So far in the test, what seems to be noticeable is about directivity, not timbre or micro-dynamics, etc...
but that was expected (directivity).
Not being able to notice differences in the overall sonic signature from each drivers, that was not expected. At all.
Of course, we can add distortion as something noticeable since we WILL most probably notice a certain level of distortion if the drivers are pushed too hard. But at comfortable listening levels, within driver's limits, maybe that's not a real factor to consider...
So directivity and distortion. Then what ? I only see the emissive surface that is left potentially noticeable as well. I'll give it a try, of course.
but that was expected (directivity).
Not being able to notice differences in the overall sonic signature from each drivers, that was not expected. At all.
Of course, we can add distortion as something noticeable since we WILL most probably notice a certain level of distortion if the drivers are pushed too hard. But at comfortable listening levels, within driver's limits, maybe that's not a real factor to consider...
So directivity and distortion. Then what ? I only see the emissive surface that is left potentially noticeable as well. I'll give it a try, of course.
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At this stage I actually doubt it!
I think freq response is king, then distortion/headroom and directivity.
Thanks for your hard work on this. It is already affecting decisions I am making.
I recently built a synergy horn design using a full range driver (SB65WBAC25) to cross to 8 inch woofers at about 500hz.
It is documented on this site (XBush speaker), and I have written in that thread how I felt the SB65 was better in the mid-range than the scan-speak 12MU and volt VM752 that I could directly compare it do. (That is a £20 versus £200 versus £550 midrange driver!)
Now I put this down to a lot of things (3-way direct radiator design versus synergy horn etc, etc) - but certainly not to the fact that the drivers themselves might be largely similar when EQ'ed......
At this rate I will be selling all my expensive drivers....
That's entirely his point though.
Currently you are listening in one position and using an EQ and measurement method that will give you a flat response that also includes the room.
The room aspect is largely dependent on the off axis energy and the reverberation field that is energised as a result. With your method you are EQing the room.
The RS225, for example, will start to show falling off axis energy a little above 1kHz and all the way up to 7kHz it will be beaming like a lighthouse.
Something like the tiny full range drivers, you've also got in this test, will most likely only show these effects from around 3-4kHz and still offer decent off axis performance up at 7kHz.
Then we've got the compression driver with an off axis response dictated entirely by the horn you connect it to.
For arguments sake all of these drivers could have a perfectly flat frequency response on axis, but when the rooms average response is also mixed in (as you are doing) you are going to start seeing some of the power response and are going to EQ based on that. This is generally seen as a huge no-no.
As has been said many times before you need to be using gated measurements that remove the room from the equation and EQ based on that. Using pink noise and 1/3 or 1/6th octave RTA etc might have been popular years ago but literally no one uses that as a measurement technique these days, especially for crossover design and fine driver optimisation.
Don't get me wrong pink noise RTA measurements etc do have their uses but this is not one of them. Not if your are primarily after accuracy.
An example of this would be for stereophile's review of the KEF Blade 2.
KEF Blade Two loudspeaker Measurements | Stereophile.com
In figure 4 you can see the composite frequency response that is arrived at using gated measurement techniques. As you can see the frequency response is impressively flat.
If you look at figure 7 though you will see something quite different. This is how the loudspeakers frequency response looks, or rather the overall energy distribution in-room looks. The red trace is the KEF. See how its response is now falling? This is due to the KEFs off axis response. If you were to EQ this to flat you'd end up with an aural problem.
Now this is exaggerated because the measurement in figure 7 is spatially averaged, meaning the mic position was changed, to show exactly what the overall energy within the room is like.
Here in figure 7 we've got a lot of the room + direct sound from the loudspeakers. In contrast figure 4 contains pretty much 100% direct sound and none of the room.
What you are doing with your measurement technique is a mixture of the two, which isn't really any good for anyone. You need to be using gated measurements and in a room the size of yours, if properly done, you should be able to get good data down to around 300Hz anyway.
I do understand all that.
Don't get me wrong: i'm not saying i'm using the ideal methods for speakers design, real listening, etc...
What i'm saying is:
Whether or not the room effect is in the equation, it's still amazing being able to MIMIC a driver with another completely different driver.
and to answer more directly your point/questionning:
i still believe the PROPER way to do what you're talking about, is in a real anechoic room. You want to be sure to get rid of the room effect in the measures ? Get rid of the room! 🙂
i still believe the PROPER way to do what you're talking about, is in a real anechoic room. You want to be sure to get rid of the room effect in the measures ? Get rid of the room! 🙂
But then again, we all must deal with room effects somehow. That's the realistic view of the whole thing, nobody's living in an anechoic room...
In fact, the room/set-up i'm using for testing at this moment is probably closer to an ''anechoic effect'' than most people's rooms.
- Chair/mic is nearfield (1.65m)
- carpeted floor
- very high ceiling
- very far side walls
- wall behind covered in 35kg/m³ foam
...and 360hz-7.2khz band
I mean, come on...
