100W Ultimate Fidelity Amplifier

I have built the preamp Apex A2 with NE5532. Sounds great, is easy to build and cheap. Super as a pre-amplifier for meters, small amps, test purposes ...
It may be that someone finds it useful.
Unfortunately, there are many different potentometers footprints and so I for myself had not the right one on the shelf. So be careful ;)

regards Olaf

Is this the non-inverting LinearPre?
 
No, this is inverting Linear Pre and since it is inverting it sounds different than non-inverting. Warmer and softer, somewhat less detailed and bright than non-inverting. Many people find it more musical than non-inverting.

Are you sure ?
You can get an inverted signal just by reversing the speaker leads and that doesn't sound any different from the right way unless you use non musical test signals.
 
Small changes to use other potentiometers.
 

Attachments

  • APEX A2 Preamp Layout.JPG
    APEX A2 Preamp Layout.JPG
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  • Preamp apex OpAmp.pdf
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Here you go.
 

Attachments

  • LinearPre iron (2).pdf
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  • LinearPre bottom silk (2).pdf
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  • LinearPre silk.pdf
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  • LinearPre Non-inverting SMD iron (1).pdf
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  • LinearPre Non-inverting SMD placement.pdf
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  • LinearPre Non-inverting silk.pdf
    15.5 KB · Views: 226