Two or More Headsets

Can’t find that this is covered anywhere.

Using latest version of Mira Pro on Ipad Pro . In the house, everything works fine. Talk/listen/respond all good.

The A/C has four Lightspeed Zulu 2s. With only the Pilot headset Bluetooth connected to the Ipad, all works fine like in the house. Connecting the other front seater’s headset to Mira is the next step I desire. Lightspeed tells me that only one Zulu headset can be connected to an external device. If that is the final answer with no other solution, then that person will hear me endlessly saying “Check” and have no idea what is going on. Of course what I want is for them to hear Mira speaking. Is there a solution that allows two or more headsets to all participate?

There currently is not a good solution wirelessly. The limitation is the hardware and bluetooth spec currently implemented. The latest bluetooth spec does accommodate for multi point audio but there has been no great implementation as of yet and would probably require both the device and headsets to support. Apple does support sharing two devices but only if they are AirPods. With Lightspeed there is a potential way to setup if use wires, but in my limited testing it seems like noise over the wires causes some issues and things don’t work as reliably. Not sure if some better shielded cables could solve such a problem. Bose doesn’t support wires at all for the microphone. If you want me to post the wired setup I figured out for Lightspeed I could do that if you want to do some testing.

I have dreamed up a wireless mixing board in my head for multiple bluetooth devices and I have searched far and wide and have not been able to find something like it yet. It may exist in the motor bike world because groups of bikers ride in packs. There are some bluetooth transmitters/receivers that work with multiple devices that may work like this… haven’t found one that also works with the bluetooth mic and a bit wonky with the 3.5mm jack. PS Engineering has an audio panel with two bluetooth radios that does allow multiple headsets to be hooked up and you can switch the audio for pilot, copilot and passengers but that also has an issue with auto-squelch circuitry that chops off the very beginning of words which affects the voice recognition working reliably.

I have thought through another solution where both a pilot and copilot would both have MiraCheck on their device and in real-time over bluetooth when a command is executed it executes on both devices. It is a pretty big investment to pull that off in a reliable way and there just doesn’t seem like the market is there yet for that.

Just like you, it bothers me as well that sharing some audio would be so difficult in 2021.

Thanks greatly for the well thought out response.

Tried out a blue tooth “receiver” with a 3.5 to 2.5 mm adapter plugged into the front panel music jack on my PMA8000B. If my Zulu is not paired to the iPad at all and the extra BT receiver is, then Mira’s speech will go to the 8000B, so both folks can hear it. That is half the battle, you just can’t talk to her. If I then pair my headset, the audio out stops going to the 8000B and goes only to my headset.

Can your SW directly select which BT device(s) get the audio out from Mira?

Unfortunately there is a limitation for bluetooth where you can’t separate the output (speaker) and input (mic). That is what I was talking about that the new spec allows multi point audio where you can do those sort of things. The only thing I could get to work so far is with the Lightspeed they have a cable that you could send into a splitter on the iPad so the mic comes from the headset and the speaker output on the splitter could go to your audio panel. As I was saying the, with that wired setup the performance seemed less than optimal with noise with the cable that came with the Lightspeed.

I am no audio engineer. Maybe there is someone on the forum that would love to solve this challenge.

Two questions on this thread–
-1- Would Mira react incorrectly if the Checklist Item was read back and followed by “Check”? That would allow the Co-Pilot to know what is being done.
-2- Does Mira only like one response to each checklist item, which is “Check”?

Sorry, I don’t understand question #1. You can say CHECK, CHECK ITEM or CHECK IT.

Sorry for lack of clarity. What does Mira do if the reply from the Pilot is to read the Checklist Item and then say “CHECK”. For example: Mira: Fuel on both. Pilot: Fuel on Both -CHECK.

The Co-pilot would then understand what is happening as they would hear the Pilot repeat the Checklist Item followed by “CHECK”. Would Mira get confused by hearing extra words before hearing “Check”?

I understand now. Yes you can repeat the challenge/response and then say CHECK. It is looking for the word CHECK, CHECK ITEM or CHECK IT anywhere in the response.

Mira: Prop, High RPM

OP – “If that is the final answer with no other solution, then that person will hear me endlessly saying “Check” and have no idea what is going on.”

This is the “Other Solution” Reading back the CheckList Item fully solves the problem raised in this thread. Not exactly high tech, but sometimes low tech is the fix.

Have you got an “AUX” option on your radio? If you have then you plug your iPad into an aux plug on your panel and pax hears everything. That’s what I use

Ridgeskimmer, my experience is that, in the case you describe the audio out from iPad does get distributed by the PMA8000B, but mic in comes from the iPad built in mic only and not from the headset. The cockpit environment is too noisy for that to work well. Speaking to Mira has to come from a noise cancelling mic.

You are correct if you are using the voice recognition capability.

