Webcasting Voice Backup

What are you using for backup devices to get building sound to a std phone conference call-in connection?

We have webcasting down but no backup. Considering a
CHAT 50 USB Plus Personal Speaker Phone device. The church techs use it for doing the brethren's webcasts.

Any experience with it?

If I remember correctly, the crab box that has a pair of RJ11 telephone jacks on the side can do both directions to/from the phone line. (There are two types of crab boxes: one with phone jacks and one without.) I understand there should be at least one of the with-phone-jack crab boxes in each stake, and that the instructions describe how to set up the path from a record output or other output from the PA system to the box to get sound out over the phone.

Around 35 years ago, when I was in high school, at the request of local leaders, I helped arrange for a general conference priesthood session over the phone to a homebound elderly brother. I hung a carbon microphone element (similar to the kind used in telephones of that era) near the foyer loudspeaker and ran a pair of wires from the mike to the handset receiver in a clerk's office. That setup is low-tech by today's standards, but I understand it worked fairly well.

Crab Box

The link includes links instructions and pictures of what they look like. Clearly it's not "dial in". It requires manual operation.

As an update to this I spoke directly with the company who makes the "crab" boxes. They said that if you want to inject audio into a phone line this is what you should use:

http://www.emtechelectronics.com/produc ... ters/ej-r/

It's around $55 with Church pricing. I mentioned the EJ-10 but got the impression it either won't work for this or does a less than ideal job. In any case, this device is inexpensive and purpose made so we have one on the way.

ldsrussp wrote:It's around $55 with Church pricing. I mentioned the EJ-10 but got the impression it either won't work for this or does a less than ideal job. In any case, this device is inexpensive and purpose made so we have one on the way.

I used an EJ-10 on Saturday and Sunday (as audio backup for the webcast of a YSA fireside and Stake Meeting with Elder Richard G. Scott). It required headphone level audio coming off of the board to get decent audio volume out into the telephone line.

Aaron Z

The EJ-R is the way to go for the originating side. The EJ-10 works great on the receive side. If you don't have an EJ-10 (grey zipper case) on the receive side (and have an EJ-8, black zipper case) you can get an TTAI (same manufacturer) to receive the phone line and prepare to inject it into the PA if you have an Internet failure. My understanding is that all of these devices are order-able through your FM and should be at his cost, not the stake's.
Troy

Good point on the cost. FM group might pay for it. I'll see about that once it arrives.

Is the EJ-R on the FM Group purchase list? I asked our FM Group about purchasing the EJ-R and they said no!

behjah wrote:Is the EJ-R on the FM Group purchase list? I asked our FM Group about purchasing the EJ-R and they said no!

Ours just bought one for the Stake Center. Cute little box.

Aaron Z

Our stake purchased a Symentrix TI-101 hybrid telephone interfacefor $80 and permanantly wired it in our audio rack, so all we need to do is call the phone number of the conference bridge and turn up the gain. This is a professional broadcast unit for radio station call-ins and conferencing. Since the unit has been discontinued, many radio stations are dumping them on the market.

We just did our webcast yesterday for Stake Conference. As audio backup we had someone in our satellite room at the Stake Center with a smartphone capable of conference calling. The satellite room has audio piped into it with a speaker and volume control. At all the other buildings we just had one person call in from each location and added them to the conference call in the satellite equipment room. The phone picked up the audio well from the speaker and all others could hear fine. Our webcast was being received with laptops at the various buildings and they were plugged into the sound system using the crab unit with a mini-jack to the headphone port on the laptop. If the webcast failed all they need do was unplug the audio cable from the computer and plug it into the headphone jack of their phone. Quick and painless. We just kept the conference call going the whole broadcast. Hint: Make sure everyone uses their chargers. We tested and it worked great but thankfully the audio backup was not needed yesterday.

The low-cost method is to simply bridge the audio output from the PA system into the multiple EJ-10s with passive cable splitters or equivalent. That will work well if the input impedance of the EJ-10 is much higher than the output impedance from the sound system.

