Amp WiP shot 4 by Tiido

Amp WiP shot 4


24 August 2014 at 12:43:44 MDT

This is a close up of the loudness compensation part being worked on.

I was testing various resistors to get most smoothest and seamless correction curve. eventually I found that 2.7K + 2.7K + 0.01µ = near perfection :D

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Visual / Photography


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    Loudness compensation? :P Like a power damping unit?

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      Human ears have non-linear freq response that depends on loudness of the sound. The louder the sound the less you hear higher freqs compared to lower stuff and if you don't compensate for it you get unnaturally bright sound at higher volumes. There's also some action going on at lower end when sound is quiet but that's far less unpleasant than the highs issue. Ideally bass is boosted when sound is quiet and highs reduced when it gets louder.
      Look up equal loudness contuour, it describes the problem.

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        Ah yeah I'm familiar with the concept, just wasn't sure what you meant. :P I'm a guitar amp guy, so I'm quite well acquainted with the issue. x)

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          Here it is called "tone compensation". I don't know what the proper term is in English, but I see "loudness" being used so I made some amalgamation of that LOL

          And awesome ! I used to play bass some 7 years ago. My HiFi managed really good, and holy hell how awesome it sounded when I plugged the guitar to the vinyl player input (RIAA/CCIR preamp there) hahahahaha. My parents did not like it a single bit lol.

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            Haha, I bet. I'm actually building an all tube amplifier right now! I should post progress shots.

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              Yush, you should :D