My problem is as in the title. Is the replacement suitable?
If yes, which one of AD8620 and LM4562 will be more
correct?
Edit. This is for my CD-player.
Regards
Roushon.
If yes, which one of AD8620 and LM4562 will be more
correct?
Edit. This is for my CD-player.
Regards
Roushon.
Exceptional quality ?
Please download /read opamp_distortion.pdf here:
SG-Acoustics · Samuel Groner · IC OpAmps
Z
Have a listen to the LM4562 here. The files are still available for now.
http://www.diyaudio.com/forums/everything-else/250149-listening-test-part-2-active-circuitry.html
Samuel tested the RC4580 which is marketed as a "drop in replacement" for
the NJM4580 but it´s _not_ the same chip.
The (original) NJM4580 is actually rather good and even used in ultra expensive
Accuphase products.
You can replace NJM2068 by LM4562. NJM4580 requires more care, usually a high-current not-too-fast FET opamp is suitable. To utilize AD8620 requires some knowledge on the circuit. If it is well implemented, non prone to oscillation, with high input impedance and within supply specs, it should work well.
Yes.
LME49860 is a candidate and it is also bipolar. It needs to be well decoupled so the PCB must have caps from + and - to GND close to the opamps.
LME49860 is a candidate and it is also bipolar. It needs to be well decoupled so the PCB must have caps from + and - to GND close to the opamps.
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I think this has all been discussed before, but comparing datasheets for LM4562, LME49720, and LME49860, they sure look strikingly similar. Main exception would be LME49860 is specified for higher voltage rails.
IME they are very good audio opamps, but a possible weak point may be their sensitivity to radiated RF. In particular, IIRC, DECT wireless phone base stations in the near vicinity (say, maybe, 10ft. or so) of an unshielded LME49720 have been observed to produce periodic FFT spurs (@ 100Hz intervals, IIRC??).
In places less hospitable to LME49720, OPA1612 has proven to be a very useful opamp for dac I/V and or differential summing.
IME they are very good audio opamps, but a possible weak point may be their sensitivity to radiated RF. In particular, IIRC, DECT wireless phone base stations in the near vicinity (say, maybe, 10ft. or so) of an unshielded LME49720 have been observed to produce periodic FFT spurs (@ 100Hz intervals, IIRC??).
In places less hospitable to LME49720, OPA1612 has proven to be a very useful opamp for dac I/V and or differential summing.
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to the original poster:
don't forget the AD8620 has lower max voltage rating than other op amps.
max is only +/- 13V vs the more usual +/- 15V.
don't forget the AD8620 has lower max voltage rating than other op amps.
max is only +/- 13V vs the more usual +/- 15V.
Hi, with a great pleasure I can reaffirm that your opinion is absolutely correct, Japanes ei Nisshinbo NJM20xx and 4580 are (although relatively cheaper) by class better products than its replacement.
Ti and others do have interest to make them at the same level as its primary production line of OPA class IC-s. Only really better substitution for NJM4580 for example as Pre-Amp can be no less then OPA2228 or even better OPA1612, but for that -3dB less noise (and distortion) over whole audio spectrum you will have to play premium extra. Avoid LM4562/LME49720 and OPA2134/2604 if you do not want to re-engineering circuitry to make it stable. Question is OPA1612 or even better if you can NJM8830. For me NJM8830 is ... better, it can really only compete with LT1028. Al of that is if you use them in pre-amp role. As exit or exit buffer Amp with low Gain NJM4580/2068 are SPOT-ON and do not touch them, although NJM8830 are even better and LM4562/LME49720 are also quite precise.
Best regards,
Yes, you are right, and I just want to reaffirm that with my latest test and measurements so nothing subjective just objective notion.
One day some new people with same dilemma and question will stumble on this post so it is good to confirm to them that nothing has changed...
I used opa1642 in 2015 though...Also read this document from 2012 : https://www.google.com/amp/s/pdfsli...g-for-ultra-low-thd-n-in-analog-circuits.html
The thread was started in 2014. In 2022 one would suggest OPA1642 and OPA1656 methinks.
Very nice presentation in the link! Thank you.
Very nice presentation in the link! Thank you.
I tried Bruce's ne5534 compensation methods though...yet couldn't hear a difference . It's very hard to ignore AP chairman's guidance though...
Why? We are all humans, no one has a patent on the truth. Did you see a billionaire making a joke with a sink last Thursday?