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

@markwd 

I left out preferences in listening pleasure as well as the rooms gear is listened to, it being so obvious that I felt it need not be mentioned. 

This reminds me of a review Ron did over on New Record Day about (I think it was) a Dali speaker. His measurements showed a rather large frequency spike around 12 or 15 KHz that didn't manifest itself as shrill, etched or zingy. He spoke with Dali about it and it was designed in. He found that it had lots of air, ambience and detail without the negatives. The speaker had a lively and not fatiguing quality that made listening a pleasure. 

I find it odd that many who are into measurements cite the Harmon/Toole studies about preferences that were pleasing to the general and uninitiated public, resulting in that V curve which is not all that accurate and faithful to the original that's held up as something to aim for. So which is it? Accuracy or pleasure?

The answer is it has to be both. Strict accuracy leaves out the variables we haven't nailed down as of yet, small and elusive they may be and to dismiss it as mysticisms and deepenings smacks too much of hubris for my liking.

YMMV. Mine does.

All the best,
Nonoise

Post removed 

@nonoise 

Ok, so we agree that there are preferences and those preferences may not correspond to the Harman curve, for instance, which is an aggregate measure of preference. In DACs and amps the notion that there is a preference for distortion artifacts is simply at odds with valuing accurate reproduction, however. I'm fine with that. Folks be free, always, but I still have no clear idea why anyone gets bent about basic accurate engineering that targets fidelity or make astonishing claims without evidence about cables or power conditioners?

We do have a disconnect with scientific reality that is itself hubristic because it strays from (repeating myself) epistemic humility by suggesting all these listening preferences supervene on basic measurable facts about music reproduction.

@mofojo 

Ummm, no, that is wildly inaccurate. Please read some ASR reviews and read/watch the primers to get an understanding of how measurements are performed. There is no pink noise, but there are various frequency response measurements, very similar to the way that DIRAC or other room calibration approaches work because that is exactly what they are emulating.