The higher-cost and higher-quality solution is to use an audio distribution amplifier similar to the ones inside the rack. If you're handy at constructing homebrew audio gear, just throw a few op-amps, some Rs and Cs, and a power supply together and it will probably work flawlessly. Otherwise, there are units available commercially that would work.

rmrichesjr wrote:That will work well if the input impedance of the EJ-10 is much higher than the output impedance from the sound system.

This was discussed in this thread, the input impedance is actually quite low. I'd say it's lower then I'd like connect to professional line-level equipment.

I haven't tried it, but if it were me, I'd go find a small speaker amp and use that. A speaker amp would have no problem driving 3 EJ-10s (about 83 ohms). It would also allow you to compensate for the loss in the box.

wxrwxr wrote:ON the Audio backup solutions for Church broadcasts page instructions are given for using the EJ-10 at both the receiving and transmitting ends. But if the transmitting end is to transmit to more than one building additional instructions are needed. Suppose 3 receiving buildings are to be in the conference. The transmitting end would need three telephone lines and three EJ-10s. But how do you get the audio from the sound system's output into three EJ-10s at the same time?

What we do as backup for the webcast is to use an audio conference bridge as described on the wiki: https://tech.lds.org/wiki/Audio_confere ... nghouse%29

Then we only need one EJ10 in each building and we only tie up one phone line in each building.
Edit: I believe that is also used for High Council and other Stake meetings with far flung participants.

Aaron Z

RussellHltn wrote:This was discussed in this thread, the input impedance is actually quite low. I'd say it's lower then I'd like connect to professional line-level equipment.

I haven't tried it, but if it were me, I'd go find a small speaker amp and use that. A speaker amp would have no problem driving 3 EJ-10s (about 83 ohms). It would also allow you to compensate for the loss in the box.

A small speaker amp would be a good option to consider, but I think I'd want to plan on a suitable attenuator between the speaker amp and the EJ-10 to avoid any possibility of overdriving it (damage to the EJ-10 not very likely but not entirely unthinkable), to attenuate the likely higher-than-line-level noise on the speaker output, and to allow the speaker amp to produce enough output to be well out of the range where crossover distortion would be a problem.

My reading of the referenced thread says the line input impedance of the EJ-8/10 is 4.9k at 1kHz. If that is accurate, bridging three of that load would be 1633 Ohms, which would be entirely reasonable for a good line-level output. The PDF schematic does not state the impedance of the transformer, which could make a big difference.

rmrichesjr wrote:A small speaker amp would be a good option to consider, but I think I'd want to plan on a suitable attenuator between the speaker amp and the EJ-10 to avoid any possibility of overdriving it (damage to the EJ-10 not very likely but not entirely unthinkable), to attenuate the likely higher-than-line-level noise on the speaker output, and to allow the speaker amp to produce enough output to be well out of the range where crossover distortion would be a problem.

Optimal, but I doubt if it's necessary. (I've seen people connect speaker outputs to mic input )

rmrichesjr wrote:My reading of the referenced thread says the line input impedance of the EJ-8/10 is 4.9k at 1kHz.

That's sounds about right for the line-level inputs on the top of the box, but not the special input on the side that's for feeding the phone line. At best, it's a few hundred ohms.

BTW, you might want to read this thread which has a EJ-10 schematic. What you'll see is the "Audio input" has a 100 ohm resistor in series with a 10 ohm resistor to ground. Therefore the impedance has to be somewhere between 100 and 110 ohms. Not exactly "line level friendly".

rmrichesjr wrote:A small speaker amp would be a good option to consider, but I think I'd want to plan on a suitable attenuator between the speaker amp and the EJ-10 to avoid any possibility of overdriving it (damage to the EJ-10 not very likely but not entirely unthinkable), to attenuate the likely higher-than-line-level noise on the speaker output, and to allow the speaker amp to produce enough output to be well out of the range where crossover distortion would be a problem.
My reading of the referenced thread says the line input impedance of the EJ-8/10 is 4.9k at 1kHz. If that is accurate, bridging three of that load would be 1633 Ohms, which would be entirely reasonable for a good line-level output. The PDF schematic does not state the impedance of the transformer, which could make a big difference.

What if one used a headphone amp? You can get one with 1 in to 4 (separately controlled) outputs for $20.
That should take care of the volume differences needed and in my experience, headphone level output just loud enough (or at least the headphone output on my SCM-800 gives a nice level into the EJ-10).

