Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

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knathan
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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

Post by knathan » Wed Apr 01, 2009 1:26 pm

Brad- this is an awesome thread/ tutorial...will come in quite handy when I begin my first attempt :ph34r:
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billaftermath
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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tutorial!

Post by billaftermath » Wed May 06, 2009 12:32 pm

I have been trying to figure all of this kind of stuff out. Just finished school for the year, so I am gonna focus on doing this for a bit.

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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tuto

Post by Keegan » Mon Aug 02, 2010 6:03 pm

Is a standby switch just a kill switch for the high voltage from the transformer so that the tubes have time to heat up before any high voltage is applied? I wanted to add one to my Blackheart since I never use the 3w/5w switch.
My Fender goes to twelve.

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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tuto

Post by øøøøøøø » Tue Aug 03, 2010 6:20 am

there are several different ways of doing a standby switch. Usually they are after the rectifier, sometimes after the first stage of filtering as well to protect tube rectifiers. Typically the switch is before any subsequent stages of filtering.

Another method is to use it to lift the center tap of the high voltage winding of the PT.

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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tuto

Post by misterMagoo » Thu Oct 28, 2010 1:30 pm

This thread is awesome!!! It's really helping me with the mods I'm doing to my AC30!

Here is another link that may be very useful:
http://www.freewebs.com/valvewizard/" onclick="window.open(this.href);return false;
lifereformatted.wordpress.com

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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing tuto

Post by Sanibel » Mon Apr 25, 2011 8:40 am

Thanks for all of this information - it's fantastic!

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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing

Post by RaDana » Thu Jan 12, 2012 11:03 pm

I was just curious, if you wanted to lower the wattage of your amp, you would apply Kirchoff's Law (V=I/R), no? Lets say you had a large transformer and wanted to step down--a 50w amp to run at 30w or a 100w to run at 50w--all you would need is a large resistance such as a large (series) of resister(s) following the transformer, yes? I understand voltage as what pushes the current through the circuit, so would this then in effect act as a yoke to prevent the amp from running untethered and destroying itself?

Hope I made my thought-process clear :jacked: ....

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Re: Tube amp schematics 101, etc: NEW NEWER UPDATE: Biasing

Post by RaDana » Fri Jun 08, 2012 9:34 pm

If it helps anyone else whose a visual learner, I found some videos that look pretty helpful.

http://www.youtube.com/user/glprecycledsound/videos" onclick="window.open(this.href);return false;

Plus when you look at the videos you can find similar videos on the right side bar.

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