Violectric's high-end amp houses three front-mounted headphone outputs: balanced 4-pin Neutrik, 4.4mm Pentaconn and ...

If you just want to dip your toe in the tube world, though, there’s a cheaper and more accessible way to get started. [Jenny List] shows us the way with her neat headphone amp build.

Questyle’s M18i mobile headphone amp, which just debuted at CES 2025, might look like a typical dongle-style DAC/amp — it actually bears a strong resemblance to the company’s M15 DAC/amp ...

The K2-W vacuum-tube op amp has an LTspice-simulated open loop gain of 27,000. The modeled K2-W input impedance is >100 MΩ. The LTspice modeled result shows 1.00 nA of input current.

After a brief review of the history of the K2-W vacuum-tube op amp, an LTspice model is used to create its schematic in preparation for SPICE simulation.

Headphone Amps HiFiMAN Goldenwave GA-10 Headphone Tube Amplifier: Preview At $1,599, the HiFiMAN Goldenwave GA-10 Features Top-Shelf Vacuum Tubes and a Specially Designed 120W Transformer.

At the time this thing with some small modifications could compete with amplifiers and 4 times the price (based on what I've read). So why not carry on the legacy of an absolute entry level vacuum ...