BraveSirRobbin
Moderator
I had this problem when I switched the Elk using the mod for pre-amp output. Probably not applicable in this case though. I'm not sure how you would get rid of that pop when using line level. Capacitor perhaps?
How to use Elk Relays as speaker switches?
- Thread starter Galun
- Start date
apostolakisl
Senior Member
As far as the hum. Did you put the capacitor in (I am guessing that this was designed for hum which is why it is listed as optional)? Are you running the wires next to any power cords or other sources of interference? The hum is probably 60hz power line noise.
As far as the pop. I am not sure how to get rid of that. It may be that you need to use different relays that don't cause a little voltage pop with contact.
Edit: I see that they make shielded relays. The relay coil can induce a potential in the contacts when not shielded. This is a problem when the signal being switched is getting amplified (a small voltage spike gets amplified by the amplifier, not a problem when switching speakers since the signal is getting amplified after the relay). Read the last paragraph of this.
http://www.geofex.com/Article_Folders/relays/relays_for_switching_audio_signa.htm
As far as the pop. I am not sure how to get rid of that. It may be that you need to use different relays that don't cause a little voltage pop with contact.
Edit: I see that they make shielded relays. The relay coil can induce a potential in the contacts when not shielded. This is a problem when the signal being switched is getting amplified (a small voltage spike gets amplified by the amplifier, not a problem when switching speakers since the signal is getting amplified after the relay). Read the last paragraph of this.
http://www.geofex.com/Article_Folders/relays/relays_for_switching_audio_signa.htm
I did put in the capacitor but the hum is still there. It is close to speaker wires and power sources, yes. The hum is there only when the relays are off. I can live with this by putting the Sonos in the relay on position and the elk output in the off position when there is humm. I intend to have to elk make announcements only for emergencies and I sure hope there won't be many!
Another thing I noticed is that the Elk first few spoken words are dropped. Perhaps a second or two, don't know the percise time. When I put in "test test test test test test", I hear the last three test. When I put in "master bedroom left window test test", I hear "...om left window test test". So it does seem to be a fixed amount of time. Any thoughts on this observation? It's almost like some of the initial signal is "gobbled up" before the rest goes through. Could it be the capacitor? I roughtly know capacitors act like a reservoir before letting the rest of the electricity through after it's filled up...
And just in case I got it wrong, the capacitror I got this one from radioshack. http://www.radioshack.com/product/index.jsp?productId=2102481
Thanks!
In case the pop gets bothersome, I guess I can go back to the speaker level a/b switch idea with an Elk-800. Or I can drop the a/b switch and use elk relays to switch the amplified sources: Amplified AV/receiver output to NO, Amplified Elk-800 output to NC, COM to speaker selector. There shouldn't be any pop in this case?
Another thing I noticed is that the Elk first few spoken words are dropped. Perhaps a second or two, don't know the percise time. When I put in "test test test test test test", I hear the last three test. When I put in "master bedroom left window test test", I hear "...om left window test test". So it does seem to be a fixed amount of time. Any thoughts on this observation? It's almost like some of the initial signal is "gobbled up" before the rest goes through. Could it be the capacitor? I roughtly know capacitors act like a reservoir before letting the rest of the electricity through after it's filled up...
And just in case I got it wrong, the capacitror I got this one from radioshack. http://www.radioshack.com/product/index.jsp?productId=2102481
Thanks!
In case the pop gets bothersome, I guess I can go back to the speaker level a/b switch idea with an Elk-800. Or I can drop the a/b switch and use elk relays to switch the amplified sources: Amplified AV/receiver output to NO, Amplified Elk-800 output to NC, COM to speaker selector. There shouldn't be any pop in this case?
BSR, I am actually having the exact problem as you. My sonos line in is equivalent to your PC speaker line in from home seer. My Denon AV/Receiver is the Elk-800 in your diagram.
Looks like you dropped the 10 uF capacitor. I will try that out.
The other thing you or someone else mentioned is using 10K and 1K resistors instead of 6.8K and 680K. What does that do?
Thanks!
apostolakisl
Senior Member
I am not sure I understand exactly where the humm is comming from. You say it is when the relays are "off". So it will humm in the NC position regardless of whether you have music or the Elk plugged into the NC contact? Or, does the humm always follow the Elk?
