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Hoffman Amps Forum image Author Topic: Listening amp  (Read 4820 times)

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Offline mresistor

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Listening amp
« on: May 29, 2023, 02:06:57 pm »
Hi there doesn't seem to be an easy way to find the instructions for the listening amp. 

Offline shooter

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Re: Listening amp
« Reply #1 on: May 29, 2023, 03:27:49 pm »
surf up "simple headphone amplifier"  1 lm386(?), or a 2 transistor 'ol school.  the ONLY must in the design is it's cap coupled between the probe n the L-amp.  a 5F2 will work, as long as you can control volume you should be good
Went Class C for efficiency

Offline mresistor

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Re: Listening amp
« Reply #2 on: May 29, 2023, 04:33:46 pm »
surf up "simple headphone amplifier"  1 lm386(?), or a 2 transistor 'ol school.  the ONLY must in the design is it's cap coupled between the probe n the L-amp.  a 5F2 will work, as long as you can control volume you should be good


Shooter I'm referencing that the link to Hoffmans instructions on how to build the "listening probe" was moved and now there seems to be no place to find the instructions.  I built a listening probe and use it
with one of my Champs and it works well.  Where's the link mods?

Offline sluckey

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Re: Listening amp
« Reply #3 on: May 29, 2023, 05:49:51 pm »
I built a listening probe and use it with one of my Champs and it works well.  Where's the link mods?
Ask Doug. I have a lot of difficulty finding stuff on this site too.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline PRR

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Offline EL34

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Re: Listening amp
« Reply #5 on: May 30, 2023, 06:58:32 am »
Search works great
Library page - search button at top - listening amp
I found it in under 15 seconds


Offline mresistor

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Re: Listening amp
« Reply #6 on: May 30, 2023, 09:44:18 am »
Thanks Doug.. 

Offline EL34

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Re: Listening amp
« Reply #7 on: May 30, 2023, 09:45:09 am »
I built a listening probe and use it with one of my Champs and it works well.  Where's the link mods?
Ask Doug. I have a lot of difficulty finding stuff on this site too.
Search engine buttons works on both my web sites  :icon_biggrin:

Offline sluckey

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Re: Listening amp
« Reply #8 on: May 30, 2023, 09:59:13 am »
Or you could click on the 'Tube Amp Library' link at the bottom of this page. Then scroll down the page about .9 miles and click on the 'Cool amp tools' link. You may need to give your scroll finger a couple breaks before you get there. I really wish the Tube Amp Library page could be organized in a more intuitive way. Just too much info and links on that mile long page.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!


 


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