Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: tubenit on July 27, 2021, 04:36:29 pm

Title: DPDT & SPDT to Hoffman relay switching
Post by: tubenit on July 27, 2021, 04:36:29 pm
I thought this might be useful to someone.   I use midboost, PAB (preamp boost), Plus-Normal, Clean to OD, and will be trying out Jazz/Rock switching.


I typically think about this and draw them up using a mental picture of mini-toggles that are DPDT or SPDT.  Then I redraw them using the Hoffman style relay switching.


CHECK for ERRORS in the drawings.  IF you find any, please post a corrected version on this thread.  With the exception of the jazz/rock switch, I have these currently active in my amp builds.


Hoffman relay information with schematics, layouts, photos, etc............. can be found in ARCHIVES here:  Relay circuit & layout board & ft switch (el34world.com) (https://el34world.com/Forum/index.php?topic=14348.0)


I have found Doug's relay switching to be super quiet and very effective and reasonably easy to wire up.


These are just a few examples of how his relay switching can be used.  Obviously, there are many other ways to use it. Essentially, anything for switching on a SPDT or DPDT, I think could be converted to relay switching.


With respect, Tubenit
Title: Re: DPDT & SPDT to Hoffman relay switching
Post by: EL34 on July 28, 2021, 02:07:59 pm
Nice Jeff!