My expectation is that the humm is comming from the Elk speaker output turned to a line output. Try just plugging the Elk line-out directly into your amp and see if there is a humm. If there is, then you know it isn't the relay. Also, see if there is a humm with the amp connected to the relay's common side, but with the NC and NO connections empty. If you have a humm now, it must be some inductance in the relay.
As far as the delay, I assume it is because the relay isn't switching over prior to the words being output. I really don't think it is the capacitor, but I suppose you could try removing it and see. The easiest way to know if the relay is switching over late is to (like above) plug the Elk line-out directly into your amp and see if you still lose the first few words.
In summary, plug the Elk line-out directly into the amp. If the humm is gone and the loss of the first few words is fixed, then the relay is your problem.
My expectation is that the humm is comming from the Elk speaker output turned to a line output. Try just plugging the Elk line-out directly into your amp and see if there is a humm. If there is, then you know it isn't the relay. Also, see if there is a humm with the amp connected to the relay's common side, but with the NC and NO connections empty. If you have a humm now, it must be some inductance in the relay.
As far as the delay, I assume it is because the relay isn't switching over prior to the words being output. I really don't think it is the capacitor, but I suppose you could try removing it and see. The easiest way to know if the relay is switching over late is to (like above) plug the Elk line-out directly into your amp and see if you still lose the first few words.
In summary, plug the Elk line-out directly into the amp. If the humm is gone and the loss of the first few words is fixed, then the relay is your problem.
Tried it. Connected line out directly to amp.
Humm is gone. So the relay is probably introducing the humm. Here were my steps of troubleshooting so far.
Scenario 1) Sonos to NC, Elk to NO, Amp to COM. In off state the Amp plays the Sonos, and in on state the amp plays elk. No humm at first from Sonos. Turn relay on, hear pop, and constant humm. Turn relay off, hear pop, Sonos plays but there is still a constant humm.
Scenario 2) Sonos to NO, Elk to NC, Amp to COM. In off state the Amp plays the elk, and in on state the amp plays Sonos. Turn relay on, hear Sonos, no humm. Turn relay off, hear pop, and constant humm. Turn relay back on, Sonos plays, and the humm is gone.
I notice that when I unplug the RCA jack and put it back in, sometimes the humm will be gone. But when I mess with the relay on off again, the hum is back.
On the delay, this is back to line out directly connected to amp, the delay of the first few words is still there. Behavior exact same as before.
apostolakisl
Senior Member
You must have some grounding issue using the Elk relay. I think you are probably going to have to use a separate relay to switch since the Elk ones are giving you humms and pops. This isn't the so bad since you can get two DPDT relays and then use one elk relay to power both of them (frees up 3 relays on your Elk). These relays can be tiny since the line-level current and voltage is practically nill (which is why humms and pops are a problem. . .signal to noise ratio is like 1 or maybe less than 1). You might look at using telecom relays (telephone switching relays), they are cheap, small, and probably won't introduce clicks and humms. You might even find an old piece of equipment sitting around that has some relays ready for the scavenging.
As far as losing the first few words. I don't know. I would try removing the capacitor and see if it is still there.
As far as losing the first few words. I don't know. I would try removing the capacitor and see if it is still there.
BraveSirRobbin
Moderator
A schematic would go a long way here. 
Also, you are not doing the same thing as I was right (you are doing line level vs. pre-amp level)?
As far as your question:
The other thing you or someone else mentioned is using 10K and 1K resistors instead of 6.8K and 680K. What does that do?
You just want a ten to one ratio with those resistors, which divides the output voltage, thus giving a pre-amp level desired. The 10K and 1K are more common and more people are apt to have them around. You don't want to use to much of a lower value, then you will have current drive issues.
Also, you are not doing the same thing as I was right (you are doing line level vs. pre-amp level)? As far as your question:
The other thing you or someone else mentioned is using 10K and 1K resistors instead of 6.8K and 680K. What does that do?
