Effect Information

“Yamaha G100-112 (100 watt solid state amp with a HD 12″ speaker), year of manufacture probably in the 1980s. This is another love of my life. This amp is great and damn loud, in fact it’s known for getting way loud and staying way clean (on the clean channel). There is also a distortion channel controlled via foot switch. It’s got a volume knob with a FAT setting, a gain knob with a FAT setting, # band EQ with BRIGHT setting, and a sweet parametric EQ. It also has built in verb settings.”

Very interesting amp

  • The parametric EQ is definitely one of the unique features of this amp
  • What a workhorse
  • Crafted in the late 70s – early 80s
  • It has two channels — one clean — one overdrive — with a foot switch which also has reverb control
  • It has an output for an auxiliary speaker, a direct out and even a grounded outlet in the back
  • Not noisy and very clean

More information from another online listing


  • 10 silver and black knobs (pull FAT VOLUME, pull FAT GAIN, MASTER VOL., pull BRIGHT TREBLE, MIDDLE, BASS, PARAMETRIC EQ (Level, Q, frequency 500), and REVERB. All knobs are all functioning properly and no damage.
  • 120volts, 180watts and 60hz
  • 1 or 2:4 ~ 8 OHMS/SPEAKER
  • 1 + 2:8 ~ 16 OHMS/SPEAKER
  • CLASS2 WIRING MAYBE USED [whatever that means?]


  • Speaker size is 12 inches diameter YAMAHA
  • JA3063 is the model number
  • RMS Power Rating — 100 W
  • Impedance 8 ohms
  • Peak power rating — 300 W
  • Made in Nippon Japan

Some good discussion on this amp found here also. These originally sold with a foot switch and vinyl cover. That high sale price of $301.51 was on July 6, 2011. The low price was from 2008. A nice sounding and responsive amp.

Video Demo

Sales Data

Date Range (06/15/2022 - 06/15/2022)

Archived past online sales data:

Search Marketplace

More from this Brand