OTL Asylum OTL, Output Transformerless Amplifier User Group.

---

[ Follow Ups ] [ Post Followup ] Thread: [ Display  All  Email ] [ OTL Asylum ]

---

[ Alert Moderator ]

---

Re: Otl which one .......

Posted by Lew (A) on January 16, 2007 at 14:48:04

In Reply to: Re: Otl which one ....... posted by freder on January 16, 2007 at 12:11:39:

The 2A3, 300B, and most other triodes, tetrodes, or pentodes commonly used as output tubes in transformer-coupled SET or PP amplifiers, are totally unsuited for use in an OTL, because they tend to have a high plate resistance, which would result in a very high output impedance of the amplifier such that it would not be suited for driving any speakers available in the real world. In fact, that's WHY one needs an output transformer on conventional tube amps. The 6AS7, 6C33C, and a very few other triodes are suited for use in an OTL because they have low Rp such that parallelling several of them results in a low-ish net output Z. EL509, 6LF6, and a few others are suitable for Futterman amps. 6C19PI may be a Russian equivalent of a 6AS7; I can't recall, but I'm sure someone will correct me on that.

This post is made possible by the generous support of people like you and our sponsors:

Schiit Audio

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]

---

[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]

---