I agree it is fairly conventional. More sensible even than Camps original scheme. But I still define it as a lot of eq to get a desirable result. A +6 and a -9 filter is close enough to my affore mentioned 20db eq range for me, personally, to call it a lot of eq.
It simply, usually, takes a lot of eq to flatten a sub in a room. Normal situation. Camplo calls it a little eq is what struck me as, Camplic...
You are looking at the range over where the EQ is happening to determine the amount and camplo is considering the number of PEQ filters he needs to use to describe a little or a lot of EQ, both reasonable if you understand the context.
The argument is a little deeper than this idea of hearing one source.....This one source can grow in size....that aspect is discernable with eyes closed.....Take two woofers play one then immediately play both at equal spl to listener.....the source will be wider to the listener in the same direction the two woofers stretch the radiation size, while still sounding as a single unit.....yet a larger, single unit. Still, everything I just explained makes no sense without context to listening proximity lol. The experience will change whether 2ft or 20ft.
This same affect happens in the crossband. The energy being expressed moves in the direction the signal goes on the baffle, at least to some extent.... Only at far listening distances can you cheat this unless the drivers are really small which allows the tight physical summation.
I think my current scenario is doing very good considering how big it is, how far apart the drivers are, no DSP help outside of some, little, eqing.....
I am still designing with the mindset of listening within 1m. all the aspects are, very intimate to the listener, with close proximity.
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You make some great points. The directivity has to match at xo. Leading people to large woofers that will beam a bit. Taking the horn down close to cut-off helps in this regard, as directivity is starting to dissappear on the horn right when it transitions to a woofer with almost no directivity (in my case 500hz from a 12 inch). One question, how on earth to you get the directivity of a horn operating a bit above cutoff (where it still has pattern control), to match the directivity of a small mid driver?
Yes Mark, well said, even though I may discount the subjective part a bit.
To me there is only one reason to take the Xover lower from a waveguide and that is to match it to the woofer DI at the Xover. But unless you have a low DI waveguide or a very large woofer, this is never going to be below 500 Hz. I think that you would agree with this, but you did not specifically say it.
I did many paper designs of a high DI system with a 90 degree coverage that had a low Xover of about 500 Hz, (the idea was to get a high DI lower in frequyency) but it required an 18" direct radiating and a 22" waveguide to match. It looked good on paper, but was not economical at that point.
To me there is only one reason to take the Xover lower from a waveguide and that is to match it to the woofer DI at the Xover. But unless you have a low DI waveguide or a very large woofer, this is never going to be below 500 Hz. I think that you would agree with this, but you did not specifically say it.
I did many paper designs of a high DI system with a 90 degree coverage that had a low Xover of about 500 Hz, (the idea was to get a high DI lower in frequyency) but it required an 18" direct radiating and a 22" waveguide to match. It looked good on paper, but was not economical at that point.
Thanks cspieker, and thanks Earl,
MEH's.
I've used the same sized horn and pattern, with the CD crossing straight to various sized mid-woofers from 8" to 12". With xover frequencies ranging from 480Hz to 700Hz. These all sounded pretty much the same, all crossed to a sub at 100-120Hz.
Then last July, i added in four 4" mid drivers, which work fine on same conical horn anywhere from 250Hz to 1100Hz. It's easy to cross to the CD anywhere between 450Hz and 1100Hz. I've kinda settled in at 900Hz, which is certainly clearer than anything below 700Hz.
And yeah, I discount my own subjectivity... heavily ! Certainly expect others to do so too
Up until last July, i thought i had achieved sound about as good as i had heard anywhere. Then i was like WTF, listen to what the small mids have added, and raising the CD xover
If i still didn't have that opinion 6 months later, i wouldn't be subjecting folks to my impressions. But ...subjective it is... I haven't found any measurement that can distinguish between different xover points at all, including polars.
MEH's.
