You Can DIY!: PhL-100 - Α High-Quality MM Phono, Line, and Headphone Amplifier

Focusing on a practical, hands-on perspective, George Ntanavaras, details the design and construction of a phono preamplifier for Moving Magnet (MM) cartridges and a Line/Headphone amplifier with two additional inputs and volume control. All the amplification stages are based on top-quality audio op-amps such as Texas Instruments' OPA1642 for the phono stage and OPA1612 for the Line/Headphone stage. Almost all the components of the device are contained on a single PCB for easy construction. This article was originally published in audioXpress, February 2022

Expanding on previous articles about bass shakers and motion platforms, this article from Mike Klasco (Menlo Scientific) looks at exciting evolutions in haptic transducers and actuators that are being used in a growing number of applications - all of which depend upon audio sources for input. The ability to interact with the world through vibration and touch is central to all of our lives, and now increasingly so. This article was originally published in audioXpress, February 2022.

The Satori MW19TX-8 TPCD cone 7.5" woofer is the fourth TPCD diaphragm transducer to be explicated in Test Bench, the first being an Eminence compression driver and the remaining all woofers from SB Acoustics. The high-end MW19TX-8 has a substantial feature set with similar features as the rest of Satori series with TPCD cones, impressing immediately by its distinctive cosmetics and subjective performance, which this characterization illustrates.

This article details the Composite Sound journey that led to the extensive use of TPCDs for loudspeaker applications and the company's second-generation Metamodal technology. This new engineering approach allows designing loudspeakers tailored for an intended purpose, realizing a physical representation of a TPCD computer-simulated model that is only achievable through the company's unique proprietary production process. This article was originally published in Voice Coil, February 2022.

Rising demand for portable, light footprint voice recognition devices is fueling a growth of the tiny machine learning (TinyML) field. Offering a broader, high-level discussion specifically focused on voice recognition, Vikrant Singh Tomar, the founder and Chief Technology Officer of Fluent.ai, explains the impact for embedded voice and the overall audio industry. This article was originally published in audioXpress, February 2022.

The February 2022 edition of audioXpress is now available and features our annual Market Update on Microphone technology. Vikrant Singh Tomar discusses TinyML and Voice Recognition Technology On the Edge, Richard Honeycutt writes about Quantification of Speech Intelligibility, and Mike Klasco expands on audio applications for Haptic Devices. George Ntanavaras builds a phono and line/headphone amplifier project, Brian Bylenok proposes a refined Current Feedback Headphone Amplifier, and Richard Honeycutt reminds us that Tube Power Amps also have Classes. Now available in print and online.