analog source.
The main part of this turntable is the very good
tonearm used in many hi-end turntable with 4 x value.
Lots of people consider it a reference, even if I
don't like the AC motor.
see The long way to the analog paradise
