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



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

Key features:

  • DC heaters for the drivers and the power tubes
  • Lundahl Output Transforms
  • Mundorf Supreme Silver/Oil or Jensen Copper/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 6SH7
  • Please note: The 300b tubes are NOT included with the amplifier. It's up to you to provide the 300B's of your choice. For testing the amplifier I use Genalex Gold Lion PX 300B's. Some day I hope to 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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