Audiotools (bookmark this page for further reference)


Introduction to Drivers

Introduction to carbon-based drivers

How balanced armature drivers work

How a dynamic driver works


How to describe Sound

Audio spectrum explained

Understanding audio frequency

Recording studio glossary

Stereophile audio glossary

Headphonesty audio glossary

Describing sound (Head-Fi)

Sound signatures explained

Audio terminology (SBAF)

(JK’s) iem test tracks explained

Audiophile acronyms


Pairing Source with Headphones/Earphones

Impedance demystified by Headphonesty

Headphone & amp impedance

Headphone impedance explained

Innerfidelity on output impedance

Innerfidelity case study on output impedance

Headphone impedance and sensitivity explained

Understanding amplifier power

Balanced and unbalanced connections


Tools for Testing/Measuring Audio Equipment

Frequency response vs amplifier output impedance calculator for REW software

Audio Check

Online tone generator 1

Online tone generator 2

Visual sine sweep 20 – 20,000 Hz

Interactive frequency chart

Speaker/earpiece test (left, right, polarity)

Calibrating and using a DIY rig for measuring frequency responses

How to Measure IEM’s Frequency Response (Headphonesty)

Online Convert for Headphone Sensitivity

How to test and assess the sound quality of headphones [ultimate guide]


Understanding Frequency Measurements

Headphone measurements explained (innerfidelity)

Crinacle’s graph 101: how to read measurements

How to interpret graphs (DIY Audio Heaven)

Online WebPlotDigitizer


Crinacle’s graph comparison tool


Digital Streaming

Whathifi explains Master Quality Authenticated (MQA)

Wikipedia: MQA

Whathifi explains Direct Stream Digital (DSD)

Cambridge Audio explains DSD

Wikipedia: DSD



Tweaking tips – a simplified guide to iem silicone eartips

The ultimate guide to selecting the perfect IEM ear tips
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  • Audiotools (bookmark this page for further reference) 1

    Head-Fier since 2016. He has been known as “Otto Motor” to Head-Fiers, as “Dr. Schweinsgruber” to users and Youtubers, and as “Brause” to Super Best Audio Friends and the Headphone Community. - For the purpose of confusion, he decided to pose under his real name Jürgen Kraus (“JK”) from now on. - This is a hobby. In “real” life, Jürgen is a professional geologist operating his own petroleum-exploration consulting company Franconia Geoscience Ltd. (see ad in the footer) based in Calgary, Canada. He holds German and Canadian passports. Jürgen had a classical music education from childhood through high school in Germany and he has been following popular music developments since the late 1970s. His understanding of arts and crafts was influenced by Bauhaus pragmatism: “less is more” and “form follows function”.