OpAmps and specs vs preference

[Peter Galbavy]

Been staring at the Caiman mods and wanting to play opamp rolling I started looking at the various chips mentioned here in the forum and on Farnell's site via their search tool. It got me to wondering if anyone has taken a pseudo-scientific approach to tabulating opamps specs and somehow tried to rate their audio performance (which is subjective).

This is from the perspective of looking at slew rates, gain, freq, voltage ranges etc. to see if any patterns emerge.

If no one has, I might try to have a go.

[Peter Galbavy]

Just ordered these from Farnell, initially to meet the minimum £20 credit card order, but most were very cheap (£1-£2 each). Apart from the common ones already mentioned in the various threads I have no idea if the others are safe to use. I will read up, but comments welcome. I wonder what the Burr-Brown ones are like given that they have not been mentioned much here.

ANALOG DEVICES AD826ANZ
TEXAS INSTRUMENTS OPA2132PA
NATIONAL SEMICONDUCTOR LM6132BIN
BURR-BROWN OPA2228PA
BURR-BROWN OPA2244PA
BURR-BROWN OPA2137PA
ON SEMICONDUCTOR SA5532NG
TEXAS INSTRUMENTS LT1013CPG4
TEXAS INSTRUMENTS TL082IPG4

Will build a spreadsheet at some point soon.

[leo]

Should be fun and look forward to your results.

You've got quite a mixture there, not checked them all but some are fet input and others are bipolar , those types alone tend to sound quite different.
We won't bother going into all boring stuff, as long as their stable in the circuit it'll be interesting to see what you find
Things can measure the same but don't always sound the same

[sponge]

This is from the perspective of looking at slew rates, gain, freq, voltage ranges etc. to see if any patterns emerge.

If no one has, I might try to have a go.

As Leo says, you will have fun playing... But specs aren't everything - The humble NE5532 can sound very good and is well down the spec sheet. In my experience of opamp rolling the LM4562 (plastic or metal) will take a lot of beating - It was after all designed for audio, unlike some chips (eg. the THS4032) which are intended for video applications.

Just watch out for stability issues as Leo mentions - the THS4032 is particularly bad tempered and can cause some frustration.

I do like the AD826 and have stuck with it in my TC-7520 (with DAC upgrade) - Analog Devices chips do seem to have their own kind of sound - Quite unlike the Burr-Brown's.

In the end it's what YOUR ears prefer - Just have fun and give each chip a few minutes to warm up settle.

Ken

[Peter Galbavy]

I agree that specs are not everything but I am curious if there are any commonalities...

[sponge]

I agree that specs are not everything but I am curious if there are any commonalities...

Good luck on that - I'll look forward to your findings.

Ken

[Alex Nikitin]

NE5532 from TI is at the moment my favourite dual opamp in a purely analogue applications. I've found that it sounds more natural than LM4562 and the like. For a single opamp there is a better one - NE5534.

Alex

[Peter Galbavy]

Well, first package with 8 pairs of opamps turned up yesterday and I have a ship notice for the last pair also - I guess they were in a backroom box somewhere

I have printed out the datasheets for material to digest and will slowly put together a table of specs. In terms of the electronics side I am a neophyte, so time to read up on everything from scratch again (last time was maybe 25 years ago).

I hope I get time to play this weekend but with a friends BBQ on the casrd this may be difficult.

[Peter Galbavy]

While attempting to study the basics I came across this book online:

http://www.analog.com/library/analog..._handbook.html

It's the PDFs by chapter of Analog Devices publication described as: "Op Amp Applications Handbook, edited by Walt Jung (Newnes, 2006), comprises Op Amp Basics, Specialty Amplifiers, Using Op Amps with Data Converters, Sensor Signal Conditioning, Analog Filters, Signal Amplifiers, Hardware and Housekeeping Techniques, and Op Amp History. As the name implies, it covers the application of op amps, but does so on a broader scope. It also covers a host of closely related design topics, making it a formidable toolkit for the analog designer."

Chapter 1 - so far - is very readable and the chapter on op amp history is also very good and appears to be where all the pics and text on the Wikipedia article comes from.

[Codifus]

I agree that specs are not everything but I am curious if there are any commonalities...

The OPA2132 got alot of play on quite a few 7520s here. By the way, the TI OPA2132 *IS* the Burr Brown OPA2132. TI and Burr Brown merged (or TI bought Burr Brown) in 2000.


When i had OPA2132 in my setup, i found it to be laid back with musical timing, really really good with vocals, seducively so even, and a slightly monophonic soundstage, compared to the LM4562. I came away with the impression that the OPA2132 was the one for voice, but the LM4562 was better with instruments. The OP2132 was a very relaxing chip

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