Please see all COVID-19 updates here as some shipments may be delayed due to CDC safety and staffing guidelines. If you have an order or shipping question please refer to our Customer Support page. For technical questions please check out our Forums. Thank you for your continued support.


Member Since: December 14, 2011

Country: United States

  • ouch, it's past midnight in Colorado, and 11pm in California! I missed the Arduino Day :-(

  • Hello Dave,

    Thank you for your note. It seems that our projects have some similarities.

    Here is how I solved my 2 problems:

    1. crosstalk was carried on the +12V wires, not the ground. I experimented with LC filters and found a good one. The idea is that the large cap (15mF) near each amplifier board provides for the current spikes. It is fed at a constant rate from the power supply through a L, containing the current spikes within each board

    2. idle noise is suppressed using the "mute" signal. I control the amps with Linux boards and I use a GPIO from the CPU to control the amps mute

    I started reading your website. Looks great, and I am looking forward to reading more; I'd like to stay in touch with you for future projects. This one was a quick demo, but if it catches up I will need to improve and make it a real product.

    fyi, I've been using a switching PSU, salvaged from a PC, and it was OK for the amps (+12V) but not OK for the Linux boards (+5V). Too much noise. I used a separate switching PSU for the 5V, it is very clean, but now I have to be smart about tying the grounds together for the "mute" feature. Any idea or best practice?

    Cheers, -karim

  • Hello,

    I bought 7 kits to make a multi room, multi zone audio system. I installed them in a big box, in the basement, next to each other.

    I am having 2 problems:

    1. crosstalk between rooms. If one module is cranked up, and another is not used, i.e. input not connected but normal gain (half way), there is some crosstalk. I use a PC power supply to power them. I think the crosstalk goes through the +12V power wires. How come? What's happening? How can I fix it?

    2. idle buzz. When the system is not in use, the input is disconnected, but the gain is at its normal setting (half way,) there is a faint buzz on the speakers. How can I alleviate that issue, since I cannot remotely control the gain potentiometers. What about the STBY vs MUTE? What's the pro/cons?

    Thanks in advance. -k

  • hey, thank you for the "parts wish list" list! I already have a great soldering station, but I need everything else from that kit, and it is really helpful to have a list. thanks, -k

No public wish lists :(