Re: Alpine type r
You'll want a set of dual 4Ω subs in order to get a 1Ω load on the amplifier and doing that will get you the most power available out of almost any quality mono amplifier.
The only benefit to running at higher impedance is increased amplifier efficiency but, the trade off for a little bit of efficiency is a halving of output. And, there is no sound quality difference between 1 & 4Ω, so long as your amp is stable at 1Ω.
As for amps, the CT Sounds 1400.1 will get you a little over 2K and the 900.1 will get you ~1200. Personally, I wouldn't run 2kW to two Type Rs.
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