Hairball Audio Elements Mic Preamp Series

Projects > Hairball Audio Elements Mic Preamp Series

The Hairball Audio Elements series of DIY mic preamps provides several new takes on a classic preamp topology: transformer-coupled I/O, and a single discrete op-amp for gain. Designed in conjunction with respected DIY audio product maker Eisen Audio, the preamps are 500-series compatible and come in several variations based on op-amp and transformers used.


  • 4 preamp variations:
    • Gold:
      • “Clean” preamp; uses Jensen 990-derived opamp and Jensen transformers
    • Copper:
      • “British”-style; original-design Eisen Audio opamp and Ed Anderson-designed and built Carnhill reproduction transformers
    • Bronze:
      • LA-3A-inspired; original-design opamp and Cinemag/Ed Anderson LA-3A reproduction transformers
    • Silver:
      • DIY platform; multi-configuration preamp with 2520 and DIP-8 opamp footprint compatibility and multiple transformer footprint compatibility
  • Each preamp:
    • 63-65dB of gain
    • 20dB pad
    • polarity invert
    • DI input
    • Choice between variable and stepped gain
    • Output trim


  • $315 for Gold, $295 for Copper and Bronze, $95 for Silver (all are full component kits)

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