Pleiades Labs history

Unedited .


The Pleiades labs is possibly a failure.


It took nearly 47 years to find out the obvious. For example that 2 Beyer M55 microphones dirctly connected to an Uher 4200 analog recorder at 7.5ips can produce and record a great natural sound, Witt almost flat frequency response from singer's vocal chords to listener's brain.


Why?


Stupidity is one reason.


Here is a summary of the Pleiades labs history.


1972-1980
The only available recording reproducing equipment were 1 JVC portable cassette radio recorder and a Grundig transistor long wooden console radio and record player.
A new piano, gift by great grandfather Melelaos, become a very important tool for ear training, pleasure and lessons.
An electronic table game called Polycyclomatic allowed connection of electronic components to Germanium transistors for making oscillators or amplifiers (in class A operation).


1980-1990
Reproducing equipment including cassete recorder and record player by Metz.
Electret capsule mics bought, cardioid so resistance controlled diaphragm.
Constructing kits such as HF-65 by Jostykit.
Discovering Pink Floyd and major 7th chords.


1990-2000
A few years at university of Warwick in engineering electronics
Access to anazing books including Electronics - T.S. Gray, Elements of Sound Recording - Frayne, Wolfe, Practical introduction to electronic circuits - Jones, Electronics - Neil Storey, Feynman Lectures in Physics, discussions with Dr. R. Pettifer on noise, Fourier transforms, electromagnetic waves.
Access to many beautiful sounding pianos and to choir singing
Final year project on single ended triode 300B power amplifiers.
Experience at Audio Note UK
Finding by chance the Bach numbered bass composition manual at the appendix of Bach's biography - Spitta at a music library [Bach Bass Rules edited by Schmidt].
Purchasing 2 Grampian ribbon mics and a Ferrograoh series 6 recorder at a NEC? fest.
Back to Ελλας.
It's Internet time.
Pleiades rotating speaker conceived and promptly made. Connected to WLM organ Amelie's by the first Pleiades PCL 86 power amp with Hammond manufacturing company transformers.
Making recordings of rock band with the Grampian mics to Sowter transformers to Ferrograph. Very nice sound.
Access to AKG C12a and C24.
Buying Coles 4038.
Making electron tube mic preamplifiers, Pleiades V -4, -3, -2, -1,
Building Altec electron tube compressor clone after suggestion by Lefteris, then incorporating turbo sounding Singer patent. See previous posts.
2000-2010
At a studio recording 24 track analog.
Mastering from 1/4in tape at Abbey Road studios.
Back to Hellas.

Buying military signal transformers from surplus yards after Lefteris suggestion.
It's eBay time.
Buying the main monitor reference, Sennheiser HD580 sugested by Lefteris. Trying RCA BA-6A limiter. Cinema engineering EQ.
Trying RCA 44 ribbon microphone.
Recording to Philips CD-R ADC modes after suggestion by Panayiotis.
Recapping various Oberheim synths, drum machine, Yamaha DX7ii etc.
By Albert's influence Pleiades tuning conceived, applied to DX7ii, Korg Triton.
Building U47 VF14 amplifoer clone by Leferis suggestion. Buying Sennheiser MD421 suggested by Yiannis.
Making Pleides T1 K116 by Panayiotis influence.
Making Pleiades V1, electrometer tube with AAA battery. Sean Davies sugested electrometer tubes.
Pleiadss electrical utility off grid since 2008.
Buying battery powered Tacam Porta 01, 02, Sony TC-D5 pro, Marantz MD-430.
Adding a coil (Pleiadss filter) in parallel to the low Z capsule of SM58 for low cut and recoding nicely to Sony TC-D5 Pro


2010-

Pleiades Electra 1, 2, 3 one electron tube power amplifiers
Pleiades L microphone filters


Rediscovering that the aim is flat frequency response not from mic to loudspeaker but from producer's brain to listener's brain [Lowe, Morgan]

Rediscovering that low acoustic sound pressure levels can lead to singing in tune [Stevens], [Ramone].
Rediscovery that grid is already negative by cathode emission. A pull up or Pleiadss bias from anode or Vb to grid by a Hugh Megohm resistor makes low noise operation possible at even 3.6V at anode or plate.
Pleiades battery powered electron tube microphone booster preamps V2, V3, V4, V5, V6

Pleiades 2N3053 one transistor power amplifier.
Pleiades R,L gentle low cut microphone filters
Testing as many world class mics from Shure, Elctro-Voice, Sennheiser, Beyer, Paso, Shaub Lorenz


Buying 2 fabulous Uher 4200 report recorders





References:


Sound and Hearing - S. S. Stevens, Fred Warshopsky - Life Science Series


Making Records - Phil Ramone


Bach Bass Eules: https://normanschmidt.net/scores/bachjs-general_bass_rules.pdf


Sound Picture Recording and Reproducing Characteristics - D. P. Lowe, K. F. Morgan - Journal of the society of motion picture engineers