Welcome to GerusAudio, Manufacturer of Semi-Custom Stereo Tube Amplifiers



The vision of GerusAudio is to build affordable, aesthetically appealing high quality tube amplifiers. 

The amplifier pictured to the left is the prototype for the GerusAudio A3 and 300B series. 

Key features:

  • DC heaters for the drivers and the power tubes
  • Lundahl Output Transforms
  • Mundorf Supreme Silver/Oil Coupling Capacitors
  • Illuminated On/Off Switch
  • Audio grade Toroidal Power Transforms
  • Unique hardwood and steel chassis

What is a Semi-Custom Tube Amplifier?

At GerusAudio we build the chassis in advance, you select from what is completed or in process.

What does that mean to you?

  • You purchase a product with the appearance and power level that suits your tastes/needs
  • Lead time is reduced
  • Upgrade options available

Available power tube options:

A3 Series:

  • 6A3 or 6B4G

300B Series:

  • 300B with C3G or 6SG7GT
    *Please note, all GerusAudio amplifiers can be purchased without tubes (for example if you are lucky enough to own a pair of Western Electric 300B's!)

Design Philosophy


GerusAudio uses high quality parts.

  • Lundahl OPT's 
  • Mundorf Supreme Silver/Oil 
  • Vintage tubes (when available)


At GerusAudio we believe the amplifier needs to look as good as it sounds. 

Price Point

GerusAudio offers a competitive price point for an American made product. 

Power Tubes

Why use a 6A3 or 6B4G instead of the 2A3? 

  • The 6A3 and 6B4G are the same as a 2A3 from a power output standpoint.
  • They sell for about 1/2 the price of a NOS 2A3
  • They work perfectly with DC heaters
  • Readily available


Why use Pentodes for the Input/Driver?

  • To get the required voltage gain with just one tube / one stage
  • Only one coupling capacitor required
  • High current compared to triodes

Contact Information



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