Aaron Z

Aczlan wrote:What if one used a headphone amp?

That may work. It probably depends on the amp.

Aczlan wrote:What if one used a headphone amp? You can get one with 1 in to 4 (separately controlled) outputs for $20.
That should take care of the volume differences needed and in my experience, headphone level output just loud enough (or at least the headphone output on my SCM-800 gives a nice level into the EJ-10).

Aaron Z

If the $20 headphone amp has variable gain, maybe +/- 10 or 20 dB, I would think it should work. At that price, there's not much to lose by trying it. I suspect the SCM-800 is NOT the one with the $20 price tag.

Even if the $20 amp does not have variable gain, it could very well be sufficient, especially as a backup channel.

rmrichesjr wrote:If the $20 headphone amp has variable gain, maybe +/- 10 or 20 dB, I would think it should work. At that price, there's not much to lose by trying it. Even if the $20 amp does not have variable gain, it could very well be sufficient, especially as a backup channel.

I agree

I suspect the SCM-800 is NOT the one with the $20 price tag.

No it is not (the $20 one is a Behringer HA-400 from B&H) , but I had the SCM-800 in the rack with my main mixer (a Mackie VLZ1402PRO) from when I was mixing for an area leadership training meeting in Feb and I needed something to increase the volume for the phone line without distorting the sound like the "computer speaker" headphone out did.

Aaron Z

Aczlan wrote:What we do as backup for the webcast is to use an audio conference bridge as described on the wiki: https://tech.lds.org/wiki/Audio_confere ... nghouse%29

Then we only need one EJ10 in each building and we only tie up one phone line in each building.
Edit: I believe that is also used for High Council and other Stake meetings with far flung participants.

Aaron Z

We just tested this out using the Verizon conferencing line that the church will setup for you. The problem we found is that the audio was very low and would cut out a lot. We took the conference line out of the mix and called a line directly and the audio stopped cutting out as much, but the sound was still very soft.

Has anyone else had this problem? How did you resolve it?

Thanks
Bryson

bshepher wrote:Has anyone else had this problem? How did you resolve it?

How were you getting audio into the telephone line? The EJ-10 needs a strong signal. See the prior discussion in this thread.

bshepher wrote:We just tested this out using the Verizon conferencing line that the church will setup for you. The problem we found is that the audio was very low and would cut out a lot. We took the conference line out of the mix and called a line directly and the audio stopped cutting out as much, but the sound was still very soft.
Has anyone else had this problem? How did you resolve it?

As I said above, I ran headphone level audio into the line in port on the EJ10. That worked fairly well.

Aaron Z

We bought a Rolls PhonePatch II - http://www.rolls.com/product.php?pid=PI9 - it was $40.

Since we use a mixer to mix the webcast audio, we just have an auxiliary output on the sound board which feeds the audio for the phone line.

bshepher wrote:We just tested this out using the Verizon conferencing line that the church will setup for you. The problem we found is that the audio was very low and would cut out a lot. We took the conference line out of the mix and called a line directly and the audio stopped cutting out as much, but the sound was still very soft.

Has anyone else had this problem? How did you resolve it?

Thanks
Bryson

There have been times when we needed to use our EJ10 for some purpose other than audio backup, immediately before, after or during a webcast. We followed Troy's recommendation in this post earlier in this thread and asked our FM group for dedicated Emtech devices. In preparation for our recent Stake Conference, we requested and received an EJ-R to use to inject the audio into our phone conference bridge and a TTAIB for each receiving location. This solution worked very well during our testing.

Useful information if you decide to go with this solution:

1. Our FM group initially couldn't find these Emtech devices in their ordering system. Tell your FM person that they need to place the order through the Church MTS Department.
2. These Emtech devices are designed to be installed between your telephone handset and the telephone base. Some phones are not compatible with these devices, so if it doesn't work when you test, try a different phone. Also, Princess type phones, with the buttons in the handset, will not work at all. Use a classic phone that has the buttons in the base.

