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Hoffman Amps Forum image Author Topic: Useful References to Check Before You Post  (Read 37289 times)

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Offline Fresh_Start

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Useful References to Check Before You Post
« on: March 25, 2008, 09:20:18 am »
Please let me know by PM if any of the links stop working or if other sites should be included. - Chip

Start here first - Hoffman Amplifiers Library of Information

All members need to read the info on the library pages. Many questions can be answered in the library and it's on line 24/7 with no waiting.

This is the forum search S E A R C H



How to trace out a circuit problem by Doug Hoffman in the Archives

Tube Amp Debugging Page from GeoFEX by R. G. Keen



Forum Info
Also, please look in the  ARCHIVES.

FAQs from the Archives

Forum thread on Estimating an Amp's Wattage



SCHEMATICS

EL34World Schematic library

Schematics & Layouts section of this forum which are editable!

The Fender Amp Field Guide includes speaker & cabinet info as well as schematics

Steve Aloha's schematic links

Prowess Miscellaneous Schematics including Soldano, Harmony, Laney & others

You can fine tons of good info on Marshalls and other amp manufacturers as well at Dr. Tube




Tube Data Sites
Frank's Tube Data Search

Duncan's Tube Search



GENERAL REFERENCES:

How_Vacuum_Tubes_Work.htm

Tubes for Dummies explains the jargon for basic tube circuits

Basic Electronics Concepts

Musical Note Frequencies

Exploring Electrical Engineering

Electronics for Physicists  (might not be as intimidating as the title suggests... )

Excellent Glossary of Amp terms from Randall Aiken.

Aiken's Technical Notes are a great reference.   

So are Paul Ruby's notes

There's a great introductory document on the basic theory needed to understand tube amps over on AX84.com:  P1 Theory Document

Jack Darr's Electric Guitar Amplifier Handbook is a more indepth theory document.

How To Screw Around With Your Tube Loadline

The Valve Wizard's site offers some useful theory discussions

Great source for old books on vacuum tube electronics: Pete Millett's site.

Basic theory: 
Radiotron Designer's Handbook (3rd edition) - 15+ mb
Radiotron Designer's Handbook (4th edition) - 24+ mb
« Last Edit: July 12, 2017, 02:59:30 pm by EL34 »
Quote from: jjasilli
We have proven once again no plan survives contact with the enemy, or in this case, with the amp.

Quote from: PRR
Plan to be wrong about something.

Offline Fresh_Start

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Re: Useful References to Check Before You Post
« Reply #1 on: April 03, 2008, 10:05:40 am »
A "new" general reference (Feb 2010):  P1-Extreme Theory Document

USEFUL REFERENCE BOOKS:

Please check "DVD's/Books" below for references which Doug Hoffman sells

Pentode Press for Richard Kuehnel's books on poweramps, preamps, the 5F6-A, tutorials, etc.

Kevin O'Connor's The Ultimate Tone series and other books (also available at AES).

OTHER FORUMS:

AX84 an ongoing series of single-ended amp projects with great documentation and support

Please note that you must register first to enter any of the next three forums:  
http://www.ppwatt.com for push-pull amp designs

http://www.sewatt.com/forum for single-ended amp designs,

http://www.18watt.com/ *down temporarily*

AMPAGE forum

For D'Lite info: http://ampgarage.com/forum
or the Brown Note D'Lite forum

How could I forget The Fender Discussion Page?

Sacrilege perhaps, but here's a Solid State Guitar Amplifier forum.  There's a downloadable book on solid state guitars in the first sticky thread under "Amplifier Discussion" which looks pretty good to this FNG in terms of things solid state.

OTHER MISCELLANEOUS LINKS:  

Pentode Press site has links to books, etc. plus some neat calculators there too.

Duncan's free software - the Tone Stack Calculator is great.  I still haven't figured out how to use the PSU power supply simulator but it's there:
http://www.duncanamps.com/software.html

Some good info on TONE STACKS:
http://amps.zugster.net/articles/tone-stacks

editable schematics of tone stacks courtesy of:
Tubenit

Duncan Amps tone stack discussion

Here's another wealth of info:  http://www.audiophool.cjb.net/Techno.html

This site has some useful information about how different sections of the typical Fender amp works and how to modify those.
Tone Lizard Odds & Mods.  Here's his home page as well:  
http://www.tone-lizard.com/

Blue Guitar:  articles

Here's a couple more informative sites from Sluckey:

Viva Analog   http://www.lynx.bc.ca/~jc/index.html

Navy Electricity and Electronics Training Series
http://www.hnsa.org/doc/neets/mod10.pdf

Sluckey's homepage has great info on his builds:
http://home.comcast.net/~seluckey/amps/index.htm

Here are a few other bookmarks that may be helpful:

http://www.geofex.com/gtramps.htm

http://www.geofex.com/tubeampfaq/taffram.htm

OSCILLOSCOPES:

The (Incomplete) Idiot's Guide to Oscilloscopes courtesy of the Tone Lizard

Basic tutorial for setting up and using an oscilloscope.  Also Using An Oscilloscope

AMPAGE thread on oscilloscopes - reply #4 has links to four or five other useful threads.

