ck 2496
i keep forgetting to post this. one of the simplest
ways to build a phantom power is to wire a number of
nine volt batteries together 5 of them will do. it is
larger than doing it with two nine volt batteries, but
it is a great deal more efficient so you actually save
money buying batteries, and it is probably the
quietest thing you can do. two 1 per cent metal film
resistors of about 6.8 k, to 100 mfd 50 volt
capacitors and two 1 mfd film capacitors in parallel
is all it takes.
umashankar
--- Klas Strandberg <> wrote:
> Just add: I have been working with electronics since
> 1982. I have learned
> that it is really difficult to weight together
> different peoples
> experiences of some device.
> This is not only a problem caused by everyone's
> subjectivity, but also a
> technical. Just remember that standard components,
> capacitors and
> resistors, might have a +/- 20% tolerance. Suppose a
> condensor (whatever)
> of one power supply is -20 % and another +20%? Will
> they both work at -20
> centigrade??
>
> We naturesound people run constantly into problems
> which no one else
> bothers much about. We often work "on the limit" of
> what a product is meant
> for.
>
> Klas.
>
>
>
>
> At 12:22 2005-11-24, you wrote:
> >Yes, you are right in a way - Sennheiser made their
> own power supplies etc.
> >To make a good power supply is difficult.
> >But with new IC's, it is easy to make a lot of
> shortcuts. Then you can also
> >make a cheap power supply, with uncertain
> reliability.
> >However, my old Tascam DA-P1 has such a simplified
> power supply and it has
> >never caused any problems...?
> >
> >Klas.
> >
> >
> >
> >At 04:47 2005-11-23, you wrote:
> > > >According to my friend it is more or less by
> chance all the time if a
> > power
> > >
> > > >device works or not. He says that all modern
> IC-circuit for the purpose
> > > >have a tendency to drift away in frequency. In
> his experience only one of
> > > >them work under all circumstances, stable and
> pure. In his opinion, the
> > > >Rolls is a very conventional and thereby
> unreliable device. ... if it
> > > >works, it works... kind of.
> > >
> > > >Klas.
> > >
> > > >Does the phantom power supply he's designed
> produce less noise? Are
> > > >you free to tell us more? Is it portable? What
> operating voltage?
> > >
> > > >Rob D.
> > >
> > >
> > >Hi Klas,
> > >
> > >
> > >
> > >Isn't what you are getting at is that the Rolls
> might accidentally coincide
> > >with the correct powering voltages on some
> microphones?
> > >
> > >
> > >That to be certain that you are providing the
> correct voltages the
> > >manufacturer would be wise to supply the mic with
> the correct phantom power
> > >unit, just as Neumann has always done?
> > >
> > >
> > >By saying if the Rolls works, it works by chance?
> and should not be
> > >considered unless there is evidence providing
> it's powering that microphone
> > >model accurately?
> > >
> > >
> > >
> > >
> > >Best,
> > >
> > >
> > >Mark
> > >
> > >
> > >[Non-text portions of this message have been
> removed]
> > >
> > >
> > >
> > >
> > >"Microphones are not ears,
> > >Loudspeakers are not birds,
> > >A listening room is not nature."
> > >Klas Strandberg
> > >Yahoo! Groups Links
> > >
> > >
> > >
> > >
> >
> >Telinga Microphones, Botarbo,
> >S-748 96 Tobo, Sweden.
> >Phone & fax int + 295 310 01
> >email:
> >
> >
> >
> >
> >
> >"Microphones are not ears,
> >Loudspeakers are not birds,
> >A listening room is not nature."
> >Klas Strandberg
> >Yahoo! Groups Links
> >
> >
> >
> >
>
> Telinga Microphones, Botarbo,
> S-748 96 Tobo, Sweden.
> Phone & fax int + 295 310 01
> email:
> =20
>
>
>
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--------------------------------------------------------------------~->
>
>
> "Microphones are not ears,
> Loudspeakers are not birds,
> A listening room is not nature."
> Klas Strandberg
> Yahoo! Groups Links
>
>
>
>
>=20
>
>
>
=09
=09=09
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