Any OpAmp Rollers Here?

Any OpAmp rollers here???

If so, and you are willing to try some op amps and post about your experience....

....please PM me.

 

I'm in remission. It was a long, long battle to become "well" again.

 

The only thing I roll is pizza dough...

 

Wasn't that guy Felix from Australia an "op-amp" roller? BTW, what the heck happened to him? He used to post here daily and now he's gone? I'm sure he'd chime in here.

 

He gets very passionate, so I think he may have left on his own, or maybe was asked to leave.

 

Yea. What happened to Felix? I rather enjoyed reading his posts. Seemed liked a likable person and I always liked fellow tinkerers. I've been so busy renovating a house it's detracted from some or most of my free time to do so. I just got to pick up my Taylor for about an hour the other day. Bliss

Shout out to you Felix!

 

I had a Heed Canamp which had a socketed IC. Originally used a 5532 I think, and then splurged ($4) for a different IC to very good effect

 

I have played around with some op amp changing in some circuits -- CD players, guitar stop boxes. In my experience the degree of change and the quality of change when swapping op amps has very much to do with the specific circuit you're using the specific op amp in. It's possible to make an op amp change that produces a barely audible change to pretty much no change at all; and its certainly possible to make a circuit that's been designed around a specific op amp sound worse by swapping op amps. People with much more experience with me will eventually chime in I'm sure; but my somewhat limited experience suggests that it's are to promulgate and hard and fast rules that X op amp sounds more one way than another op amp. Too circuit specific.

 

AFAIK Felix uses the 5532 exclusively. He is the forum's authority on that particular op-amp.

OTOH my dac was originally outfitted with four 5532's, which I replaced with dual OPA 627's at $55 a piece. Never missed the 5532.

 

My experience indicates you are exactly correct. If you put an op-amp with incorrect input impedances or insufficient output current into a circuit it was not designed for you might hear something sketchy, but if you're operating within the manufacturer's specs in a suitable circuit design one should operate just like another. There was a musician working at one place where I did who was collecting any op-amps which caused our units to not meet noise or distortion specs and were replaced on the line - he had some grand scheme to try them in synthesizer circuits and make unreproducable sounds, but I don't know if he ever got anywhere. It was a very rare occurrence, anyway, far far less than 1% of devices dropped out in this way, and it would usually be an extra few dB of noise or hundredths of a percent THD which nobody was going to hear coming out of a speaker.

 

I switched out the 5532 and put in a National Semiconductor LM4562

 

Hello, old thread but I figured I would post. I just put a LM4562NA in my Asus Xonar DS sound card. The stock was a NE5532D. Before I get heat about this being placebo, I did quite a bit of A/B testing with this at home with the wife as a test subject. She picked them out 6 of 7 times, with the one time she was wrong being just the second or third test we did. Played some Sticky Fingers as it's her favorite Stones album.

While there wasn't any better thing per se, we both agreed it was less muddy and clearer.....more depth to things.

Anyone on the fence, spend the $5 and give it a whirl. Worth every penny!

 

Theres certainly no issue with re-engineering opamps in a given circuit considering the fantastic offerings from modern opamps. Yet you cannot escape the engineering word.. rolling without consideration of the circuit and the opamp is more likely to make things worse than improve them.

Case in point was my upgrading my QUAD 405/2. I searched the web high and lo looking for meaningful articles and the like before I changed anything at all. There were those recommended expensive OPA627s and the like but this didnt make sense to me. The QUAD 405 input stage is simply not designed for super quiet opamps equivalent to 25 Ohms resistance. The source and other impedances around the virtual earth totally dominate this stage and you have choose the right opamp carefully with the right 'Vn' AND 'In' values (for this circuit) if you want to achieve any benefit.

The only guys to provide quality analysis and work were BERNT and SNOOK and their recommendations were consistent with my calculations and I had decided that the "ideal" replacement for the QUAD 405 was the OPA134 - and I have to say I am mighty impressed with the result, silky smooth and you have to hold your head right up to the mid/tweets if you want to hear noise now.. And it was pretty noisy before with the factory TL071 installed.

Even with the correct noise calculations, the wrong opamp in the wrong location with the wrong power supply configuration may also be conditionally unstable with random HF oscillation or even clamping for starters? And we havent even talked about the load on the output yet..

I was very careful how I bypassed the + and - power rails for my mod and it paid off for me..

Rolling CAN work but you still have to do some homework and understand the package your working on if you want any chance of a positive result.

I know this is a prickly subject and these are only my opinions but I've been working professionally with opamps since the 1980s and I've had to rework many an unstable opamp board that has been incorrectly built because the designer didnt ask all the necessary questions.

I put together a quickie spreadsheet to easily compare typical new and old opamps (audio) and their relevant specs but I cant find a way to attach it to my post - maybe because Im still a noob here???