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

Zwei Beine für den Tastkopf

The ADICON Project

Interesting for DIY:

The 192 kHz audio ADC and DAC generation 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

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

DIY-kit with all SMDs populated
Driverless - no software to install
Up to 192 kHz/24 bit (Mac OS-X) and up to 96 kHz/24 bit and 192 kHz/16 bit (Windows)

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

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 electroncs 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
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: May 25th, 2016 Questions? Suggestions? Email Me! Uwe Beis