Chip rolling Newbie

WireNut · « **on:** 28 Sep 2012, 06:55 am »

I am considering changing the six NE5532 opamps in my MF X-DAC V3 to LT1057 opamps.
Are the LT1057 opamps a direct replacement for the NE5532s and would they be an upgrade?
This will be my first Chip rolling mod and I appreciate your opinions and advice.

Steve

*Scotty* · « **Reply #1 on:** 28 Sep 2012, 01:47 pm »

I would recommend an OPAMP with better than 30v/us slewrate.
As a rule they sound better and you are less likely to have slew induced distortion.
Scotty

*Scotty* · « **Reply #2 on:** 28 Sep 2012, 03:28 pm »

I would recommend a LT 1357, 25MHz 600v/us.
This is what I have in my phono stage. It is a very low noise OPAMP with very good resolution excellent frequency extension at both ends and wonderful 3 dimensional imaging.
Scotty

Davey · « **Reply #3 on:** 28 Sep 2012, 05:42 pm »

Steve,

I would be careful swapping in op-amps with much greater bandwidth. Stability issues may arise and those might translate to subjective differences that are misunderstood. You'd need some decent test equipment to find these possible issues.

The NE5532 is a superior design op-amp that works well in a wide variety of circuitry. Objectively, I don't think you will improve on its performance.

However, if the only evaluation will be subjective then it's pretty much a crap shoot. Go for it and try a whole bunch of different dual op-amps. There are hundreds of candidates.

Cheers,

Dave.

*Scotty* · « **Reply #4 on:** 28 Sep 2012, 06:43 pm »

Depending on the circuit design you may or may not have stability issues, but you can damn sure do better than a 35 year OPAMP design whose best descriptor is inoffensive.
If you check out DIY Audio forum, you may find out more about newer low distortion OPAMPs.
Scotty

Davey · « **Reply #5 on:** 29 Sep 2012, 12:53 am »

Measurable distortion is low enough and bandwidth sufficient enough for even basic (cheap) op-amps to be suitable for the vast majority of audio circuits. Much more important is associated circuit design, pcboard layout, etc, etc.

There are a thousand threads on DIYaudio.com regarding various op-amps. Reading even some of them would be a chore and leave you beating your head against the wall.

Anyways, in my opinion, "op-amp rolling" is a subject not on-topic for The Lab.....since the "rolling" seems only to be judged by subjective evaluation exclusively. And even then not a blind evaluation.

Cheers,

Dave.

Ethan Winer · « **Reply #6 on:** 29 Sep 2012, 04:22 pm »

Quote from: Davey on 28 Sep 2012, 05:42 pm

The NE5532 is a superior design op-amp that works well in a wide variety of circuitry. Objectively, I don't think you will improve on its performance.

Agreed. If the goal is low distortion and minimal coloration, then "inoffensive" is a compliment.

--Ethan