I don't claim to know enough about electronic circuit design to speak to the characteristics of a given op amp. For that matter, I don't know enough about circuit design to speak to many of the issues involved in using or not using op amps in the first place, except to say that you need something - and if it's not op amps, it's going to be discrete circuits that are going to add some (potentially appreciable) cost. It does seem worth pointing out the drastic scarcity of processors, receivers, or source components that don't use op amps. As already mentioned, the stock DVD-3930CI (with a list price of $1500) uses them. The Anthem AVM family of surround processors (AVM20 through AVM50) and Anthem Statement processors (D1 and D2) use them. The Lexicon MC-12 uses them. (For what it's worth and in light of some of the earlier discussion here, I also thought it was interesting to note that both Anthem and Lexicon are using Burr Brown op amps - specifically either the OPA 2132 or 2134.)

A bit of googling did turn up at least one home theater component that was designed to use discrete circuits instead of op amps: Lexicon's RT-10 universal disc player. Of course, the RT-10 also had a list price of $3500 and faired poorly in Secrets\' video benchmarks . It's successor the RT-20, with a list price of $5000, retained this audio design but improved on the video performance. I have no doubt that other op amp-free designs are out there, but if the price tags resemble the RT-10 and RT-20 I'm not going to lose much sleep over them.

http://www.sacdmods.com/index.html

FYi, this is now his reference machine, the Denon 3930Ci!

Lizard King,

Thanks for the link.

you are welcome. Should you contact him, mention Paul referred you.

rob b, let us know what you think when you change the op amps out.

Usually people who say things like "op amps don't belong in analog circuits" fall into one or both the following categories:

1) People trying to sell something
2) People who are unqualified technically to make such statements.

At least it's not as obvious as folks selling $1000 wire.