Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: Can I connect multiple headphones with a single source
Document: I purchased these headphones back in March, my intended use is for watching TV without disturbing my wife.For that use, they sound good, fit good and I like them but I have had several issues with them.First I have had trouble providing them with the proper source level. If I connect them directly to the audio out plugs on my cable box (comcast Motorolla box) the source level is almost too high.
The IR headphones were very sensitive to how I moved my head, to incidental objects on my desk (that might block the transmission path) and would cut out if I took a single step outside of my home office.
clear sound - good range (distance from the source) - comfortable to wear. The ear pads go around the ear so it is more secure than the headphones that have the flat ear pads that rest against the ear. The base frequency is lacking in this model so I had to drop a star.
I was a little hesitant to order these headphones, but was very pleasantly surprised. The sound is very clear (unless you have the tv too loud). I even forgot about them & went to my basement with them on and had very good reception there also. The only problem I had with installation was that I had to connect them to my cable box instead of directly to the TV. Once I figured that out, everything worked fine.
These headphones are really nice. Great sound quality and have a good reception distance. The only thing I didn't like is that the only input is via RCA phono jacks, which of course, I didn't have any audio output like that on my new LG flat screen. So, I had to buy an adapter and connect to the cable box with a digital audio coax cable.
I gave these headphones to my husband for Christmas. I got them at a great price, and we were able to set them up today. I have a few hints for those who might need them.We have an older Yamaha sound bar, and after a call to Amazon for tech assistance (free for 30 days from product arrival), we found we weren't able to connect them this way. However, we were able to connect them to the TV.
These work just fine for me. The sound is clear and detailed, even when I wander to the other end of an 1100 sq ft. apartment. No hiss or distortion, except that they eventually squeal if the sound source goes completely silent (easily solved -- turn the TV on before turning on the headphones, and take them off before turning off the TV). Reasonably comfortable for the duration of a movie, though they get a little warm. Easy to set up.
Would buy it again - good value and came with all the necessary hardware to connect. A bit hard to get the spring loaded plug in the recharging station to line up when replacing the headphones, but that is a very minor annoyance.
I could not use even a single time without fail, At all times have signal interference and do not hear anything.
Works great even at 50 to 70 feet from A/V source through walls and doors. We have a bedroom TV hooked to a COX cable box that when turned off will not activate the base to charge the headphones. Our primary TV is running through a COX cable box but is also controlled by a SONOS bridge and a DENON receiver that keeps an ongoing A/V signal that enables the base unit on this system to charge the headphones 24/7.
Answer: I am not sure. I also wanted to try this, but I was not able to find any extra headsets for this base other than the combo found here on amazon