Re-Tube & Amp Biasing

General Tube Amp Maintenance

General Tube Amp Maintenance includes the following:

Adustable Bias Amps; $75 (tubes/parts not included)


Portland Pro Audio 611 N. Tillamook St., Portland OR 97227 503-406-1881

Properly adjusted bias of the output tubes will maximize tube life while providing a strong and healthy tone.

The correct bias point for new tubes drifts quite a bit over the first few days of operation but after that, the characteristics stabilize, to a large degree. Because of this, we only order burned-in, match tubes sets from our suppliers or recommend our clients to purchase from Eurotubes.

Unfortunately tubes drift over time your tubes will require a different bias voltage in order to run at optimum performance. Failure to keep tubes properly biased can significantly reduce an otherwise fine tube's lifespan

Burn in and Set Bias in Amplifier; $55 (tubes not included)