Add 12 volt trigger to prosound amp?

A simple solution is to put together an electrical outlet in a job-box with a 12 volt relay providing the power switching to the outlet. I assume that you have a useable trigger output from your AVR or preamp.

You can make this little relay controlled outlet for about $20. I can supply a schematic if you need one. Or additional information.

http://sound.westhost.com/project118.htm

Instead of connecting it to a computer, you connectorize it to connect to your AVR. I use this in my music-server to shut the peripherals off when the computer goes into sleep mode. Works pretty good.

I don't have an exact parts list handy... but most of the parts can be found at a local radio shack or electrical parts house.

1 - job box to house the relay and duplex outlet
1 - DPST or DPDT relay (12 volt coil with contacts rated for 125v at 15 amps)
1 - duplex outlet with ground (same as used in your house)
1 - three conductor power cord with plug (length to be determined by you)
1 - two conductor control wire (length tbd by you) this plugs into your 12V trigger from the AVR or processor. You may need a one-eighth inch phono plug if the AVR has a one-eighth inch plug attachment.
1 - soldering iron and solder
1 - a few feet of 14AWG stranded wire to connect the relay and outlet within the job box

 

relay.pdf 15.1689453125k . file

you could also just buy a triggered outlet too

Do you know of any retailers or sources for triggered outlets?

Yeah here's one:
http://www.shopwiki.com/detail/d=110...jumpToFirst=t/

But where's the DIY joy in that? Not to mention if you have most parts (or know someone who does), it is far cheaper to build a triggered AC outlet than buy it...$50 - $60 for one triggered outlet, or $40 in parts (including powerbar) for multiple triggered AC outlets...for future proofing.

I agree , but I have never seen a 'cheap' triggered unit....not that I have really looked!

Here's a fairly inexpensive one:

http://www.smarthomeusa.com/ShopByMa...td./Item/SCG4/

Hi

Wonderful info guys....The list of apps looks great.....and i thank u....


staffingpower dot com

sentersoftech dot com

Use a Solid state relay with zero cross switching.

Huh?

A solid state relay is a relay that uses a Triac or inverse parallel SCR's as the switching element. Some have trigger circuits that switch the load at the zero cross, for smooth, RF free, load control.

Zero crossing switching is needed in this situation because?

Why would you want to switch at the peak?

With this type of equipment....why does it matter? The inrush is manageable.

The only place we use zero cross switching is for power applications where capacitive loads are switched for power factor correction.

We use it whenever we switch a large load, it doesn't add much to the cost, and allows the load to power up smoothly, without the burst of RF usually associated with it.

BTW, no-one said it was needed, it was suggested.

Reviving this thread as I built a 12v switched 20A outlet with a solid state relay.

It works, however, the amp is humming, similar to a ground loop hum. The hum actually comes from the amp, not through the speakers.

I tried a different (same model) relay with the same issue.

Do I need some transistor/capacitor or something across the 12v side or ???

All suggestions are welcome!

Sounds like the "solid state" relay is doing something nasty to the AC waveform.
Sometimes it's called DC offset.

Do you have an O-scope?
What is the relay's part number?

For starters, I've been lurking here for years. Haven't had a need to post, yet, because so far just searching the forums has always been able to answer my questions.

I'm adding a 12v trigger to the old Ashly FET-1000 that currently drives my subs. I've ordered a 25A solid-state relay to do the job, along with a heatsink (since it didn't add much to the cost), and it seems like a straight-forward thing to integrate it into the amplifier itself (there's lots of room inside the chassis).

My question is this: Once in awhile, I pull the Ashly out to do actual pro-sound things. And in that world, 12V triggers just don't happen: You show up, plug the amps in, turn them on at the appropriate time, and that's that. Meanwhile, at home, I really would rather have the amp (and its noisy fan, and the power draw) off when not in use, hence the 12V trigger from my AVR.

In order to do both things, I intend to use the Ashly's existing front-panel switch to bypass the SSR. Logically, it will do exactly what I want (it's just an OR gate), but in terms of practicality I'm just not sure since I've never played with SSRs before.

It seems to me that the SSR will always see either 120 or 0 volts across its output terminals, regardless. And to that end, it seems that it will be happy (ie: not catching itself on fire) in any configuration.

But I just want a second opinion before I wire the thing up.

When you refer to the SSR (Surround Sound Reciever) output terminals, are you referring to the audio output or a set of power outlets on the rear of the SSR?

He's referring to a Solid State Relay.


Yes, like any switch.