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An Archival Phono Preamplifier is a phono preamplifier designed for playback of vintage recordings – long-playing, 45- and 78-rpm records made before the RIAA curve was universally adopted by the recording industry. Broadcast transcription discs – normally 16-inch lacquer discs recorded at 33 1/3-rpm – also fall into this category, as do cylinders. Prior to the standardization of the RIAA curve for long-playing (33 1/3-rpm) records in 1956, the equalization curves used to cut phonograph records varied widely among recording companies. Engineers were sometimes known to change curves from one recording session to the next and, on occasion, from one side to the next in a multi-disc 78-rpm album. To help music lovers sort out this confusion, High Fidelity magazine regularly published a page called “Dialing Your Discs,” which offered recommended playback settings for most American Lp record labels. Although there are some (expensive) commercial preamps available with customizable replay characteristics, Gary Galo found them wanting and has over the years developed a phono preamp designed to replay all these different formats and recording curves. That design is described in this article.

The introduction of the "high resolution" digital formats for the recording of sound has initiated wide-ranging discussions on the audibility of the improvements, compared to the CD-format, which has been around for almost 30 years now. In this article, Hans van Maanen reviews some of the initial drawbacks of digital recording as well as the paradoxes it entailed. He uses some results from the analog era to illustrate that the CD-format has audible deficiencies and the paradoxes are explained by phenomena, which can be attributed to the anti-aliasing filtering and the interaction of the temporal and amplitude quantization. It is shown that the "normal" definitions of Signal-to-Noise Ratio (SNR) cannot be applied in the same way for digital systems as for analog systems.

In a previous article (Linear Audio Volume 0), Pierre investigated audio transformers as magnetic devices to determine and optimize leakage inductances. In the present one, Mr. Touzelet focusses on audio transformers as electrostatic devices to determine stray capacitances and their arrangement between terminals. Both viewpoints: the magnetic and the electrostatic are necessary and of the same importance, as they contribute to form a low pass filter, responsible of the high frequency response of audio transformers. Some general formulas are derived first, and then a method for estimating winding to winding and single winding stray capacitances is given, showing their arrangement between terminals, depending on the way windings are wound and terminals linked. Finally, he shows how these different stray capacitances combine into the capacitances across the terminals of an audio transformer.