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Human Speakers 81 dk Review

Rate this speaker:

  • 1. Poor (headless panther)

    Votes: 205 88.4%
  • 2. Not terrible (postman panther)

    Votes: 18 7.8%
  • 3. Fine (happy panther)

    Votes: 1 0.4%
  • 4. Great (golfing panther)

    Votes: 8 3.4%

  • Total voters
    232
D

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If science solved all our probelms we would live in a perfect world?

Science is a Method ... a method of identifying, understanding and then dealing with problems. A "perfect world" would be a world that did not have problems, not a world in which we needed to deal with problems, successfully or otherwise.

Basically, the Scientific Method is a way to reduce bias to a minimum, prevent emotion from clouding thought processes, and advance logic as the main priority in determining the value of an item or supposition.

However, there is another aspect of humanity. That is the side of emotion, or non-logical thought. Admittedly, this has given us art, music and philosophy. It has also given us superstition, wars, lies and ignorance.

As valuable as emotion is, it doesn't build integrated circuits nor digital recording stations ... or loudspeakers. Nor does it build satellites and derive pictures of the planets. Neither will emotion ever find a cure for cancer ... that's the bailiwick of science.

We need both sides, but we need less ignorance and superstition and more tangible benefits to humanity. I would appreciate that the next time I visit the hospital. :)

Jim
 
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fpitas

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Humans can hear up to around 19Khz right?
Some can. But after maybe 20 years old most people's high frequency hearing degrades.
 

IAtaman

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Some can. But after maybe 20 years old most people's high frequency hearing degrades.
Happened to have it in front of me :
1704282841320.png
 

fpitas

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We do live in a perfect world compared to 500 years ago.
Yes; history is scary sometimes. And the alternative to science is going back to living in a cave.
 

IAtaman

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Figure 9 of what? ;) In all seriousness, can you provide the reference? Textbook or paper?
I am genuinely curious (being an Old Guy with progressively Old Guy quality hearing).
Sure. It is from a presentation Sean Olive did for Danish Sound Cluster.

Figure 9 I shared is on page 41. I am afraid there is not much about age related hearing loss on the document though as it is mostly about headphone preferences.

 

fpitas

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However, all is not lost for listening enjoyment, as you get older. There are many aspects of listening that can still be valid if you have not been exposed to excessive sound levels for long periods during your lifetime. Distortion, particularly intermodulation distortion, can still be heard through much of the frequency range.

Well, that's good. I'd really miss the sound of good old intermod :facepalm:
 

adm

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Here are just a few random thoughts about the speaker under review:

1. Huw Powell's tweeter is an inverted (concave) dome, which you would see if you took the grills off. There is a trick to taking the grills off, which I will not share here. All I will say is do not force anything until you know what the correct method is. This tweeter was developed by Winn Burhoe and was first used in his EPI and Epicure speakers. Genesis Physics, which is spinoff of EPI, also used this same type of tweeter. The inverted dome tweeter is used today in a popular European line of speakers that I will not mention by name here. The company "borrowed" Burhoe's design. I have listened to several speakers from this company and find the highs to be somewhat harsh and fatiguing. This is the antithesis of my experience with EPi, Genesis, and Human speakers. Perhaps the somewhat declining response of the tweeter is to avoid this harshness. I would rather have the response err on this side than the other. I found an old review of the Epicure 11 speaker from 1976. The inverted dome tweeter in this speaker is Burhoe's original design. It is interesting that the frequency response of this speaker also declines noticeably above 10,000 Hz. This may be related to the dispersion patterns of the concave dome tweeter. There has never been any trace of harshness in any EPI, Epicure, Genesis, or Human speaker I have heard.

