"frequency response of the driver and mic response are put out of picture by normalization"
?
//
It looks huge on the pictures. Is it really 12" - didn't you scale it somehow?
its 15" = 390mm and 190mm deep. I'm pretty sure that's what you gave me. What on earth have I made!
How a system design interacts with your expectation is indeed a highly relevant factor. For example a lower DI is going to enhance the reproduction of live recordings due to its greater "spaciousness", but will degrade studio recordings because the low DI is going to degrade "image". These are tradeoffs that simply cannot be avoided and will play very much into your "expectation".
Oh, I should probably check again, I remember 12", but definitely you should check the bigger one before you start it! Something may be wrong somewhere
Edit: Yeah, it was really 15". My bad, sorry. Well, that's a nice piece of waveguide you have.
Last edited:
I don't understand the question.
Measured_SPL_at_0_deg = DUT_at_0 + MIC
Measured_SPL_at_10_deg = DUT_at_10 + MIC
Measured_SPL_at_20_deg = DUT_at_20 + MIC
...
Data normalized at 0 deg:
Normalized _SPL_at_0_deg = DUT_at_0 + MIC - (DUT_at_0 + MIC) = 0
Normalized _SPL_at_10_deg = DUT_at_10 + MIC - (DUT_at_0 + MIC) = DUT_at_10 - DUT_at_0
Normalized _SPL_at_20_deg = DUT_at_20 + MIC - (DUT_at_0 + MIC) = DUT_at_20 - DUT_at_0
...
You see, no MIC response in the normalized data.
Agreed. The most extreme example I can think of is playback of 1920s recordings. (seems that it's what I spend most of my time listening to these days). Through my mono 1m wide 1m deep exponential horn they can sometimes come alive in a quite spectacular way. Detail, fizz and pop and sheer pleasure of performance - makes you wonder about 100 years of progress. I don't need to be told that they would be 'better' through the Genelecs!
Of course, that's not the whole story, which is why we are here.
I do think there is an issue with what we expect 'entertainment' to be in the modern era. Music can be so meaningless and uncommunicative these days - and of course we can easily design, make, and are sold equipment to reflect that. Walking round Munich show last year was an eye opener. The very very few rooms that were listenable seemed to be reflection of the aesthetic tastes of their designer's passion for their love of music, culture and taste.
In other words they are best listened to on 1920s equipment...
I suppose there can be some truth to that.
Last edited:
When I used to audition my speakers at my home I noticed that people who brought their own music that they were familiar with were always pleased. But when someone showed up and just asked "play me something that will blow my socks off" they were always disappointed. It's all about expectation and familiarity.
My good friend Dave Clark (RIP) had a completely restored 1950's record player and tape system. He loved to listen to his 1950's recordings on it. I just found that it sounded like a 1950's system playing poor records. I just couldn't get the attraction.
Another example that always got me was when I played an original "Take Five". One guy said "Where did this recording come from, I've never heard this version before." Except that there aren't different versions, only one. Had the system sounded like a 1960's one I am sure that he would have recognized it, and probably like it better. Nostalgia plays a big role in audio perception.
My good friend Dave Clark (RIP) had a completely restored 1950's record player and tape system. He loved to listen to his 1950's recordings on it. I just found that it sounded like a 1950's system playing poor records. I just couldn't get the attraction.
Another example that always got me was when I played an original "Take Five". One guy said "Where did this recording come from, I've never heard this version before." Except that there aren't different versions, only one. Had the system sounded like a 1960's one I am sure that he would have recognized it, and probably like it better. Nostalgia plays a big role in audio perception.
Last edited:
"Reasonably flat" and smooth DI is what sounds perfectly fine to me as we typically don't want the power/room response to be flat anyway (bmc0 being the curious exception
I'm still not sure I understand this falling power response thing... Despite my speakers having flat power response from 1kHz-15kHz, the in-room response very closely follows a -0.4dB/oct line, which is in the range that Dr. Toole states is ideal for home theaters and listening rooms:
(from this post on AVS Forum). If you only consider the data above 1kHz the slope is more like -0.2dB/oct, but the difference between the two over that range is very small (around ±0.3dB). Modifying the direct sound to achieve a power response target just doesn't quite sit right with me.Floyd Toole said:
Last edited:
I really wonder how he got those numbers (0.4 to 0.5 dB/oct). Don't you know? That would be only around 1.5 dB of downward tilt between 1 and 10 kHz, which is surprisingly low value to me. I would expect more, like 3 dB.
Loudspeakers like yours, with their constant DI, are still rather rare and it may be difficult to integrate them into the "circle of confusion", the more that a flat in-room response was never a standard anywhere, as far as I know. They radiate more high frequency energy than most so I'd expect you would tilt the response downward a bit. Yet, it's not the case (-0.2 dB/oct is almost flat to me).
Loudspeakers like yours, with their constant DI, are still rather rare and it may be difficult to integrate them into the "circle of confusion", the more that a flat in-room response was never a standard anywhere, as far as I know. They radiate more high frequency energy than most so I'd expect you would tilt the response downward a bit. Yet, it's not the case (-0.2 dB/oct is almost flat to me).
Some people, especially on French forums, have extensively experimented with many horn types in different spaces with different degrees of treatment.
In order to make a (subjective) judgment about the effects of directivity.
Explicit reference was made to the work of Dr. Geddes. Notable was the finding that a high degree of (constant) directivity in the top octave in average (untreated) spaces was experienced as unpleasant/tiresome due to the reflections.
Last edited:
I generally agree to this but would not directly relate these finding to directivity at all. Directivity is a good thing but if a horn radiates 90 deg or a similar range in a listening room it produces more problems than it solves and a round horn radiates "uncontrolled" in all directions of the room and produce reflections from the floor and ceiling. Here in this thread directivity seems to be the holy grail but to control the shape of the wave front to be focused in the listening plane where one or a few people listen to HiFi systems does not play any role.
Here we are in complete agreement!!
As to the "French" studies, were they controlled or just casual observations?
I wouldn't call them casual, but definitely not scientific.
That said, many people dispute the scientific findings of Toole, Olive and others.
I don't, but I think personal preferences - wrt both the audio reproduction system and the room, are not to be neglected.
Axisymmetrical horns that don't beam too much, are definitely what I'm after.
That said, many people dispute the scientific findings of Toole, Olive and others.
I don't, but I think personal preferences - wrt both the audio reproduction system and the room, are not to be neglected.
Axisymmetrical horns that don't beam too much, are definitely what I'm after.