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

@mahgister I've read most of this literature, including the new (for me) Kunchur paper (his previous paper on cables is neither relevant nor well-designed). I'm not certain, however, as to how to parse your long digressions on these topics.

For instance, if we can measure noise and distortion in audio equipment, it is valuable to reduce or eliminate it in the reproduction chain regardless of whether there are potentially complex heterodyning/non-linear ultrasonic interactions or whether hearing capabilities can be shown to have greater sensitivity than assessable via Fourier analysis.

If there is an additional claim that perhaps cables and other tweaks that are measurably irrelevant to the signal reproduction can actually be heard, it is still in the best interest of general epistemic humility to remain skeptical until such measurements/ABX hearing results (with the LTM/STM refractory suggestions in Kunchur maybe) can be found.

So, in the meantime, we just get great measurements from ASR and can merely speculate that something might be missing, not that it demonstrably is missing.

So the distortion figure of an amplifier is in itself of little use. A spectral specification would be more useful, but is rarely given.

I give that in every dashboard view of audio electronics I test.  This is the response of a $10,000 Bricasti DAC:

Now you can apply the very analysis he is performing with respect to power of harmonics.  Without my measurements, you would have no idea.  Therefore, my work is sanctioned by him.

 

I think Amir/ASR does an EXCELLENT job of measuring and evaluating all sorts of audio equipment. Another reviewer who does excellent work is Erin’s Audio Corner. I trust reviewers who do actual measurements. Although such measurements are not the last word they are a good baseline. Everyone’s ears and listening rooms are different but those baseline measurements can give you an idea of what to expect. Nothing is perfect but who performs reviews better than Amir or Erin?
 

The reviewers I don’t like are the guys on YouTube that only give opinions on what they hear. One of those reviewers actually asks his wife’s opinion. That type of review is useless to me.

I think Amir knows how to use his equipment.  What it means is another thing.  Baseline measurements tell you practically nothing about how something sounds.  According to Amir.....all amps sound the same as long as they meet his SINAD number.....same with DACS, preamps and cables.  Nothing could be further from the truth.  Basic SINAD and the spectral of distortions are just a couple of a million things in a product that affect the sound.  I have been doing serious listening tests to passive and active parts since the mid 70s.  I was one of the first people to do straight wire bypass tests on wire.....back in the 70s as well.  No, no wire passed the test.  All jacks, wire, solder, damping, shielding, capacitors, resistors, switches, relays, fuses. power cords, etc to infinity ALL change the sound of an amp....and NONE of the things I just mentioned CAN be measured.....NONE.  It is so juvenile and simplistic to think that a certain distortion measurement number means a certain pure sound.  Only the deaf or stubborn would claim such.  You have to listen to know how something sounds.....this is the simple truth.  Those that follow Amir are and were already disposed to cheapness, a super "scientific bent"....and cynicsm about the high prices of some audio gear.  Amir is their savior.  He claims he KNOWS.....but he is ignorant of the truth.  Look at the reviewers/listeners who listen.....they all move on from the Topping DACs......dry, two dimensional and uninvolving......not REAL...and I am not talking tube colorations needed......just a more natural sound.....like real instruments in real space......goosebump city.  

Does not mean you cannot get good sound out of a Topping stack and generic cords.......yes, the lowest levels of gear today are really good.  But if you want to hear what brand of string is on the guitar, and you want to have goosebumps higher than Everest......you will need to go higher than SINAD measurements can take you.....and to do that.....you must listen.

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