Tube DIY Asylum Do It Yourself (DIY) paradise for tube and SET project builders.

---

[ Follow Ups ] Thread: [ Display  All  Email ] [ Tube DIY Asylum ]

---

[ Alert Moderator ]

---

Re: I wanna tube! Please advise

Posted by Jenya (A) on November 2, 2001 at 12:44:09

In Reply to: Re: I wanna tube! Please advise posted by ck42 on November 2, 2001 at 12:06:31:

"This still seems weird to me, though I'm sure it will all make sense very soon. For right now, it seems like I'm amplifying a signal, and then using an AMPed signal just to run a grid on another amp...it doesn't seem doing this would server much purpose..."

It seems that you are understanding perfectly what is going on but not seeing the purpose in doing that. You can imagine that if you drive a second tube with an amplified signal, you will even further amplify that signal. Another thing is that not all tubes are designed for amplification. For example, output tubes usually don't have great amplification factor but are capable of conducting fairly high current that can be routed through an OPT. Therefore, all amplification has to be done before that stage. I am sorry, if I keep confusing you.

"I *think* it should simply be a matter of finding the right OPT with a secondary to run the cans. Or is there another (better) way of doing it?"

You could put together an SRPP preamp and use fairly big size decoupling capacitor for driving headphones. Personally, I don't like OTL (Output Transformerless) amps as much as the ones with OPTs. Nevertheless, it can sound quite well. Take a look at www.headwize.com
They have a fairly big library of hadphone amp projects. I may be wrong, but the problem that you may encounter with using preamp for driving cans is an output impedance of an amp. Generally, you want to use output tubes with fairly low plate resistance. However, it is not necceserely the case with preamp, since you are just trying to raise the voltage. To be honest, I am in the guess land right now and hopefully somebody else would be able to comment on this issue.

"BTW, your answers to my other questions were terrific...thank you VERY much."
Anytime.

Jenya

• http://home.jps.net/~jenya/hifi/headphone_amps.htm   (Open in New Window)

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

Kimber Kable

---

[ 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 ]

---