I have no experience with the Lightstar II. I've been told that the Lightstar amps "might" be slightly more transparent sounding than the Sunfire's but with very similar circuitry. This was told to me by an employee of Sunfire.
As far as your comments about your friend the EE and amp designer, all i can say is that he either needs better test equipment or to run some different tests. Prior to improving the tools that i had to work with, i was not able to measure differences in equipment once a certain threshold was achieved. Even though the equipment that i was previously using was nowhere near "state of the art", i was still able to measure and discern differences in performance above the aforementioned threshold ( which was actually quite low ) with good accuracy. Going to better test equipment simply gave me better resolution. This enabled me to measure and discern the differences in performance between components to an even greater extent. Granted, the increased resolution of the newer test equipment set me back a good chunk of money, but it also opened my eyes / ears / mind to the fact that i was not able to see / measure everything as well as i thought i was previous to the upgrade.
When all is said and done, i guess that we will just have to agree to disagree. Sean
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PS... If some of you are under the impression that all audio designers, manufacturers, designers have a full assortment of high quality test equipment at their disposal, guess again. I've seen some of the "test benches" and "design labs" that various "manufacturers" use. Some of the gear that these "techs" and "engineers" are using to design and test their products is equipment that can be found at flea markets. This is NOT to say that the gentleman that Paulwp is referring to is in this boat, but given the point of view being expressed here, it "might" not be far off.
PPS... If gear wasn't changing in a measurable manner as we used it, it would never break down. Parts are shifting and decaying and that is why circuits fail or go out of tolerance. Whether or not you want to call this "break-in" or "settling" is a matter of semantics. Sean
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Sean...The design/production philosophy formalized by Taguchi is in general use throughout industry, with the exception of some very small outfits where doing it the old way is a tradition, and this may include most high end audio firms. Good performance can be achieved on a unit-by-unit basis doing things the old way. The consequence of not using the Taguchi approach is high cost, and unreliablity, and that fits high end audio pretty well.
The first example usually cited regarding Taguchi method effectiveness is the camera business in Japan. After WW2 Germany was famous as the maker of the most superb lenses and cameras. They had skilled workers who could grind lenses better than anyone else, and they kept their trade secrets to themselves. Japan realized that they could never match the skill of these workers, and so could not produce cameras comparable to the German product. So, using the Taguchi approach, they figured out which pieces of glass in the lens system were hard to make right, and they designed new lens systems that did not rely on exceptional precision of any of the elements. As a result of this effort Japan became dominant in the camera business.
Example 2 is the superiority of Sony TV sets, vs RCA, GE, Sylvania, etc. I don't think the USA manufactures any TV sets anymore. |
I could be wrong ,but, I think some Sony TV's are made in the U.S.A..
Some business practices commonly associated with Japan are actually the result of American minds.
I think that Sean is right about break in. Loudspeakers often sound quite awfull out of the box, then settle in to produce the sound we expect for some time. To borrow an expression/analogy from finance, it is much like the bathtub effect. Initially products may often demonstrates a wide vacillitaing quality, then settles in to perform with more consistentcy for much of its life, and then due to age,wear,etc., starts to demonstrate varying quality (though not necessarily identical to the break in period) till it fails. |
Eldar, you're right about the role of Taguchi approach in industry in general, but what should be taken into consideration, is that markets for Sony TVs and hi-end audio are quite different, and so different their consumer's demands. Unlike Best Buy clientele, hi-end audio consumer is interested in "in a margin representing the last few percents of what's attainable", as was mentioned in another thread. For any hobby of this kind (audiophilia, wines, cars, etc) all the joy and satisfaction is expected from those few percents, and not about the rest 97% of normal, mass-oriented, healthy and practical minivan-styled stuff. One of the reasons that cause one to purchase a unit for several thousands dollars is a fact (or at least idea from advertising of that product) that its manufactured with hand-made approach, sometimes manually tuned shortly, resulting high price is actually a positive factor here - just opposite to Taguchi direction. |
Unsound...We all agree that loudspeakers (and phono pickups) improve with use as the elastomers soften up.
As I mentioned, Taguchi was a disciple of W Edwards Deming, whose genius was not recognized here.
Dmitrydr...If there is a "high end" TV, it's Sony. You pay more for a Sony, and it performs better. But, they don't tweek each unit to make this happen. They tweek the design and the productiuon process so that EVERY unit that comes off the line is superior.
Everyone...How is the weather out your way? |
Eldartford, I meant a difference between even very good mass-market product and hi-end. Among TVs I would think about Pioneer in this group, but not Sony. It's not just a matter of "better quality-higher price", it's matter of different markets: I guess under normal circumstances you don't come to Best Buy for your next amp upgrade? If you build a graph Price=F(Quality) on some stage it will go up much faster then before, i.e. a little increment in quality will cost much more money then similar increments before. Here comes audiohile's market. If you don't tweek the product, it'll be declined: as per the same graph, for normal practical approach it's worth to go a little bit down in quality for quite significant difference in price. |
I guess it is clear that there is no need for another EE like me to comment on this, however I am about to. The thread has drifted to where it is hard to tell what the latest consensus is but if it matters at all, I think we tend to over-analyze burn-in a lot. I have done lots of research in system reliability (for aircraft systems mostly - they get picky about this sort of thing) and capacitors are by far the biggest problem and change the most. However, I hate to say it but the design uses a given value and not every component is matched when installed in your amp (and it drifts anyway), thereby making burn-in moot for amps and preamps. However, speakers are a different story...but that is for another thread.
As a final note, we don't actually understand everything in the universe, do we?? Some of you sound like you do. Each year I spend in EE courses (I am now at year 8), I realize how little we actually understand well - and that is the part that shouldn't be forgotten. Everything changes, nothing stays put. Arthur |
Aball, back to an earlier question: when you say that capacitors drift, for a given type of capacitor, do they always drift in the same direction? |
Aball: "However, I hate to say it but the design uses a given value and not every component is matched when installed in your amp (and it drifts anyway), thereby making burn-in moot for amps and preamps."
If i sum up your statement here, it reads as the following to me: "Components are typically not precision matched upon installation and will shift in value over time. Due to the shifting values, measured performance and possibly sonics may vary from the time that you first start using a brand new product till the time that it breaks down and needs repair". Does that sound about right ? If you are in agreement with that "interpretation" of what you said, would you say that most electronic components typically reach a plateau and stabilize in value for a period of time before reaching a point where decay starts to set in ?
Other than that, I agree with two of other points that you made that aren't really open to interpretation. The first one is that caps typically show the widest variance in measured value over time. I will also add that they typically display one of the highest, if the not THE highest, failure rates of any given component. The second point was "the more you know, the more you realize you don't know". I think that this saying is pretty self explanatory. Sean
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