Carver Pro ZR1600

Glad you like your amps El. I hope that they do everything that you wanted / expected and even a bit more : )

For sake of clarity, these amps are not made by the Carver Corporation or have anything to do with Bob Carver. I made that mistake myself and someone on Audiocircle clarified it for me. Phoenix Gold purchased the rights to use the name Carver Pro several years ago and are marketing various cables and electronics using that moniker. Sean
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El: I don't doubt your observation comparing the ZR1600 to the Adcom. Adcom amps to me have always tended to get muddy, blurred and jumble things up at volume. This also includes the big ones that Nelson Pass designed and Adcom built to their own spec.

As far as your comments about bypassing the switches, you need twice the amount of contacts on a switch in order to reduce audibility of a decent switch. In other words, two contacts in and two contacts out wired in parallel reduce the audibility of a single switch in the signal path. As such, where one is using a single pole double throw ( spdt ) switch, going to a double pole double throw ( dpdt ) would work better. The only thing with this is that you end up with a whole lot more making and breaking of the signal path and solder joints galore. If you have no fear of overdriving the amp, i would suggest using good quality cabling and bypassing all of that. On top of that, don't forget to break the connections feeding into the circuit at the board level. Having circuitry that is still connected at various points but not active will cause differences in signal loading. Sean
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El: Try using solder as an interconnect rather than a speaker cable. The gauge of the solder used would be more appropriate for line level signals than for the much higher current levels of a speaker connection.

If i remember correctly, i think that Jennifer Crock of JennaLabs did this with several different solders. According to audiophile folk-lore, she preferred Cardas solder to the others that she tried in this manner.

As a side note, take a relatively long yet identical length of various generic and high quality solders and measure the resistance of them using precision test equipment. My business partner kept telling me that "solder is solder", so we did this along with some other tests at the shop using some of my HP test equipment. Needles to say, he was pretty amazed at the differences in conductivity between various solders. Then when i explained to him the differences in metallurgy in various solders, the variances in how different solders dry, bond to the surface and how well they hold up over time, he wanted to verify this. After watching how various eutectic and non-eutectic solders performed in these areas, he was pretty much a "convert" as far as "high tech" solder goes. Sean
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I have a question for you guys that are familiar with these Tri-Path amps. I have heard two of these amps, but not under conditions that i was familiar with or could really pass judgment with. Compared to a modified Adcom amp, i thought that the Tri-Path's were a step forward.

How do these amps do with lower impedances ? From what i've seen, they are higher in distortion at 8 ohms and measurably lacking in terms of the ability to pass current as impedance drops. On top of that, if they are like most other amps, the distortion will climb noticeably as impedance is reduced.

Given that i tend to prefer speakers that have a lower impedance with high quantities of reflected EMF ( multiple drivers, large motor structures, speakers with sharp phase angles like E-stat's ), i have to wonder how suitable they would be for installations using anything but benign dynamic loads ?

In my book, a "good" amp should be able to drive most any load that you throw at it. Obviously, some will do better than others due to build quality and circuit design, but then again, some do miserably with all but a few types of speakers. As such, what i'm asking is "how universal are these amps" and "do you think that the results that you are obtaining in your system will be easy to duplicate in other systems" ? Sean
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El: I've got over 1400 wpc rms driving some 86 dB 4 ohm speakers. I don't know how your maggies would respond, but i know that this is how i was finally able to get my speakers to sing. I know that Mike aka Magnetar over on AA was using Classe' M700 mono-blocks ( 700 @ 8, 1400 @ 4 / 3 dB's of dynamic headroom ) to drive his Maggie 3.5's, which were slightly older but more expensive models. From what i can gather based on the path that he took after this, i don't think that he found this to be "dynamic" enough for him. As such, you better order another amp or two : ) Sean
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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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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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