A couple of months ago I had the idea to see if there was a simple way to play iTunes music from the built-in iMac speakers while also playing it through a Bluetooth speaker (in this case a JBL speaker). My goal was to have the music playing from the computer in one room and also playing from a Bluetooth speaker in the dining room. Sure enough, OS X has a way to do this (I’m running 10.9 so I don’t know how widely this feature is supported across older versions of OS X).
Thanks to user Eric Ross in the Apple Support Communities I didn’t have to do much searching to find the answer. As detailed in his response, the solution is to open the Audio Midi Setup application located in the Utilities folder and then simply create a Multi-Output Device that has both speaker types selected. Note that in order for this to work the Bluetooth speaker needs to already be connected to the Mac.
At this point we’ve only created the multi-output device. One additional step is required – setting it as the current output device (System Preferences -> Sound -> Output) :
I originally did this with my iMac but the screenshots in this post were created using my MacBook Air.
And that should work. The Bluetooth audio (at least with the settings I used) will have a slight delay in comparison to the system speakers. Bluetooth has a relatively short range so the practical applications of this method may be limited by obstructions within one’s home and the receiving capability of the Bluetooth device that is used.
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Thanks for this! After doing this however, I’m getting a humming that’s coming from the internal Mac speakers. Any idea on how to fix that?
Sam did U ever find out how to get rid of humming???
Help!!!!
I noticed that the humming or static does not come out of the Master Device that is chosen. the static will switch as I switch which device is the master. Sample rate did not seem to affect it at all. did you ever get an answer to this?
AMAZING!!!! Thx 🙂
That’s exactly what I need, but, please, where is the “Audio Midi” setup application, in Yosemite? Thank you in advance!
On my system it’s located at Macintosh HD -> Applications -> Utilities -> Audio MIDI Setup.app
Under Utilities
I have a half second delay between the speaker and my mac, any idea about how to solve it?
cheers.
I checked the drift correction box for the bluetooth device and don’t notice the delay.
Me too.. Got a B&O A2 and A9 speaker but they do not play synchronized..like you a half second delay!
I have a bluetooth speaker playing iTunes in my shop from my iMac, problem is I’d like to have all other functions on my computer use the internal speaker, such as youtube etc, Is that possible?
Great, just what I wanted. Only problem is it seems like I can’t control the volume with the usual controls. Is there anyway to do this?
I’m not certain though I ended up not using this feature for very long. These days I have the iMac set to send all sound output only to a Bluetooth speaker.
I’ve also used this method in an attempt to send audio to two Bluetooth speakers at the same time. It was able to connect to both but in practice it didn’t work – the audio dropped on both speakers constantly – I don’t know if it was a limitation of the Bluetooth radio, the OS, or both. It seemed like it simply wasn’t capable of reliably sending an audio stream to two Bluetooth devices at the same time. I wasn’t very surprised as it’s probably not a common thing that someone would have a desire to do.
Did you ever find out how to control the volume?
Game changer! I’ve been looking for this fix for so long. Will give it a whirl
I also get humming/crackling on internal speakers when external bluetooth speaker also selected. Pretty poor.
Fantastic. It really feels amazing when something in this world is easy and just works.
I have just installed a pair of bluetooth speakers on my iMac (Yosemite) because the audio out/headphones port died, after a good many years driving my original Apple external stereo speakers (a collectors item, that still work!). I found immediately that the sound quality from the bluetooth speakers was not good; choppy and crackling. After much experimenting I realised I had 3 other devices running in the bluetooth menu – keyboard, mouse and trackpad. Turning ONE off (trackpad in this instance) resulted in mush improved sound! They are good speakers (Sandstrom) 15w x 2 and I also use Boon2 to enhance the sound – now very happy.
I maked it work and its crazy! but after changing to another song there is a half second delay! How can i fix that?
Hi!
Many thanks for this advice. But … unfortunately, I cannot change the volume by this new virtual device.
get lots of lag I’m afraid, any idea how to sort this?
Awesome!! Was able to do this within a minute.
Thank so much!!
My external speakers are considered “built in output” when plugged in, so I cannot select the external speakers and the built in iMac speakers for the multi-output device. Is there a way to use both of these output devices as a multi-output device?
Didn’t work for me. I have the aggregate set up but my Mac will still only output to one device. I have aa JBL Pulse 2 bluetooth speaker and speakers plugged into the headphone jack.
Thank you, it was very easy and was almost exactly what I want…
I put the output to two different bluetooth speakers (Headphone and Harman/Kardon speaker), now I’m seeking for a possibility to send the left chanel to both chanels of one device and right chanel to both chanels of another device?
sorry for late reply. i’m thinking now about the same — want to purchase two bluetooth mono speakers and connect them together. Did your solution with two simultaneous work now? Have you tried to use aggregate device instead of multi-output to redefine channels?
