EA3 for 12 V triggering an amp

[Andrej2]

I have an amp that can be turned on by dropping a 12 V trigger voltage to 0 V. I'd like to use a relay in EA3 to do so. 

I wired it per the EA3 manual for a normally closed device (first attachment). The starting voltage between NC and +12 terminals is indeed 12 V. But when I try to control this voltage using the Composer amp remote (second attachment), nothing happens (that is, the voltage does not drop to 0 V, but stays at 12 V); the third attachment shows the driver for the amp, installed by my dealer. There is a red cross at the second button, seemingly indicating an issue. Pressing the first and second buttons produces a click sound from the EA3, the third one produces no sound. I am measuring the voltage using a simple voltage meter, without the amp connected. As an aside, wiring the EA3 terminal as suggested for a normally opened device, say a Fireplace (fourth attachment), does not work either.

What am I doing wrong? Should I connect the amp? Is the relay in my EA-3 broken? Am I using the correct driver (maybe I should use a driver for a Control4 amp trigger - which one is that)? Should I wire the EA3 terminal differently? I am assuming no external power is required for this very low-current trigger.

[WholeHomeControl]

I am not certain about a few things you've written, but here's what I would do:

1. First, I would simply ensure that you have proper control of the relay.  Set your multimeter to test for continuity, and then put the probes on COM and NC.  Can you successfully create and break continuity now by controlling the relay from Composer?  If not, this is where you need to focus.

2. Next, wire up per your original diagram but without connecting to the amp, as follows:

Now test voltage between the red and black wires.  Can you toggle between 12V and 0V by controlling the relay from Composer?

3. If you get this far, then everything on the Control4 side is correct and now it's just  question of whether your amp is responding to the voltage correctly.

 

[WholeHomeControl]

1 hour ago, Andrej2 said:

I have an amp that can be turned on by dropping a 12 V trigger voltage to 0 V. I'd like to use a relay in EA3 to do so. 

This is the part I am uncertain of.  Are you saying that with 12V applied to the amp, the amp will turn off, but when 12V is removed the amp will turn on?  I have only worked with a small selection of amplifiers, but this seems backwards to me.  Typically, you would apply 12V to turn the amp on, and without the 12V applied the amp would be off.  What model amplifier are you using?

[lippavisual]

Looks like its wired wrong to me.  The controllers provide their own 12v source.  Do not use an external power supply.  Wire it like this:

Short jumper wire from 12V to Com

Trigger tip/positive (to amp) gets wired to either NC or NO, depending on what your equipment requires.

Trigger sleeve/negative/ground (to amp) gets wired to GND.

 

Now on to drivers.  I'm assuming you are using a dumb amp (meaning, it doesn't need any control other than turning on).

You should use the C4 Power Amp 4 or 8 channel drivers, even if its not the correct brand.  Just rename it to what you want.

Then you need to bind the EA3 controllers relay to the amps trigger input.

Then you need to insure that any room using this amp has the audio endpoint 1 set to the amp.  Whatever device will be controlling the volume, mute of the signal will be set to Audio Volume 1 and if video audio runs through this too, Video's Audio Endpoint 1.

That's it.  Should be working now.  If the trigger isn't working, swap the wire between NC and NO.  I agree with the above statement that triggers are usually set to turn amps ON when supplying the 12v and off when 0.

[WholeHomeControl]

59 minutes ago, lippavisual said:

Looks like its wired wrong to me.  The controllers provide their own 12v source.  Do not use an external power supply.  Wire it like this:

Short jumper wire from 12V to Com

Trigger tip/positive (to amp) gets wired to either NC or NO, depending on what your equipment requires.

Trigger sleeve/negative/ground (to amp) gets wired to GND.

This post confuses me  

The OP’s picture DOES show that he was using the controller power, so not sure what the first paragraph means. 
 

Also, your prescribed wiring looks to be effectively the same as what the OP did. At the end of the day, when the relay is closed,  12V wires to trigger + and GND wires to trigger -  The only difference is which leg the relay shorts to close the circuit, which shouldn’t matter. 

[Andrej2]

5 hours ago, WholeHomeControl said:

This is the part I am uncertain of.  Are you saying that with 12V applied to the amp, the amp will turn off, but when 12V is removed the amp will turn on?  I have only worked with a small selection of amplifiers, but this seems backwards to me.  Typically, you would apply 12V to turn the amp on, and without the 12V applied the amp would be off.  What model amplifier are you using?

you are correct. i screwed up. 12 V is what turns it on (as long as it applies for more than 250 msec), and 0 V turns it off. it draws less than 5 mA at 12 V. i am testing the other suggestions next ... 

