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Equipment file · Valve power amplifier kit

Mark III amplifier

Dynaco · 1957

Evidence status · documented

Identity and core specifications are documented; some historical fields remain unavailable.

The Dynaco Mark III was a 60-watt mono valve amplifier introduced in 1957, upgrading the Mark II with 6550/KT88 output valves and the Z-216 output transformer. It was sold as a kit or factory assembled.

Introduced
1957
Category
Valve power amplifier kit
Intended use
Mono power amplifier, kit or assembled
Production
Dynaco, Philadelphia, from 1957

Equipment photographs · 1

Dynamk3roger

1 / 1 · Dynamk3roger

Dynamk3roger·Travpeter·Public domain

Why it mattered

  1. 01

    Dynaco's kits put high-quality valve amplification within reach of hobbyists and small venues.

  2. 02

    It gave budget systems meaningful clean power.

Engineering record

Power
60 watts rated[1]
Distortion
0.5% or less at 60 W, 20 Hz–20 kHz[1]
Valves
Two 6550 (KT88), 6AN8, GZ34 rectifier[2]

Original pricing

$99.95 kit / $129.95 assembled (1965)

2026 equivalent

≈ $1,060

Period US list or retail price reported by the cited source.[3]

Estimated in 2026 US dollars using the BLS CPI-U annual average for 1965 (31.5) and 334.980 for 2026, rounded to the nearest $10.[4]

Use in the field

No named deployment could be tied to this exact item by a checked source yet. Know of one? Suggest it on the contribute page.

Manuals & original documents

No authoritative manual or original document has been located for this profile.

Sources

  1. 1Specifications of DYNACO Mark-IIIaudio-database.com · reference
  2. 2Dynaco Dynakit Mk III manualHiFi Engine · manual
  3. 3Dynaco vacuum tube amplifiers brochureDynaco (archive) · brochure
  4. 4CPI Inflation Calculator methodology and CPI-U dataU.S. Bureau of Labor Statistics · reference · 2026

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