Skip to product information
1 of 14

Dynaco Dyna PAS Stereophonic Preamplifer Upgraded Tube Stereo Preamp

Dynaco Dyna PAS Stereophonic Preamplifer Upgraded Tube Stereo Preamp

Condition: Used

Regular price $399.00 USD
Regular price Sale price $399.00 USD
Sale Sold out
Shipping calculated at checkout.

For your kind consideration is this Dynaco PAS stereophonic preamplifer. It's in great condition with just a few very light scratches as shown in photos. It has been upgraded with a modern black faceplate showing input options for CD/DVD. The tube on far right is a vintage RCA 12X4 made in USA and the four 12AX7s are modern JJ replacements. Unit came from a working environment and is fully functional and sounds great. Enjoy!

The venerable Dynaco PAS is perhaps the most famous stereo preamplifier of all time, Much like the Dynaco ST-70, it introduced the magical sound of tubes to thousands of audiophiles throughout the past decades. The PAS is still a popular model, both in stock form or as a platform to be tweaked and modified.

All PAS preamplifiers share the same circuit: For the phono stage, one 12AX7 per channel, each section in series, using loop negative feedback connected to a capactior and resistor network to provide the RIAA equalization.  For the linestage, a 12AX7 per channel, each section in series, utilizing loop feedback to lower distortion and provide a low enough output impedance to drive cables into a high impedance input of an amplifier.  Power supply rectification is handled by a 12X4 tube.  Filaments for the 12AX7s come from a voltage-doubler circuit, which - as the namesake suggests - doubles the supplied AC voltage from the transformer and smooths it out to DC.  Having DC on the filaments also helps to reduce hum.

Specifications

  • Frequency response: 10Hz to 40kHz
  • Total harmonic distortion: 0.05%
  • Gain: 60dB (MM), 20dB (line)
  • Signal to noise ratio: 74dB (MM)
  • Valve complement: 4 x 12AX7 (ECC83), 1 x 12X4

*All orders may require a signature at time of delivery unless discussed prior to shipment.

*International customers will need to pay actual shipping cost if amount is greater than estimated shipping charge shown. In many cases, international shipping may be less than price shown. Please contact us with your country and postal code prior to purchase if you need a shipping quote, and we will send an offer with exact correct shipping charges.

Shipping:

*All orders may require a signature at time of delivery unless discussed prior to shipment.

*International customers will need to pay actual shipping cost if amount is greater than estimated shipping charge shown. In many cases, international shipping may be less than price shown. Please contact us with your country and postal code prior to purchase if you need a shipping quote, and we will send an offer with exact correct shipping charges.

View full details