OP amp LME49710

[goraman]

Is this a good op amp and is there a better replacement?http://www.national.com/ds/LM/LME49710.pdf


I don't know much about them.

[StanleyB]

It depends what you want to use it for, and what the operating voltage is that you are using. Many opamps are tasks and voltage specific.

[Techno Commander]

for analogue signals, I rather like the sound of the Burr Brown FET opamps.

[goraman]

That opamp is in my Little Dot DAC 1.
I just read a DYI forum post where a guy said the op amp I have was the most enjoyable so mabey I'm peeing in the wind.

[Reid Malenfant]

It all depends on the impedance of the circuit feeding the op amp & the output impedance the thing will be driving as well as intended use as to which op amp will do a better job.

Supply voltage considerations need to be taken into account as well as some op amps are only properly biased at higher voltages, lower voltages resulting in increased distortion.

It like asking what car is the best for the job when we don't know what the job is so to speak :eyebrows:

[goraman]

http://www.diyaudio.com/forums/solid-state/144192-opamp-compatibility.html


found it!

[goraman]

I think I'm looking for a solution to a non problem,wouldn't be the first time I spent time and money only to return to the point where I started out.

[StanleyB]

They are discussing the LME49720, whilst you asked about the LME49710. Would be a big mistake to mix them up. Smoke yes, mirror no ;).

[goraman]

They are discussing the LME49720, whilst you asked about the LME49710. Would be a big mistake to mix them up. Smoke yes, mirror no ;).

Reread the first post,what was the most pleasent sounding opamp of what he's tried?

[DSJR]

Resurrected from long ago, but might the 49710 be a good modern replacement for the LM301? Either this or the LM833N....

[StanleyB]

The LME49710 is the single channel version of the LME49720, which is the metal can version of the LM4562 as fitted in the Caiman SE.
The best opamp IMHO opinion is the THS4032CD, but it only comes in surface mount package.

[DSJR]

Thanks again Stan... This is for my old Crown IC150, which I'm tinkering around with. The chips on the line stage are summat like 5253??? although the manual says LM301, which apparently wasn't good enough. I'm keen to "economically" upgrade this unit and the IC's are the first port of call, together with the supply caps, which are plastic cased 470uF 35V...

http://i132.photobucket.com/albums/q8/DSJR_photos/ead9c4ee.jpg

I can't believe how simple this is, the stuff on the left is power supply and (switchable) tone controls and the gubbins in middle and right are to do with switch-on mute and the switchable filters and variable loudness contour. The few remaining bits are the line buffer IC's and associated passive components (the four 1uF tants have been changed to 1uF Wimas, as apparently the tants can give trouble when old)...

[DSJR]

Bump -

Since the LM301's here aren't used with a little cap betwixt pins 1 and 8 as they are on other devices (Sequerra tuner and some old mixing consoles), would the 49710 be a straight drop-in fit? if the bandwidth of the latter is too wide, what about the trusty OPA204?

[RobHolt]

Agree with others in that OP amps need choosing according to the task and circuit conditions.
A fairly safe but good choice for most situations is the OPA134 (dual OPA2134).
High input impedance (JFET), modest power consumption, fast but not too fast, unity gain stable and clean into reasonably low impedance loads. Unlike many modern super fast devices it doesn't usually require additional rail decoupling caps. It is effectively a much better TL071.

Bit of a tangent, but the 49710 (tin hat version) is a nice choice for Quad phono cards :)

<edit> If what you have fitted are 5532/4 then I wouldn't replace them. Still very good for audio after all these years.

[DSJR]

What's there is a 3532, which I've barely seen reference to... I suspect it's a minor move on from the LM301's it should have had?