You just want a ten to one ratio with those resistors, which divides the output voltage, thus giving a pre-amp level desired. The 10K and 1K are more common and more people are apt to have them around. You don't want to use to much of a lower value, then you will have current drive issues.
Allright, figured out the delay - it's due to my wiring. I had two speakers from two keypads wired into output one. Then I connected the line in circuit board setup to + in output 1 and NEG in power. The result was the delay. Line out by itself works. Two speakers by itself works.
Removed the 10 uF capicator, made no difference.
So that solved the delay, now I need to solve the humm and pop. Since I need some way to wire in the two keypad speakers anyways, I think I will use Elk-880 since it can go down to 2 ohms. I am going to use the relays to switch two amplified sources. That should solve the pop and the humm.
Removed the 10 uF capicator, made no difference.
So that solved the delay, now I need to solve the humm and pop. Since I need some way to wire in the two keypad speakers anyways, I think I will use Elk-880 since it can go down to 2 ohms. I am going to use the relays to switch two amplified sources. That should solve the pop and the humm.
apostolakisl
Senior Member
You don't need an amp that can go down to 2 ohms with 2 ohm speakers. Just put the speakers together in series and they will be 4 ohms. Or add a resistor for even more resistance if you like. You can use resistors and putting speakers in series various ways to balance your volume levels without needing multiple amps. For example, put the two keypad speakers in series with a 4 ohm resistor and now you are at 8 ohms. This will also decrease the volume level. Once you get the system balanced, increasing the volume on your amp will make all of them go up but the relative volumes will stay consistent. So I suppose if you want the keypad speakers to always be the same regardless of the other speakers, then you will need a separate amp, but as I mentioned, it doesn't need to be a special 2 ohm amp.
Interesting on the delay.
As far as the humm and pop. The pop is for sure an induced voltage spike in the relay, and it would seem from your experiments that the humm is a similar problem in the relays. I think you just need to use a "quieter" relay and use an elk output to drive that external relay.
Interesting on the delay.
As far as the humm and pop. The pop is for sure an induced voltage spike in the relay, and it would seem from your experiments that the humm is a similar problem in the relays. I think you just need to use a "quieter" relay and use an elk output to drive that external relay.
Thanks for the idea of putting the keypad speakers in series.
The intention of the Elk-800 was to put my maximum 4 ohms from speaker selectors in parallel with the 2x 32ohm keypad speakers, with 3.2 ohms. That's why I was thinking 2 ohms. With the speakers in series I should be at 4 - 11 ohms at the selector, in series with 16 ohms for the 2x 32ohms in paralle, which gives me 20 - 27 ohms of resistance.
It did appear that the pop and humm comes from interference introduced into the elk line level output from the relay switches. So I hypothesized that switching an amplified output instead of line level input with the relays might solve the issue. When I thought about it more, turns out I don't even need the Elk-800. I took my Denon amp, used the main zone to amplify my Sonos line in source, and used zone 3 to amplify my Elk line in source. I wired in the 2x Elk speakers in series with the negative side of zone 3.
The verdict: no delay in speech from elk, no pop and humm when switching! It works!
THANK YOU VERY MUCH FOR ALL YOUR HELP!
The intention of the Elk-800 was to put my maximum 4 ohms from speaker selectors in parallel with the 2x 32ohm keypad speakers, with 3.2 ohms. That's why I was thinking 2 ohms. With the speakers in series I should be at 4 - 11 ohms at the selector, in series with 16 ohms for the 2x 32ohms in paralle, which gives me 20 - 27 ohms of resistance.
It did appear that the pop and humm comes from interference introduced into the elk line level output from the relay switches. So I hypothesized that switching an amplified output instead of line level input with the relays might solve the issue. When I thought about it more, turns out I don't even need the Elk-800. I took my Denon amp, used the main zone to amplify my Sonos line in source, and used zone 3 to amplify my Elk line in source. I wired in the 2x Elk speakers in series with the negative side of zone 3.
The verdict: no delay in speech from elk, no pop and humm when switching! It works!
THANK YOU VERY MUCH FOR ALL YOUR HELP!
apostolakisl
Senior Member
Great to hear.
Using a separate amp for your Elk voice does mean that the volume level won't necessarily match up with the volume of the music. You may or may not care, but it is a consideration.
