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Managing vibrations, a straight way to enhance audio performances
Last update on October 2008
Managing vibration in audio equipment is certainly the last thing people think about. Managing vibration greatly improve an audio rendering. Mechanical vibrations are as important as electronic. I provide a very simple recipe to put your system on top. [...] perhaps the only way to obtain extreme bass.
Managing vibration on all your equipments can improve sound more than you can imagine!

Ground and (safety) Earth
Last update on February 2008
Grounding and Earthing is wide problem on audio devices. Common user only care about parasitic current when hum or noise problem occur. At this point, audio signal is highly degraded. Even at very low level, parasitic currents dramatically damage sound performance...

Power supply (Shared Current Power Supply)
Last update on October 2016
Reflexion about the size of transformer and filtering capacitors in audio source (pre-amplifier, D/A converter...).

LM317, understanding and listening
Last update on July 2007
In this article I try many decoupling method an compare sound quality.

Listening digital filter
Last update on July 2007
  « It’s very difficult to compare different equipments and listening audio quality of the digital filter. The audio quality is the result of all the numeric and analog stages. The only way would to have different digitals filters on the same device »...

Comparing electrolytic capacitors
Last update on May 2008
  Black Gate, Elna Silmic II, Panasonic FC..., what model might I use for my device...

« Picking Capacitors » by Walter G. Jung and Richard Marsh
Picking Capacitors - part 1
Picking Capacitors - part 2
Last update on February 1980
  Article was published in Audio, in February of 1980. This two part article examined a number of capacitor types for performance characteristics relevant within audio application signal articles.

from Walter G. Jung's web site

Non-oversampling Digital filter-less DAC Concept by Ryohei Kusunoki
Last update on December 1997
  English translation about original articles « Non-oversampling Digital filter-less DAC Concept » by Ryohei Kusunoki.

from 47 laboratory, Sakura systems web site

Overview of Direct Stream Digital (DSD) signal processing
Last update on May 2001
  110th Convention of Audio Engineering Society, 2001 May 12–15 Amsterdam, The Netherlands.
« Why Direct Stream Digital is the best choice as a digital audio format ».
Derk Reefman, Peter Nuijten
Philips Research Laboratories
Prof. Holstlaan 4, 5656 AA Eindhoven, the Netherlands.

How (Not) to Decouple High-Speed Operational Amplifiers
Last update on September 2001
  Application report by Bruce Carter from Texas Instruments.
Decoupling the power supply pins of high-speed operational amplifier circuits is critical to their operation. Decoupling is also one of the least understood topics in engineering. It is seldom given the time or care required, yet it is a relatively simple. This document will explain the pitfalls in decoupling and offer some correct techniques.

from Texas Instruments

Biasing Op-Amps into Class A by Warren Young
Last update on March 2007
   "Class A" refers to configuring an amplifier so that its output devices remain turned on all the time. This reduces thermal variation and eliminates crossover distortion, which makes the chip perform better. To bias an op-amp into class A, you simply put a current source from the op-amp's output to one of the power rails. Everything else is details. This article is about those details.

from Tangent soft

Calculating optimum snubbers by Jim Hagerman
Last update on Jully 1995
   "A snubber is needed when an oscillatory circuit must be damped. Oscillatory circuits come in many forms but can often be reduced to a simple LC circuit commonly known as a "tank"..."

from HagTech