Zu Audio speakers and accessories

I'm missing the lower octave with my Tektons and my accord sport will never return it's claimed 35 mpg. But it doesn't stop my enjoyment of either.
 
Right on. I have no problem with people enjoying whatever it is they like. I have an issue with lying, though. Tekton, from what I have seen measures within a reasonable range of reality. Zu takes the peak and the frequency output, uses that as their bassline sensitivity, and then arbitrarily picks a low frequency range that is sometimes an octave or two below reality.
 
Car companies lie on real life mpg's but it's not much of an issue. How is that different from speaker companies exaggerating specs?
 
Car companies lie on real life mpg's but it's not much of an issue. How is that different from speaker companies exaggerating specs?

The car analogy doesn't apply here. Observed MPG is directly related to driving habits. Somebody hot on the throttle will get worse MPG, and somebody that is easier will get better MPG. For example, according to the EPA, my Chevy Venture gets 19/25, but I'm observing 21/29. On a speaker, there is consistency between the driver and cabinet, therefore, all should measure the same in the same room, exaggerated or not.
 
PG, I don't think the analogy is all that applicable. First, there are standards for determine mpg and all the players follow them regardless of the idealism represented by the numbers. In the speaker industry, -3db is used to represent the upper and lower bandwidth. Sometimes you'll see variations on it, but not too often.

What Zu is doing is saying ignore the 22/30 city/highway fuel economy that was tested, our cars get 45mpg.
 
Actually, it's a little less subtle than that... the US federal government mandates the test standards for MPG (and, still, for domestic stereo receiver and amplifier power output) -- but, at least in the US, there are no government-mandated standards for loudspeaker bandwidth, so it's still the Wild West on that front. No laws broken by Zu, irrespective of one's assessment of their honesty (edit: oh, and not that I disagree, by the way -- I find them to be rather unpleasant to listen to, which probably corroborates the measured frequency response).

... like the Wild West days of output power claims in the US :)

LRE LA-975 by mhardy6647, on Flickr

Indeed, all specifications are meaningless in the absence of either widely-recognized standards (of which, I'll give you, the "-3 dB point" is) or clearly stated criteria for the conditions used to assess performance against the specification.
 
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Back in my car audio days, Infinity got a bad rap for posting their sensitivity ratings in car. While JL Audio, Kicker, and others were hovering in the 85db range, infinity was regularly in the mid 90s. I never had an issue with it as they always specified their test conditions as part of the spec.

I can totally understand why Zu wouldn't want to publish a 200-20khz bandwidth, but if the advertised a 70hz or so f10, I'd have no issue.
 
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To note - the UK often uses -6db as their point of reference not -3dB as audibly -6db is usuable. Paradigm in Canada uses -10dB as usable.

Standards are typically standards because it's easier to do and not for much else. Stereophile (and worse Harman International) has a set of measurements that don't make much usable sense if the speaker is in any way not the norm - like panels, omni-directionals, or corner loaded designs - the results they get are virtually completely worthless for these kinds of speakers.

There is bass - great - the number of speakers that claim 40hz in the small standmount market is dizzying. My Wharfedale Vanguards also claim 40hz - big floorstanders - It was laughable to hear a Paradigm Studio 40 monitor claim 40hz against my Wharfedales. Umm someone forgot to mention volume level - The Wharfedales could and will blow you into next week hitting its bass at high levels and not compressing and crushing the room. The Paradigm sounded lifeless compressed and banal trying to play the same kind of bass. Although the speaker did other things like soundstaging better.

Single Driver speaker makers probably try and put their speakers in the best light but in reality the listening will bear it out. I've heard the bigger ZU speakers here in HK and the sensitivity and bass are ample enough. Though I am not convinced by the actual sound quality of the speakers because it sounds thin and largely washed out.

Remember many speaker makers are measuring both speakers and putting the combined measurement together which yields higher sensitivity and in room results reveal better bass numbers. An anechoic or quasi anechoic measurement usually only measures one loudspeaker in the middle of a room lowering the sensitivity and of course removes room gain.

With my own AN E - Art Dudley measured them as being flat at 25hz in his room at his chair - The same magazine measured them in their quasi-anechoic condition and didn't get that kind of bass nor the sensitivity rating one would expect from a company selling 8 watt amps. Across the pond in England Martin Colloms (who was the technical editor for Stereophile for years) however measured them as hitting 18hz -6db AND 94.5dB sensitive. Hi Fi Choice mustered 22hz-3dB on the lower J model not in corners.

But Poultrygeist hits the nail on the head. The worry of a particular set of numbers and real world use has to be in play. The manufacturer isn't lying if what he got in his testing room is different than what Stereophile got in their garage. Contrary to popular belief - many makers laugh at the testing equipment that Stereophile uses as being hopelessly insensitive and out of date. Not to mention that the results bare little in common with what the reviewers actually hear and/or buy.

Go put on whatever bass heavy music you like and ask yourself if you are getting enough bass.
 
Wouldn't buy a car based on numbers and didn't buy the Zu's based on numbers.

If we were slaves to truth in advertising we'd own very little.
 
That's simply not true. A gigantic majority of the high end audio industry reports things in a similar way and I've really never had a cause to not believe most of them. It's relatively rare to find anyone really stretching the truth, significantly. Klipsch likes to play games a bit, but even they aren't massive offenders. I've honestly never come across an audio company with more outrageous claims than Zu, outside of some of the walmart HTIB systems claiming 1500w or similar. I just don't understand the rationalization of deceitful practices. If numbers don't mean anything, they certainly aren't going to stop selling speakers, so why not come close to the truth? I think the lies prove beyond any reasonable doubt that specs mean something to consumer and to Zu.
 
