Re: 553x opamps

[Pooh Bear]

Richard Crowley wrote:

> "Pooh Bear" wrote ...
> > More recently I saw some problems with Indian manufactured
> > MJ15003 and 15004s. Died if you looked at them wrong. Totally
> > different technology from the original.
>
> Or perhaps the problem is counterfeiting? (Re-branding after the
> fact.) Appears to be rather common for certain numbers.

Goodness knows.

Never trust Indians !

The company making them was MOSPEC. Profusion briefly distributed them
in the UK ( in good faith no doubt ) but have withdrawn the line.


Graham

[ulysses]

Pooh Bear > wrote:

>The ultimate performance from a true original 5532 or 5534 is influenced too by
>pole-zero compensation around the feedback.
>
>Neve wrote an internal application note on how to get the best results.


Sorry to dig up an old thread, but what did this Neve internal application note
say? If you have trouble, make the feedback cap bigger?

ulysses

[Pooh Bear]

ulysses wrote:

> Pooh Bear > wrote:
>
> >The ultimate performance from a true original 5532 or 5534 is influenced too by
> >pole-zero compensation around the feedback.
> >
> >Neve wrote an internal application note on how to get the best results.
>
> Sorry to dig up an old thread, but what did this Neve internal application note
> say? If you have trouble, make the feedback cap bigger?
>

Nope. Pole zero compensation.

For most cases IIRC with feedback R <= 10k put ( 510R + 22? pF in series ) in
parallel with the feedback R.

Graham

[R. Foote]

> For most cases IIRC with feedback R <= 10k put ( 510R + 22? pF in series ) in
> parallel with the feedback R.
>
> Graham

This is for lower than 10K feedback resistor? If so, what for 10K feedback resistor?

Thanks

[R. Foote]

(R. Foote) wrote in message >...
> > For most cases IIRC with feedback R <= 10k put ( 510R + 22? pF in series ) in
> > parallel with the feedback R.
> >
> > Graham
>
> This is for lower than 10K feedback resistor? If so, what for 10K feedback resistor?
>
> Thanks

Sorry, I guess it was a brain fart... Less than or equal to 10 K
Ohms. Thanks for the info Graham.

[Paul Gold]

(David Satz) wrote in message >...

> I was an acquaintance of the late engineer David Hancock, who if I recall
> correctly was a long-time friend of Peter Bartok's--though of course
> David used that degenerate form of recording known as "stereo"--perhaps
> Bartok considered that a betrayal of sorts?


I am in the process of restoring David Hancock's lathe. It is an
Neumann AM132 and had an Ortophon cutter head and tube electronics.
There is a partial Neumann VG66 rack that might be used if it can be
made un partial.

[Paul Gold]

(David Satz) wrote in message >...

> I was an acquaintance of the late engineer David Hancock, who if I recall
> correctly was a long-time friend of Peter Bartok's--though of course
> David used that degenerate form of recording known as "stereo"--perhaps
> Bartok considered that a betrayal of sorts?


I am in the process of restoring David Hancock's lathe. It is an
Neumann AM132 and had an Ortophon cutter head and tube electronics.
There is a partial Neumann VG66 rack that might be used if it can be
made un partial.

Paul Gold
Brooklynphono