2. The driver module in the Human Model 81 and 81 DK is a time tested design that goes back to the late 60s. The drivers in the speaker under review are based on Burhoe's module, which was most famously used in the EPi 100. The EPI 100 recceived accolades for its accuracy and flat frequency response. It attained top ratings from Consumer Reports, which rated speakers based on flatness and uniformity of frequency response. I realize that the Human drivers are not exactly the same (theoretically they are better) but I think Huw Powell was after the same frequency response. Now it is possible that putting the same drivers in a bigger box makes the whole thing go awry but I have not been able to compare the original Model 81, which I own, and the Model 81 DK reviewed here.
 

mhardy6647

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Burhoe inverted domes -- the early years (EPI & Genesis) :)
(I don't have any of his later loudspeakers, nor any of Huw Powell's)

EPIsprings.jpg


Focal still makes an inverted dome tweeter AFAIK. Parts Express had - if memory serves - a relatively inexpensive house brand (Dayton) inverted dome at one point & for a while, but it's not in their current inventory. A quick googlin' hasn't turned up definitive information, but I am pretty sure I'm not inventing memories again ;)

I believe that our buddies ;) at GR used a Focal inverted dome in the little two-way Paradox loudspeaker kit. I had a pair in house for a while and thought they sounded quite nice. This particular pair had (perhaps) benefited from some XO modifications performed by their builder/owner (note the little switch on the tweeter escutcheon) :)

1704313401726.png
 

pierre

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The speaker is out of the box poor. I tried various EQs and I am not convinced that they will improve
things a lot. I settled on the one that flatten the listening window.
Scorewithout a subwooferwith a perfect subwoofer
Human Speakers 81 DK1.83.8
with EQ (flat LW)3.65.5
with EQ (flat PIR, score)5.96.9

When I optimise for a flat PIR or flat ER I am getting slightly weird results due to the non linear DI. I am sure I can improve things visually but tonaly that's unclear.

Results for flat LW
filters_eq.jpg


Results for flat PIR:
filters_eq.jpg


Flat LW EQ
Code:
EQ for Human Speakers 81 dk computed from ASR data
Preference Score 1.84 with EQ 3.60
Generated from http://github.com/pierreaubert/spinorama/generate_peqs.py v0.26
Dated: 2024-01-04-10:52:54

Preamp: -5.6 dB

Filter  1: ON PK Fc    58 Hz Gain +2.60 dB Q 1.65
Filter  2: ON PK Fc   211 Hz Gain +2.79 dB Q 1.17
Filter  3: ON PK Fc  1161 Hz Gain +3.00 dB Q 2.81
Filter  4: ON PK Fc  1954 Hz Gain -4.14 dB Q 3.00
Filter  5: ON PK Fc  3525 Hz Gain -1.51 dB Q 2.91
Filter  6: ON PK Fc 13186 Hz Gain +3.00 dB Q 0.58
Filter  7: ON PK Fc 15685 Hz Gain +3.00 dB Q 1.37

and EQ for flat PIR:

Code:
EQ for Human Speakers 81 dk computed from ASR data
Preference Score 1.84 with EQ 5.88
Generated from http://github.com/pierreaubert/spinorama/generate_peqs.py v0.26
Dated: 2024-01-08-10:46:31

Preamp: -4.1 dB

Filter  1: ON PK Fc    24 Hz Gain +2.98 dB Q 2.40
Filter  2: ON PK Fc   109 Hz Gain +2.34 dB Q 0.25
Filter  3: ON PK Fc   792 Hz Gain -3.29 dB Q 3.00
Filter  4: ON PK Fc  1083 Hz Gain +3.00 dB Q 2.37
Filter  5: ON PK Fc  1954 Hz Gain -4.08 dB Q 3.00
Filter  6: ON PK Fc  4342 Hz Gain -4.23 dB Q 0.87
Filter  7: ON PK Fc 16239 Hz Gain +2.99 dB Q 0.64
 
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beagleman

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15kHz (the upper limit for vinyl and FM radio) is more typical -- kids and some women can hear beyond that, and 10-12kHz isn't abnormal for men middle aged or older.
I have found that "Can hear" is quite different than "Can hear at the same level" as lower frequencies....
 
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beagleman

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Oddly I found some fairly good reviews of these speakers......

I see they measure somewhat poor in some key ways, but it has to make me wonder, at the same time....
 
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adm

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Oddly I found some fairly good reviews of these speakers......

