I had to redo my pcb design becasue of noise issues. That took some time. I'm know in the progress of writing the first lines of code for the firmware. I'm currently doing that using Platform IO with Visual Studio Code and the Arduino framework after trying some other frameworks and the EDP-IDF as well. The arduino framework might be the best choise for this project. I had some trouble with the SPI interface. Information on the internet about the ESP32 is not always correct. A lot of information says the SPI clock can be up to 40MHz and even up 80MHz. That is not entirely true. These frequencies are only when writing to a slave. When reading data from a slave the maximum us 26.6MHz. It also takes 3us to start the transaction and another 3us to end it. Eventually I managed to get around 100ksps from the ADC, 2 channels simultaneously. Unfortunatly I am not able the use the full 250ksps bandwidth of the ADC. I will need an FPGA for that, but I think 100ksps is enough for most of us. I'm currently busy writing the data aqcuisition part with sample averaging and the triggering for the oscilloscope mode. I already have a bit experience with that after writing the software for the Network Connected Signal Analyzer project a few years ago. My aim is to get a measurement resolution of 0.01db with this project. 

You are right there is a mistake in that revision I forgot to change in that revision. Thank you fot letting me know. If you have any other problem, let me know if I can help. 

Hallo,clock is connected with WIFI, but clock doesn`t work (only g-segments are lighting, - - - - - -  )puTTY shows (again and again):DNS_Host_By_Name_CB: pool.ntp.org -> no IP addressNTP_StartDNS_Host_By_Name_Init: err -5, pendingElektor page shows a (new) link to: https://www.ntppool.org/de/use.htmlQuestion:  are following lines from your manual still okay? :ntp set hostname "pool.ntp.org"ntp set addr 0.0.0.0ntp set method hostnamePlease could you help?Vielen Dank!Jochen

I am not aware of such a project (but I did not actively search for it). However, it should be quite easy to build an SPDIF input based on a standard SPDIF reciever chip and an USB Microcontroller. I will think it through and, maybe, open a new project.

Mal ein Tip von einem Lautsprecher Entwickler : Es ist keine gute Idee, Mittel-und Hochtöner so weit auseinander zu plazieren. Die sollten so dicht wie möglich zusammen sein. Beim Tieftöner zum Mitteltöner ist das nicht so schlimm da hier die abgestrahlten Frequenzen deutlich niedriger liegen.  Bei Ihrer Anordnung leidet nämlich das vertikale Abstrahlverhalten. Heißt, die Box hört sich anders an wenn man sitzt als wenn man steht. Dieses hängt noch stark vom Abstand zur Box ab, je dichter man vor der Box sitzt, desto größer ist der Unterschied. Ziel ist in der Akustik immer eine Punktschallquelle, optimal sind daher Breitbänder und Koax Chassis.