We're not talking about a subwoofer pounding in a ceramic-covered bathroom here.
Granted, there is still room effect in the equation. But i really don't feel it could change the results we had so far. I just don't.
That being said, if Tomahawk wants to bring his equipment (along with his Lynx Aurora) i'll be more than happy to try it. Just don't expect too much regarding any different results 🙂
In fact, the room/set-up i'm using for testing at this moment is probably closer to an ''anechoic effect'' than most people's rooms.
- Chair/mic is nearfield (1.65m)
- carpeted floor
- very high ceiling
- very far side walls
- wall behind covered in 35kg/m³ foam
...and 360hz-7.2khz band
I mean, come on...
We're not talking about a subwoofer pounding in a ceramic-covered bathroom here.
Granted, there is still room effect in the equation. But i really don't feel it could change the results we had so far. I just don't.
That being said, if Tomahawk wants to bring his equipment (along with his Lynx Aurora) i'll be more than happy to try it. Just don't expect too much regarding any different results 🙂
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You're most welcome. 😉
Yes i agree.
And i might as well sell my expensive drivers. But i'm not yet jumping to conclusions, there is many things i'd like to check/test before, starting with a proper source/DAC. It's coming.
Well, then prove it.
Organize an identification blind test with electronic components and prove it.
after that one, i'm about to organize one with DACs, but i'm not very interested regarding amplifiers because i feel the chances are much better with the DACs...
I'd like to point out something important:
I'm getting these results with very basic EQing.
We're talking here between 3 and 6 bands for each drivers. That's not much.
Also, i'm not tweaking the thing to the death...
That, and also the fact that i'm using 1/3 octave resolution RTA, makes it even more surprising that people don't spot the difference.
...basically, if people WOULD BE ABLE to spot the differences, one could point out the lack of EQ, etc... But it's not the case here.
To make some analogy:
The Large Hadron Collider discovered the Higgs Boson in 2012.
About 3.5 TeV per beam was needed to find it.
If you find it with 3.5 TeV, you proved the whole thing. It's done.
No need to go 20 TeV. But if it was not found with 3.5 TeV, then you need to move up.
In our case, maybe the basic EQing/measure is enough to blur the hearing capacities of 99.9% of people.
Maybe the most extreme of EQing and measures will achieve a 99.999999% results... But that's not the point.
The point is: most people (not 99.9% yet!) are already totally confused with some ''lousy'' EQ and measures. That is nothing short of mind-blowing.
You would be wise to listen to 5th element and other and use gated measurements. Though your room has a decent size, listening position is close and there's some treatment (though very bandlimited), you will still end up EQ'ing the room quite a bit if you aren't using gating. This is not something you want, you want to stick to EQ of the drivers alone.
EQ of the room where it's not minimum phase will by the way lead to phase issues. One of the reasons auto room correction often sounds so unnatural and weird.
EQ of the room where it's not minimum phase will by the way lead to phase issues. One of the reasons auto room correction often sounds so unnatural and weird.
Jon,
If I go to MTL area in September long weekend, I have to go see you and bring some good amp that will make you want to trash your classD amplifiers...
Been there, done that, tried to switch to class D amp and ended up selling them at loss without any regrets.
Odds are you 'll wanna sell yours too.
I've just bought some transducerlabs beryllium tweeter if you wanna compare them with your "ultimate tweeter test".
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You are still using class D? Midrange come alive with class A tube amps or Firstwatt amps, or the likes of it. I tried some cheap class D boards, then went to a friend who bought a $1000 class D amp. It sucked in the same way, only more because he paid so much. Jesus!
Poor Ole. Should have listened to me.
Poor Ole. Should have listened to me.
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Guys, would you bet the amount$ needed to organize a blind test... that you won't be able to spot the amplifiers once level-matched ?
If so, i'm in.
Won't waste any money if i'm right, though.
If so, i'm in.
Won't waste any money if i'm right, though.
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The amplifier with the absolute lowest distortion on the market is a class D (Hypex Ncore). Lower distortion than any class A amp. A lot of audiophile subjective nonsense and myths out there.
The amp JonBocani is using is good enough to reveal clear differences between drivers.
The amp JonBocani is using is good enough to reveal clear differences between drivers.
Subjective nonsense is the key here. A lot of it this month
I'm questionning my whole audiophile past... No seriously. About 25 years of speakers design/DIY down the drain. Sort of.. 😱
...Or i just grew old and i'm deaf.
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More of a chance to spot differences between drivers than what you are using now. 🙂
It will still be difficult, we did see the room, not bad at all! Most of us have to live with much worse rooms.
The band pass makes it a challenge too. I'm not at al surprised by the outcome so far. Just curious if there's
a change if you start to "feather" the EQ instead of "hammering". (based on the time difference between the
two methods).
You're basically all set up, it wouldn't be that hard to run a test like that...
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