Yamaha B100-115III - Bass Amplifiers - Fair

Why This One

• Fair condition — a fully working unit at a great price
• Made-in-Japan 1980s Yamaha with dual parametric EQs and bi-amp capability.
• A rare find for bassists seeking a boutique-quality vintage Japanese combo amp.

Condition: Fair

This Yamaha B100-115III is a fair-condition bass amplifier. Our 10-point functional test was completed in full: all checks passed except volume controls. Please review all photos carefully, as they provide an accurate representation of the cosmetic condition of the product.

What's Included

• Yamaha B100-115III
• No additional accessories included

About This Model

The Yamaha B100-115III is a 100W RMS bass amplifier built around a single 15" speaker in a ported ¾" birch plywood cabinet, and was made in Japan during the 1980s. Its preamp section offers active Treble, Middle, and Bass tone controls alongside two fully parametric EQs — each with ±15dB of level adjustment, variable Q from 0.35 to 3.0, and a frequency range spanning 50Hz to 2.5kHz — making it unusually flexible for its era. An adjustable crossover (100Hz–5kHz) with discrete HPF and LPF outputs enables bi-amping configurations, while a balanced line out, Pre Amp Out, and headphone jack round out a comprehensive output section. The B100-115III has earned a cult following among bassists for its clean, transparent tone and old-school low-end character, with a reputation for punching well above its wattage in real-world headroom.

A great opportunity to own a Yamaha B100-115III at this price point.