My Beautiful Michell Gyrodec SE
in Vinyl preamps
I bought my turntable in 2016, having read about Michell turntables on and off for more than 20 years. While working in Taiwan between 2011 and 2015, I visited a local Audio shop in Tianmu, Taipei where a full Gyrodec within its Perspex case was on display. It was a huge piece of machinery, but […]
So Just How Quiet is Your Phono Stage?
in Preamplifiers, Vinyl preamps
You may be in for a surprise: actually not that quiet! The reason of course is that the cartridge inductance and resistance dominate the noise in any decent phono amp. To get the best in terms of noise performance, you really need to keep the input referred noise voltage and noise current to a minimum. […]
RIAA Equalizer Amplifier Design
in Technical, Vinyl preamps
This article explores the fundamental’s of phono amplifier design, culminating in a few practical designs. Special emphasis is placed on overload margins (critical if you want good sonics from your EQ amp), driving the EQ network adequately and noise. RIAA Equalization Amplifiers V2.0 Below is the RIAA Calculator Excel spread sheet. Please read the article above, […]
MC Head Amp Circuit Compendium
in Technical, Vinyl preamps
Here is the new updated moving coil head amp designs compendium – updated 31 July 2019. The first file is a PDF compendium of about 28 different circuits with noise, distortion and current consumption details. All the LTspice sim files are zipped in the second file. What is immediately apparent from this is that having […]
Technical Requirements of Phono Preamplifiers by Tomlinson Holman
in Technical, Vinyl preamps
The two articles below were written in the 1970’s, nearly a decade before the arrival of the CD and the ‘perfect sound forever’ claim made by Philips. There was a lot of focus on phono amplifier performance at the time which it could be argued was triggered by the arrival of very high performance turntables […]
Richard Lee’s Ultra-Low Noise MC Head Amp
in Technical, Vinyl preamps
This design was a development of Marshall Leach’s MC head-amp from the 1970’s and to my knowledge, Richard Lee’s implementation presented here has not been bested in terms of noise – about 280pV/rt Hz in a well implemented exemplar. Importantly, it requires only about 12mA current in the +-15V rail powered version, and about a […]