Roland - AP-7 Jet Phaser  [schematic]

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Re: Roland - AP-7 Phaser

Postby RWalleyTX » 07 Jan 2018, 08:36

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Re: Roland - AP-7 Jet Phaser

Postby nechelovechek » 12 Feb 2019, 21:22

Hi. Greetings from Russia. Its a great forum you have there.
I've tried to build that phaser for a long time. It works now somehow, but the output of the effect is very low. Amplitude of the output is 4 times smaller then input. What might be tweaked to make it sound louder? I've used shematics in the attachment.
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Re: Roland - AP-7 Jet Phaser

Postby Fender3D » 12 Feb 2019, 23:33

Hi and welcome to the forum,

you're asking what to tweak to make it sound louder.... well actually, the phaser part has a low input impedance, then, if you're connecting it to a high impedance source, like guitar or bass, it should "dull" your sound with a slight volume loss. I'd add a small buffer (just a FET or BJT stage) in front of it.

IC3b and IC1d have a gain ~3 which should recover any loss in the passive output mixer...
So I would say: there's nothing to tweak... check for resistors values, solder joints or eventual short or track cut (assuming your PCB is correct...)
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