Book Review: Burkhard Vogel’s Slopes and Levels. Spice Models to Simulate Vintage Op-Amp Noise

Interested in accurately simulating the noise of op-amp circuits? Audio electronics expert Burkhard Vogel wrote a book that addresses this relevant topic for any audio circuit designer that doesn't want to rely just on manufacturers own models. In this review, Marcel van de Gevel explored the full book after he read Vogel's introduction, explaining that some manufacturer-supplied simulation models are way off.

In this article Scott Dorsey tells us how to repair Switching Mode power supplies. As he explains, "there are a lot of books and articles out there about how to design a switching supply, but not many on fixing them. As switching supplies become ubiquitous in electronic devices today, it becomes that much more important to understand how they work and just as importantly how they fail." This article was originally published in audioXpress, January 2018.

In this article, Joel Hatch explains how to build a variable frequency synchronous motor controller to control turntable speed. Now that turntables are back in force, this excellent project not only allows some knowledge about a vital part of the motor's rotational speed adjustment, but it also dives into one of the most crucial aspects of a record player for anyone interested in a little DIY or restoration projects. This article was originally published in audioXpress, December 2010.

Peter Delos details how to add tone controls to a three-channel tube-based guitar preamplifier. The circuit is a versatile building block anyone can use for his or her own preamplifier applications. The project is implemented with three 12AX7 gain stages. The tone control at the final output is a standard bass, mid, treble control circuit found in many guitar amplifiers. This article was originally published in audioxpress, October 2014

Accurately setting the bias level for push-pull output stages is important to maximize amplifier performance and tube life. This circuit measures error relative to the target bias current and error relative to a balanced condition in the push-pull pair. The meter is compact, low-cost, simple, and accurate thanks to the use of a window comparator IC - a Linear Technology LTC1042. This article was originally published in audioXpress, July 2012.

Analog Devices announced the completion of its acquisition of Linear Technology Corporation, announced in July 2016. The combination creates a premier analog technology company with the industry’s most comprehensive suite of high-performance analog offerings and integrated engineering, manufacturing, sales and support operations that will accelerate innovation and revenue growth opportunities.

Consolidation continues in the electronic components’ industry. This time is Analog Devices acquiring Linear Technology, the established manufacturer of analog integrated circuits for power management, data conversion, signal conditioning, RF and interface ICs, µModule subsystems, and wireless sensor network products. According to Analog Devices, highly complementary product portfolios, engineering talent, technology, and application domain, creates an industry leader across all its major product categories.