Carver Pro ZR1600

El: Op amps have the potential for high quality sound, but most Op amps are under-designed mass produced pieces of junk. They work great for many applications, but many of them just aren't suitable for use with "hi-fi". On top of that, when put into a circuit that is an under-designed piece of junk, you end up with one BIG under-designed piece of junk.

If you would like further clarification as to why many Op-amps are "junky", try reading a very informative article written by Ben Duncan as published in Stereophile a few years back. This amassess the results obtained after testing over a dozen different Op-amps from various manufacturers. Some of the same Op-amps from different manufacturers performed VERY differently. We are talking about S/N ratios that varied by as much as 40 - 60 dB's here. Needless to say, a few dB's here and there might be understandable, but not variances as mentioned above.

As a side note, this article also mentions thermal distortions, which most IC's are not very good with. Sean
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sean...Yes, noise is a significant characteristic of an Op amp. However, the OP Amp circuit topography is such that an IC which is "junky" in other ways, like distortion (thermal or otherewise) gain tolerance, slew rate tolerance (as long as it is above some value) etc, will work just as well as an OP Amp that is perfect in these regards. Op amps can only be evaluated in context of the performance of the overall circuit in which they are used. They should never be thought of as a linear amp.

Eldartford,

Carver pro's hands are tied. They can only sell to the pro market. All this Audiophile stuff took them by suprise. Do to legal reasons they can not market to the home user BUT you can buy a pro amp for your home system if you want to!!!

You will see different products to go with the ZR seris also. I don't think that Carver Pro will be doing the mods themselves, but as you can see,are letting some of the best people in the business do the mods and sell them.

Hope this helps,

Larry

El: You stated that Op-amps "should never be thought of as a linear amp".

If these are your honest thoughts on the subject, why would you buy a unit that uses Op-amps for hi-fi use ? After all, "hi-fi" is all about "high fidelity" i.e. linear replication of a signal. Are you now saying that the amp that you are happy with / raving about is a non-linear device, but you like it anyhow ? Help me to understand where you are coming from with these statements as they seem to be contrary to your previous posts in other threads. Sean
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lkosova@yahoo.com...Trust the lawyers to screw things up!

sean...The circuit, which includes the OP Amp is linear, even if the open loop performance of the device is "junky".

An analogy might be the output transformer of a tube amp, where, when tested as a component, out of its circuit, its bandwidth and frequency response is "junky". However, put it in a circuit with appropriate feedback (usually derived from extra windings on the transformer) and the resulting performance can be superb.

Certainly there are different levels of OP amp quality, Noise being the parameter of greatest interest. Also, the type of circuit that the device implements affects the degree to which the "junky" characteristics are suppressed by the circuit. For a unity gain buffer amp, (which is what the OP Amps in the Carver ZR1600 mostly are) quality OP Amps would be of minimal value. (Resistors and Capacitors should be the principal concern). When you try to implement a phono preamp, with high gain and heavy RIAA equalization, it's a different story. Even the "best" Op Amps are not so hot in this application, which has given Op Amps their bad reputation.

I guess this is another case of a myth (Op Amps are always evil) that is based on a kernel of truth.