We bought a Rolls PhonePatch II

I just wanted to confirm this was for sending audio over the phone line, and not receiving it? Did you have any problems with distortion using this device (its instructions caution against using a hotter-than-line input).

danpass wrote:In preparation for our recent Stake Conference, we requested and received an EJ-R to use to inject the audio into our phone conference bridge

How loud did the signal going into your EJ-R need to be? In our experience, it needs to be loud headphone level, but that seems odd to me.
What has your experience been?

Aaron Z

Aczlan wrote:How loud did the signal going into your EJ-R need to be? In our experience, it needs to be loud headphone level, but that seems odd to me.
What has your experience been?

Aaron Z

I got the audio input signal from the same line level source that feeds into our Webcast Communicator. I used an adapter cable with an RCA connector on one end and 1/4" headphone plug on the other. The sound level was good at the receiving locations.

danpass wrote: Useful information if you decide to go with this solution:

1. Our FM group initially couldn't find these Emtech devices in their ordering system. Tell your FM person that they need to place the order through the Church MTS Department.
2. These Emtech devices are designed to be installed between your telephone handset and the telephone base. Some phones are not compatible with these devices, so if it doesn't work when you test, try a different phone. Also, Princess type phones, with the buttons in the handset, will not work at all. Use a classic phone that has the buttons in the base.

Our stake is hosting a fireside tomorrow evening with a member of the Seventy. I was asked to Webcast it to outlying stakes in our Coordination Council. It is my first experience with setting up a Webcast. All is in place except the audio backup. The information here and on RKATS has been invaluable.

I obtained the recommended Mackie VLZ3 mixer and Emtech EJ-R and put them in place yesterday. Connected the audio source and called my cell phone from the phone in the satellite closet. No audio, but did get clicking if I unplugged the phono plug and the lights at the lower right of the mixer showed there was sound.

Read the section of the quoted post above and determined the problem was the princess style phone. Went back today and put one of the office phones in the loop instead of the princess phone. Called my cell and again, no audio. Again the lights on the right of the mixer show that there is sound at the mixer.

It was interesting that the handset mic didn't pick up my voice when I talked into it regardless if the mute switch on the EJ-R was set at Mute or Off. If I talked into my cell, I could hear myself in the handset speaker.

The quoted post says not all phones are compatible. I guess now, the theory is that the desk phones in the stake center are the problem. Or can anyone see where I'm not doing something right?

Looking at the EJ-R specs, I notice that it says the input should be a stereo headphone. In that case, if you feed it with balanced audio, you'll get nothing. (Because the "left" and "right" "channel" will be 180 degrees out of phase.) It may or may not work well with a mono (two-wire) connection. Lastly is levels. Make sure the mixer is pumping out closer to 0 VU, not way down -20. And it has to be line/headphone level, not mic level.

Thanks for your quick reply Russell. However, the spec sheet at the Emtech site (http://www.emtechelectronics.com/medias ... /EJR_1.pdf), page 2, Inputs, lists '1/4" Mono Phone Jack'.

Spoke a bit too soon. I looked at the "Manual" link and the specs there do indeed say it is a '1/4" Stereo Phone Jack'. (http://www.emtechelectronics.com/medias ... ctions.pdf)

I probably have a mono so will get a stereo and see if it makes a difference.

jeromer7 wrote:the spec sheet at the Emtech site (http://www.emtechelectronics.com/medias ... /EJR_1.pdf), page 2, Inputs, lists '1/4" Mono Phone Jack'.

I was reading the user manual. It says "stereo". I wish there was a schematic, because then I'd have a better understanding of what could be going on. (Personally, I'd prefer it to be a line-in, balanced or unbalanced. If I have a headphone feed, I'm probably going to want to use it for MY headphones, not as an extra output.)

I do know this: The EJ-R is a passive device. All the power needed to drive the phone line will have to come from the mixing board. That's going to take a strong line level, maybe more (which may explain headphone input). Anything that kills the level could leave you with something too weak to work.

jeromer7 wrote:Called my cell ...

It appears that you are getting to the bottom of your issue with Russell's help.

Your mention of using your cell phone brings to mind another caveat that we discovered in our testing. This has nothing to do with the issue you are experiencing.

