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

So tell me how you measure dynamics in a speaker? How fast the speaker is? Is that measurable? Mid bass punch under actual program material?

I had pioneer S1ex speakers. Heavy as hell and measured really well. Well they had 0 mid bass and no dynamics for anything other than acoustic rock… which they were amazing at! If I was just that or maybe a classical guy might have been perfect. But alas despite the amazing measurements and the bombshell cabinet it was a no go. My Focal 836w measured worse but similar.They sounded TOTALLY different real world with a multitude of amps both ss and tube.

Amir,

Where is your proof that an $80 DAC.....or any DAC for that matter, is transparent? 

There are multiple peer papers I suggest you read on this topic:

“Noise: Methods for Estimating Detectability and Threshold, ” Stuart, J. Robert, JAES Volume 42 Issue 3 pp. 124-140; March 1994
“Dynamic-Range Issues in the Modern Digital Audio Environment, ” Fielder, Louis D., JAES Volume 43 Issue 5 pp. 322-339; May 1995

If you don't have access to AES, you can read my quick write up in this article I published on audibility of small impairments. Or this video starting at 5 minute mark:

 

Once you read/watched those, take a gander at the review of the SMSL SU-1 $80 DAC. Here is its dashboard performance:

 

FFT spectrum shows distortion products way below threshold of hearing.  Even discarding simultaneous masking, those impairments are inaudible.  Dynamic range likewise covers threshold of hearing to playback level of about 115 dBSPL:

 

That is transparency for you, albeit, just at the edge with respect to dynamic range.  This $80 DAC cleans the clocks of many expensive DACs.  

Here is for example PS Audio DirectStream DAC which costs $6,000+

 

Distortion products are now at -80 dB which is a massive 50 dB worse than the $80 SMSL DAC!  It uses an output transformer which saturates and generates these harmonics.  Its noise floor is so high that it can't even clear 16 bit audio:

 

 You have no idea what transparency is since you do not listen.

Well, there are my listening tests of above PS Audio DAC:

Listening Tests
For subjective testing, I chose to use the recently reviewed and superb Monoprice Monolith THX 887 Balance Headphone Amplifier. This headphone amp has vanishingly low distortion and hence is completely transparent to DACs being tested. For the alternative DAC, I used my everyday Topping DX3 Pro 's line out RCA to Monolith. I then used the XLR input to connected the DirectStream DAC. Once there, I played a 1 kHz tone and used my Audio Precision analyzer to match levels using PS Audio's volume control. PS Audio claims perfection there ("bit perfect") so I figured they can't complain about that. :) The final matching was 0.3 dB difference between the two.

For headphone I used DROP + MRSPEAKERS ETHER CX with its XLR connection to THX 887 amp.

I started the testing with my audiophile, audio-show, test tracks. You know, the very well recorded track with lucious detail and "black backgrounds." I immediately noticed lack of detail in PerfectWave DS DAC. It was as if someone just put a barrier between you and the source. Mind you, it was subtle but it was there. I repeated this a few times and while it was not always there with all music, I could spot it on some tracks.

Next I played some of my bass heaving tracks i use for headphone testing. Here, it was easy to notice that bass impact was softened. But also, highs were exaggerated due to higher distortion. Despite loss of high frequency hearing, I found that accentuation unpleasant. With tracks that had lisping issues with female vocals for example, the DS DAC made that a lot worse."

You were saying?

 

Amir,

Your sonic test might be correct (you did not test it in with stereo speakers) and .... that is not a scientific test run by many people with many toys in many systems and blind tested, etc...which is what proof is (at least that is what you preach!!!). That particular DAC might be bad......I am glad you heard a difference (OMG!!! Amir says he hears a difference). Usually, you just say they are ALL transparent. How about wires? Have you listened to wires? Can you hear a difference? Have you listened to a ton of amps and premaps and DACs and heard all the difference us serious folks hear? Of course you have not....that would upset your ego to do serious listening tests. Can you hear what getting the cables off the floor does? What if you found out you were wrong all these years and every single brand of wire sounds different from each other (which they do). Very few serious audiophiles believe your crap. Oops, I said I was over and out....well, now you can have the last word.....the ego demands it....for we have to be right. Have fun in fantasy land.

How about wires? Have you listened to wires? 

Many times.

Can you hear a difference?

Very often.

Have you listened to a ton of amps and premaps and DACs and heard all the difference us serious folks hear?

Sure.

Can you hear what getting the cables off the floor does?

I haven't tried but I imagine electrons move slower the closer they are to the floor.

What if you found out you were wrong all these years and every single brand of wire sounds different from each other (which they do).

Same back to you.

Very few serious audiophiles believe your crap. 

Over 2 million people visit ASR every month.  That is almost an order of magnitude more than people that visit stereophile.com.  So pretty sure your claim is wrong but go ahead and provide data that back it.

 

 

 

Hey Amir, how many people eat at McDonalds? Further, these visits could be something akin to always looking at an auto accident as you drive by. Oh and comparing yourself to Stereophile doesnt help give you any credence. 

Just so I am clear, you hear differences between products that measure similarly so now you will tell us what would be an appropriate amount to spend on our equipment. Less is fine unless it is gear that you sell then the extra money is well spent. 

I would like to become a trained listener but will require a certificate to show my friends. Please help. Funny thing is that I will need to completely change the setup in my dedicated room to mirror your setup which runs contrary to what I have read, discussed with manufacturers and experienced in numerous rooms and shows over the last 40 years. Especially nice is the fact that I can now confidently include by big screen into my main system and improve my sound. Who new; hell who could even have imagined. 

Visitors to ASR, starting tomorrow, will be 2,000,001.