Tube DIY Asylum: Re: Best Driver Stage for a 10/10Y by JLH Do It Yourself (DIY) paradise for tube and SET project builders.

For Sale Ads FAQ / News / Events

Posted by JLH (A ) on November 5, 2001 at 11:23:23

In Reply to: Best Driver Stage for a 10/10Y posted by Thorsten on November 5, 2001 at 09:58:12:

Thorsten,

I built a Direct Reactance Drive amp ( Monkey amp) using a 10Y and 5842 / 417A. The operating point for the 10Y is 380V from plate to cathode, grid voltage –28V and plate current of 30mA. The operating point for the 5842 is 140V from plate to cathode, grid voltage of –1.5V and plate current of 20mA. The interesting thing I did different is to select the driver’s plate current and the DCR of the reactance choke to develop the all of the negative grid voltage for the 10Y. The choke I used had a DCR of 1400 ohms, which coupled with the 5842’s plate current of 20mA gives me the grid bias I need for the 10Y. This allows the elimination of the first cathode bias resistor and simplifies the circuit even more. You are now down to two tubes, two resistors, two capacitors, one choke and one OPT. In addition, since I am running more plate current through the 10Y than what is normal, its plate resistance dropped and allowed me to use a common 5K OPT. Besides, this amp was built to only handle from 75Hz and up. I did not need the extra bass from a 10K OPT. I have not measured for distortion, but this amp has a very clean and sweet sound to it. Much different from the bloated and harmonically heavy sound of a typical 300B. Power measured 1.75 watts rms in class A1. Class A2 will net around 3 to 4 watts depending on your OPT and tube. Good luck on your amp project and keep us updated on your progress.

JLH

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

Atma-Sphere Music Systems, Inc.

---

[ 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 ]

---