Home theater bypass

Ok guys, here is a HT bypass question for whoever can answer. I asked it months ago on the Asylum when I was thinking of getting a Oppo 205, but nobody could answer.
I have a Mac C48 preamp that only goes into bypass mode by a 12v trigger from a processor. I have been working around this as my Oppo 105 that I use as a processor has no 12v trigger. 
So now I am about to set up my new 205 which has a trigger to put the C48 in bypass,  but what if I just want to play a CD and not HT,  how do i control that, if every time I turn on the 205, the C48 goes into bypass.

I searched the Oppo manual and it was no help.

A couple of ideas here.  If you are using a separate amp for center/surrounds, then you could use the 12V trigger output from that amp to trigger the C48 into bypass mode. 

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Another idea would be to get one of those 12V wall wart DC power adapters, chop the end and solder it into a 1/8" male mono plug.  Use that as the 12V trigger for C48 and then just plug it in when you want to trigger the C48 into bypass mode.

I have a Mac C48 preamp that only goes into bypass mode by a 12v trigger from a processor. I have been working around this as my Oppo 105 that I use as a processor has no 12v trigger.

Another idea would be to get one of those 12V wall wart DC power adapters, chop the end and solder it into a 1/8" male mono plug. Use that as the 12V trigger for C48 and then just plug it in when you want to trigger the C48 into bypass mode.

Same idea with some refinement :
Use a 12V wall wart DC power adapters with inline on/off switch and a 3.5mm Male to 5.5x2.1mm Female DC Adapter.
https://www.amazon.com/Gxilee-100-240V-Converter-Household-Electronics/dp/B01FXF6AEQ
https://www.ebay.com/itm/3-5mm-Male-to-5-5x2-1mm-Female-DC-Adapter-Converter-Jack-Power-Plug-CCTV-DV...
Turn on the inline switch if you want bypass.

So now I am about to set up my new 205 which has a trigger to put the C48 in bypass, but what if I just want to play a CD and not HT, how do i control that, if every time I turn on the 205, the C48 goes into bypass.

https://www.amazon.com/RDL-ST-ACR2-Line-Level-Audio-Controlled/dp/B01D96JVFG
Connect the RDL input to center channel or LFE output of 205, connect the RDL relay switch between 205 trigger output and C48 trigger input.
The HT bypass will be done automatically.

Thanks guys, good ideas, I will check them out.