FYI there are 3 different iterations of the DSP420 speakers. IMHO they are designed like the 7K pairs to have a digital audio input/slave comms from the controller/G68 and then have the digital output/comms output go from one speaker to the other (perhaps in the ceiling). Since they are powered there needs to be power for the speakers in the ceiling, too. I checked the pic of the G68D, there are actually 3 comms ports, one is the newer style and you can craft an adapter.

You can daisy chain the L/R pair and also the center channel together. Don't stress out the first time you do it!

The age of the DSP420's might mean the tweeters are old and need to be replaced. Mr. Koval does that service, too.

Beware the 420's are heavy and need to be mounted appropriately. You could say the same about most of the DSP range. Lots of electronics/amps integrated inside the box.

Primary: 818v3+ID41, M6 stereo pair, M SpeakerLink cabling, Sonos+96kHz Cullen, silver DSW
HT: Marantz prepro, 271, DSP3300, 8K SE FL/FR pair, DSP M6x2, DSP320x4 (ceiling), black DSW, 520 RL/RR rear in-walls
Living Room: G65, 640 L/R in-walls, UHD722, MS600
Vac. Home: G61, HD621, 4xDSP3100, DSP3100HC
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