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Vintage Dynaco Vacuum Tube Amplifier Technical Articles & Information
Dynaco
Vintage Tube Amplifier Technical Articles & Resources
Dynaco ST-70
ST-70 Power Amplifier
Analysis and measurement of the the ST-70.

Dynaco PAS 2 , 3,  3X
PAS Preamplifier
Analysis and measurement of the
PAS phono stage.
Analysis and measurement of the
PAS line stage.
Analysis of the PA-211 power transformer.
What to be aware of when driving
lower impedance SS power amplifiers.
How to bypass the tone controls for reduced output impedance and improved linearity.
How to tell if it's a PAS 3 or a 3X with the special tone controls.

Dynaco SCA-35 & ST-35
Enhanced fixed bias (EFB™) modification to increase power and lower distortion.
Analysis and measurement of the SCA-35 Phono stage.

General Information
Understanding the recording process and RIAA equalization.

Parts Suppliers
Upgrade & restoration PC boards for Dynaco SCA-35 and ST-35.
Dynaco tube amplifier reproduction kits, parts and accessories.
Dynaco tube amplifier restoration parts and accessories.

If you have questions regarding any of he posted articles, or products previously produced by Audio Regenesis.
Pacific Audio Regenesis
After an absence of several years, Pacific Audio Regenesis has re-emerged on the vacuum tube audio scene. The intent is not to revive the old AR product line, rather, to provide information related to the preservation and restoration of vintage Dynaco vacuum tube amplifiers. Information and articles will be posted as they become available.

Upgrade and Restoration Boards from D. Gillespie Designs
Some of the most popular, and beneficial, Dynaco upgrade and restoration boards from the discontinued Audio Regenesis product line are still available, as bare PC boards only, from D. Gillespie Designs. Visit Dave's Store for more information.
Boards for the Dynaco SCA-35 Integrated Amplifier:
SCA-35*EFB™ Power Supply Board
SCA-35 EFB Power Supply
Perhaps the most significant upgrade available for the SCA-35
If you do only one upgrade to your SCA-35, this should be it! Converts the SCA-35 from cathode bias to Enhanced Fixed Bias for increased output power, lower distortion and extended tube life. Also replaces all the capacitors, resistors and rectifier diodes associated with the power supply. Purchase from Dave's Store

*EFB™ is a trademark of D. Gillespie Designs
PC-10A Output Board Set
SCA-35 PC-10A Driver Board
The PC-10A replaces the obsolete, increasingly hard to find, and expensive 7199 driver tube with either a 6GH8A or 6U8A. Note that this is not just a tube swap. Additional components have been added to prevent stability issues that can occur when these tubes are simply used with adapter sockets in the original PC-10 board.
Purchase from
Dave's Store
PC-11 Preamp Board
Dynaco SCA-35 PC-11 Phono Board
Perfect for restoring your SCA-35 with modern components while maintaining the stock circuit configuration.
The original Dynaco component mounting hole spacing and eyelet placement is retained for easy drop-in replacement.Purchase from Dave's Store
Boards for the Dynaco ST-35 Power Amplifier:
ST-35 *EFB™ Power Supply Board
Dynaco ST-35 EFB Power Supply
Convert your ST-35 from cathode bias to Enhanced Fixed Bias for increased output power, lower distortion and extended tube life. Replaces all the capacitors, resistors and rectifier diodes associated with the power supply.
Purchase from
Dave's Store

*EFB™ is a trademark of D. Gillespie Designs
PC-13 Output Board Set
Dynaco ST-35 PC-13 Driver Board
Perfect for restoring your ST-35 with modern components while maintaining the stock circuit configuration.
The original Dynaco component mounting hole spacing and eyelet placement is retained for easy drop-in replacement. Purchase from Dave's Store
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