A friend of mine is looking to buy a cheap combo and found the following options second hand however I can't find info on two of them. The details of the ads are.... Ampeg SVT 15T 300w Bass Combo. 15" speaker. exc cond. 400 Carlsboro Bass Amp. B150 series, 11band EQ, built in compressor, effects loop and DI in/out 150 watt, recently seviced, 125. Tracey Elliot Bass Amplifiier 120 watt, commando series, ex cond, 100 ono, quick sale I cant find info on the ampeg or the carlsboro. I'm not even sure if the ampeg model exists. He want's to spend as little as possible. Does anyone know if any of these models can be used with an extension cabinet? I reckon that the commando would be the best, cheaper option. Although the 300W ampeg would probably be best over all. What do people think. I suppose what I really want to know is if they can be used with an extension cab or not.