Power ON delay for amps

I've switched from using the MIDI NoteOn/Off messages to the sys-ex messages documented in the Hauptwerk User Guide under the section MIDI Console Status Output System. Besides the Organ Ready message I use several others to keep my transpose code in sync with HW, to operate a series of crescendo lamps, to light a sfortsando lamp, and for other status items.

I've used SSRs to switch power and usually like them except when they leak enough AC to turn on a small circuit. I've also used an enclosed relay from Sparcfun that is available assembled or as a kit. Both the SSRs and bare relays belong in enclosures of course, even inside your personal console in my opinion. Nothing wrong with any of the approaches mentioned. Off the shelf items will cost more but require less effort to implement.

Contrary to popular belief one should not use a zero crossing solid state relay on an inductive load such as a transformer. Random turn on relays should be used.

Eric

Has anyone used MONOPRICE Pro Audio 8" Powered Monitors? They seem to have a pop no matter what sequence you power devices. The sound seems good and the price for a pair is reasonable, especially on sales.

Looking at reviews on these monitors, the popping sound is obviously a design issue. I have both Mackie and Behringer, and the Mackie's have little of this effect, with the Behringer's more so.

Eric

This is another solution that I've used to avoid the pop with my saffire 40:

http://www.amazon.com/Pyle-PDBC70-Mountable-Protector-Control/dp/B00BQO5S0G/ref=sr_1_1?ie=UTF8&qid=1453929858&sr=8-1&keywords=pyle+power+strip

It's a pyle rack-mountable power strip / protector that allows each outlet to be turned on one-by-one. It's a manual solution, but it works very well and very simply. I just boot up the saffire and then turn on my speakers a second or two apart each. Or, to power down, I turn off the speakers and then the saffire. Easy. (And it makes for a much more robust surge protector, especially when plugged into a power conditioner.)

This is what you need: https://energenie4u.co.uk/catalogue/product/ENER011
You can program it to respond to computer events such as shut down. Thus you don't have to guess at delay times.
The other alternative is to use some MIDI hardware responding to HW messages which control a relay to switch amps on and off.

Would not work in North America.

Rgds,
Ed

It would be simple to program a Teensy or other Arduino device to switch a relay when HW outputs the Organ Ready signal. If this is still of interest to anyone I could come up with the program. Better yet, someone who already has a Teensy device could do this.

I'm experimenting with one of these. Hope to have more info to share soon.

There're reasonable inexpensive for what you get but it may be overkill for a HW setup...

http://www.digital-loggers.com/lpc.html

I simply use a time delay on relay. This is rated at 5A. I then operate a solid state relay rated at 20A because I am cautious. The time delay is set to 5 minutes since that is the boot time plus the time taken to load Hereford. The main power is switched on by Wemo from my smart phone.