Over 5,850 new and vintage individual models are identified in detail with current new or used market retail values, and many are included. 18,000+ values are included and many have been updated to reflect the current state of the vintage guitar amp marketplace, taking into consideration that large heavy amplifiers are not as popular as they used to be, and values are down. Nearly 2,000 B&W images are included in this newest edition with 3,650 available online in high res color. The "t" in the text indicates that one or more images are available for viewing directly on our website in full color for free! The revised 16-page color Photo Grading System (PGS) is included to help properly determine the condition of any amplifier – the most important factor when assessing accurate value. Also included is a thorough Anatomy depicting all the individual components of an amplifier, plus an extensive Glossary that explains amplifier terminology and definitions. The Trademark Index is incorporated directly into the text with contact information for nearly all current trademarks/builders, and once again, all the current/recent boutique amp builders are listed, and many have individual model listings. Turn it up – if it's too loud, you're too old!