[lippavisual]

2 hours ago, WholeHomeControl said:

This post confuses me  

The OP’s picture DOES show that he was using the controller power, so not sure what the first paragraph means. 
 

Also, your prescribed wiring looks to be effectively the same as what the OP did. At the end of the day, when the relay is closed,  12V wires to trigger + and GND wires to trigger -  The only difference is which leg the relay shorts to close the circuit, which shouldn’t matter. 

You're right.  Victim of skim reading and thought the "12V trigger" box was a power supply.

Also correct on the wiring, but I've always preferred to switch the hot lead instead of ground.  Creature of habit.

[Composer4hire]

What Ive always done, on every amp for 12v regardless if it was a cheap crown or a 90k burmester is the following (utilizing 12v in and 12v out of amp)

This assumes only on and off control. works flawlessly and allows for power monitoring in composer

add 4 or 8 zone c4 amp driver (regardless of the amp manufacturer)

jump the common and 12v together 

N/O to positive 12v in/AMP

GND to negative 12v in/AMP

SIG to 12v out/AMP

GND to 12v out/AMP

 

might seem weird but it works every time

[Andrej2]

here's an update and at least a temporary conclusion, for what it is worth. 

the Composer driver for the trigger (one for shades, eventually) was confirmed to have worked, by measuring the voltage and resistance on EA3 outputs. but EA3 still didn't trigger my amp. my amps are Ayre MR-X Twenty mono blocks (they drive subwoofers in my integrated stereo and HT system). Per the manual, one of these amps can be triggered with a voltage of 5 - 12 V, drawing at most 5 mA (it can also be toggled by voltage pulses shorter than 250 ms, but I have not tried that, as it does not allow a convenient absolute control of on/off states); once an amp is triggered, a direct connection between the amps triggers the second amp. 

fortunately, i already had a working trigger setup previously, relying on a Global Cache relay (https://app.box.com/s/zuxaulm9vybmoswp69pyuf91dx577lkg), controlled by Global Cache iTach Flex Ethernet interface via a Simple Control app on my iPhone. The relay triggers the amp by toggling a 12 V signal from a small wall wart power adapter. 

the solution to my problem was that my dealer installed a C4 driver for the Global Cache ethernet interface. 

while i can control my amps with C4 now, it is still unfortunate that I could not replace the 2 global cache devices, a power adapter, and a bunch of cables with a single cable from EA3 to the amps. 

i don't know why EA3 didn't work, I think it should. My dealer hypothesized this: 

"The EA3 relay leaks voltage.  It looks like the MXRs are extremely sensitive to voltage on the input.  Once a state is initialized (on or off), switching the relay does not completely "cut" the voltage.  I can't measure that with your meter, but I can with mine."

Maybe I'd have more luck with using the relay in the C4 IR transmitter?

[Don Cohen]

I use an iNuke 6000 to power my subwoofer, and it doesn't have 12v or other means of turning it on remotely.  I opted to use a Control4 Outlet Switch, leaving the iNuke's power button depressed and in the 'On' position.  When I have Control4 turn on the entire theater, this is one step in the programming, and it has worked flawlessly.

Just a thought, which may or may not be applicable to your situation.

[Andrej2]

18 hours ago, Don Cohen said:

I use an iNuke 6000 to power my subwoofer, and it doesn't have 12v or other means of turning it on remotely.  I opted to use a Control4 Outlet Switch, leaving the iNuke's power button depressed and in the 'On' position.  When I have Control4 turn on the entire theater, this is one step in the programming, and it has worked flawlessly.

Just a thought, which may or may not be applicable to your situation.

yes, a reasonable idea, but in my specific situation two considerations argue against it: (i) the two mono blocks are also used in a highly optimized stereo system and i don't feel good about inserting anything i can avoid into the power line (probably a case of audiophile nervosa, admittedly); (ii) possibly more relevantly, the amps are actually in the sleep mode when they are off, still slightly warm, and it would take a while before they warmed up if they started cold each time. but i appreciate your comment!

[WholeHomeControl]

Woah, I would not have guessed the problem was a failure of the EA-3 relay to completely break the circuit.  

Perhaps installing a resister in-line (anywhere in the circuit) would make the difference. 

[lippavisual]

I've never heard of any controllers leaking voltage over the relays either.  Relay is either Open or closed, not in between.

The C4 power amp drivers are using 12v triggers, so either 0V or constant 12V when open/closed.

If the amps require short pulses, then ditch the C4 amp driver and add simple Relay driver.  Here you can define whether it's a toggle or pulse.  Then add programming for when room turns on, close relay.  When off, open relay.