AI6YR Ben3d ago

Random electrical engineering question. I am looking at building an RIAA preamp (for a record turntable), and most of the circuits out there use a NE5532 dual low noise opamp.

However, I have a LOT OF 4741 opamps (a lot). Originally destined for the L1011 aircraft, lol.

My analog design skills having significantly atrophied since college (cough cough), what specifications on an opamp (aside from noise) are important for this stuff? I suspect I have to re-calculate gain and values for a different opamp? (also, bandwidth on the 4741 is 2.5Mhz... NE5532 is 12Mhz... so I assume they aren't going to be equivalent).

#electronics #opamp #amplifier

Show threadcpm2d ago

@ai6yr
lol

used to be:
"go to the bookshelf."

&
fwiw

honestly?
stick with the 5535
*if* the goal is riaa preamp

if the goal is build the right thing with the wrong parts, ,

hehe,

well

that's way more fun!

enjoy

Show threadcpm2d ago

@ai6yr
gonna do a PS

the ubiquitous riaa preamp is well defined.

the specs matter.

can--if desired--just skip using ICs altogether, and deep dive into oldschool

biased transistors and all that.

or worse:

look at ancient neumann & altec tube amp schematics

lol!

Am very curious about the project goal.

&

dynamic or moving coil?

brand nu kettle-o-fish

of course:
the old 'just strip the circuitry out of a curb discard/dumpstered bit-o-kit'

Show threadAI6YR Ben

@cpm Well, project goal was "hmm, maybe I can built a preamp instead of buying one" *AND* "I have this big pile of OPamps and stuff in the garage".

A *very* sensible person would pay $50 for a prebuilt preamp from Amazon or eBay.

A more sensible person might buy a kit off eBay to build a preamp with a circuit board and all the parts.

I am neither! So... maybe will build one. TBD. The main issue, of course, is the time investment.

Jun 23 at 4:01pmWeb
Show threadcpm2d ago

@ai6yr
sheesh

yeah

time

we learn by doing,
not by buying

Me?

not gonna even talk about the boxes of kruft taking space in 'the garage'

I feel the clock ticking

I'm confident you do as well.

"It is written:

The camel loaded with books,
is neither a wise man nor a scholar.

For one
Can not know
without
Action."

Show threadAI6YR Ben2d ago
@cpm Yes! Learn by doing... I will learn a lot more by building it than buying it, for sure. Buying (even a circuit board which you solder yourself!) does not give you the same value. ie understanding fully what is going on and how things are connected.
Show threadcpm2d ago

@ai6yr
fwiw

I've a big(fsvo) box of old sowter & jensen audio transformers 'in the garage'

why?

because:
"ICs"

Me?

I remain unconvinced as to the superiority of semiconductors (and the requisite biasing)

for no particular reason.

Show threadAI6YR Ben2d ago
@cpm 😂