Some thoughts on ASR and the reviews


I’ve briefly taken a look at some online reviews for budget Tekton speakers from ASR and Youtube. Both are based on Klippel quasi-anechoic measurements to achieve "in-room" simulations.

As an amateur speaker designer, and lover of graphs and data I have some thoughts. I mostly hope this helps the entire A’gon community get a little more perspective into how a speaker builder would think about the data.

Of course, I’ve only skimmed the data I’ve seen, I’m no expert, and have no eyes or ears on actual Tekton speakers. Please take this as purely an academic exercise based on limited and incomplete knowledge.

1. Speaker pricing.

One ASR review spends an amazing amount of time and effort analyzing the ~$800 US Tekton M-Lore. That price compares very favorably with a full Seas A26 kit from Madisound, around $1,700. I mean, not sure these inexpensive speakers deserve quite the nit-picking done here.

2. Measuring mid-woofers is hard.

The standard practice for analyzing speakers is called "quasi-anechoic." That is, we pretend to do so in a room free of reflections or boundaries. You do this with very close measurements (within 1/2") of the components, blended together. There are a couple of ways this can be incomplete though.

a - Midwoofers measure much worse this way than in a truly anechoic room. The 7" Scanspeak Revelators are good examples of this. The close mic response is deceptively bad but the 1m in-room measurements smooth out a lot of problems. If you took the close-mic measurements (as seen in the spec sheet) as correct you’d make the wrong crossover.

b - Baffle step - As popularized and researched by the late, great Jeff Bagby, the effects of the baffle on the output need to be included in any whole speaker/room simulation, which of course also means the speaker should have this built in when it is not a near-wall speaker. I don’t know enough about the Klippel simulation, but if this is not included you’ll get a bass-lite expereinced compared to real life. The effects of baffle compensation is to have more bass, but an overall lower sensitivity rating.

For both of those reasons, an actual in-room measurement is critical to assessing actual speaker behavior. We may not all have the same room, but this is a great way to see the actual mid-woofer response as well as the effects of any baffle step compensation.

Looking at the quasi anechoic measurements done by ASR and Erin it _seems_ that these speakers are not compensated, which may be OK if close-wall placement is expected.

In either event, you really want to see the actual in-room response, not just the simulated response before passing judgement. If I had to critique based strictly on the measurements and simulations, I’d 100% wonder if a better design wouldn’t be to trade sensitivity for more bass, and the in-room response would tell me that.

3. Crossover point and dispersion

One of the most important choices a speaker designer has is picking the -3 or -6 dB point for the high and low pass filters. A lot of things have to be balanced and traded off, including cost of crossover parts.

Both of the reviews, above, seem to imply a crossover point that is too high for a smooth transition from the woofer to the tweeters. No speaker can avoid rolling off the treble as you go off-axis, but the best at this do so very evenly. This gives the best off-axis performance and offers up great imaging and wide sweet spots. You’d think this was a budget speaker problem, but it is not. Look at reviews for B&W’s D series speakers, and many Focal models as examples of expensive, well received speakers that don’t excel at this.

Speakers which DO typically excel here include Revel and Magico. This is by no means a story that you should buy Revel because B&W sucks, at all. Buy what you like. I’m just pointing out that this limited dispersion problem is not at all unique to Tekton. And in fact many other Tekton speakers don’t suffer this particular set of challenges.

In the case of the M-Lore, the tweeter has really amazingly good dynamic range. If I was the designer I’d definitely want to ask if I could lower the crossover 1 kHz, which would give up a little power handling but improve the off-axis response.  One big reason not to is crossover costs.  I may have to add more parts to flatten the tweeter response well enough to extend it's useful range.  In other words, a higher crossover point may hide tweeter deficiencies.  Again, Tekton is NOT alone if they did this calculus.

I’ve probably made a lot of omissions here, but I hope this helps readers think about speaker performance and costs in a more complete manner. The listening tests always matter more than the measurements, so finding reviewers with trustworthy ears is really more important than taste-makers who let the tools, which may not be properly used, judge the experience.

erik_squires

I guess my confusion about the ASR site is that there seems to be a certain measured criteria that noise when below the audible range that in a dark room I (or any real/ or perceived audiophile) wouldn't be able to differentiate this product from a more expensive product even if the more expensive measured better. 

Noise is just one parameter of performance, albeit, an important one that telegraphs other performance specifications.  If the frequency response of one system is rolled off then you are going to hear that whether noise is a factor or not.  Indeed, passive speakers are noise-free (when you are not feeding them a signal) yet there are vast audible differences between them.

If you mean all measured impairments are below threshold of hearing in both devices, then yes, in a controlled, level matched, repeated test, listeners would not be able to reliably tell them apart.

First, wouldn't that mean the more expensive product should get dinged in a review because even though it measured better the differences weren't audible and the relentless pursuit of better measuring products is of no value?

Not by me in the review.  Here is again the Mola Mola Tambaqui review:

 

It got the soccer panther (equiv. of golfing panther for European products).  Here are my conclusions after it topped all the charts:

"Conclusions
The Mola Mola Tambaqui DAC shows again that just because a DAC is designed from ground up, it need not perform poorly. It is actually the opposite with it performing at the top of the class with respect to distortion and noise.

Since I am not the one paying for it for you to purchase it, it is not my issue to worry about the cost. As such, I am happy to recommend the Mola Mola Tambaqui DAC based on its measured performance and functionality."

There are non-fidelity aspects of products that matter to some people, myself included.  There is pride of ownership, looks, support, warranty, resale, etc. that are valuable purchase criteria.  The key is to not confuse those things with sound fidelity.

To be sure, there is pushback from membership on how I can recommend such expensive devices since you can get similar performance for much lower cost.  My answer to them is that they can judge the product however they want (they get to vote in the poll that way).  My job is not to assess how affordable something is.  That, the readers can and do take into account.  I provide the missing information, i.e. performance data and they get to combine it with above factors to make a purchase decision.

I should say that I do "curve the grades" a bit when testing super budget products.  I will recommend a $90 amplifier with certain performance that I would not if it cost $9,000.

Finally, there are exceptions.  But above is how it works almost all the time.

Yet ASR continues to bring in new products after the peak has already been reached based on perceptive hearing,  To me then it appears that the pursuit is not about music but bragging rights regarding the  numbers or  else there is an audible difference beyond the perceived hearing threshold and ASR members can tell the difference.

People and companies send me products and I test them.  I don't go and seek them out myself.  People want to know if the performance is still great or taken a step back. 

Almost every review of state of the art DAC is followed by a number of people complaining what the point of testing them is as they all sound the same.  So your comment about "ASR people" is wrong.  Members know that a few manufacturers are in a race to product the least amount of noise and distortion they can.

Note that as of late, more features are being added such as parametric EQ in this Topping D50 III balanced DAC:

While maintaining start of the art performance for $229.

Finally, please note that the asian consumer electronics market demands fresh products.  Anything more than a few months old is "not good anymore."  If I were running these companies I would produce 10% of the products they do but their local market demands much more.  So we have embarrassment of riches as they say.