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AX84 Doberman Heyboer 20W Semi-Universal Single-Ended Tube Output Transformer EL34,6L6,6V6, KT88 etc

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AX84CH Gear
north augusta, SC, United States
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The Legendary 20W Doberman Music Products AX84 Semi-Universal Single-Ended Output Transformer (made by Heyboer Transformers in the USA) is available again for a limited time.  New 2020 USA production!

This transformer was originally designed for AX84 tube guitar amp projects like the P1, Hi-Octane, P1-eXtreme and Single Ended lead.  We designed it to have enough guts to work well with a big tube like a KT88 but still work great with 6v6 and all the other common octals like 6L6, 5881, KT66, EL34, KT77 etc...   It is up to your circuit of course.
These are rated for 18-20W audio duty.  The primary is wound with #30 wire which Heyboer said is rated for 144ma FULL DUTY or up to 190ma AUDIO DUTY.   That is enough handling to get the goody out of an octal tube in a single ended configuration.

The Heyboer output transformers were loved by people worldwide for their great tone in single ended guitar amp projects.  These are subjectively better than the common Canadian universal transformers and have that great Heyboer tone baked in.

It has multiple primaries so that you can set the primary impedance close to what you want for the tube you want:  2.5k, 4k or 6k.  If you use NFB or experience squealing, you may need to reverse your two primary wires, as is common in any output transformer installation.

It also has secondaries for 4,8, and 16 ohms. 

Specifications: 18-20 Watts, up to 145-190ma AUDIO DUTY
Wiring:   Primaries:  (Cap off any that you don't use)
  • primary Brown=0
  • primary brownn/yellow=2.5K
  • primary blue/yellow=4K
  • primary blue= 6K 
  • secondary  black=0
  • secondary yellow=4 ohms
  • secondary green= 8 ohms
  • secondary orange=16 ohms

This is intended for experienced technicians.  Please don't ask me if this will work in your amp.  I can't guarantee its fit in amps and projects I don't know anything about.

People have asked me about doing another run of these for years, so I'm offering these for people who know what they are and know what they are doing with them.  Please don't screw us both up by ordering one, deciding it isn't right for you or frying something or yourself and then trying to send it back.  Thank you!  -Chris Hurley from AX84.

This item is sold As-Described

This item is sold As-Described and cannot be returned unless it arrives in a condition different from how it was described or photographed. Items must be returned in original, as-shipped condition with all original packaging.

Product Specs

Listeda year ago
ConditionExcellent (Used)
Excellent items are almost entirely free from blemishes and other visual defects and have been played or used with the utmost care.learn more
Made In
  • United States

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