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

clips that show the ability of the speaker to do so with sub-bass content.

How fast the speaker is?

There is no such thing. Every sound has its frequency and speaker driver needs to only be "fast" enough to play that. The perception of slow bass likely comes from non-flat bass response of the speaker combined with the room it is in. Both of these are measured using frequency response.

(facepalm) Absolutely Wrong!

@mofojo , A low info computer science undergrad (gpa = 2.0)/programmer grunt wouldn’t have had any coursework/tech electives in vibration, shock mechanics, etc. That’s the domain of the engineering phds (aerospace, MechE, etc), typically, i.e. guys who end up in env.test/sim engineering, spend a lot of time with setting up tests, instrumentation, sim models, validation, etc.

Don’t believe a word coming out of a low aptitude computer science grunt. His only job is to write 2 stupid lines of code without understanding anything about what it’s for.

It is a very simple ring down requirement (threshold) you can pose in the time domain and analyze it for any driver. It will be different for different drivers. In a parallel engineering world, it is done all the freaking time when mechanical shocks (impulses, whatever) are performed for testing components with ED shakers, res plates, etc.

 

Whelp... In all the time I've talked to audiophiles the issue of speed keeps coming up, especially with subwoofers.  While I understand why audiophiles have a hard time integrating subwoofers to any speaker and room, the speed issue seems to not be a speed issue but a bass mode issue.

Keep your subwoofer small and you don't wake the dragons, so they "sound" faster.  they aren't faster, they are less dangerous. 

OTOH, what IS real is that high-passing drivers makes many, especially mid-woofers, really shine.  The bass, where they have output but at considerable distortion, gets moved to drivers with much lower distortion at the same db/Hz. 

1. Why do people wonder why someone who has a thread started that is critical of both them and their entire website bothers to respond? Someone has a problem here and its not the one being challenged.

2. If someone feels so strongly negative about another’s approach, rather than categorically trash the person (an increasingly common practice these days as more people follow bad examples they are exposed to daily), maybe start your own website that does it better your way and see where the cards fall? Otherwise best to stay away from personal mudslinging if one cares about leaving a good impression. Challenge the specifics of what is being asserted that you disagree with, rather than the person.  Offer a better way perhaps.  IT's not a crime nor a felony to at least try to take a scientific/measured approach to something, especially something like hifi gear that is purely a result of technology done right or wrong to various degrees.

I’m going to go out on a limb and assert @erik_squires loves to push buttons. Just saying. Not a bad thing in of itself but one should not be surprised at what ensues. IF it takes a bad enough turn, any thread can be removed if deemed to be contrary for the common good of all.

How does "ring down" equate to "fast"?

Liberties with semantics being taken here?

There is such a thing as "slew rate", a metric with very specific technical meaning in electronic signal processing and the time domain that I would assert clearly does matter, to the extent which it can be accurately measured in practice.  Certain op-amps designed to perform well in hifi applications are known for exceptional slew rate measurements. 

Slew rate - Wikipedia