In addition to items 1 and 2 in my previous list, I would add:

3. Don’t use a mobile phone on the receiving end of the audio backup.

We webcast our Stake Conferences from our Stake Center to two other meetinghouses. We use the EJ-R to supply the audio feed into a conference bridge. The two remote locations use the TTAIB device to supply the audio from the conference bridge into their respective building sound systems. Once we had phones that were compatible, all our testing of both voice and music over this audio backup solution was successful. We test all of this along with our webcast equipment during the week leading up to each local stake conference.

Prior to a subsequent Stake Conference, during testing, one of the remote sites reported that while the organ was being played, the backup audio kept cutting in and out on their end. Regretfully, we didn't determine the cause of this problem until after a problem plagued webcast of a Stake Priesthood meeting months later.

My A/V assistants in that building had begun using their cell phones to call into the conference bridge, rather than the phone and landline connection which we had installed in the chapel for this purpose. When I found this out, I asked them to switch back to using the landline. This eliminated the problem.

Until we figured this out, they had both tried different cell phones (IOS and Android), on different carriers, as well as patching them into both the TTAIB as well as their crab box. In all cases, the audio would start cutting in and out whenever organ music began.

danpass wrote:Your mention of using your cell phone brings to mind another caveat that we discovered in our testing.

Two thoughts come to mind:

The vocoder (the software that digitizes the sound) is tuned for voice, not music. That can make some things like music sound really, really bad.

The second is that I've observed that there's some kind of echo canceling, or other processing that may mute a weak signal if there's too much background noise at your end.

russellhltn wrote:

jeromer7 wrote:the spec sheet at the Emtech site (http://www.emtechelectronics.com/medias ... /EJR_1.pdf), page 2, Inputs, lists '1/4" Mono Phone Jack'.

I was reading the user manual. It says "stereo". I wish there was a schematic, because then I'd have a better understanding of what could be going on. (Personally, I'd prefer it to be a line-in, balanced or unbalanced. If I have a headphone feed, I'm probably going to want to use it for MY headphones, not as an extra output.)

I do know this: The EJ-R is a passive device. All the power needed to drive the phone line will have to come from the mixing board. That's going to take a strong line level, maybe more (which may explain headphone input). Anything that kills the level could leave you with something too weak to work.

If a schematic would still be helpful, there's a hand-drawn schematic someone else posted in 2010 in a thread titled "Care and feeding of the EJ10". Here's the URL to the schematic: https://tech.lds.org/forum/download/file.php?id=719

I'll second (or third or ...) the advice earlier in this thread to use plain, passive landline phone rather than cell phone. In fact, you can likely hang up the phone once the connection is made. The crab box's telephone circuit has low enough resistance it should keep the phone call active. That should give you better SNR and better levels. If you do that, there will be a loud click and a change in level when you hang up the phone.

Another suggestion would be to 'Y' the headphone output from the mixer to feed both your headphones and the crab box. The mixer's headhone output should have low enough output impedance to feed both.

HTH

rmrichesjr wrote:If a schematic would still be helpful, there's a hand-drawn schematic someone else posted in 2010 in a thread titled "Care and feeding of the EJ10". Here's the URL to the schematic: https://tech.lds.org/forum/download/file.php?id=719

That's the "10". We need the "R".

russellhltn wrote:That's the "10". We need the "R".

Ahhh, I didn't look closely enough at the picture on the spec sheet. Sorry for that error.

I'm a little surprised to see the tap done on the RJ-6 connection between the base and handset. There is not much standardization in the wiring of that connection, in contrast to the very well standardized RJ-8 line between base and switching equipment. Most headsets I have used on the RJ-6 connection have a big switch with at least six positions to handle various standards, and there are still some combinations of phones and headsets that can't be made to work together.

Still, I would be fairly confident that the non-telephone side of the EJ-R has essentially the same circuitry as the path between telephone RJ-8 and line-level input on the EJ-10. If there is still time to test potential solutions, I'd try that hypothesis if it were me. IIRC, standard telephone levels are +8 or +12dB above 1mW into 600 ohms. That would be on the order of 2-3 volts of signal. That's considerably higher than most consumer-grade line-level outputs. I'd favor using a headphone output to drive the EJ-R.

rmrichesjr wrote:IIRC, standard telephone levels are +8 or +12dB above 1mW into 600 ohms. That would be on the order of 2-3 volts of signal. That's considerably higher than most consumer-grade line-level outputs.

