Archimago's Musings: MEASUREMENTS / MUSINGS: Headphone impedance, sensitivity, efficiency, and amplifier output impedance. (And a quick thought on Darko's "All You Need Is...")
Output impedances effect explained : r/headphones
The Complete Guide To Understanding Headphone Impedance
How does an amplifier's output impedance affect the sound of headphones? - Quora
audio - How do PC sound cards cope with headsets of different impedance? - Electrical Engineering Stack Exchange
Scarlet 2i4 amp headphone impedance? - Gearspace
Amp up your cans: Is your op amp stable? (Part 2) - Precision Hub - Archives - TI E2E support forums
Match-making For Headphone Lovers Pt.3: Impedance | The Ear
Should you get amped up about high-impedance headphones? | TechRadar
Headphone amplifiers - do they make audible difference (output impedance) - test | Audio Science Review (ASR) Forum
Headphone impedance and its effect on frequency response – SoundID Reference
Headphone Impedance And Sensitivity Explained | The Master Switch
What Is Output Impedance?
Things to Know about Headphone Impedance and Sensitivity
Phones & Ohms
What is Headphone Impedance? – Apos
Headphone outputs : lots of measurments and one ABX | Headphone Reviews and Discussion - Head-Fi.org
Headphones & Amplifiers - Output impedance, load impedance and frequency response
What is Headphones Frequency response, impedance and sensitivity? - Samma3a Tech
What Are Headphone Impedance and Sensitivity? – Apos
Effect of source output impedance on headphone frequency response | Headphone Reviews and Discussion - Head-Fi.org
Between the Ears: the art and science of measuring headphones Page 4 | Stereophile.com