Archive for November, 2009

Tekton Design – URUZ Measurements Published!!

Posted in Uncategorized on November 24, 2009 by tektondesign

I’m very proud of the level of engineering execution we’ve achieved regarding the Uruz loudspeaker. The Uruz model truly raises the bar to a new level of performance in the high sensitivity direct radiator loudspeaker category.

And now that the new Zu Essence measurement data is in the public domain (view it online — October 2009 Stereophile review), I’ve chosen to go public with Uruz performance data. After all, both loudspeakers are geared towards an identical audience. Both systems use nearly identical 10” drivers (though I choose not to implement the phase plug modification), and they both use ribbons.

Here’s what the URUZ promises to deliver:

  • Superior frequency response linearity +/-3dB (competitors design is +/-10dB variance)
  • Improved impedance linearity
  • Superior phase response
  • A true 8 Ohm system – with a Z-minimum of 6.16 Ohm
  • Superior impulse response & step response
  • A near identical sensitivity SPL performance rating
  • Only 2 components in the audio signal path!!

Best regards,

Eric Alexander

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Tekton Design Custom Audio…

Posted in Uncategorized on November 21, 2009 by tektondesign

Do not forget that we are the “Monster Garage” of audio. No custom project is too big or too small!

Open Baffle Loudspeakers – DIY

Posted in Uncategorized on November 18, 2009 by tektondesign

We do have single use “do-it-yourself” licenses available for the patent pending – award-winning open baffle hybrid loudspeaker. The price is $50 (US Dollars).

Please inquire…

Rear Firing Vents…

Posted in Uncategorized on November 13, 2009 by tektondesign

So, why do I place the vents on the front of the cabinet when a number of my competitors locate it on the rear?

Answer: You will perceive a stronger and more defined bass output with the vent on the front of the cabinet – period. You will realize a better impulse response and proper sense of timing when the vent is located on the front of the baffle – period. If you’re reading something or if someone is telling you differently, run! Vent placement is very rudimentary acoustical physics. In full-range design (with its inherent bass-producing limitations; for example, small driver surface area, very low moving mass, etc.), squeezing the maximum amount of extended bass out of the system is a specific design goal.

Having the vent radiate from the same plane as the transducer is classic Helmholtz resonator acoustics. Have you ever seen opening slits on the rear side of a guitar or violin? No one in their right mind would ever put them there. The resonating slits are right there, directly below or directly adjacent the strings – which is exactly where they should be. Loudspeakers are a bit more forgiving (typically tuned and operating at much lower frequencies than guitars and violins, so rear vents are actually quite common).

Rear vents came onto the scene when some guy realized that he didn’t have room for the vent on the front baffle of his loudspeaker. Sorry if this rains on your parade, but it’s the plain and simple truth!

I place the vent on the rear side of the cabinet when necessity dictates that I do so. And I insure that I’m using a powerful driver that is capable of overcoming the subtle effects of a rear cabinet location.

Vent noise: Regardless of where the vent is located in the system (front or back, top or bottom), if the vent(s) is too small in relation to the driver’s surface area (effective piston size), the air has the potential to vibrate at the vent faster than Mach 1.0. Since we are working with sound, note that forcing the air (sound) out of an orifice at speeds approaching Mach 1.0 (or higher) will not convert to accurate sound reproduction! When a loudspeaker has an undersized vent(s), and when the driver is operating at high levels of excursion, the frequency of vibration is forced into a resistive type compression, and the pitch must go up in frequency and produce massive amounts of distortion! In other words, it creates the dreaded vent noise anomaly! You will not have to worry about vent noise with my lineup of loudspeakers.

For example: Calmly blow into a flute, and you get a wonderful tone. In contrast, blow with twice as much pressure into the flute, and it magically jumps up a complete octave in pitch. If you have enough lung capacity and muscle strength, double it again, and it will jump up another full octave! I know… you don’t have a flute on hand to try this. Okay, simply calmly whistle a pure note through your mouth. Now, while holding that note steady slowly increase your lung pressure and hold the the pitch constant at the same time… Pretty cool, eh!?

Full-Range Driver Break-In…

Posted in Uncategorized on November 2, 2009 by tektondesign

My average typical full-range driver sale usually unfolds like this: The customer has just placed the order with me and tells me that he is very excited to receive the speakers and cannot wait to hear them. Then comes the inquiry. “Oh, and by the way, I hear that there’s quite a lengthy break-in period for full-range speakers. How long does this process take?”

