Tag Archives: pas

Dynaco / Dyna-Kit PAS 3X Tube Preamplifier

18 Feb

 Dynaco / Dyna-Kit PAS 3X Tube Preamplifier

Designed by Ed Laurent and introduced by Dynaco in 1966, the PAS series of stereo amplifiers are renowned by audio enthusiasts the world over.

As with many Dyanco products, the preamplifier was sold under the Dyna-Kit name for $69.95 as a build it yourself kit.  There was also an option to buy it fully assembled for $89.95.

Check the back panel of your PAS preamplifier - if the speaker binding posts and RCA jacks are attached with screws, then it was originally built as a kit.  If there are rivets, you have a factory wired unit.

During the PAS production years, Dynaco sold over 100,000 PAS-2, PAS-3 and PAS-3X preamplifiers.

The difference between the PAS-2 and PAS-3 preamplifier is the PAS-2 has a flat brass faceplate with plastic knobs, and the PAS-3 has a silver anodized faceplate with metal knobs, otherwise both preamps are the same.

The PAS-3X preamp has a revised tone control circuit which takes the tone controls out of circuit when set to the flat position.

More specs and pictures after the break.

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Dynaco PAS /2/3/3x Tube Preamplifier

16 Nov

Dynaco PAS PAS2 PAS3 tube preamp

Dynaco PAS Series Tube Preamplifier (PAS / PAS2 / PAS3 / PAS3x

The Dyanco PAS-3X stereo preamplifier is a two channel control center which permits either monophonic or stereophonic reproduction from any program source, with any modern amplifier.

This preamplifier design is most renowned for it's low noise and distortion, and it provides striking simplicity of operation while retaining full flexibility for the enthusiasts subtle adjustments.

Form Tube stereo preamplifier
Frequency response 10Hz-40kHz±0.5dB (Aux)
THD Below a measurement limit
Cross modulation distortion 0.05% or less (at the time of 2V Output power)
Signal to noise ratio Phono:74dB
Aux:85dB
Output voltage 10V/100kohm
Phono allowable input voltage 250mV
Tone control Bass: ±20dB (20Hz)
Treble: ±18dB (20kHz)
The semiconductor used 7:4 12AX
12X4:1
Dimensions Width 343x height 108x depth of 230mm
Weight 4kg
Option Wooden case (3,900yen, at the 1960 in-the-late time(?))
Wooden case DW-1 (6,500yen, around the 1976 time(?))

Specifications

Inputs: 3 stereo low level, RIAA phono, NAB tape head, special, 4 stereo high level

Distortion: less than 0.05%

Frequency response: 10Hz to 40kHz

Gain: 60dB (phono, tape), 20dB (line)

Tubes: 12AX7 (ECC-83), 12X4

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