Real Men Don't Use Opamps

[caesar148]

Op-amp has never been considered as an option for building true reference quality amplifiers. Discrete parts seems to be the way to go. You only use opamp for "cheap" amplifiers destined for the masses.

Am I mistaken or is there some truth in this?

Now we have a descrete opamp from Burson Audio of Australia and is sold by Parts Connexion.

http://www.partsconnexion.com/Index/burson.php
http://www.bursonaudio.com/

Their reason for designing a discrete opamp is to address the problems we have been trying to avoid.

[leadbelly]

Have you read any of the Blowtorch preamp thread? This was discussed ad nauseam fairly recently.

[Bob Cordell]

Originally posted by caesar148
Op-amp has never been considered as an option for building true reference quality amplifiers. Discrete parts seems to be the way to go. You only use opamp for "cheap" amplifiers destined for the masses.

Am I mistaken or is there some truth in this?

Now we have a descrete opamp from Burson Audio of Australia and is sold by Parts Connexion.

http://www.partsconnexion.com/Index/burson.php
http://www.bursonaudio.com/

Their reason for designing a discrete opamp is to address the problems we have been trying to avoid.

This reminds me of a book I bought a long time ago. It's title was "Real Men Use DOS".

Care must always be taken with the inevitable advance of technology when making generalizations. While it might be true that the very very best preamps are made with no op amps in the signal path, it is probably just as true that many very good preamps made with very good op amps are superior to many preamps made discretely. The only safe generalization is that generalizations are dangerous.

Cheers,
Bob

[analog_sa]

The Burson thingie looks quite ridiculous. Won't even comment on the price as it looks like it would cost ten bucks max to clone.

Has anyone actually heard it?

[Onvinyl]

Hi,
this is a DIY site, so how about posting the schematic (in case you have it, of course). It's really pointless to debate your point without some hard facts.

Regards,
Rüdiger

[Peter Daniel]

Originally posted by analog_sa
Has anyone actually heard it?

Nuuk did: http://www.tnt-audio.com/accessories/hdams_e.html

[analog_sa]

Thanks PD. Have read this before but completely forgotten. Nice review. Pretty much what i would have expected from a discrete opamp comparison especially taking into account that none of the tested opamps sound even remotely good IMO. The buffer review is more mystifying: no down side at all?

[sparcnut]

I think that a system should be judged by how it performs. Simply having opamps in a circuit certainly should not mean that it is bad or will sound bad. Real men don't judge a circuit by its components; they judge it by its sound, using measurements as a tool to help quantify how good it sounds and as an indispensable aid during design and construction. This is of course just my opinion, so you don't have to agree.

Now, as for the Burson opamps... without performance measurements, you cannot truly judge how they perform (or even what they do!).

[leadbelly]

Originally posted by sparcnut
Now, as for the Burson opamps... without performance measurements, you cannot truly judge how they perform (or even what they do!).

And exactly which measurement or test are you referring to?

[sparcnut]

Originally posted by leadbelly
And exactly which measurement or test are you referring to?

Everything - at the very least (in no particular order):
- input noise vs. frequency
- psrr vs. frequency
- cmrr vs. frequency
- closed-loop distortion with varying gain (inverting and non-inverting), loading, output voltage, and frequency (as spectral output, not single THD value) <--- probably the most important
- slew rate (just out of curiosity)
- unity-gain bandwidth
- phase margin / amount of ringing with varying capacitive load

Also would be nice:
- (very difficult/impossible on a real circuit) open-loop gain vs. frequency
- effect of source impedance on closed-loop distortion

And finally, complete telltale (although Burson wouldn't be happy about its publication):
- reverse engineered schematic