Hi, late reply is mine now lol
If I remember well I couldn’t do that. Now I’m using Windows again, I’ve changed my job, so now the new company gaves me a HP Notebook. As I don’t need PC or Note for personal use, I’m not a macos user anymore.
If you have lag or crakling, try to check the drift correction in audio midi…
Try to change the master sound in your new profile audio agregate (multi output device) too….
It helped. My turned out that build-in as master, drift correction checked for both to be the best.
Increase sample rate might help too.
Thanks, This works well on OSX 10.11.3 with a Jambox in another room–even with a bluetooth keyboard and mouse.
Only annoyance is volume adjustment, which doesn’t work when on Multi-Output Device. I have to switch the output to just one device (Internal Speakers or Jambox), adjust the volume like normal, and then switch it back to Multi-Output Device. Works well enough, but interrupts audio in the other room.
Didn’t work. After making an aggregate device and selecting built-in and bluetooth i get “The selected device has no output controls” when I go to system preferences sound output. I press play on itunes and the sound output automatically changes from aggregate device to only bluetooth.
great this .. only this is that when I followed the steps above I can not alter volume via imac or my bluetooth speakers?
If you go to the AUDIO MIDI Setup-> Sow Audio Devices. Click on Built-in output and/or your bluetooth output. It will show two bars, numbered 1 and 2, for changing volume 1.
You Genius! Thnks
Didn’t work. Using 2 OontZ Angle speakers on a Macbook Air. Bluetooth icon shows both OontZ’s as connected. Icon does not show Multi-Output Device – should it?
Getting sound only through one speaker and very choppy at that. Preferences/Sound shows both speakers and Multi-Output Device. Speaker types are Bluetooth – Multi-Output Device type is Aggregate device.
Only other Bluetooth device is mouse which I disconnected to no avail.
Any thoughts?
Bruc
Thanks !
Fantastic, Just works in Sierra. This Xmas buyer 3 bt speaker and they works simultaneously. Amazing!
Thank you! I am now able to transmit music to both my treatment rooms from the same computer 🙂 I feel so hi-tech~
Volume control: I couldn’t control volume through the normal keys, either. I was able to control music volume through iTunes, though. Thanks for the great tip! Feel like I can rock out again 🙂
Still getting horrible buzzing in my bluetooth JBL speaker. Any help?
WORKS GREAT THANKS
Perfect! Now my Holiday Party is really gonna rock!
Hey, thanks for this, was just looking for info on pairing my bluetooth speaker, but came across this and now I have an unexpectedly pleasant 3-speaker surround setup going 🙂
Wanted to offer a tip for those lamenting the loss of their volume button functionality. Which is indeed mighty lamentable, verging on infuriating. I haven’t tested it much, but the tip is as follows: If you are in whatever app your music or sound is coming from, try holding Shift and hitting the up or down keys. So far I’ve tried it in Amazon Music, as well as watching Netflix in Safari. Worked brilliantly both times. I presume it would behave similarly elsewhere. Obviously not as good a hitting a single button that will globally change volume regardless of the app you’re in, but at least it spares you the need to go mousing around for a tiny volume slider.
THANK YOU!!!!
Awesome, great post – thank you! Only shame is the bluetooth lag problem, can be minimised a little by playing with computer speaker settings 🙂
I apologize… Still new to my new iMac which much to my beloved with the PC is being slowly lured to my beautiful new toy. I can not find this option on my iMac. I’ve open Midi Setting and it does not give me the multi-device option. What am I missing? Getting ready to buy additional speakers. Do I need to add the speakers before I have that ability? Would Bluetooth or wired speakers be recommended?
Awesome information you provided there, however my bluetooth speaker has a delay of 0.5 seconds, so it’s really terrible to listen to it.
Is there a way to also fix this delay?
I read some people fixed it but they’d didn’t share how.
Please help.
thanks
Hi guys,
I use this method to play the drums by having headphones plugged into my Mac so I can hear songs and at the same time I’ve put it on my bluetooth sound bar so everyone can enjoy what I’m playing.
I had a delay until I found a this :
Check the drift correction on the bluetooth speaker your are using and not the main source. I think it was set up on my mac by default but once you correct this, everything gets perfectly timed.
Hope this helps.
Have a nice day and be safe
how and where can I find the drift correction on the bluetooth speaker?
Then how can I correct this?
Currently I’m using the 3,5 jack to do this as I can’t get rid of the delay over bluetooth.