Correct. That's about right for pro-grade (XLR) type line outs, but only when running close to 0dB on the VU meter. Add any attenuation, (and the EJ-10 had quite a bit) and it goes down hill from there.

I 'd agree it probably needs something more then just line-out. It needs it's own amp. If you don't mind sparing it, a headphone out would work, but I think I'd be inclined to try and find a small speaker amp for it.

Good discussion. Since the fireside webcast is tonight and I have other work that needs attention today, I am dropping the EJ-R for now and will use a speakerphone dialed in to the audio backup teleconference.

Last night I met with someone who was an audio engineer in a former life. He used headphones and touching the plugs just right was able to hear the audio on the tip of the stereo phone plug coming out of the mixer. But once plugged into the EJ-R we get nothing out on the phone line. We used Main Out as well as the Headphone Out jacks on the mixer.

A weird fact that I mentioned in an earlier post is that the handset mic is off when hooked to the EJ-R. It didn't matter whether the switch on top was in the "Off" or "Mute" position.

jeromer7 wrote:A weird fact that I mentioned in an earlier post is that the handset mic is off when hooked to the EJ-R. It didn't matter whether the switch on top was in the "Off" or "Mute" position.

Ugh. You may be looking at a non-standard handset wiring. If the unit can't mute/unmute, then odds are it doesn't know the right wire pair to inject the audio on. All I can suggest in that case is try another phone or skip the EJ-R and find something else to feed the phone line.

Another thing to consider if the cable being used to connect. Some cables "flip" the signal, some don't. Depending on the wiring, a flip could render something unusable.

I realize this thread is now several years old. However, I am trying to get an audio-only backup solution working in our stake for our webcasts. In the process, I have learned quite a bit so I thought I would share it in case it helps somebody else.

First, there are apparently several editions of the EJ-10 box. Older EJ-10 boxes were designed to take a signal FROM a phone line, but they were NOT adequate to inject a line level signal TO a phone line. I spoke with a rep from Emtech who told me that the older EJ-10 versions had two transformers between the line level signal and the phone line that attenuated the signal too much to be useful.

The newer EJ-10 boxes have been redesigned and should be able to be used on either the sending or receiving sides.

He also mentioned that the Emtech EJ-R boxes were specifically designed to work on the sending side, and are about 1/4 the cost of the EJ-10.

We currently have an EJ-10, but I'm guessing it is one of the "older" versions because it has never been able to provide a strong enough signal for our audio backup solution.

I am requesting an EJ-R from our FM group and will give it a test to see if it works better. I will report back and let you know if #1) the FM group is willing to provide us with the EJ-R, and #2) if the EJ-R works better than the EJ-10 did.

Also, I will try to get more details about how to differentiate between different EJ-10 versions. This could be useful because some of you might already have a newer EJ-10 that will suffice for the sending or receiving sides, but some of you might have an EJ-10 that will only work on the receiving side, and it would be nice to know the difference.

Regards,
Michael

Adding some additional information to my prior post:

It sounds like the EJ-10 boxes that are labeled as coming from the "IWE" company (Industry West Electronics) definitely will not suffice to send a signal over a phone line. Their design only supports receiving a signal. Also, for a period of time after Emtech procured IWE, the EJ-10 was sold with the same design but had an Emtech label on it. The tech support guy from Emtech that I spoke with today said that EJ-10 devices that were sold up until about 2014 or 2015 retained that older design, so they also would not be suitable for sending a signal over a phone line.

There should be an Emtech sticker on the back of the box (where all the cables are strapped on) that has a 4 digit date: MMYY. If the year is before 2015, I would be suspect of that box.

The tech support guy said that after 2015, the EJ-10 box design was changed and that it should suffice for sending over a phone line as well as receiving. He also said that the EJ-R box would provide an even stronger signal. I didn't ask him about that, but I thought it was an interesting statement.

The Help pages for Audio backup on lds.org (https://www.lds.org/help/support/webcas ... s?lang=eng) specifically refer to using an EJ-R for the sending side and an EJ-10 on the receiving side. I have requested an EJ-R from our FM group, and once we have one, I will run some tests and let you know what we find.

I hope this helps!
Michael Smith