Speaker Builder: Open-Baffle Subwoofer Simulation with Akabak

Confronted with the impossibility to conduct reliable measurements in the low-frequency domain for his DIY speaker project, George Ntanavaras explores the alternative of relying solely on simulation software. To validate the design of an open-baffle subwoofer using the AKABAK software, created by German company R&D Team, he also explores the transition from measurements to simulation. His experiments contrast the near-field response measurements of his loudspeaker with the accuracy of the simulation using AKABAK.

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

For our readers who like to get hands-on with DIY projects, in this article George Ntanavaras describes the design and the construction of his PR-3 stereo analog preamplifier, offering three high-level unbalanced stereo inputs and two unbalanced stereo outputs. Most of the components for this design are contained on a single PCB. This article was originally published in audioXpress, January 2019.

In this article, George Ntanavaras explains how to build a turntable speed measurement device using a microprocessor-controlled device that measures the speed of a turntable's platter. The project uses an Arduino board and the Arduino software IDE, and a micro sensor manufactured by Omron to sense the platter rotation. This article was originally published in audioXpress, June 2018.

In this project article for audioXpress, George Ntanavaras describes the design and construction of a high-quality RIAA preamplifier for moving coil cartridges based on high-quality Analog Device AD797 op-amps designed for low-noise audio applications and driven from very low source impedance. This article was originally published in audioxpress, March 2014.

Here is a simple portable device from George Ntanavaras that can help answer the question about peak voltage and peak current requirements and whether or not your power amplifier is capable of driving your loudspeaker without clipping. This article was originally published in audioXpress March 2015 — Focus on Test & Measurement Edition. (Updated Dec 2015)

A design based on superior op-amps used in audio applications. A high-quality amplifier must drive high-quality headphones. This article describes the design and construction of a high-quality, high-power headphone amplifier.

In this article, George Ntanavaras describes the design and operation of a system consisting of the ACH-01 accelerometer and a preamplifier with an integrated analog signal processor. With this system, it will be possible to measure at the low frequencies the acceleration, the velocity, and the excursion of a loudspeaker cone. Also the panel vibrations of a loudspeaker cabinet will be very easily obtained. Originally published on audioXpress June 2011.