diyAudio - View Profile: ballpencil
Go Back   Home > Forums > Members List
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

ballpencil ballpencil is online now

diyAudio Member

About Me

  • About ballpencil
    RF Engineer


Total Posts
  • Wiki Contributions: 0
  • Wiki Comments: 0
  • Recent Wiki Activity: ballpencil has no recent wiki activity
General Information
  • Last Activity: Today 06:59 AM
  • Join Date: 15th November 2013


Latest Blog Entry

Posted 27th May 2016 at 05:48 AM by ballpencil Comments 0
Posted in Uncategorized
This circuit is to fulfill my curiosity of hearing the sonic differences between pentode, ultra-linear and triode gain stage. As with any line stage, this circuit can also be the input part of a power amplifier. I'm considering a single ended amplifier where both the input and output stages have adjustable ultralinear percentage.. I'll show the output stage design on another post.

Anyway, i'm not sure there will be an audible difference between each mode other than gain.. but until i actually build this circuit, i can't really be sure.

The idea is to use a pot to replace R5+R6. Dual 250K linear pot should do for both channel. You then adjust the screen feedback percentage by adjusting the ratio between R5 and R6. Here's how you obtain each mode:
1. Pentode mode is by making R5 = 200k and R6 = 0R. This will keep the screen grid at at fixed voltage regardless of plate swing.
2. Triode mode is...

Posted 26th May 2016 at 06:04 PM by ballpencil Comments 0
Posted in Uncategorized
Such mouthful blog title.. The idea is nothing new: to get the so-called "tube sound" from a hybrid amp. Tube sound for me comes from these two factors:
1. Triode-like linearity
2. Low to moderate damping factor
Personally, i believe number two is the main reason for tube sound. Any solid state amplifier manipulated to get a damping factor of around 1-2, instead of the typical SS amp DF that falls into the tens to hundreds, will sound like a tube amp. This is because with such low damping factor, the amp ceases to ignore the speaker impedance curve and start to become less of a voltage source and more of a current source where the bumps of speaker impedance curve will affect the amp's output.

Without further ado.. here it is:

Some notes:
1. Ignore the transistor and MOSFET type. I chose them because that's what i have in LTSpice. The small signal BJT can use BC547 for...

Posted 26th May 2016 at 03:25 PM by ballpencil Comments 0
Posted in Uncategorized
I joined on Nov 2013 and that's pretty much when i started this hobby. Maybe "restarted" is a better term as i played with diy amps, tin and soldering iron back when in junior high but somehow stopped. That being said, it should be obvious that i am just a beginner and with that:
1. There will be mistakes/misinformation. Feel free to correct me. It will be much appreciated.
2. There is no guarantee any schematic shown works in real life, unless mentioned otherwise. Basically once LTSpice shows that it works, i'm 80-90% sure it should work in real life.
3. There will be updates and revisions as i learn more, hopefully with your help!
4. There will be language barrier. English is not my first language so bear with me!

Hide this!Advertise here!

New To Site? Need Help?

All times are GMT. The time now is 07:00 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.
Copyright 1999-2016 diyAudio

Content Relevant URLs by vBSEO 3.3.2