- Joined
- Jul 11, 2005
- Messages
- 124
Dear DIYers,
during covid I started this monitorcontroller project. I am pretty far into it right now but there are some little problems you maybe can help me with.
First I want to describe the project. It was inspired by igors monitor controller, that unfortunately is not available anymore.
the monitor controller consists of
- a mainframe with all the audio inputs and outputs and the relay matrices and a talkback input/output.
- a remote control connected with ethernet cable to the mainframe that communicates over i2c with the mainframe, it also has a headphone amplifier built into it and houses a metering circuit.
the monitor controller has the following functions:
- switching between sources (4 stereo inputs) and destinations (4 stereo outputs)
- level control over relay attenuator (63steps/1dB)
- mono (with compensation)
- dim (dim level can be user programmed 0 -20dB)
- cut (LR, L or R)
- polarity inverse L and/or R
- LR swap
- Talkback (latching or momentary, user programmable TB-dim)
- 3 user programmabel preset levels for fast access
- 3 digit display
- rotary encoder for level setting and programming
- outputs can be programmed for a certain dimlevel in 0.25dB steps (up to 15dB)
- inputs can be programmed with offset of +-10dB
Problems:
On the picture you can see the remote control module. the lowest 2 bars of the meter leds are iluminated even with no audio signal present. is that a digital crosstalk from the i2c communication? why only on one side?
and I also hear some very low volume clicks in the headphone part (which takes only the + part of the balanced source to the control unit) when I am changing parameters on the monitor controller. What could that be? would it be better to buffer these sends to the remote on the mainframe?
![IMG_7220.jpg IMG_7220.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/60/60508-5be5f57cf2200f5fa3cded9a37a3e9a6.jpg)
frontside of remote control pcb
some more pics:
![IMG_7222.jpg IMG_7222.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/60/60509-cd3f6908fa397b2910eb57604db81157.jpg)
rear side of remote control pcb
![IMG_7221.jpg IMG_7221.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/60/60510-6593b8b49a1191cc3cef0071008dc47e.jpg)
mainframe pcb in temporary case
during covid I started this monitorcontroller project. I am pretty far into it right now but there are some little problems you maybe can help me with.
First I want to describe the project. It was inspired by igors monitor controller, that unfortunately is not available anymore.
the monitor controller consists of
- a mainframe with all the audio inputs and outputs and the relay matrices and a talkback input/output.
- a remote control connected with ethernet cable to the mainframe that communicates over i2c with the mainframe, it also has a headphone amplifier built into it and houses a metering circuit.
the monitor controller has the following functions:
- switching between sources (4 stereo inputs) and destinations (4 stereo outputs)
- level control over relay attenuator (63steps/1dB)
- mono (with compensation)
- dim (dim level can be user programmed 0 -20dB)
- cut (LR, L or R)
- polarity inverse L and/or R
- LR swap
- Talkback (latching or momentary, user programmable TB-dim)
- 3 user programmabel preset levels for fast access
- 3 digit display
- rotary encoder for level setting and programming
- outputs can be programmed for a certain dimlevel in 0.25dB steps (up to 15dB)
- inputs can be programmed with offset of +-10dB
Problems:
On the picture you can see the remote control module. the lowest 2 bars of the meter leds are iluminated even with no audio signal present. is that a digital crosstalk from the i2c communication? why only on one side?
and I also hear some very low volume clicks in the headphone part (which takes only the + part of the balanced source to the control unit) when I am changing parameters on the monitor controller. What could that be? would it be better to buffer these sends to the remote on the mainframe?
![IMG_7220.jpg IMG_7220.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/60/60508-5be5f57cf2200f5fa3cded9a37a3e9a6.jpg)
frontside of remote control pcb
some more pics:
![IMG_7222.jpg IMG_7222.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/60/60509-cd3f6908fa397b2910eb57604db81157.jpg)
rear side of remote control pcb
![IMG_7221.jpg IMG_7221.jpg](https://cdn.imagearchive.com/groupdiy/data/attachments/60/60510-6593b8b49a1191cc3cef0071008dc47e.jpg)
mainframe pcb in temporary case