Bose F1 Model 812 No Sound Issue

Hi. I work at a church, and I've been appointed a position to handle the media portion of our services. Ever since COVID vaccines have been given out to the public and churches started opening up for face-to-face worship, we decided to pull out our Bose F1 Model 812's from storage.

This is our setup:
- Bose F1 Model 812 (Just speakers, no subs (We have the subs, but we're trying to be as portable as possible. Since we're renting out spaces.)
- Yamaha MG16XU Mixer

So this past Sunday, we hooked up XLR cables from Stereo Out to the Left & Right speakers. Plugged in the XLR for microphone to Line 5, turned the channel "on", but nothing... We tried inserting RCA to 3.5mm to Line 15/16 and playing music from a smartphone. The monitor/equalizer on the mixer, showed green lights going up and down, but still no sound... We tried then, by connecting the smartphone directly to the speaker via TRS to 3.5mm and it played the music from the smartphone.

Does this mean our mixer is fried? It was working fine the week before when we operated YouTube Live out of a office space. We've changed the selectors on the back of the F1 - Front LED > Power, EQ > Full Range, Signal Input > Line Level (I tried changing the Signal Input to Mic and I just got a loud buzzing noise). No dice.

*Apologies for the long explanation. I'm new to all this. I'm more of a "setting up" guy, than a "technical" guy.* All answers will be appreciated, while holding back on any negative feedback/answers please. Thank you in advance!



Hello mister_dub,


I think the problem is definitely with your mixer, since you get sound when connected directly to the F1.  I wouldn't necessarily say that its "fried", but more likely that your signals are just not getting routed to your main outputs.  (I volunteer at our church as one of the sound techs, and sometimes it's an adventure every Sunday to see what settings may have changed from other fingers during the week!)


I have to be away from my computer today, so I can't go into all your mixer's settings at this time.  If there is someone else knowledgeable with the mixer, or a local music shop where to can take the mixer to try with other speakers, you might avail yourself of their expertise (sometimes a second set of eyes is all you need!)


I'll check back tonight.



Thank you for your input, Mr. 'Fish-54'!
I'll maybe have to advise my church leadership to take it to a shop or just buy a new one.
Yeah, I think during transport, my hands/arm may have pressed a simple button that shouldn't have been pressed. Any other knowledgeable person or yourself, when you have time, could maybe look at a picture of the Yamaha MG16XU and tell me what knobs/buttons should be 'on' in order to get the speakers to work. I don't go back out to church until the weekend, so you can definitely take your time!

Hello mister_dub,


I looked at the online manual for your mixer.  In a nutshell:

  • Hook up your mic and/or smartphone to the channels as you did before.
  • Make sure the "ON" button and "ST" button above the channel fader (volume control) for each channel you are using is pressed.
  • Make sure the 1-2 and 3-4 buttons are NOT pressed.  (see note below)
  • Make sure the Master volume fader is pulled all the way down to zero.
  • Make sure the "Stereo Master "ON" button above the Stereo Master fader (far right side of the mixer) is pressed.
  • Talk into your mic and/or play music from your smartphone.
  • Raise the Master fader to send a signal to your main outputs.  You should be getting sound.

Note:  The 1-2 and 3-4 buttons are only used if you are sending some inputs (like all mics) to one "subgroup" and other inputs (like all instruments) to the other "subgroup".  The advantage to doing this is the ability to change the volume for everything in the subgroup by using only one control (the "Group 1-2" or Group 3-4" faders.)  In this case, you would assign a channel to 1-2 or 3-4 and UNselect the "ST" button.


Does that help?

Woooo~ Lots of great information! I shall and test it out this coming Saturday, when I go and setup for Sunday's service. After I do all that, and it still doesn't work, then new mixer it is! Thank you so much for your detailed response and taking the time to look at the overall function of the mixer we have. I'll write a reply once I've tried it out!

Hello mister_dub,


One thing I forgot to mention -- be sure to set the input level switch on the rear of the F812's back to "line level" instead of "mic".  That's the reason you got the buzzing -- mic level is much more sensitive to any electrical interference, and is very quick to overdrive if you send the mixer's line-level signal.


p.s., do you have a "Plan B" in case your Saturday night test isn't successful?

Thank you, Mr. Fish-54! 😁

I went to church today, in the early morning and went step-by-step as you said.
For some reason, the 1-2 & 3-4 button were pressed. Like you had mentioned "subgroup". I think it's because initially when our church was only doing YouTube Live in an office space. We had a USB input in the back connected to a CD player for ambient music and a bluetooth receiver for our keyboard/piano. So in order to change all the devices (mic, keyboard, cd player) at once, I think that's why we had 1-2 & 3-4 selected.

But after I depressed 1-2 & 3-4, BAM! That did the trick!

And answer to your other post "Do you have a backup plan in case it's not successful?" Yes, we have a Roland indoor/outdoor PA speaker that we can hook up the microphone directly to, and just use that as a backup in case of an emergency. Such as last week on Sunday, when our mixer wouldn't output any sound to the Bose, we had to get our Roland PA and have service like that. But obviously, it wasn't loud enough, therefore it was a bit of a pain in the rear. But nonetheless, God is good! You've definitely saved my church from making a useless purchase for a troubleshoot that was so very simple. Thank you again! Blessings!