I see they measure somewhat poor in some key ways, but it has to make me wonder, at the same time....
Could you please post the links or point out where to find them? Are they of the standard Model 81 or the Model 81 DK? There are good reviews of the standard Model 81. For what it's worth, the Model 81 received an average of nearly five stars on Audio Review. It also received a 9/10 and "nearly flawless" rating on "Wired," which I realize is not an audiophile source. I did find some measurements on Audio Karma showing some decrease in tweeter output above 10,000 Hz, although not as marked as what was found above. This may correlate with my experience of a slightly laid back, albeit very non-fatiguing, sound. However, the frequency response of the Model 81 overall is very smooth and linear.
 

bennybbbx

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at 86 db it have very few bass distortion and show only few resonances in the waterfall(i assume this waterfall is with 86 db ?) . When 2 speakers in stereosystem used level is then 92 db and then in hear damage region. most speakers have at low bass more distortion and more resonances at 86 db level as this speaker
 
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adm

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at 86 db it have very few bass distortion and show only few resonances in the waterfall(i assume this waterfall is with 86 db ?) . When 2 speakers in stereosystem used level is then 92 db and then in hear damage region. most speakers have at low bass more distortion and more resonances at 86 db level as this speaker
Thanks. The bass distortion of this speaker is not out of line compared to other two-way speakers with an 8-inch woofer. The severe distortion at 96 dB is not going to occur in real world listening situations, since no one is going to listen to these speakers at this volume. 96 dB is essentially a night club volume level. I will say that my standard Model 81s go relatively low in the bass for a small speaker with reasonable distortion levels. In fact, the bass response of the Model 81 is so good that it convinced me that I needed a subwoofer for the stand mount speakers in my main system. Keep in mind that these are relatively small two-way acoustic suspension speakers, not Klipschorns!
 
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jim1274

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Birds of a feather, and all that ...


Jim
I own a pair of the Burhoe design “Silent Speaker”scored from Human Speakers, their only offering that really caught my eye. Bought them quite a while ago from some reviews plus an interesting design, but mainly driven by his involvement in design of the energy 22:


They are nowhere near the Energy 22, that’s for sure, never expecting them to begin to compete with 22s, but sounded interesting enough to give them a try for the modest price. Been a long time since I played the Silent Speakers as a pair of stereo speakers, so can’t recall the particular shortcomings, but they hsve done duty as rear surrounds in my 11.1 ATMOS surround home theater system for quite a while.

There were a lot of interesting things happening on the speaker front in Canada in the early to mid 80’s, but that’s off topic.
 

bennybbbx

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Thanks. The bass distortion of this speaker is not out of line compared to other two-way speakers with an 8-inch woofer. The severe distortion at 96 dB is not going to occur in real world listening situations, since no one is going to listen to these speakers at this volume. 96 dB is essentially a night club volume level. I will say that my standard Model 81s go relatively low in the bass for a small speaker with reasonable distortion levels. In fact, the bass response of the Model 81 is so good that it convinced me that I needed a subwoofer for the stand mount speakers in my main system. Keep in mind that these are relatively small two-way acoustic suspension speakers, not Klipschor

What really impress is the low resonance in the cumulative spectral decay for such a big speaker . it is a closed speaker. I buy and keep a yamaha hs 5 this have less bass resonances as my other speakers and it sound best i have in bass clarity but it is open too. how the resonances sound can hear when you knock on the case in middle. human audio offer also a 61 model with pair price of 600 $. Seem also closed speaker design. A test of that i think also intresting. I i think better build 6 inch closed speaker it have in pysic less group delay in low bass and use if need a subwoofer.

here can see a high end neumann speaker with 5 inch and simular low bass https://www.audiosciencereview.com/forum/index.php?threads/neumann-kh120-ii-monitor-review.46362/
it have small case so can in theory have less resonances as a 8 inch speaker. keep in mind timescale of the spectral decay from the KH 120 II is 4-7 ms . 81 DK is 1-4 ms .in the kh 120 II is the volume higher but i dont think that the db more can have such a huge influence

I get in mind maybe the higher distortion at 96 db happen because of grill vibration. in low bass 96 db it is simular to other in distortion too. only upper bass and mid is higher as other. in test stand it was measure with grill. normaly every speaker get lower distorion above 200 hz.
 
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Head_Unit

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  • Wide frequency response enables...
Ah yes, I once worked in the Marketing department. 'Tis a magical place full of fancy, and a wondrous feeling infusing you that nobody will ever prosecute you or even call you on your sh!t.

Just now watching @raelnyc's YouTube documentary about Tales From Topographic Oceans, ad comes up "studies show" OMG can we please pass a worldwide law that anyone using that phrase ever again is subject to instant execution?!?
 
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