I don't understand it either -- it was much more common (in speakers) in the 1950s and 1960s; indeed in those days, the term "frequency range" (although not typically defined) was widely used and could generally be understood to cover the -10 dB points.

As to the truth or lack of same; the fact is that, in the absence of "the rule of law", any standards (ISO, EIA, NAB, DIN, etc.) are de facto standards. That doesn't mean that they are NOT widely acknowledged and adhered to, but only corporate integrity will provide any guarantee of compliance (although, e.g., the ISO 900x standards do include a 'third party' review component). "Corporate integrity" isn't quite an oxymoron... but it can be!

My vocation was in the context of a regulated industry (so-called ethical pharmaceuticals); non-compliance could, and did, lead to loss of licenses, fines, and even imprisonment.

Now, if Zu is a public company and if they play as fast and loose with their earnings reports as with their FR... that's a legal matter, baby. ;-)

As it is, Zu risks "only" their reputation and consequently the magnitude of their business. My guess is that they figure that enough people will listen and buy based on their taste rather than any hard numbers (accurate or fantastic) to obviate the importance of their honesty. Whether they're right or wrong; only time will tell. Unfortunately, there's an 'anti-science' movement in the "developed" world today that makes some folks quite skeptical of the old status quo of objectively-determined "factual data". The fringe audiophile market is chock-a-block with that kind of "anti-rational" thinking; companies like Zu play to that audience, I'd opine.

Please note that we are actually in agreement, if violently, as to the execrable nature of Zu's performance claims, but they can always claim something akin to this: the 'currently accepted' standards are flawed, We used proprietary methodology to assess real-world performance and our specifications reflect our ground-breaking research. No third party can reproduce our results because they do not have the sophisticated [model, software, hardware, etc.] to perform the appropriate tests."

I.e., the "100 mile per gallon carburetor" (or Nikolai Tesla) approach to "truth"! :)
 
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SET amps measure so poorly. Inefficient, low output, poor damping factors, high levels of harmonic distortion yet owners would have nothing else.
 
But again, you don't see SET amp mfgs claiming otherwise (that I've seen). If they were claiming DF of 200, low end frequency response of 1hz, and THD of .01%, I'd not hesitate to call BS. I feel like we are talking two different languages, here.
 
SET amps measure so poorly. Inefficient, low output, poor damping factors, high levels of harmonic distortion yet owners would have nothing else.

True, for some people, personal experience trumps specs, and with SET, that was the case for me.

The thing is though, I heard Zus on several occasions and decided quite definitively that I didn't like them - very poor bass, lack of dynamics, a kind of hollow coloration and they seemed extremely strained with 45 and 2A3 SETs.

I saw the measurements after direct experience and aside from the weird mid-range coloration I didn't care for, proper specs (showing limited bass, not highly efficient) would not have had me thinking they are something they aren't. I went looking for a full-range low power SET friendly speaker and their 'published' specs led me to believe they were a contender - they weren't even close for me.

After getting jaded by 'measurements & specs' with the SET experience, Zu taught me to respect measurements again. Yes, listening is what truly matters to me and will always win in the end but with the Zus, real measurements and specs might have kept me out of the 'hate them' camp and simply left them off my radar as not a candidate for my system.
 
But again, you don't see SET amp mfgs claiming otherwise (that I've seen). If they were claiming DF of 200, low end frequency response of 1hz, and THD of .01%, I'd not hesitate to call BS. I feel like we are talking two different languages, here.

My point is that I don't put much stock in specs or claims, real or imaginary.
 
But again, you don't see SET amp mfgs claiming otherwise (that I've seen). If they were claiming DF of 200, low end frequency response of 1hz, and THD of .01%, I'd not hesitate to call BS. I feel like we are talking two different languages, here.

OK, you made your point. You can get off your soap box. How many times to you need to rant on this subject?

If you do not like Zu speakers, do not buy them. There are plenty of other speaker manufacturers out there.

I personally, do buy based on specs alone. They do offer a 60 day satisfaction in home guarantee, by the way.
 
OK, you made your point. You can get off your soap box. How many times to you need to rant on this subject?

If you do not like Zu speakers, do not buy them. There are plenty of other speaker manufacturers out there.

I personally, do buy based on specs alone. They do offer a 60 day satisfaction in home guarantee, by the way.

This is a discussion forum and if people reply and pose analogies, questions, etc, I'm very likely to reply. I'm sorry if discussion makes you uncomfortable.
 
This is a discussion forum and if people reply and pose analogies, questions, etc, I'm very likely to reply. I'm sorry if discussion makes you uncomfortable.

Yeah, that subtlety seems to get lost sometimes, especially recently :-(

Funny thing about asking for opinions -- some folks' opinions will be different than others.

Oh, speaking of SETs and... shall we say... misleading specifications (or claims). Steve Deckert (Decware) originally claimed, in print, that his SE-84 "Zen" SE EL84 stereo amp was a five watt per channel amplifier. It was not (it's pretty much impossible to get 5 watts continuous, broadband from an EL84, or the SV83 tube he touted for it, in triode mode)... and Deckert eventually did capitulate -- although he never quite admitted that he had said or done anything 'wrong'.
http://www.decware.com/zpower.htm

EDIT: Just to be clear, the issue here isn't with the performance of the Zu products (or Deckert's amps) per se, it is with claims about performance that don't withstand scrutiny. The former is strictly a case of caveat emptor; the latter is at least misleading, most likely (as Dave has pointed out) a poor business and ethical practice and (as I attempted to say) under some circumstances perhaps even a violation of law.
 
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Some of you might be surprised how many drivers don't measure up to their advertised specs. Can't say those companies are thrown under the bus over at DIYaudio or the PE forum.
 
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