[Elecraft] AF1 Audio Filter Question

[Gary]

I use an AF1 for better volume and tone control of a VHF/UHF transceiver's
audio but I first removed the ring contact from each phone jack (their side
covers pop off easily) then when I installed the jacks to the PCB I also
soldered a short wire jumper from each tip pad to its mating ring pad on the
bottom of the PCB. This results in no modification to the PCB yet I can plug
in a monaural phone plug from the radio and a monaural speaker and it all
works fine.
Gary
N6LRV

-----Original Message-----
From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Paul Clay
Sent: Saturday, December 28, 2013 12:32 PM
To: elecraft at mailman.qth.net; don at w3fpr.com
Subject: Re: [Elecraft] AF1 Audio Filter Question

Hi, Don.

I thought to swap the headphones around to see if it might be my hearing in
one ear; the reduced output swapped to the other ear.  Will check using
other sound sources to see if it might be the phones themselves.

What's confusing me a bit is the distortion that's introduced by plugging in
a monaural plug feeding speaker all the way.  It's a scratchy sound that I
can make go away by reducing the volume control on the radio providing the
audio in to the AF1 - I'm driving the AF via my Icom R-75s external speaker
port, the receiver's headphone jack or rec line out - but then the AF1s
audio output is too low to be enjoyable.

Suppose I could just do a mod to replace the AF1's stereo out jack with a
monaural one, and then using an adapter plug between the output and my
stereo phones, but would like to leave the AF1 unmodified if possible.

R,
Paul N6LQ