4053 feedthrough

[Sean Bartholomew]

i am switching audio via a MOS 4053. problem is that in the OFF mode
there is a crackly channel off feedthrough somewhat ugly. is there a
similar chip that handles more headroom? i tried grounding the signal
through various resistors to lower the overall signal INTO the chip
but its changing the tone. im actually using a guitar as the audio
source.
the guitar is wired both directly to the OFF pin of the 4053 switch
and to the in of my overdrive FX pedal. the ON pin takes the output of
my pedal. the com/out goes to my amp.

 

[Andreas Broch]

Have you remembered to DC shield the line with a say 10 uF capacitor? That
could help. Both on the in and out of your switch.

 

[Glenn Gundlach]

i am switching audio via a MOS 4053. problem is that in the OFF mode
there is a crackly channel off feedthrough somewhat ugly. is there a
similar chip that handles more headroom? i tried grounding the signal
through various resistors to lower the overall signal INTO the chip
but its changing the tone. im actually using a guitar as the audio
source.
the guitar is wired both directly to the OFF pin of the 4053 switch
and to the in of my overdrive FX pedal. the ON pin takes the output of
my pedal. the com/out goes to my amp.

I'll bet that you're sending too much signal to the 4053. When the
signal gets near the power supply voltage, it goes through an 'off'
swich, probably using the internal protection diodes as the path. A
look with a scope would definitely confirm it.
GG

 

[Sean Bartholomew]

i KNOW its because of too much signal going in. i SAID that.
anyway for others with a similar problem, i fixed it.
Ve was set to ground and anytime the signal went below that it bled
through so all i had to do was set Ve to -5V. actually in my case
since i only had a 9V supply, i split the voltage sending 4.5 to the
circuit and -4.5 to that pin. worked like a charm. no bleed through at
all!!! even from the FX output with the overdrive volume set to FULL.
beautiful. thanks to Dwane in Canada.
thanks man!!!!

 

[Glenn Gundlach]

i KNOW its because of too much signal going in. i SAID that.
anyway for others with a similar problem, i fixed it.
Ve was set to ground and anytime the signal went below that it bled
through so all i had to do was set Ve to -5V. actually in my case
since i only had a 9V supply, i split the voltage sending 4.5 to the
circuit and -4.5 to that pin. worked like a charm. no bleed through at
all!!! even from the FX output with the overdrive volume set to FULL.
beautiful. thanks to Dwane in Canada.
thanks man!!!!

Where, sir, did you say the signal was too loud? I looked at your
original post and you said you tried resistors that changed the tone.
Nothing was mentioned about the bad sounds going away.
GG

 

[Sean Bartholomew]

huh?
ur losin me man.
anyway. the reason i used resistors was to try to GET the volume lower
so it WONT bleed through. but i works fine now. plus now i dont even
need to regulate the 9V down to 5V. i just split it to +4.5 and -4.5.
easy as peasey.