The humm and pop are still there, but since there is no amplifier after the humm and pop are introduced, they are very quiet, probably you could hear it if you put your ear right up to the speaker, but who cares right?
Using a separate amp for your Elk voice does mean that the volume level won't necessarily match up with the volume of the music. You may or may not care, but it is a consideration.
The humm and pop are still there, but since there is no amplifier after the humm and pop are introduced, they are very quiet, probably you could hear it if you put your ear right up to the speaker, but who cares right?
One more thing I thought of.
I have used up all 16 outputs for my setup now, 2 outputs for each room (6 total) plus 4 outputs for the source switching. When I need more outputs, I believe I can put an elk 924 dpdt relay controlled by one of the relays on the m1xvor or m1rb. How do I connect the relay with the elk 924?
Thanks!
I have used up all 16 outputs for my setup now, 2 outputs for each room (6 total) plus 4 outputs for the source switching. When I need more outputs, I believe I can put an elk 924 dpdt relay controlled by one of the relays on the m1xvor or m1rb. How do I connect the relay with the elk 924?
Thanks!
tmbrown97
Senior Member
I'm not quite sure what you're asking here... there's a lot of options for adding relays to an M1. Onboard there is Output 3 which is a relay, then 10 voltage-only contacts. You can hook an M1RB to that and turn 8 of those into relays; the last 2 outputs you can hook up any individual relays.
Then for add-ons, you have M1XOVR and M1RB. The M1XOVR adds 8 relays and 8 voltage-outputs; pair that with an M1RB and you now have 16 full relays.
You can keep adding from there...
To add an Elk 924 relay you need to trigger voltage to it and hook it to power; it can be any of the voltage-only relays by hooking ground to ground and positive to the output; when the output is on, it'll activate the relay.
Now if you want to hook an Elk924 to an existing relay, you need to hook that relay so it's sending/switching either positive or ground - ultimately you need to get power to it.
For your situation, if it were me, I'd be using either the onboard voltage outputs or an M1XOVR with the 8 relays and 8 voltage outputs - skip the M1RB and instead hook those outputs to a few Elk924's - thereby getting you 2 relays per output - and letting each single output be a complete zone. Those are sold individually or in 4-packs scored to be broken apart; get 2 4-packs and you have a nice compact bank of relays.
If all that didn't cover what you were asking, please elaborate.
Then for add-ons, you have M1XOVR and M1RB. The M1XOVR adds 8 relays and 8 voltage-outputs; pair that with an M1RB and you now have 16 full relays.
You can keep adding from there...
To add an Elk 924 relay you need to trigger voltage to it and hook it to power; it can be any of the voltage-only relays by hooking ground to ground and positive to the output; when the output is on, it'll activate the relay.
Now if you want to hook an Elk924 to an existing relay, you need to hook that relay so it's sending/switching either positive or ground - ultimately you need to get power to it.
For your situation, if it were me, I'd be using either the onboard voltage outputs or an M1XOVR with the 8 relays and 8 voltage outputs - skip the M1RB and instead hook those outputs to a few Elk924's - thereby getting you 2 relays per output - and letting each single output be a complete zone. Those are sold individually or in 4-packs scored to be broken apart; get 2 4-packs and you have a nice compact bank of relays.
If all that didn't cover what you were asking, please elaborate.
apostolakisl
Senior Member
You could use one Elk m1rb relay to power 2 of the dpdt for your source switching between the Elk voice and music. Run a voltage source to the common spot on the Elk m1rb. Run a wire from the NO terminal on the M1RB to the positive coil terminal on the 924's (split the wire). Splice two more wires together from each of the coil commons on the 924 and connect to the common on your voltage source (the auxillary voltage from the Elk board is 12vdc so if the 924 uses 12 vdc then you can use that)
This will free up 3 relays on your Elk m1rb board for the cost of 2 924's. Or, if you found a quad throw dual pole relay you could use that instead of 2 of the 924's reducing the clutter.
This will free up 3 relays on your Elk m1rb board for the cost of 2 924's. Or, if you found a quad throw dual pole relay you could use that instead of 2 of the 924's reducing the clutter.