The break-in process for pistonic motion transducers (i.e. the conventional loudspeaker) is an intriguing branch in loudspeaker design. Scientifically evaluating the transition from crisp, new transducers into fully functioning and matured devices has always been quite fascinating to me.  I have learned a lot and have implemented much in the way of design from the knowledge that I’ve gleaned from my observations into the subject. However, in my opinion, there is nothing in the full-range speaker movement that has generated more useless and foolish chatter than the so-called “driver break-in period.” It is also the primary header that dubious, and quite frankly, suspect loudspeaker builders cloak their mischief under, using it to pass off to you, the audiophile, their less-than-stellar work.

As I quoted in a previous post, “The greatest thing about speaker building is that anyone can do it and be successful, but the worst thing about speaker building is that anyone can do it and be successful!” So, audiophile buyers, beware!

A few years back, while attending an audiophile tradeshow, I purposely eavesdropped on a conversation involving an interested customer and a sales rep from the rear of a competitor’s (you would know the name!) demo room. Interestingly,  the company’s sales rep turned out to be the company founder and owner. After a few simple questions, the customer asked if there was a break-in period for the speakers. And what I heard next was about the biggest line of tomfoolery I’ve heard in all of my years in audio! “Yes,” he said, and proudly proclaimed that it takes up to 500 hours for their work of art to fully break-in, and that while new, the admittedly timid bass response was going to magically improve at some key point in the future! Not! Now, as a guy who has many years under his belt that are directly attributed to transducer engineering, I really cannot think of another audio-related conversation that was more offensive to me than hearing that one. Sadly, this company does sell a lot of speakers and people believe its twisted spiel.

500 hours break-in! Proper loudspeaker break-in is, indeed, long, and is to be expected. However, let me be perfectly clear – if a loudspeaker that you’re auditioning,  demoing, or have purchased doesn’t sound excellent right out of the box (excluding optimizing placement and final tweaking), immediately pack it up and send it right back where it came from, period! My offerings included!

Now, if you decide to purchase that drop-dead gorgeous pair of $20k High Jinks and choose to follow their strictly outlined homage-inducing burn-in protocol, here’s where it really gets serious. You are about to be sucked into the biggest psychoacoustic hoax in all of audio! I promise you that all of the burn-in and break-in time in the world isn’t going to make an inferior loudspeaker a world-class loudspeaker. What will happen is that over a period of time, the loudspeaker will continue to sound terrible. However, the “break-in” transition is really taking place within your brain. Through long term exposure, your ear/brain is literally psychoacoustically transitioning this inferior device to into a palatable and pleasant experience, and pretty soon, even the worst and most obvious design flaws are fully compensated or masked by the brain. An auditory illusion is far from world class audio! So, you don’t believe in auditory illusions?! Here’s an eerie one for you: http://en.wikipedia.org/wiki/Shepard_tone

Timid bass/poor bass weighting,  midrange shout (a well-known full-range manufacturer’s infamous attribute), a forward-sounding image, directional sound, and poor off-axis power distribution (all of which are common attributes of many full-range loudspeaker designs),  are simply the product of poor or even intentional design, and have absolutely nothing to do with break-in.

Full-range break-in – what you need to know:  All pistonic-type transducers have a very clear and predictable rate of change that occurs within the first few hours and within the extended hours of initial break-in. In the realm of credible transducer engineering, we see major changes (10-15%) occuring within the first 1-15 hours of break-in. This is the period where the major shifts normally occur. Beyond 15 hours, in a properly functioning and typical device, the process really slows down and small, incremental changes are typically observed over time. 

The Key: When a new transducer’s soft parts (cone, surround, spider, etc.) are crisp and tight, there is a specific level of transverse friction within a number of parts in the transducer. Once we get the driver working through its effective range of motion (far from linear), the transverse friction levels immediately begin to predictably drop, and the piston moves more and more smoothly with less and less resistance.

The full-range mystery: The break-in process (with all of its negative attributes) simply happens to be most intrinsically connected to, and is most audibly discerned through a full-range transducer. This is because a full range simply has the ability to augment the very subtle higher frequency centered distortions, squeaks, and squawks that a crisp new speaker is capable of producing.  Once again, if it is a full-range speaker and if it sounds bad out of the box, don’t wait for a miracle to happen; send it straight back to whomever you got it from because the speaker has serious problems. If it sounds quite good but has a very subtle graininess, or a few mild distortions, or the sound is crisp but still pleasant, then you’ve got a keeper! Sit back and be patient, and you will be pleasantly rewarded within 15-20 hours of moderate playback levels – this amount of break-in time will get you to about 80%-complete break-in. Beyond that, a functionally full and nearly complete break-in period of 200+ hours is quite reasonable and is to be expected.

Much more on this subject to follow…

Eric Alexander