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Here is the predicament I would like to connect a set of AKG K1000 passive headphones to the Beocenter2500. The K1000 requires more power output than the headphones-out on the 2500 can deliver so the solution would be to attach an ML-MCL unit via one of the PowerLinks outputs. However as I understand it this would not allow for volume control to be independent of the other PowerLinks output on the 2500 (or am I wrong?). The other PowerLinks has a set of Beolab8000 and I need those to shut down when the K1000 headphones are playing.
Would it require two ML-MCL units to pull this off, one for the Beolab8000 and one for the K1000 to have independent volume control?
Appreciate any input here.
Regards
/K
Welcome to Beoworld!
The two PL outputs on the BC2500 are effectively wired in parallel, and are hence both volume controlled (in parallel) from the front panel or remote.
Have you considered keeping PL for just your BL8000s, and then using the AUX socket (which is an fixed line-level output, as well as an input) to provide a separate output, which could then be connected to a bespoke headphone amplifier with its own volume control?
There are solutions that I can think of with the 'double ML-MCL' option but they get unnecessarily complex!
Thank you for the Welcome.
Appreciate your thoughts. True, the AUX-line could be used however I had other plans with that port -AUX-IN to take a line-input from a Samsung TV or from a Bluetooth converter to give smart phones/tablets access - and used the AUX-OUT to feed a line signal to an infrared headphones converter to blanket all kids in the living room with IR from the TV and keep it nice and quite for the rest of us.
As you said using the AUX would require the headphone amplifier to have its own volume/remote control however, I wanted to keep it B&O integrated, i.e. volume control through the Beocenter and its remote.
I'm not familiar with the programmability of the ML-MCL, so correct me if I'm wrong here: If I connect the BC2500 via the PL to the first ML-MCL and then string the second ML-MCL via the ML would I then be able to program (link) the units to have individual volume control via the remote (BEOLINK5000) for the BC2500?
The BEOLAB 8000s could get a PL feed (and split) either directly from the the remaining PL port on the BC2500 or from a PL port on either of the ML-MCL units not servicing the passive headphones.
Would this require an IR-eye unit to work?
Hmmm - it seems that you are trying to achieve quite a lot with an old bit of kit (the BC2500) with very limited inputs/outputs!
Two simple solutions:
- Buy new headphones that can be powered by the BC2500!
- Use the second PL output to power the headphones via the ML/MCL, but manually switch off the mains power to the BL8000s when using the headphones.
And one slightly more complex:
- Build an adaptor box so that a single PL output can be manually switched between either the BL8000 and a ML/MCL that will power the headphones.
Bear in mind that you should also tailor the ML/MCL amplifier output to the input requirements of the headphones, hence may also need to employ a circuit like this: http://sound.westhost.com/project100.htm
Other solutions will need to use the line-level aux output of the BC2500, connecting one PL and AUX to a Beolink Converter 1611, then running ML cable to the ML/MCL (acting as a 'Passive' for the headphones) - the ML/MCL would then need an IR eye and would be treated like a separate LINK zone in a multi-room system. You'd have to get the correct option setting - A.OPTION 6 possibly - which would enable you to use your BL5000 to select the headphones by pressing LINK then the source (having already muted the BC2500). Complex, but should work!
(EDIT: You would only need AUX to be connected between BC2500 and the ML/MCL, as in this case the variable volume for the headphones would be provided by the IR eye, and not the BC2500 - which can be muted independently)
Can't the kid's headphone IR transmitter be connected straight to the TV?
Guy: Other solutions will need to use the line-level aux output of the BC2500, connecting one PL and AUX to a Beolink Converter 1611, then running ML cable to the ML/MCL (acting as a 'Passive' for the headphones) - the ML/MCL would then need an IR eye and would be treated like a separate LINK zone in a multi-room system. You'd have to get the correct option setting - A.OPTION 6 possibly - which would enable you to use your BL5000 to select the headphones by pressing LINK then the source (having already muted the BC2500). Complex, but should work! (EDIT: You would only need AUX to be connected between BC2500 and the ML/MCL, as in this case the variable volume for the headphones would be provided by the IR eye, and not the BC2500 - which can be muted independently)
that`s what I thought as a solution, but it`s a bit "overkill" isn`t it? And you will need the AUX socket.
But if you are a proud owner of a solder iron, a little Powerlink-switch-box (what a word!!) could be a nice, cheap and very special solution.
The PLS box (you know what is meant...) should have one PL input 7(or 8) pin DIN and two PL (DIN) outputs. All wires should be led directly from input to both outputs (as it is in your BC), only PIN4 should be switched by a simple AB switch on top of the box.
PIN 4 is for Speaker on/off signal(about 5V). Switched to position A it will activate all Beolabs connected to the PL output. Switched to B it will activate the Headphone amp - a little MCL2P should do it - connected to the second PL output. Only one PL output will be active.
Place the PLS box near your preferred listening place and install one PL cable from your BC2500 to the box, a second PL cable to Beolabs via PL splitters and a third PL cable from box to headphone amp. You can use the AUX socket for other purposes. Although there might be a problem to connect two different devices to the same AUX socket - in- and output use the same ground. This might (!) cause noise, hum, whatever...
Just an idea, that I`ve never tested...
Stefan
Thanks for chipping-in with some expert knowledge Stefan - there is indeed a danger of being over-complicated here but at least I have found a good use for the white board in my office! Must do some work now ...