If you want to use all of those connectors you're going to need more than just an optosplitter at the
console. You're going to need a repeater at each and every
plug.
DMX is meant to be a linear multidrop
network, meaning that it should be cabled from one device to the next to the next with no splits or branches and no stubs any longer than absolutely necessary. From what you've described, all of those male
DMX connectors being daisy chained comprises a linear multipoint
topology. But if you start adding cable and receiving devices to those connectors, you're going to turn it into a branched
network, which means an
impedance mismatch (source of signal reflections) at every split and excessive loading on the
driver (
console) even if you don't have more than the standard 32 devices on the
network.
You can get around this by placing a repeater on each of those connectors because the repeater is just another receiving device as far as the backbone of the
network is concerned, but will repeat all data from that backbone onto its output which is, electrically, the head end of an entirely separate
DMX network. The repeaters need not be optoisolating for this purpose, since you're unlike to get
ground potential differences of any significance, but you can opt for optos if you want the protection they provide.
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The other option is to split the
DMX line at each of the existing male connectors so you have a female on the side towards the board and a male on the other side. When you need to use one of those points, hook whatever devices in between the two connectors; otherwise just keep the male and female mated so that you can use downstream ports. However with this method, you're limited to 32 devices total sicne it's all one single
network. Whereas with a repeater on each
connector you can have up to 32 devices
per each output.