Die Homepage der Familie Beis

The Electronics Section of Beis.de


AMBM - The Analog Meter Bridge Module Project - Modules for DIY

DA2USB - Digital Audio to USB Interface - a kit for DIY

Interesting kits for DIY:

The 192 kHz audio ADC and DAC AD24QS and DA24QS,
the dual channel preamplifier AD-IOA for the AD24QS,
and the DA24QS' little brother DA24DS (96 kHz double speed)
The digital audio to USB interface DA2USB
Modules for finest meter bridges: AMBM

Versatile modules as kits for ambitious DIY multichannel meter bridges

  AMBM - The Analog Meter Bridge Module Project

  AMBM - Das Analog-Meterbridge-Modul-Projekt

With LED bars containing 51 dual-color LEDs such a meter bridge is not only technically valuable but an exceptional eye-catcher, too

PPM or VU measurements, bar display or dot display, high precision and many more features

Finally I have a great solution for how to get my ADC's (and other) digital audio signals into a PC:

  DA2USB - Digital Audio to USB Interface

  DA2USB - Digital-Audio-zu-USB Interface

DIY-kit with all SMDs populated

Driverless - no software to install
Up to 192 kHz/24 bit (Mac OS-X, Linux and Windows 10 from vers. 1709 on) and up to 96 kHz/24 bit and 192 kHz/16 bit (previous Windows)

An interesting project turned out to become the most useful and indispensable device for my digital audio developments I ever made:

DASG - Digital Audio Sine Wave Generator

A very precise and flexible digital audio signal source which probably every digital audio system designer should have for exact signal processing tests. At least I couldn't miss it any more.

A delta sigma based analog 1 kHz sine wave generator with the main intention to generate a precise 1 kHz tone for calibration of analog level meters

DS1kGen - Precision 1 kHz Audio Sine Wave Generator

No kits or so available, but I can help for DIY

Praxistipp: Wie kann man einen oder mehrere Oszilloskop-Tastköpfe in SMD-Schaltung kontaktieren:

  Zwei Beine für den Tastkopf

- Wenn 2 Hände zu wenig sind -

The ADICON Project

An ADC not only for HiFi-enthusiasts

I realized that in many audio devices correlation measurement is incorrectly implemented:

False and Correct Audio Correlation Measurements

How is it done there, how is it done correctly and how big is the error?

Up to now my most ambitious project, not for DIY:

   8-Channel Fully Digital Parametrical Equalizer

Will this ever become a product? Let me know your opinion.

Mein bisher anspruchvollstes Projekt, nichts zum Nachbauen:

   8-kanaliger, voll-digitaler parametrischer Equalizer

Wird das jemals ein Produkt werden? Lasst mich eure Meinung wissen.

I still enjoy contact to the DIYs around the world:

   24 Bit / 192 kHz Audio ADC AD24QS with the optional preamplifier AD-IOA, the
   Audio 24 Bit / 192 kHz DAC DA24QS and the
   24 Bit / 96 kHz Audio DAC DA24DS

The ADC, AD-IOA and DAC kits are available

Ich habe immer noch viel Freude an Kontakt zu DIYs in der ganzen Welt:

   24 Bit / 192 kHz Audio-ADC AD24QS mit dem optionalen Vorverstärker AD-IOA, the
   24 Bit / 192 kHz Audio-DAC DA24QS and the
   24 Bit / 96 kHz Audio-DAC DA24DS

Bausätze für den ADC, AD-IOA und DAC sind erhältlich

I always wanted to know how to do it (and now I do):

Converting Analog into Digital (IIR) Filters - A Recipe (almost...) -


Simple Conversion of 1st Order Analog into Digital (IIR) Filters
Using impulse invariant transformation instead of bilinear transformation

Including my program AnaDigFilt.exe that helps to find out the digital coefficients and lets you explore what happens in case you "play" with them

My Java-Script filter design utility is able to dimension active high- and low-pass filters and now even single stage, 3rd order, low-pass filters:

Active Filter Design and Dimensioning

Low- ang High-pass Filter

Over a long time delta-sigma codecs appeared to be a sealed book for me - until I started to teach myself:

   An Introduction to Delta Sigma Converters

(   Eine Einführung in Delta-Sigma-Wandler)

The "RF-Wallpaper" was a valuable aid for me from my early beginnings in electronics on. Now I made it myself and do not need bad copies from books any more:

The RF-Wallpaper / Die HF-Tapete


A nomogram, an online-calculator and some background information about

Resistor Noise / Widerstandsrauschen


Something completely digital, growing more and more luxurious:

The new VFD-equipped DPLCM-VFD

An FPGA-Based Digital Audio Peak Level and Correlation Meter with many features

is the successor of the LED-equipped DPLCM

How to measure different parameters on a condensor microphone capsule:

Backplate Voltage Driven
Condenser Microphone Capsule Measurement (CM2)

An experiment to design

An RF-Circuit for Condenser Microphone Capsules

The concept of an

Extreme Low Noise Preamplifier

with down to 0.45 nV/Sqr(Hz) or even 0.37 nV/Sqr(Hz) of input voltage noise

Frequency responses can be measured much faster than with sweeped sine signals:

Instant Audio Frequency Response Measurements using Soundcards, FFT-Software and Multi-Sine Signals

Some additional equipment for audio measurements:

Audio Preamplifier
Weighting Filter Set
Universal Filter

  An analog-to-digital- and digital-to-analog converter for the USB (in German only):



   My little POV-Ray Project was made during a few holiday days. It's German, but there is not much to read, there is more to see.

2 small articles of mine, on Rod Elliott's site
Reverse RIAA Equaliser: How to use a needless phono input as a universal line input?
Transformerless Balanced Line Driver with Floating Output: Amplifier with transformer-like output properties

(Note: Rod's website has moved and the links are updated now.)

Tut mir leid, leider übersteuert

I was curious about the inside of such a battery pack (updated):

Analyzing a Chinese Battery Pack Clone (updated)

Last update: July 23rd, 2018 Questions? Suggestions? Email Me! Uwe Beis