From the Vault: The Borbely Preamp

"Designing a preamp is probably the most challenging engineering task in the audio chain, and many designers have invested a lot of time and effort in it," wrote Erno Borbely in this original 1985 article for the Audio Amateur. "My reason for designing this preamp is quite simple: I wanted to have a top-quality preamp without paying megabucks for a Levinson or Accuphase unit. It is up to you to decide whether or not I have succeeded in achieving the same quality." This article was originally published in The Audio Amateur Issue 4, 1985, and is still frequently referenced.

One of the strongest issues ever in terms of audio electronics and market insights, audioXpress July 2021 is now available. This edition includes a complete overview of Audio Amplifier Technology and Design and its many application segments. Start with a review of the NAD Electronics M33 Masters streaming amplifier, followed by a great new upgrade design for the legendary Hafler DH-220 lateral MOSFET power amplifier, and then dive into a new hybrid voltage source and current source amplifier design for loudspeakers.

With its 30th-anniversary year fast approaching, British manufacturer Chord Electronics has launched ULTIMA, a new state-of-the-art flagship amplifier featuring John Franks’ latest circuit topology, the first all-new design in three decades. The company introduces the ULTIMA mono amplifier and the matching preamp as "the ultimate expression of the finest high-performance, ultra-fast, ultra-high-power amplifier technology available today." The ULTIMA set (pre and 2x mono power amps) is available for £90,000 (approx. $116,000 USD).

Chord Electronics has chosen High End 2018 to unveil a brand new analogue amplifier topology design, the company’s first for nearly 30 years. Although many improvements have been introduced along the way, the new Choral Etude stereo power amp provides a glimpse of what's coming for the British company, "highly advanced, it heralds a new era for powerful, wide bandwidth, low noise and low distortion amplifiers," Chord states.

Chord Electronics has significantly upgraded its popular SPM 1050 power amplifier to MkII status, introducing a raft of internal upgrades, plus a number of aesthetic improvements over its predecessor. Chord Electronics’ new SPM 1050 MkII 200-watt power amplifier, first unveiled at High End 2016, Munich, is now available worldwide. The new MkII version directly replaces the original and introduces the latest Chord amplifier technology, plus some key aesthetic improvements.

A great solid-state project where National Semiconductor’s (since 2011, a part of Texas Instruments) LM4702 meets up with Renesas lateral MOSFETs, this article by Jack Walton was originally published in audioXpress July 2007 and it is still cited as a reference today. An ideal project for the DIY enthusiasts.