Re: High voltage capacitors in audio

I just thought I could use the 5532 instead of 5534, because I need
two 5534's (left + right channel), and 5532 is a 'two in one'.

Then the compensation capacitor (at pins 8 and 5) is not required
because compensation is internally set in the 5532.

So far so good.

As a side issue, I came across following page:
http://www.dself.dsl.pipex.com/ampins/webbop/5532.htm

Quote:

"DECOUPLING & STABILITY. 5532 and 5534 type opamps require careful
supply-decoupling if they are to remain stable; otherwise they appear
to be subject to some sort of internal oscillation that degrades
linearity without being visible on a normal oscilloscope.
The essential requirement is that the +ve and -ve rails should be
decoupled with a 100nF capacitor between them, at a distance of not
more than 2 inches. It is NOT necessary, and often not desirable to
have two capacitors going to ground; every capacitor between a supply
rail and ground carries the risk of injecting rail noise into the
ground. The main rail decouple electrolytics can be used to do the job
for several 5532/4 packages nearby, and this cost saving is an
important layout point. Likewise, it is not normally necessary to
decouple each package individually. One capacitor every few inches is
sufficient if the power tracks are of reasonable thickness. (ie 50
thou)"

So according to the author there must be a 100nF (electrolytic, he
says) capacitor between the Vcc and gnd pins of the 5532 nearby the
5532.

Has anyone ever heard of this requirement and is it a necessity? I am
just surprised it is missing in the headphone amp's circuit (there are
100nF's in the power supply).

.

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