The icons for those two DIN connectors on the right are a tape recorder and a phonograph.  The tape connector is both input and output, so getting the correct plug wires is the key.  If you are using the vintage Beomaster 1200 because you are tight on cash, then the wiring is completely straightforward and there are wiring diagrams on beoworld.org.  If you are using the Beomaster because it is cool, I suggest *buying* a cable from soundsheavenly.com, which saves you the experimenting and soldering.  (Just tell Steve what you are doing; he has probably already done it himself but in any case he will guarantee that it works.  I used inexpensive DIN->RCA cables from amazon.com or ebay.com, but some were wired up for the output side rather than the input of the B&O tape in/out DIN!  The sellers usually don’t know.)

Side note, unverified: If the tape input doesn’t work, you can use the phono input for a line-level source like the Port.  Just set the “ohm” switch on the right to high rather than low.  I haven’t looked at the circuit but scuttlebut says either the RIAA curve gets disabled, or the input was originally designed for flat crystal cartridge in the first place.

Another side note: Not sure how experienced you are with that unit because your photo shows it not plugged in to your speakers, so… When ordering the connector cable, be sure to order a couple of 2-pin DIN connectors, i.e. those spade-and-pin jacks in the center, (preferably screw connector not solder-cup) for your speaker wires.  Shame to pay shipping for a lousy two ounces if you forget.  (Unless the friendly previous owner gave you speaker wires already terminated!)

P.S.  I believe the out/in wires mixup in the DIN plug is what happened to this other user:

https://en.community.sonos.com/advanced-setups-229000/sonos-port-bang-e-olufsen-beosound-3200-6838494

Your cable will look similar, but will only have 5 pins on the DIN plug end, because older B&O models like yours didn’t leave blank holes for all the pins -- that 7-pin plug physically won’t even plug into your 5-pin jack!

Dear “Tracker”, you’ve been of greatest help. In the meantime I have had repared both AMP and record player and then played around with named options  a lot. In the end, basicaly, what I have learned or rather what seems to be is that the AUX, or rather 7,5 mm headphone out works perfectly. It connects to SONOS AMP directly via aux to line in, with size converter jack for AUX from 3 to 7 mm. 

Also, I was quite surprised how well B&O tuner/pre amp/amp works connected in line with SONOS Connect Amp. The direct speaker din connection seemed to be full of static, now it’s smooth sailing. I didn’t have to try out Recorder in /out, bit I think it would work all the same. As for the sound, maybe it’s SONOS magical software, and I completely killed the old AMP sound, but it sounds devine, and Yes, to answer your question Mr. Tracker, I got into this endevour becouse I thought it looked cool, so as Jordan Peterson would say: so… :)

a pic for the end

Best 

Deva

Classic stero’s do look great!

Since you are using the Sonos Amp you can only use the “out” on the B&O. A Port would have given you the possibility to also use the “in” (via DIN) and opened up the world of streaming to your B&O.

@Bassamdeva thank you for the the follow-up response -- such is the true reason to help people on this forum, because I’ve no allegiance to Sonos anymore.  Your setup photo looks great!  Again thanks.

@106rallye you are correct in general, and I mentioned the Port above, BUT in this instance Deva chose the Amp because, “The direct speaker din connection seemed to be full of static,...” which means they are specifically avoiding the B&O amplifier in favor of  Sonos’s.  (Sure, it might just be corroded 2-pin DIN sockets, or maybe just spraying some contact cleaner into the volume pot, but it might turn out to be a whole nightmare of amp repair.  It still might, after a couple of weeks of use, if the electrolytic capacitors start to fail, but in that case -- again -- the Sonos amplifier will still play music, while they search for another beautiful tuner & phono preamp!)