Low noise op amp

[MmmPedals]

I just did the "hi-fi mod" for a boss eq which includes replacing the noisy tl022's. I am looking for the lowest noise possible. What should i look for on the data sheet to give me this info?

[Nasse]

Check out elektor magazine summer circuits collection, intresting booststrappin crkt...

[R.G.]

I just did the "hi-fi mod" for a boss eq which includes replacing the noisy tl022's. I am looking for the lowest noise possible. What should i look for on the data sheet to give me this info?

Good intentions!

In the TLxxx family, the TL084 is the general purpose device, the TL072 is the low noise device, the TL062 is the low power device and the TL022 is an earlier family, even lower power. The obvious solution is the 072.

I'm guessing that you want not the lowest noise possible, but the lowest noise possible consistent with not redesigning the entire circuit for low noise. Those are different things. The noise generated by the circuit consists of the resistor thermal noise and any excess noise for any carbon comp devices, the noise from any active devices, then multiplied by the gain in the circuit. Active device noise consists of the internally generated noise plus input voltage noise plus input current noise, all added in an RMS way, and then amplified by the gain. Lowest noise possible will require redesigning the entire thing right down to the last resistor. Simple noise reduction will mean slapping in TL072s.

It is not possible to look at one line in a datasheet to pick the lowest noise device. "Lowest noise" is tied up in that voltage noise/current noise thing, and varies in the actual application with the rest of the circuit. In general bipolar devices give better performance where the source impedance feeding the input is low, while JFET input opamps give better performance because of their very low input current (and input current noise) when the impedance feeding the inputs is high. The darling of the old-school mixer world, the NE5532, is a great low impedance part for low noise. But its input impedance is down in the 100K range, so it's not suited for high impedance applications without bootstrapping. The JFET input parts have impedances over 100M, so they cover the high impedance range better.

[rogeryu_ph]

  R.G. is really a walking wiki electronic preacher that's what he is 
Thanks for sharing your great ideas plus contributing endlessly your knowledge with us and we trust lords knows every good deed would be rewarded 

[tubelectron]

Hello,
For very lo noise, lo distorsion and hi linearity, I use the OPA134 IC in my audio measurements devices (for example : precision microphone preamp for loudspeaker response curve measurements).
A+!

[rogeryu_ph]

I just did the "hi-fi mod" for a boss eq which includes replacing the noisy tl022's. I am looking for the lowest noise possible. What should i look for on the data sheet to give me this info?

Though I might share but not to say your modification on your boss eq even using the most low noise chip just great co'z any noisy pedals like distortion pedal comes in or comes out from your modded Eq might be just the same only that if your plan is solely just to use only the Boss Eq alone will be great. Now i'm not saying get a noise suppressor like Boss Ns2 but it might truely help because i'm using DOD eq with Disto and NS2 and other more pedals in chain and get satisfying result even not 100% bullet vest proof co'z the entire chain plus your guitar pickup and cables up to your guitar amplifier out to your speaker inherently all these things up. Mine advise was not to discourage your ideas and wait other to give you more great suggestion  my friend.  Just sharing my experience.