I just picked up an Acme Low B-1 series 3 at a local music store. It has the three speakers (like all Acme cabs) but no attenuators for the 5" speaker or horn. Did they get rid of the attenuators on the series 3? There isn't much info on the Acme site. The cab sounds great, so I don't think anyone modified this or did something dumb - like removing the control plate on the back. I'm just surprised that there's no control over the various speakers.