questions about LM386 based distortions

[Gurner]

This is an old thread but stil intriguing i like the sound of 386 but still difficult to tame some buzz and decaying notes!
the reason i want to UP this thread is to know the answer of the .1nf and 10ohms said by PRR

The clue was in what he said...

Add the 0.1uFd 10 ohm compensation network shown on the LM386 documentation.

LM386 documentation....

http://www.biltek.tubitak.gov.tr/gelisim/elektronik/dosyalar/6/LM386.pdf

page 5 extract...



it's called a Zobel network, and there are some dodgy types who use the term proliferously in order to earn kudos....don't be fooled.

Also, if building any of the LM386 based distortion, be sure to slip into a pair of flares & sing "everybody was Kung-Fu fighting.....hooo, hah", as you solder it up.

[askwho69]

Hooohh haaah! Thank you so much! sorry cant catch simple english or miss understood some of phrases

[thehallofshields]

Okay, I know this is a dead thread,  but I'm working on a 386 distortion and I'm very interested in this Zobel Network idea.

Reading around on audio forums, I'm understanding that the Zobel Network is a R-C or C-R in series-to-ground to work some magic to smooth out the output impedance.

My questions:
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1) Is this going to make a difference if its not going to a speaker, but going into a passive volume/tone control instead?

2) This is said to increase 'stability'. Does that mean a more even frequency response?

3) Will it help the fizzy Note-Decay problem of the 386 distortion designs?

4) What will the affect of a larger or smaller capacitor be, and what capacitance issues require it to be physically close to the IC?
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I can't wait to hear what people have to say about this one!

[thehallofshields]

Searching: "Zobel Network 386" turned up Gurners' answer to (3) the fizz issue:

No $$ = Poor Sound (Page 4/5)
http://www.diystompboxes.com/smfforum/index.php?topic=87357.15;wap2

[thehallofshields]

Well I tested my question (4).

I tried alligator clipping a zobel network to my perfboard and it added some really wet high frequency gunk that sounded terrible.

Might be RF Osciallations, but the horrible wet-scramble distortion sounds just like what happened to my Boss OC-2 when I did the 'synth mod', the Flip-Flop IC in there really didn't like ANY capacitance on the output. It even came through when the pedal was bypassed.

[kingswayguitar]

hmmm
i use them with my pedals but never tested with versus without