No hifi, but still 2 channel.... I am looking for a relatively inexpensive solution to a quirky problem. We replaced our security system and failed to consider how the audio events would work through our automation system. We have touch panels at each door and a wired balanced stereo audio feed goes to the touch panel and you hear the audio when you open an armed door or arm the system.
The new panel (Elk M1 Gold) panel has an unbalanced mono output for siren, and a unbalanced mono output for voice feedback. The prior system combined these two signals into an unbalanced mono out and life was great. I jumped the negative and the ground on both channels (if that is relevant).
ISSUE: Audio from the siren feed (the countdown beeps) is almost inaudible. The voice feedback (system is armed) is overdriven.
QUESTION: Assuming this is an amplified signal, is there an inexpensive way to amplify the siren feed? The security panel offers a variable audio level for voice, but siren level seems to be fixed.
Added data point... there is a simple speaker that came with the new panel and when connected to either siren or voice, things sound fine, but the panel is too far away from any of the doors to be useful from that location.
Any suggestions?
The new panel (Elk M1 Gold) panel has an unbalanced mono output for siren, and a unbalanced mono output for voice feedback. The prior system combined these two signals into an unbalanced mono out and life was great. I jumped the negative and the ground on both channels (if that is relevant).
ISSUE: Audio from the siren feed (the countdown beeps) is almost inaudible. The voice feedback (system is armed) is overdriven.
QUESTION: Assuming this is an amplified signal, is there an inexpensive way to amplify the siren feed? The security panel offers a variable audio level for voice, but siren level seems to be fixed.
Added data point... there is a simple speaker that came with the new panel and when connected to either siren or voice, things sound fine, but the panel is too far away from any of the doors to be useful from that location.
Any suggestions?
>there is a simple speaker that came with the new panel and when connected to either siren or voice, things sound fine.
Un-jump the connections you made. Connect the "simple speaker" across the siren (+) and the voice (+).
Why would this work?
- Siren and voice arent active simultaneously. The one that's not making a signal is at a ground level (0V) or has a reasonably low impedance to ground. So when siren is active, voice is at a virtual ground and vice-versa.
You can do this with a stereo amplifier also. What plays on the right channel only, ...will come out a speaker connected in this way, same as material on the left channel only. What's on both channels simultaneously wont come out. What's phase-shifted between channels will come out in proportion to the shift; if it's 180, it'd be like a bridged amplifier.
Now this assume a normal amplifier topology. Class D, with its ability to go open circuit when not being used, or when there's no signal, wrecks the idea. Try it an see.
Un-jump the connections you made. Connect the "simple speaker" across the siren (+) and the voice (+).
Why would this work?
- Siren and voice arent active simultaneously. The one that's not making a signal is at a ground level (0V) or has a reasonably low impedance to ground. So when siren is active, voice is at a virtual ground and vice-versa.
You can do this with a stereo amplifier also. What plays on the right channel only, ...will come out a speaker connected in this way, same as material on the left channel only. What's on both channels simultaneously wont come out. What's phase-shifted between channels will come out in proportion to the shift; if it's 180, it'd be like a bridged amplifier.
Now this assume a normal amplifier topology. Class D, with its ability to go open circuit when not being used, or when there's no signal, wrecks the idea. Try it an see.
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jjasniew - I may need to draw up a schematic to best explain the current wiring topology. A few more descriptive words would have possibly made it more clear, but your proposed solution may still work great.
Security panel has 4 phoenix terminal posts:
Speaker +
Speaker -
Voice -
Voice +
Touch Panel interface box has balanced phoenix:
Left + (to siren +)
Left - (to siren -)
| (jumpered)
Left Ground
Right + (to voice +)
Right - (to voice -)
| (jumpered)
Right Ground
Question 1 - should I remove the ground to negative jumpers on the touch panel balanced audio input?
Question 2 - based on what you described as the test, should I
siren + (to "simple speaker" +)
siren - (open)
voice - (open)
voice + (to "simple speaker" -)
Question 3 -
If the above test works, then replicate in the full chain by connecting:
siren + (to touch panel left audio +)
siren - (open)
voice - (open)
voice + (to touch panel left audio -)
Security panel has 4 phoenix terminal posts:
Speaker +
Speaker -
Voice -
Voice +
Touch Panel interface box has balanced phoenix:
Left + (to siren +)
Left - (to siren -)
| (jumpered)
Left Ground
Right + (to voice +)
Right - (to voice -)
| (jumpered)
Right Ground
Question 1 - should I remove the ground to negative jumpers on the touch panel balanced audio input?
Question 2 - based on what you described as the test, should I
siren + (to "simple speaker" +)
siren - (open)
voice - (open)
voice + (to "simple speaker" -)
Question 3 -
If the above test works, then replicate in the full chain by connecting:
siren + (to touch panel left audio +)
siren - (open)
voice - (open)
voice + (to touch panel left audio -)
I attempted the wiring suggestions above and it did not improve or change the performance.
I purchased an Audioplex Model 50-6696 300 Watt Stereo to Mono Speaker Level converter, and this too did not change anything.
Ultimately, my issue was resolved by only wiring to the voice feedback output and leveraging options within their software to create additional sounds for the exit/entry process.
I purchased an Audioplex Model 50-6696 300 Watt Stereo to Mono Speaker Level converter, and this too did not change anything.
Ultimately, my issue was resolved by only wiring to the voice feedback output and leveraging options within their software to create additional sounds for the exit/entry process.