R8600 Speaker Jack...Mono or Stereo?

[MTScannerNut]

Does anyone know if the external speaker jack on the back of the R8600 is mono or stereo? Reason I ask is because I want to try a speaker with 3.5mm aux jack which calls for a stereo 3.5mm cable. If it is mono, can I safely plug a stereo plug into it without risking damage to the receiver? Thanks, Ed

 

[MTScannerNut]

For anyone interested, I decided to try the 3.5mm stereo plug cable I had and it works fine on the R8600. Outputs sound to my Bose speaker nicely. So if it is a mono jack, it appears to accept a stereo plug just fine.

 

[Randyk4661]

For others that read this post, If you insert a mono plug slowly you will get a small amount of resistance as the tip passes one or two contacts. If it only clicks after fully plugged in, It's mono. If it clicks before fully inserted then goes all the way in, it's stereo. Also using a mono plug in a stereo jack won't hurt the radio, You only get one channel (Left side) on a stereo player like a car radio. If it's a relativity new unit, it's going to be a stereo jack.

 

[kruser]

Also using a mono plug in a stereo jack won't hurt the radio, You only get one channel (Left side) on a stereo player like a car radio. If it's a relativity new unit, it's going to be a stereo jack.

Not quite true.
If you plug a mono plug into a external stereo speaker jack that has been wired to supply mono audio (such as a scanner) to both the right and left channels of a stereo jack for feeding another audio device or external speakers, you will short the ring to sleeve through the mono plugs sleeve which will then short the entire audio output completely. Depending on the radios amp circuit, a dead short could cause damage to the audio amp. This is true for a direct speaker output such as an external speaker jack.
They sell stereo plug to mono jack adapters for this problem. The adapters grab audio from the tip and sleeve and leave the ring terminal open to eliminate the short.

If the jack is rated for headphone output, then a mono plug may still produce a short depending on how they wired the jack but it would have much less chance of hurting the audio amp as they are usually limited in output level these days to reduce hearing loss lawsuits. The audio limiting makes it impossible to completely short the output on modern equipment with headphone outputs.

Looking at the R8600 schematic, it shows the rear external speaker jack is indeed a stereo jack but they did left the jacks ring terminal floating so either type of plug may be used without issue.