Parasound JC1's vs. Sim Audio W10

Zormi. I really wanted to like the JC-1's. The bass was definately better the second time round, but it had no life in the upper mids and top end. Just plain boring. I really think parasound need to change there caps as no one in their right mind can expect to wait 1200 hours for the amp to sound better.
The Mac 501's and Pass 350.5 sounded good after 50 hours, Krell 300cx was starting to sound better after 150 hours but still a little strident in the highs for my taste. cj after 120 hours, still improving. All these amps sounded at 95% plus at these hours, which is what high end hi fi should be like.

Interesting the low or no feedback designs ( prem 350, Pass 350.5, Sim W5) were to my ear the better sounding amps compared to their high feedback cousins like Parasound, Mac and Bryston. It was if the high feedback amps had a limiter on the expressiveness and natural tones in the upper mids/and treble. The high feedback amps had arguably the bigger bass thou. But it is top to bottom conherence and musicality that rule the day with my listening biases.

Downunder: I would not have expected the Pass amp to be a good match with your speakers. Most Pass amps are a little "round" sounding in the bass, albeit in a pleasant manner. The problem is that, when you combine it with speakers that lack damping, suffer from ringing and are round sounding to begin with, you've got WAY too much of a good thing. The Vienna's definitely fall into that category, at least in my opinion.

As to the high feedback amps sounding "closed in", this is what i predicted that the JC-1 would sound like after learning that it used gobs of negative feedback. While i was initially eager to hear this amp, after finding out more about the technical aspects of the design, i knew that i would not like it sonically. Somewhere in the archives, you'll find those comments, along with what i posted above. That is, high negative feedback designs tend to sound less liquid and sterile. They measure good on the bench, but simply don't sound "magical" or "musical".

As such, i don't doubt your results at all. In fact, a couple of them simply confirm previous observations that i've already made, all without hearing the gear or combo of gear in question.

There is one thing i'd like to add though. That is, you guys really need to check into using low impedance speaker cabling ( 20 ohms at MAX ) with amps of this calibre. The benefits with amps of "marginal" build quality are noticeable, but when you've got a real "powerhouse" of an amp using good quality parts, the benefits become even more apparent. That last level of "musical accuracy" i.e. "detailed notes that float in the air, dripping liquidity and impact" become a reality. That's because the amp can finally "load up" into the speakers and the power transfer characteristics are improved. Better power transfer characteristics means increased control, reduced reflections and improved sonics.

In my Dad's system, i changed his preamp, power amp, DAC, modified his speakers, changed interconnects, etc... When i finally installed some low impedance speaker cabling, he told me that those speaker cables made more of a difference than all of the other changes combined. What he didn't seem to take into account was that the change in speaker cables simply allowed him to hear all the benefits of the upgrades that had already taken place, which his other speaker cables simply didn't let through. After all, the cables aren't doing anything magic, they are simply reducing losses in the system.

By minimizing the losses, you get to hear more of what the system is truly capable of. So long as you have a good system, you should like what you hear. If you don't have a good system, you'll get to hear just how bad certain aspects of the reproduction really are. Don't blame it on the low impedance speaker cable though, because it's not an active part of the reproductive chain. It's simply a conduit for the signal that already existed. Now you get to hear the system, warts and all. Sean
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Sean, absolutely agree with you. The mahlers do have a rounded big bass. That was the biggest difference between the Pass X350.5 and cj prem 350. Bass was a lot tighter and more musical on the cj. Someone who owns a speaker with leaner sounding bass may prefer the Pass X350.5.

Re speaker cables. I used transparent ref XL, harmonic pro9 and borrowed some Kimber 3035 for most of the listening. All great insanely expensive cables. The transparent was clearly the least suited to my system sounding warm and bloated with little extension - this all relative compared to the harmonic and kimber.
The transparents can sound wonderful in say a Wilson or brightish sounding system. Any way I have sold them now to someone who will be able to appreciate them better than I.
I have Nordost Valhalla cables from TT to phono, phono to pre and pre to power. Most people think these sound lean or bright. yes they certainly have sounded like that to me as well. However in my current config they sound warm, transparent and focused, which pretty much matches the sound of my components.
If the valhalla's sound bright, it is one of your components that is making the brightness, not the cable.

anyway, happy listening

Downunder: Nordost's "design formula" for cabling can work well for interconnects, but it is simply electrically out of place for speaker cabling in a perfectly balanced system. This is not to say that their speaker cables are horrid, but that they definitely introduces specific sonic characteristics into a system due to the electrical characteristics that Nordost chose to work with.

