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drrogla said:Does anyone have any experience on whichone is better suited for audio aplications (preamp). Just need something with wery low noise!!!
chemelec said:The Op-Amp is only Part of the Problem.
Regular Resistors can create More Noise than the Amplifier, Especially Higher Values.
audioguru said:Hi Nigel,
You replaced 741's in the preamp with TL071's, but still had a noisy old 741 in the mixer, didn't you?
If you turn down the mixer input control and the noise goes away, you can't assume that the noise is created ahead of the input control because it presents a low impedance to the input of the 741 in the mixer, reducing its input current noise. :lol:
audioguru said:Hi Nigel,
Yeah, the TL072 is cheap and ain't perfect. Analog Devices and Linear Technology make some extremely low-noise opamps. Judging by their very high price, their yield must be low. I can picture the production line where they all cheer each week or two when they produce one IC out of thousands that actually is very low noise! I'd like to get the ones they throw away. :lol:
A factory here made way too much canned tuna fish. They couldn't sell it for years so re-labeled it as cat food and sold it overseas. It came back here re-labeled again as tuna fish. People who bought it found it to be putrid rotten.Nigel Goodwin said:assuming they have failures, they probably just label them as something else :lol:
You will often see a NE5532 as a phonograph cartridge, tape head or microphone preamp with a whopping big input coupling capacitor that takes nearly forever to charge. The low impedance of the big input cap keeps the input current noise low.