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.
Amir calls himself a professional listener. He sets up "one" Magnepan LRS panel and calls that his listening experiences for the common audience. He then claims his site has millions of views. I wouldn't be one bit surprised if most of those views were readers wondering what this guy has trashed next.
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@tvad you are correct. I have done exactly that with Roon for several rooms at home. Creating your own filter is not as easy as just using one that already exists like for headphone models but every room is different so you have to create your own. REW is very powerful but a bit technical and complex to get one’s arms around initially. Luckily there are guides available via Roon forum that takes one through the process if interested. I highly recommend it as both a learning experience and a very practical way to help bring out the best in most any system Now, Imagine a site where someone reviews lady’s handbags on measurements only. You might find the most functional bag for the best price but how many ladies buy handbags that way? The boutique/designer handbag industry would be in an uproar. 😉
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I think you measured using a single frequency at steady state response at one 1KHz. It might not reveal the affectiveness or deficiencess of the power plant. It is not even close to being adequate. A better test would be using a square wave input then look at how the output follows the input square wave with different load - using high current and low current load. This would be a more difficult test than steady state. Also make sure the partner amp that you’re using for the test is not the limiting factor. An outlaw amp probably is not really a good candidate. You probably need a better amp. I think the flaw of most of your testing is because they are done in the frequency domain.
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That would be wrong. Here is a full frequency sweep of the P12 Powerplant:
Full frequency sweep is performed from 20 Hz to 20 KHz.
Seeing how the above measurement showed that the P12 increased noise instead of decrease it, I say your assessment is incorrect.
That is still "steady state" by your definition since there is no discontinuity in the signal. That aside, you can't have square wave as a valid audio signal since it has infinite bandwidth (Fourier Theorem).
The amp was not the limiting factor if you read the review of PS Audio P12 Part 2: Here is the amp by itself, with continuous power and burst:
Now see how power lowered while using the P12:
Both burst and continuous power reduced. This was easily explained due to use of current limiting in P12, contrary to company marketing and understanding of their CEO and founder. We can see this in power sweep as well:
Your thinking is wrong. All testing is done in time domain. The graphs are shown in frequency domain since it is hard for a human to tease out the noise and distortion from a waveform display in time domain. Keep in mind again that based on Fourier Theorem, time and frequency domain are interchangeable. Frequency domain also has a major advantage in that much of our psychoacoustic knowledge is in frequency domain due to how our ear works with a bank of auditory filters. Bottom line is that P12 is not a true power regenerator and has current limiting which reduces performance of amplifiers. Testing clearly showed this. With non-amplifiers, it simply did nothing useful since those products have their own internal filtering and run on DC, not AC. Note that company doesn't provide any of the measurements I provided. Had they done this type of testing, they would have a) seen the degradations P12 introduces and b) realized it makes no difference to output of audio products. |
Pretty absurd, isn't it? Even more absurd is you go to your doctor wondering if you have broken your arm. He turns on this machine that outputs invisible rays. Yet he claims he can get a picture out of that showing your arm is broken!!! They must create these X-ray pictures in photoshop! Not everything in audio needs to make lay sense to you. Same as X-ray being able to go through your body and show your bones. You trust your doctor to know that X-ray can show you that information. You should trust people who have research single-speaker vs stereo vs multi-channel and found that single speaker is far more revealing of speaker flaws than when you add more channels. I have a video on that:
My job as a reviewer is to give you accurate assessments of products and single speaker is a critical component of that. Use stereo for enjoyment but if you are evaluating speaker performance, do it with a single one. |