Let's look at a circuit diagram of our system as a whole. Common sense should tell us that combining an amplifier with an output impedance of less than a tenth of an ohm ( most SS amps ) with a speaker that is roughly eight ohms and connecting the two with cabling that is well above 100 ohms would skew our electrical results. In raw figures, it would look like .1 ohm ( amp ) into 100+ ohms ( Nordost ) into 8 ohms ( speaker ). Obviously, there is an impedance bottle-neck which would create both a mismatch and a lack of proper loading / current flow characteristic. This is exactly what happens and the end result is a reduction in low frequency output, which is current driven.

That lack of current "chokes" the low frequency signal, which in a system that is already on the heavy sounding side, tends to balance things out. That balance is not achieved due to increased control ( exactly the opposite ), but due to a lack of signal being introduced into the speaker to excite that specific problem.

If the speaker is putting out too much bass, simply reducing the amount of signal fed into it helps to achieve a more linear output. This would be equivalent to turning down the low frequency controls on a preamp or equalizer. On the other hand, using an amp / cable with an "iron grip" wouldn't allow the system to over-compensate for a non-linearity in the output of a speaker. It would simply deliver the signal to the speaker which would excite it into the non-linear output of acoustic energy that it tends to naturally display. In effect, the only way that an amplifier could compensate for the non-linear output of a speaker would be if the amplifier itself was non-linear and / or using some type of active circuitry to monitor the output of the speaker itself i.e. "motional feedback".

With that in mind, i've always said that Nordost speaker cables would work well with speakers that lack proper damping in the low frequencies and / or are soft sounding on the top end. They tend to highlight a specific section of the audio spectrum, but do so at the expense of the opposite end of sound. This would explain why you're having such good system synergy with the Valhalla's, the CJ and your Vienna's i.e. both the amp and speaker cabling are somewhat lean sounding / lacking in low frequency capacity, which helps to balance out the abundant "warmth" in the speakers.

The end result is that the system sounds balanced, but in the long run, there really is a "scientific" & "mathematical" reason as to why it sounds as good and / or "tonally balanced" as it does. Had you been using different speakers, you're results would have most assuredly been different in terms of the cabling & amp that you thought sounded best. In your system with your specific componentry, i'm sure that the Nordost's don't sound lean. Then again, you're not just listening to the Nordost's, but to the entire system as a whole.

This is why i've tried to teach that one needs to pick their source, speakers and speaker cabling first, then look at the rest of the system from there. Speakers are the toughest choice, as they involve proper room loading conditions, specific placement considerations, various spl requirements, etc...

Maintaining a high level of electrical and sonic accuracy at both ends of the chain simply means that the components in the middle need to maintain that accuracy with the least amount of distortions. After that, the only other variable involved is how much power one needs in order to properly drive those specific speakers in that specific listening environment. Choosing speaker cabling that is electrically compatible with the speakers and loading characteristics of the amp simply allows one to hear more of what the amp and support components can deliver while minimizing one more variable in the equation.

This approach may not be as fun as the "trial & error" approach of buying and trying a million different speaker cables and / or components, but it is surely more consistent and far less costly. Whether one likes the "electrical accuracy" that such an approach brings with it is strictly a matter of personal preference and how good of a job they did in choosing the source and speakers. That takes into account that the other parts of the signal chain aren't extremely lossy or introducing their own distortions into the equation. Sean
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PS... It should be pointed out that the above comments are specifically discussing Nordost's speaker cabling and their electrical characteristics, not the entire line of Nordost products. As mentioned above, the electrical characteristics of their interconnects shouldn't present a problem / introduce gross electrical errors into most systems. That is, so long as the nominal impedance of the cable "somewhat agrees" with the nominal input and output impedances of the mating components. I'm not familiar with the design of their digital, video or power cords, so i can't comment on those.

As is usual, i'm simply sharing my point of view on the subjects being discussed. How much weight or validity one wants to assign to my comments is strictly up to them as an individual.

Sean,
What low impedance speaker cabling are you talking about?
I would like to know - any brands?
Thanks,
bill