I've used the same sized horn and pattern, with the CD crossing straight to various sized mid-woofers from 8" to 12". With xover frequencies ranging from 480Hz to 700Hz. These all sounded pretty much the same, all crossed to a sub at 100-120Hz.
Then last July, i added in four 4" mid drivers, which work fine on same conical horn anywhere from 250Hz to 1100Hz. It's easy to cross to the CD anywhere between 450Hz and 1100Hz. I've kinda settled in at 900Hz, which is certainly clearer than anything below 700Hz.
And yeah, I discount my own subjectivity... heavily ! Certainly expect others to do so too
Up until last July, i thought i had achieved sound about as good as i had heard anywhere. Then i was like WTF, listen to what the small mids have added, and raising the CD xover
If i still didn't have that opinion 6 months later, i wouldn't be subjecting folks to my impressions. But ...subjective it is... I haven't found any measurement that can distinguish between different xover points at all, including polars.
Seriously? Do you mean out of the limited sample size that you ran, or in general? Because I can point to dozens of examples on my website. The crossover point is clearly seen in the DI among other things. I'll give you that sometimes it's so bad that the exact frequency is hard to pinpoint but make no mistake it's obvious to find the range in which it lies.
If I recall correctly, we came, or I came, to the conclusion that the biggest horn you had was capable of a 600hz xo 🤔🤔🤔
I don't think that you understand the problem to think that any reasonable waveguide is going to be the answer. Your mids will have a DI of close to 0 dB throughout their bandwidth. What waveguide is going to go smoothly to DI = 0 dB?
Concerning DI - What relationship does a MEH and it's respective drivers and crossover points have to do with a waveguide/horn and separate direct radiator? It seems like an apples/oranges discussion.Thanks cspieker, and thanks Earl,
MEH's.
I've used the same sized horn and pattern, with the CD crossing straight to various sized mid-woofers from 8" to 12". With xover frequencies ranging from 480Hz to 700Hz. These all sounded pretty much the same, all crossed to a sub at 100-120Hz.
Then last July, i added in four 4" mid drivers, which work fine on same conical horn anywhere from 250Hz to 1100Hz. It's easy to cross to the CD anywhere between 450Hz and 1100Hz. I've kinda settled in at 900Hz, which is certainly clearer than anything below 700Hz.
And yeah, I discount my own subjectivity... heavily ! Certainly expect others to do so too
Up until last July, i thought i had achieved sound about as good as i had heard anywhere. Then i was like WTF, listen to what the small mids have added, and raising the CD xover
If i still didn't have that opinion 6 months later, i wouldn't be subjecting folks to my impressions. But ...subjective it is... I haven't found any measurement that can distinguish between different xover points at all, including polars.
Thank you. It seemed like this discussion was starting to go down a rabbit hole, never to return.
I doubt we are even talking about the same thing in the same language.
Then all this thrashing around at least got you somewhere you like
Don't discount it too heavily, I don'tAnd yeah, I discount my own subjectivity... heavily ! Certainly expect others to do so too
Earl having read all of Mark's thread's on his builds I am certain he means within his own speakers he cannot find a measurement that explains his preference.
Yes I am happy so far. As I said, with the size of the system....listening at such a close proximity, the cracks are exposed...but as for making the best out of it...I think PPSL is the best I could do to get desired output into a package that would fit nicely under the midrange.
Right now I wonder how will this nuance affect how I decide to EQ....I've always wondered this actually. Yeah proper listening distance is the easy answer....but how to get such direct energy and headroom and bandwidth, into a package that sums as good as I am striving for
Its no wonder that so many people have landed at a large MTM. It seems to me that the Largest MTM you can make is a good route....I do have the drivers....but I am just talking.If one were to create a large MTM with side firing subs, I think this is a good idea, even at the sacrifice of losing some sensitivity from the side mounted woofers. Maybe a Large Floor standing MTM with an Array of woofers down the side from top to bottom.