Last but perhaps not least, some help with
SOLDERING:

Soldering tutorial

Soldering 101

Better Soldering from Weller

NASA soldering standards
« Last Edit: March 14, 2013, 10:16:42 am by Fresh_Start »
Quote from: jjasilli
We have proven once again no plan survives contact with the enemy, or in this case, with the amp.

Quote from: PRR
Plan to be wrong about something.

Offline Fresh_Start

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Re: Useful References to Check Before You Post
« Reply #2 on: April 12, 2008, 09:39:11 am »
CABS:  BUILDING, TOLEX, ETC.

Silvatone – an excellent example of cabinet and tolexing
http://www.silvatone.bravepages.com/18%20Watt%20Lite%20II/Build.htm

Tutorial on covering a marshal box
http://www.thegearpage.net/board/showthread.php?t=70200

Casey's Tolex Tutorial
http://s238.photobucket.com/albums/ff243/Casey4s/The%20Tolex%20Tutorial-Tolexing%20a%20Cabinet/

http://s238.photobucket.com/albums/ff243/Casey4s/The%20Tolex%20Tutorial-Tolexing%20a%20Corner/

http://s238.photobucket.com/albums/ff243/Casey4s/The%20Tolex%20Tutorial-Tolexing%20Curved%20Areas/


Soldano building amps
     Go-Kustom TV - Soldano Kustom Amplification

CALCULATORS, MEASUREMENTS AND CONVERSION CHARTS

From the nice folks at AX84, here's a really helpful paper entitled Basic Math for Tube Amp Geeks

Pentode Press Amplifier Calculators includes gain by frequency for a preamp stage, "tube specific calculators" which draw load lines for you (appeals to me!), and lots of other interesting tools.

Fraction/Decimal Conversion Chart

Doug's capacitor code chart

Capacitor Microfarad/Picofarad/Nanofarad conversion chart

Doug's resistor calculators (4-band and 5-band)

R-C Filter Calculator

L-C Tuned Resonant Frequency Calculator

Frequencies of Musical Notes for Guitar & Piano attached
« Last Edit: June 07, 2012, 12:12:09 pm by Fresh_Start »
Quote from: jjasilli
We have proven once again no plan survives contact with the enemy, or in this case, with the amp.

Quote from: PRR
Plan to be wrong about something.

Offline Fresh_Start

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Pedals etc.
« Reply #3 on: September 23, 2009, 11:40:37 pm »
Another neat resource including tutorials on soldering, parts selection, etc.  Obviously with an effects pedal slant, but lots of useful info:

DIY Stompboxes FAQs

and PLEASE let me know if any of the other links go dead...

Chip
Quote from: jjasilli
We have proven once again no plan survives contact with the enemy, or in this case, with the amp.

Quote from: PRR
Plan to be wrong about something.

Offline Fresh_Start

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  • Posts: 2856
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Re: Useful References to Check Before You Post
« Reply #4 on: September 29, 2009, 02:49:37 pm »
There is a section in Doug's Library that I didn't find for a while but is very helpful:

Hoffman Board Manufacturing Instructions

There is nothing wrong with Gabriel's approach to making a board & mounting the components.  This simply shows you Doug's method, plus his schematic/layout drawings make more sense if you walk through the instructions while looking at the drawing.

Chip
« Last Edit: September 22, 2010, 06:30:49 pm by Fresh_Start »
Quote from: jjasilli
We have proven once again no plan survives contact with the enemy, or in this case, with the amp.

Quote from: PRR
Plan to be wrong about something.

Offline Fresh_Start

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  • Posts: 2856
  • noob de Lux
Hoffman Amps Forum image
How to Bias Your Amp
« Reply #5 on: September 22, 2010, 06:36:12 pm »
HOW TO BIAS YOUR AMP

This topic comes up so often, I thought it would be helpful to have a collection of links:

Here's a great explanation of How to BIAS your amp

Of course, there's also a section in Hoffman's Library

Also, Doug now offers kits to make his bias checker.  
Just scroll down to the bottom of this page HERE.  
Link to new assembly instructions is there too.

Hope this helps,

Chip
« Last Edit: June 07, 2012, 12:14:03 pm by Fresh_Start »
Quote from: jjasilli
We have proven once again no plan survives contact with the enemy, or in this case, with the amp.

Quote from: PRR
Plan to be wrong about something.

 


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