I have been experimenting with different audio cable setups to pull something like this off. In theory I have a setup that should work, but in my initial testing, there is something going on with the squelch in my audio panel that seems to cause an issue. If you want to try following this and put a cable like this together it would be good for another audio setup test.

Note: I recorded the following video prior to my initial flight test, which again in my audio setup was less than satisfactory.

Lightspeed over Audio Panel

You can tap on the blue links or related content in the procedure to purchase any component

I tried this today with a Garmin GMA35c audio panel, and the iPad running MiraCheck connected over Bluetooth to the audio panel. Works as well as with the iPad connected to the Bose A20 headset. The audio recording comes from the audio panel, and has low background noise, as is tested not only with MiraCheck, but also with the “Voice Memos” app.

Thank you for your feedback! So you are saying that when you bluetooth your headset directly to the Garmin that you can use the voice commands to control it and all wired headsets in the airplane can hear Mira’s responses? You could then even route the audio from Mira to yourself, you co-pilot and passengers. I have seen issues with auto-squelch which can cutoff off the beginning of commands, but are you confirming the the Garmin GMA35 does a good job at this?

When I connect my iPad (not headset) over Bluetooth to the Garmin GMA35c, I can use the voice commands to control MiraCheck.

Not specifically tested (I was alone during the test), but:

  • I rather strongly expect: Which wired headsets hear Mira’s responses is determined by the routing of the “Bluetooth” audio source in the “Intercom” settings on the GTN750 which remotely controls the GMA35c. So that can be set, as desired, to any combination / non-strict subset of pilot, copilot and passengers, including all.
  • Which headsets can give voice commands is most probably determined by the same routing/setting. If not, I strongly expect at least the pilot and copilot can.

In my limited test on the ground, but while the engine was running at an as high setting as I could safely set it to while holding brakes with my head down, I didn’t notice any issue around auto-squelch.

Thank you for the info! Sorry, yes I meant to ask when you bluetooth the iPad to the Garmin instead of directly to the headset as you stated in your previous post.

I know PS Engineering audio panels are popular as well.

If someone has a PS Engineering PMA450B, would love to understand if it performs equally as well as the Garmin by doing the same test.

MiraCheck works fine with my iPad and one Lightspeed PFX headset connected by bluetooth. But like others, I would like to have both Mira’s voice and my responses heard on other headsets, particularly the co-pilot’s headset for training purposes. One work-around is to use a pair of wired (or bluetooth) earbuds, with the pilot and co-pilot each having just one earbud and wearing the aircraft headsets over the earbuds. Most earbuds are small enough that there is no problem wearing the aircraft headset over the earbuds. The PIC should have the earbud with the microphone if only one earbud has a mic. Klutzy, I know, but it works. One advantage of this option is that if you have an electrical failure, at least you still have your MiraCheck available for Emergency use, which would not be the case if you’re connected through the panel with a Garmin GMA35C or some other method.

I have also tried connecting the iPad to the Garmin GMA35C. Unfortunately, my experience was not the same as Imamane’s. In my airplane, when the iPad is BT connected to the GMA35C, MiraCheck works fine when it first loads up, and I can hear Mira’s voice on all headsets. However, when I activate the microphone on MiraCheck (either by setting the “Talk to Mira” switch on or by touching the microphone icon on the checklist page), Mira does not pick up my “Check” responses or any other commands spoken into any of the headset microphones. This is true whether I am using just one or multiple headsets. Further, as soon as I activate the microphone function on MiraCheck, then I can no longer even hear Mira’s voice in any headset! Everything has gone silent.

As a work-around, I can use MiraCheck connected to the Garmin GMA35C if I simply leave the Talk to Mira microphone turned off and manually check each item, either with or without the Big Check Overlay. At least, in this way the co-pilot can hear Mira’s voice and see that I have checked off each item.

Interesting. Are you saying by putting an AirPod inside the ear-cup, the mic on the AirPod works well enough to pick up commands that are being spoke into the headset? You typically can hear yourself in the ear-cup as you talk if connected to the intercom, but I wouldn’t imagine the volume would be loud enough for the AirPod to pick up on.

Good point. Your probably correct. I haven’t actually tried it with the wireless earbuds like AirPod, but it works fine with wired earbuds plugged into the iPad.

There are wireless earbuds, such as the TECNO-Bravo-B1 ($24.99 on Amazon), that have a separate microphone not built into the earpod itself. I expect those would work just as well as the wired earbuds when paired to the iPad.

Also, with respect to my earlier post, I failed to mention that my Lightspeed PFX headsets are getting their power from the panel with LEMO connectors, so the BT connection of the Lightspeed PFX to the iPad would not work in the event of a total electrical failure. Of course MiraCheck would still work fine I expect with wired earbuds or wireless like the TECNO earbuds connected to the iPad.

  1. Try just using a recording app (e.g. “Voice Memos”) to debug the problem.
  2. In the Bluetooth settings of your iPad, press the ⓘ next to the GMA’s bluetooth name. What do you have under “Device Type”? I have “Car Stereo”.