You mean the resonant of the horn or the diaphragm? So far I've gathered that only the vent tuning is considered...not the driver FS.....as well, it still ultimately comes down to excursion vs desired SPL...with a twist, XO choices
With a 150hz horn I can legitimately cross at 300hz or maybe a little bit lower.
Hmm, if tuning based on a CD's Fc, then a 1" TAD TD2001 would be limited to a full size ~ 340 Hz compression horn IIRC and the 1" 800 series Altec could only do ~ 680-700 Hz, so guess that's why some folks don't like them on 500 Hz horns, but it doesn't work that way.
Build the horn big/long enough and they can be driven much lower, though at the cost of efficiency of course since we're always trading efficiency for BW.
Build the horn big/long enough and they can be driven much lower, though at the cost of efficiency of course since we're always trading efficiency for BW.
I mean the diaphragm. Again, I'm using abbreviations and not being clear.
My emphasis is on "so far" - "Also, so far, it doesn’t make sense to me to use a CD down to its first resonance".
I may be writing beyond my current open window. GM may have explained it for me in post 7862 after yours.
When you say 'vent tuning', do you mean a vent in the Compression Driver; CD? I notice there is a vent, hole with screen, in the back side of the Radian 951 compression drivers that I have; A screened hole between the cooling fins. I don't see this in the other 2 different compression drivers that I have.
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AFAIK some French folks have used the TD2001 from about 500 Hz with JMLC horns, including Jean-Michel himself.
Legis uses the HF108 with his A-290 + throat adapter.
This is what loading from a 38 cm deep horn (excluding adapter) looks like:
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Vented design is any cabinet with a hole in it, in particular the part with the hole...venting pressure waves to the outside...it's tuning to me is the loudest resonate note, fb is when its where loading starts to fail. If it represents a normalized -3 or -6db, Idk....
F can be seen in the Fr....tell me you're F without telling me....mechanical efficiency goes down, excursion goes up vs resulting SPL, very quickly as get lower of the resonate note....its just a another topic governed by excursion vs desired spl...if you are playing at F, with just 1-2mm of excursion your issues are elsewhere than thd.
Where did I say/imply this?!
We're trading a high efficiency over 'X' BW to a lower efficiency over a wider BW, so yes in your words in that a narrow cup with 'x' fill line will drop/'spread out' to a lower, wider 'y' fill line.
Clear now? BTW what's your native tongue?
It's the HF108 (non-R).
Legis is pleased enough with the HF108s that he has decided to sell the HF1440s.
Since he uses his Colossi in 2-way configuration, they should be highlighted in this thread.
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If you read the thread you'll find that it's a well thought out (and executed) concept.
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Thanks for your thoughtful response. No blood no foul. I appreciate all your comments.
I'm taking an approach that I think will get the results I'm looking for: Equal 7-channel sound field-equal voicing is important to me, otherwise the equal surrounds are overkill; quality at a price I'm willing to bear; 2-way simplicity-if this 7-channel bi-amped 2-way system could be called simple; a system that will still reasonably fit in the space I have. If I was concentrating on 2 speaker stereo, I would probably build a 3-way, and add a high quality Mid, like the AETD15M, between the AETD15S woofer and Radian951/Horn combo.
It's just a personal choice. As your quote from Greg Timbers said - "There is no silver bullet". I quit looking for absolute accuracy. It's a holy grail with physics in the way. Perhaps I will later change to Truextent Be diaphragms in the Radian951's used just for LCR, since the cost is high; as long as I can preserve the equal sound field. Radian says they are researching the use of carbon fiber diaphragms too. By that time, I may have the system completely tweaked. Perhaps I will try a better horn/waveguide. It is a hobby too
Docali's contributions are of great interest to me. And, I like his approach. We are blessed with people like him in this field.
I bought a good book - High Quality Horn Loudspeaker Systems, by Bjørn Kolbrek and Thomas Dunker:
Bjorn Kolbrek talking about the book "High Quality Horn Loudspeaker Systems" - YouTube
Home
Let's see how much of it sticks.
I think it is comforting knowing that most of what we try accomplish is via technique and approach and not so much which special driver we use. Not to say that a certain level of driver quality isn't desirable....but to say, that we are looking grab a final 10-15% performance after the physics have been sorted out. You might even say that the last parts of our endeavor towards absolute accuracy really is more like absolute catering to out personal desires vs whats possible...because physics is in the way (at present) and we are trading one distortion away to gain another somewhere else. The comfort is knowing we are able to achieve high levels of accuracy, even if not absolute accuracy....still, absolutely satisfying when all said and done, and available to the common man....made possible by the not so common men, who are pioneers to the culture, yet share their knowledge and wisdom freely.
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Say what? I find this to be a very interesting statement. I wonder if it has to do with a theory of mine that relates to the idea that midrange is the most important part of spectrum vs how my system is projected to be configurated...at first my mind said that by removing excursion from the midrange via 2.5way, allows for good mechanical efficiency and less issues of midrange excursion and TMM XO issues.Yes 2-way. Tried the 2,5-way 2nd time during the summer. Same outcome, it's also good but subjectively not as good as 2-way.
Later I was brainstorming configuration and focusing on the thought of midrange taking first priority, my thoughts were that more Sd should be focused on midrange than anything else. There seems to be a tolerance for treble and bass distortion on some level but midrange is the most crucial to remove all distortion.
So in regards to the Shadow of the Colossus, the designer says he preferred 2 way vs 2.5....in which hes adequately set up to do either. He has enough sd to keep excursion very low in either setup (4 - 12"'s and 4 - 15"s per side I think?). It would seem that he has plenty enough SD with the 12"s that the additional help from the added 15's in that part of the spectrum not covered when in 2.5way mode, would go un noticed or a disadvantage being yet another set of redundant source? This makes me look to directivity advantages which is basically saying he's increasing the reach of the direct field, and at distance this is going to increase SQ. Up close like I intend to listen, not so much, you would think. Maybe I should change my stance on HETMM2.5way, to being the best config for close proximity listening, where as, the far away (I would say far field but Dr. Geddes doesn't like it lol, far/nearfield is a relative term), listening position, direct energy is not so abundant and all hands on deck is the approach. The Shadow of the Colossus might be considered a large "minimal driver 2 way line array" of sorts, no?
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Amen. Reproduction is best when it pursues and captures the art. The art will always be interpreted through lenses with some color; hopefully as little color as possible without becoming too dogmatic in approach. The devil is in the psychoacoustic details.
Talking about art – Please take this in as light hearted, well meaning, and fun poking a way as possible – I hope you are getting better sleep. Communicating with you lately has been like talking with a Jackson Pollock painting.
Perhaps it is one Jackson Pollock painting talking with another. My sleep patterns are disrupted around the equinox in March and September.