It is gullibility of human perception as a whole, hearing in this context, and no implied insult toward Dave. My apologies if insult has occurred.
I site Klippel in this instance as one of many including myself that have performed multi tone testing, listening with both ears and microphone.
All distortion is bad in reproduction. IMD is really bad, and operating a driver at wavelengths orders of magnitudes greater than driver's diameter is a great way to promote this.
I can provide plenty of pictures, references and details, but experiencing these evils isolated first hand is only effective way to learn what they sound like, and leads to better identification of them in program material.
Dave's apparent target with these speakers is phase coherence/lack of vertical lobing, and compromises with reduced linearity and power handling. Real performance metrics are only way to communicate this. I can't measure Dave's speaker performance, and I can't hear them, but real practiced knowledge leads to inference that as described, they have high levels of IMD from below crossover point to about 2kHz.
Dave is welcome to flesh this out with real measurements.
Regards,
Andrew
Regards,
Andrew
I certainly agree that IMD is "really bad" (if there's enough to hear it), but . . . common nominal 3"-4" drivers have cones from 2.5" to 3" diameter, so they are less than an order of magnitude smaller than wavelength down to 500Hz. or below, and excursion will be a modest 1-1.5mm for 105dB . . . is that OK by you ? ? ? I'm just not seeing the IMD contribution as being greater than, or worse than, the cone breakup induced distortion and the radiation pattern problems of the larger drivers commonly used up to and above that frequency . . .
The truth is that a mictophone is a tool. A very useful tool. It does not, though, "perceive" anything like the ear/brain. I have seen far too many people measure, look at the output and then "hear" what they saw.
In some respects yes. But a trained listener perceives things a mic has no hope of catching.
and compression driver systems with distortion >6% covering the rest.
This is unfortunately true, and the reason i build my own... little commercial stuff gives me the set of compromises that i prefer to live with.
And far too many amatuers (and even pros) do not understand what those measurements are telling them. Measurements are a tool to help the designer develop a design that does a better job communicating with the listener. They are an aid, not a proof. Our measurements are still too primitive and without the required established coorelation with human perception.
Not a set of listeners that i belong too.
Or i have enuff practical experience to know the limitations of those "measurement" excercises.
All too true. And in ways you haven't imagined... like the guy who looks at the graphs and hears what he sees and not what he hears (and is actually there)
I am well familiar with that. And one should be aware that careful selection of partnering amplifier can cancel much of that second order distortion.
Real drivers, artifical signals, results that have to be interpreted and have little established correlation yet to what the ear/brain perceives.
dave
The driver i am using has the HF characteristics of a 3/4" dome.
Dave will keep his measurements to himself, they are tools for my use, not for other's misinterpretation. Evaluation of a speakers should happrn in the room, with the kit, and by the ears it will be used with
Just as i have, till now, declined to comment on the measurements that Andrew has posted of his speaker, which has me wishing to hear if it has the qualities i fear it has from my interpretation (or misintrepetation) of the pictures/graphs.
dave
Says it all. Simply listening to the pass off from Oboe to Clarinet in the third movement of the Gran Partita tells me more about a speaker's midrange behavior than all the charts and distortion sweeps. The measurements certainly help in figuring out what's happening when it's "wrong", but they're still not enough to tell me it's going to be "right".
A 3way is a 2way with subwoofer.
If you do it right you shout end up with better sub-bas and cleaner midrange with the 3 way. Because the mid-driver has to work less hard, and the woofer can be the right size.
cross it low for less interference problems and constant directivity.
If you do it right you shout end up with better sub-bas and cleaner midrange with the 3 way. Because the mid-driver has to work less hard, and the woofer can be the right size.
cross it low for less interference problems and constant directivity.
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I would say much of it depends on how loud you play
best mid is a 4-5" type
crossing low, it might be better to use a 6"
if you play loud, I would think twice about crossing the mid bery low
that said, a small 2way with a 5" can at times sound surpricingly good
I have long wanted to try a 2.5way with 5" woofers
but it easily gets expencives
maybe some day when I get tired of big speaker
subwoofer ? yeah, that too, but also expencive
and my next speakers are probably bigger than any I have ever had
best mid is a 4-5" type
crossing low, it might be better to use a 6"
if you play loud, I would think twice about crossing the mid bery low
that said, a small 2way with a 5" can at times sound surpricingly good
I have long wanted to try a 2.5way with 5" woofers
but it easily gets expencives
maybe some day when I get tired of big speaker
subwoofer ? yeah, that too, but also expencive
and my next speakers are probably bigger than any I have ever had
THis is something that has becoming much clearer with the advent of acceptance od the subwoofer as a separate entity.
Toole & Geddes have really rammed that home.
dave
You can make a 3 way crossed at 800hz en 3000hz.
I would choose 100-200 and 1500-2000Hz for a fine 3 way. The raised 3 harmonic under 100Hz of a small driver shout be reduced with a 3 way and give cleaner mid. That is where we are the most sensitive.
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yes and no
I have problems understanding that 'subwoofer thing', or the new perception of what it means, a subwoofer
when the subwoofer was 'invented' it was solely intended to as ad-on unit, and crossed no higher than 50hz
so in that sense I would say a 4way is 4way, and thats it
crossover points would be much like 3way, just with yet another crossover point somewhere in the middle of it all
ofcourse you can build a 3way with sub, and call it a 4way, if you like
and it is a kind of 4way, kind of
I have problems understanding that 'subwoofer thing', or the new perception of what it means, a subwoofer
when the subwoofer was 'invented' it was solely intended to as ad-on unit, and crossed no higher than 50hz
so in that sense I would say a 4way is 4way, and thats it
crossover points would be much like 3way, just with yet another crossover point somewhere in the middle of it all
ofcourse you can build a 3way with sub, and call it a 4way, if you like
and it is a kind of 4way, kind of
whether it is a 2 way or a 15 way, if you add a driver AND a crossover point you are adding... So 2 drivers, 2 crossover points... 2 way, 3 drivers 2 crossover points.... still a 2 way, 3 drivers, 3 crossover points, its a 3 way... in its purist sense a subwoofer is a stand alone unit. If you want it to be non directional in a room, it would need to be crossed below 100 hz. If you add a subwoofer to a speaker built in, you changed or added a way ie, 2 way goes to a 3 way... 4 way goes to a 5 way etc.
Should we talk about a 2.5 way????
Should we talk about a 2.5 way????
kk
because im going the 3 way route.
woofer from 30hz to 300 hz is active. crossover points are 300hz and 6khz. I believe that if you are able to design a speaker without a crossover between 300hz to 2.5khz, the phase coherance is not really a issue?
noo, a genuine 4way has two midrange drivers....and thus 'could' have a smaller tweeter
you are entitled to believe that, but is a belief only
its really a myth from old days when people had no idea about how to make a good crossover
actually, 'old days' is not so long ago
a midrange crossed at 6khz is more like a fullrange with supertweeter, and a woofer helper
it can sound very good too, but its a different thing
I think it does matter what we call it, how we look at it....it will have influence
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