The successful bipolar-output revision of the high-speed experiment. Replacing the LT1223 with an LT1056 and revising compensation produced stable hardware; the archive includes sine- and square-wave tests, the PCB work, Gerbers and LTspice files.

A vertical-MOSFET version of the fast LT1223 front end, built on a new PCB. The project record documents stability work, heatsink temperature sensing, bench waveforms and the compensation used to control ringing.

A supply-pin-driven LT1223 front end with lateral MOSFET outputs. The build progressed through oscillation diagnosis and compensation changes to a completed, very fast amplifier documented with final assembly photographs and extensive scope captures.

A passive current-dumping development documented from circuit and PCB through bench tests and finished hardware. The local archive supplies its LTspice simulations and board files; the linked discussion preserves the design context.

A 2024 return to the Circlophone concept using an op-amp input stage. The archive follows simulation, PCB manufacture, first tests, waveform checks, enclosure work and active cooling through the completed amplifier.

A completed revision of the Hafler-inspired amplifier using a Hawksford cascode VAS. Both channels were assembled and used; the record includes the revised circuit, PCB, measurements and final hardware.

A small quasi-complementary Wiederhold-style amplifier using fast HUF75842 N-channel MOSFETs. It was completed as a compact two-channel amplifier; this page is built directly from the working archive because it was not present in the old gallery index.

A simplified recreation inspired by Jim Strickland's Hafler P7000 and its unusual push-pull VAS. The hardware worked closely to the simulation and was completed as a two-channel amplifier.

A compact amplifier experiment preserved with its schematic, LTspice revisions, populated board, scope testing and assembled hardware.

A roughly 30-watt bipolar amplifier with predrivers, drivers and TIP3055/TIP2955 outputs in a triple-emitter-follower arrangement, combined with a Darlington VAS and two-pole compensation.

An LMK-family implementation using readily available 3055/2955 complementary output devices. The page preserves the circuit evolution, board construction, test setup and waveform record.

A previously unpublished build using a mirror-VAS direction. The working archive contains the simulation, Sprint Layout PCB, board package and construction photographs.

A Darlington-VAS amplifier developed on the reusable output-stage platform. The record covers simulation revisions, PCB work, assembly, offset checks and bench testing.

An Alexander-derived front end with a folded-cascode VAS, built on the modular MOSFET output-stage platform. Hardware, test images, PCB files and simulation variants are included.

Samuel Groner's front-end/VAS concept adapted into an op-amp-input power amplifier on a replaceable daughterboard and reusable MOSFET output stage.

An op-amp-input development of Hugh Dean's Alpha Nirvana Class-A amplifier. The page documents the as-built circuit, two channels, test waveforms, cooling and completed chassis.

A symmetrical hybrid joining Philips-inspired push-pull VAS ideas with the LMK approach. The final two-channel amplifier, boards, test results and numerous LTspice iterations are preserved here.

A higher-power LMK development using three output pairs. The archive records prototype boards, device matching, current sharing, protection changes, stability work and final assembly.

A modern adaptation of the Earl Rapp / Philips circuit using an op-amp input and lateral MOSFET outputs, built in an aluminum chassis with repurposed server heatsinks.

A quasi-complementary Wiederhold build using 2N3055 outputs. The project moved from initially oscillating hardware to a working revision and includes detailed bench and analyzer records.

A quasi-complementary version of Michael Wiederhold's 1977 topology using N-channel power MOSFETs, documented through board manufacture, assembly, simulation and bench tests.

A return to Michael Wiederhold's 1977 folded-cascode topology with an op-amp input and complementary lateral MOSFET outputs. The prototype worked without value changes from the simulation.

The Radio-magazine Lomakin-Parshin circuit became a working two-channel amplifier and the starting point for a long series of LMK variants. Original article material, PCB work, measurements and BJT/FET studies are included.

An adaptation of Ian Hegglun's square-law design using an op-amp input and vertical MOSFET outputs. The archive follows simulation, PCB and hardware work, compensation experiments, cooling and analyzer tests.

A personal build and development of Elvee's EZ-Dump current-dumping amplifier. Schematics, simulations, board layouts, construction photographs and QA401 measurements are collected on this page.

A completed build of the xrk971 / Hugh Dean Alpha Nirvana Class-A amplifier with external power supply, speaker protection and temperature-controlled fan cooling.

A personal build of Elvee's Circlophone concept. The substantial record includes circuit variants, PCB work, assembly, enclosure, clipping indicator and later measurement sessions.

An NMOS-family amplifier assembled in an aluminum chassis. The gallery records PCB revisions, construction, power supply, bench loading and the completed amplifier in use.

A distinctive NMOS amplifier housed in a hand-finished wood enclosure. Construction photographs cover the electronics, heatsinking, casework, final assembly and listening setup.

A high-power NMOS-family build documented through home-made and factory PCBs, SMD experiments, grounding corrections, loading tests, waveform checks and final test rigs.

A detailed Project 54 build record: home PCB work, populated boards, thermal assembly, switch-mode supplies, protection, enclosure and final testing. Local design PDFs and the LTspice file are provided.

A BuildAudioAmps Project 42 build with PCB layouts, BOM and design documentation, assembly photographs and bench-testing history.

A build based on Rod Elliott's Project 101 MOSFET amplifier. The gallery follows the boards, wiring, power supply, heatsinks, enclosure, testing and final assembly.

The earliest NMOS-family build in this collection, with an extensive chronological record of prototypes, wiring, grounding, chassis work, successive revisions and finished hardware.

DC detection, delayed connection and solid-state speaker switching developed alongside the amplifiers. Schematics, PCB layouts, device data and built boards are collected here.