I second Bombaywalla's excellent comments, which I saw as I was just about to post the following:
As someone with significant experience designing op amp-based circuits (although not for audio applications), I am highly skeptical.
I would ask him what the manufacturer's part numbers are for the existing and the proposed replacement op amps. Post back with that information and I or someone else can look at the manufacturer's datasheets and hopefully develop a better idea of what the differences might be.
Also, ask him what other equipment he has tested this exact substitution on, and if that other equipment includes any electronic crossovers.
Some additional thoughts:
1)Substitution of a faster device, or a device that may be "improved" in other ways, in a proven op amp circuit design by no means guarantees improved performance. It amounts to a circuit redesign, which if not designed and tested carefully could just as easily degrade performance.
2)Op amp circuits are typically designed so that their performance is as independent as possible of variations in the parameters of the particular op amp, within the range of variation that can be expected for the particular device that is used. In other words, circuit performance is designed to be primarily dependent on the passive components that surround the op amps. Seconding 4est's suggestion about capacitors, I would expect that upgrading the 15 to 20 year old capacitors that are used to implement the crossover slopes would be more likely to make a meaningful improvement, with far less risk of adverse effects.
3)As far as I am aware technological advances in the last 15 to 20 years, that would be applicable to op amps used in audio applications, have been minor at best.
Regards,
-- Al
As someone with significant experience designing op amp-based circuits (although not for audio applications), I am highly skeptical.
I would ask him what the manufacturer's part numbers are for the existing and the proposed replacement op amps. Post back with that information and I or someone else can look at the manufacturer's datasheets and hopefully develop a better idea of what the differences might be.
Also, ask him what other equipment he has tested this exact substitution on, and if that other equipment includes any electronic crossovers.
Some additional thoughts:
1)Substitution of a faster device, or a device that may be "improved" in other ways, in a proven op amp circuit design by no means guarantees improved performance. It amounts to a circuit redesign, which if not designed and tested carefully could just as easily degrade performance.
2)Op amp circuits are typically designed so that their performance is as independent as possible of variations in the parameters of the particular op amp, within the range of variation that can be expected for the particular device that is used. In other words, circuit performance is designed to be primarily dependent on the passive components that surround the op amps. Seconding 4est's suggestion about capacitors, I would expect that upgrading the 15 to 20 year old capacitors that are used to implement the crossover slopes would be more likely to make a meaningful improvement, with far less risk of adverse effects.
3)As far as I am aware technological advances in the last 15 to 20 years, that would be applicable to op amps used in audio applications, have been minor at best.
Regards,
-- Al