Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

Tecon Model "55" final mods(?)
Tecon Model "55" final mods(?)
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
Reply
 
Thread Tools Search this Thread
Old 25th April 2010, 09:06 PM   #1
4season is offline 4season  United States
diyAudio Member
 
Join Date: Mar 2006
Location: Colorado, USA
Default Tecon Model "55" final mods(?)

Click the image to open in full size.

Hard for me to believe, but I've spent almost two years of on-again, off-again work with this amp. It sure has taught me a lot about how amps work!

As delivered by the factory, the printed circuit board is laid out incorrectly, leaving the amp without functional grid stopper resistors.
Click the image to open in full size.

But I went a bit further than simply correcting the wiring error. Though the basic circuit is mostly unchanged, the "final" version of the amp features upgraded output transformers (Edcor XSE15-5K), larger cathode bypass capacitors (Elna Silmic), and most importantly, the 1k ohm metal film resistors used as grid stoppers have been replaced with carbon composition types, selected for their high frequency performance. These are placed about 1 cm away from the tube sockets for best performance. Stock 0.1uf coupling capacitors were okay, but for fun I changed these to 0.1uf 716P polypropylene "Orange Drops" which didn't make a really big difference, but it certainly didn't hurt either. Tubes consist of stock Raytheon 5755 at the input, and Russian 6P14P-ER outputs, of which I have a good-sized supply.
Click the image to open in full size.

1 kHz square wave:
Click the image to open in full size.

10 kHz: I seem to have a resonance at around 120 kHz causing the extra "blip" in the sides of the wave.
Click the image to open in full size.

20 kHz: The high frequency artifact is more visible, but should be completely inaudible. The sides of the wave are going more triangular, but all in all, I'm really pleased by what I'm seeing here.
Click the image to open in full size.

How's it sound? Wonderful! "Air" and detail, but with guts too, and the harmonic rightness you expect from single-ended, all from good quality yet inexpensive parts.

Tecon Audio Model "55" product page
  Reply With Quote

Reply


Tecon Model "55" final mods(?)Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
CROUZET-Motor for Transrotor Turntable Model "Hydraulic" - Replacement? tiefbassuebertr Analogue Source 8 17th March 2010 05:56 PM
Super Sanken Final Stage "Tauro" Stee Solid State 25 19th March 2008 08:01 PM
"More stuff" final clearance sale. Colescuttle Swap Meet 6 5th January 2007 02:29 PM
Some final pics of "Stacks" revisited and "Askew" with stand Andy G Multi-Way 2 3rd February 2005 06:07 AM
DIY "Final Scratch" Turntable DSP Ignite Digital Source 5 25th February 2002 11:52 PM


New To Site? Need Help?

All times are GMT. The time now is 03:41 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki