This happened months ago, and I am finally getting around to posting it - So I was at a local music shop that I've visited in the past. I've never had any complaints with the place - they usually have great prices and really nice equipment. I was talking to one of their employees (coincidentally a bass player who gave lessons at the place) about bass amps and cabs. We got on the topic of impedance and discussed connecting an 8ohm cab with a 4 ohm cab to a head that goes down only to 4 ohms. It went something like this - Me - "So this head has a nominal impedance of 4 ohms, will I be able to connect this 8ohm cab and this 4ohm cab to it at the same time?" Employee - "Well if you connect an 8ohm cab with a 4ohm cab you'll be at around 6ohms so you will be fine" It was after going on talkbass that I learned he was horribly wrong. But what if it was somebody else and they ended up spending thousands of their hard earned dollars on this rig which the employee said would function without any problems, then they use it at a gig and it craps out on them?? Share your thoughts/experiences.