You can - but you will need what are effectively "double adapters" for the RCA plugs.
Here's one example:
http://www.jaycar.com.au...oductView.asp?ID=PA3560
This would have to plug into first amp, and you would run your lead from your head unit into it, and one out of it to the second amp. It doesn't matter which way is in or out in the adapter - the signal travels both ways. You will need 2 (L+R)
Or here's a similar one that's all female:
http://www.jaycar.com.au...oductView.asp?ID=PA3562
Again, 2 are required (L+R).
You can run your head unit's RCA leads into this, then use another 2 pairs of leads - one out to each amp.
Probably a bit neater than option 1 if your amps are in view, as you can hide these behind trim.
There is one last option - well it's 2-fold:
1. Delete the rear speaker amp & simply run the rear speakers off the head unit. This is ideal if your rear speakers are only for "fill" - as they should be in a quality sounding system. Your fronts should be doing the majority of the work anyway (apart from the very low frequencies that the subs cover).
2. Run a line-level convertor off the rear speaker outputs, to reduce those speaker level (high level) outputs to the (low/line level) RCA levels suitable for an amp. This will be a "dirtier" solution than the RCA adapters though, which will impact on sound quality.
Cheers,
Mick
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