Op Amps good to have at home in your box

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For input buffer: high input impedance of JFET input op-amp. LF353 is better than TL072 and is still cheap.

For gain stage, buffered at input and output: low noise opamp is cheaper when BJT input (NJM2068, NE5532).

Output: anything with high output current or capability to drive 600 Ohm. Cheap are 4560, 2043, etc.
 
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4558's, TL071/72, NE5532 and 741's will let you experiment with most projects whether they be audio or not. They are cheap and its no big deal if you damage any of them.

Specific projects when finalised can have the choices narrowed down to more suitable (better) devices.
 
OP134 is of course a good contender.

About output current
OPA134 like 35mA
NE5534 like 38 mA
TL071 found a figure of only 10mA, but that seems low to me
LF353 like 20mA

I will have a look at LF353 and 4558
741 is dead cheap, can do some 'dirty' work
 
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About output current
OPA134 like 35mA
NE5534 like 38 mA
TL071 found a figure of only 10mA, but that seems low to me

Opamps, contrary to theoretical believe, have difficulty driving "loads". Most of those specified to be able to drive 600 Ohm with low distortion (no more than 0.1%) will usually show clear audible difference (even if only driving a power-amp).

Unfortunately, those which can drive, have issues somewhere else (except for ultra expensive ones).

OPA2134 has difficulty driving 600 Ohm. But for LF it is okay.
 
For quick prototyping: tl071-tl072-tl074 and ne5532-ne5534.
For small usable projects: opa134-opa2134 and ne5532-ne5534.

Preferably in dip package if no pcb is available.

@johnego: it's a pity TI discontinued the lme49713. It was great on low impedance loads: THD+N, f = 1kHz (AV= 1, RL= 100Ω, VOUT= 3VRMS): 0.0006% (typ). The lm6171 is pretty good but is more sensitive to capacitive loads.
 
4558's, TL071/72, NE5532 and 741's will let you experiment with most projects whether they be audio or not. They are cheap and its no big deal if you damage any of them.

Specific projects when finalised can have the choices narrowed down to more suitable (better) devices.
yes! :) I would like to add LM358 to that list. Its common mode range extends to V- which makes it useful for single supply circuits. It is cheap, reliable and easy in behaviour too. ;)
 
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Not cheap but not expensive either. I bought quite a few LM4562's so that I could get the 10+ price break. I also have some opa2134s (which are very well behaved) and probably some tl074's.

I have some opa2604's but they did not work well in the circuit I bought them for (FDNR). The opa2134's and LM4562 both work fine.

Tony.
 
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Here's an LM358 connected as an inverting amplifier with a gain of -1.0 . Input (top) is a 5 kHz sinewave that swings between -4V and +4V. Power supplies are ±10VDC. Output (bottom) shows the severe crossover distortion that has made the LM358 infamous. DON'T USE LM358 FOR ANY SIGNAL WHOSE BANDWIDTH EXCEEDS 1 HERTZ.

If you post the internal, transistor level schematic of the LM358, I will help you draw a red circle around the portion of the design that is responsible for its (intentional!!) severe crossover distortion.

_
 

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I have some opa2604's but they did not work well in the circuit I bought them for (FDNR). The opa2134's and LM4562 both work fine.

I just checked your circuit. Your power supply is +/-10V. Even with +/-15V, OPA2604 performance is unacceptable. It needs higher rail to perform (that's why it is often lost in an op-amp rolling).

ADD:
And have you checked OP275? It's another underdog op-amp because it doesn't perform well in a conventional circuit.
 

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As long as the output doesn't have to swing too close to the negative supply rail, it is easy to get the LM358/LM324 output stage to work in class A by adding a resistor or current source to the negative rail. Even then it's not a very good op-amp.

The TLE207x series has a silly bug: when the output clips to the negative rail, the supply current increases a lot, see figure 43 of the datasheet http://www.ti.com/lit/ds/symlink/tle2071.pdf . That's something you have to be very aware of when you want to use one with a shunt regulated supply, like a resistor-Zener diode supply. Comparing the internal schematics of TL07x and TLE207x, you see that TI forgot one diode in the TLE207x series, one that should pull down the base of Q22 when Q26 is about to saturate.
 
I lean on to buy me some OPA134.
As I said earlier I want single opamp - not a dual package.
But at my dealer LME49710 is a bit cheaper than OPA134.
OPA134 cost 32 swedish crowns SEK. 10pcs 28.80/each
LME49710 cost 29 swedish crowns SEK. 10pcs 26.10/each

What would you say about LME49710?
Compared to OPA134?
 
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