Here's the inside of the Dynavox: beautifully clean, stunningly simple, and......missing a power transformer. On the plus side, that makes the amp so light you could pick it up with one finger. On the downside, it also makes the amp a serious electrical shock hazard. Manufacturers commonly left out the power transformer to save money. We'll install an isolation transformer and a three-prong cord to make this the practice amp nature intended. One last thing: this is, in fact, a tube amp. The tubes, which plug in behind the chassis, are the original branded Dynavox tubes..