Actually I take back that thing about the third diode, just the pulldown
resistor should fix things.

Bob

On Tue, Mar 17, 2015, at 09:46 PM, Bob Blick wrote:
> Hi Ryan,
>=20
> The LM358 will require a pulldown resistor on its output, otherwise it
> runs class B and will distort real bad.
>=20
> Also you will need to get the bases of your transistors a little further
> than 2 diodes apart. Put a third diode in there, and it should sound
> great but use too much current. Make that third diode a Schottky and you
> should be golden.
>=20
> Cheerful regards, Bob=20
>=20
> On Tue, Mar 17, 2015, at 09:36 PM, Ryan O'Connor wrote:
> > Hi guys, I've bread-boarded the following circuit, but its not playing
> > audio. I get only DC current at the base of the 2N4401. I've had it
> > playing audio briefly while screwing around. For example if I remove
> > the 0.01uF cap from the non-inverting input of the left-most opamp and
> > plug it back in, I hear a distorted version of the song I am playing
> > as input for about half a second (actually the cap value is polar
> > 47uF). Then silence, DC voltage. Could it be because I am using
> > electrolytics for these two caps? I can't find any "103" bipolar lying
> > around, or even close to it. I tried a 0.47uF bipolar but I only hear
> > about 0.05 seconds of audio when I plug/unplug that one. Have double
> > checked all the wiring twice.
> >=20
> > Circuit below:
> >=20
> > http://www.techlib.com/electronics/graphics/audioa14.gif
> >=20
> > Cheers,
> > Ryan

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