Ampeg had two different (and often confused) 18" cab models
SVT-18 has a 4 ohm speaker 500watts RMS, cab Dimensions (W x H x D inches): 24 x 25 x 22.5, 1/4" & speakon connectors
. Ampeg website specs http://www.ampeg.com/products/classic/svt18/index.html
This retailed at 1000$ dollars and was worth it.
SVT18e has an 8 ohm speaker 175 watts RMS, and is nowhere as deep as the other one (probably only 16" deep). only 1/4" connectors.
which one are you talking about?