Vacuum Tubes for the MKIII Amplifier

Please contact us to discuss ordering.

MKIII Output / Power Tubes 

Genalex Gold Lion KT88


Sold Only in Quads, (4) Tubes - Apex matched set. Triple getters for a superior vacuum, gold plated grid wire and eye-catching gold artwork on the bulb, these KT88 have a lot of punch with great detail.

Mullard Reissue KT88


Sold Only in Quads, (4) Tubes - Apex matched set. Octal beam Tetrode, an exact copy of the KT88 valve manufactured by Marconi-Osram in the late 1960s and 70s. Powerful, balanced and detailed soundstage with full bass.

JJ Electronics KT88


Sold Only in Quads, (4) Tubes - Apex matched set. The JJ Electronic KT88 is a sonically faithful reproduction of the original tubes with a robust construction encased in a thick glass envelope. This tube has a tone that is warm and lively with a detailed and balance response.

MKIII Driver tubes

6AN8A - Triode / Pentode Driver Tube


Sold only in pairs, (2) tubes - Various quality brands like RCA, GE, Sylvania (brand selection subject to availability)

New-Old-Stock (NOS) tubes. The 6AN8A is a medium mu triode and a sharp cutoff pentode in the 9 pin miniature construction. Our amplifiers use the original Dynaco circuits, so these are the tubes you'll need for our MKIII.

mkiii rectifier tubes


5AR4 / GZ34 (U77) Genalex Rectifier Tube


Sold as each. Works in the Dynakit / Dynaco ST-70, MKIII and MKIV Tube Amplifiers. Genalex Gold Lion U77 / GZ34 full-wave rectifier tube. A highly rated indirectly heated dual diode, full-wave vacuum rectifier. This tube insures a strong, dynamic response. Excellent sound and a reliable choice, the Genalex U77/GZ34 comes with a dark blue base. It has a stable tandem supported getter cup, industrial thickness dual mica spacers and full 30mm length internal plate structures.  

5AR4 / GZ34 Tung-Sol Rectifier Tube


Sold as each. Pre-tested and burned in for quality assurance. For use in the Dynakit / Dynaco ST-70 and MKIII or MKIV Tube Amplifiers. Tung Sol 5AR4 rectifier tube is a premium grade directly heated heavy duty rectifier Diode. Helps extend the life of the other valves in the amplifier by allowing them to heat up before plate voltage is applied. 


5AR4 / GZ34 Solid State Rectifier


Works with the ST-70, the MKIII and MKIV Amplifiers. This  custom made "Copper Top" Solid State Rectifier works great. Plugs right in the socket like a tube. Includes a protective "soft start" just like a regular 5AR4 / GZ34. If you're changing from a glass tube to this solid state rectifier, your amplifier will require adjusting / re-setting the bias, as bias will typically be slightly higher with this SSR, due to it being more efficient than a vacuum tube. Reduces transformer load, runs cooler, increases bass response and improves speaker damping.