.....
For me it looks like all SS charts are wobbly below 100Hz be it Discovery, Revelator, or Illuminator except that lonely 32W/4878T00, so maybe it has been measured more carefully in more bass friendly environment because its their top model. For example look the wobbly signs in SS datasheets for 10F/8824 plus 26W/4558T00, and then see it isn't replicated in Klang & Ton or Voice Coil measurements here http://www.scan-speak.dk/datasheet/reviews/10F-8424G00-KlangTon2010-2.pdf, http://www.scan-speak.dk/datasheet/reviews/D2604-833000_26W-4558T00-VoiceCoil_2011-2.pdf.
ooh and Happy new year : )
I can agree with that point of view, because outside measurements of the 30W do look better. It's just that 32W graph that was different. Though the 30W isn't too far behind in actual measurements by 3rd parties, same goes for the XXLS.
I think you can guess what I'm looking for. As the Vifa TC9 is kind of the cheap sibling of the 10F (to me in my application), I'm looking for a cheap 32W and wonder if the XXLS and/or the 30W deserve that title.
Ronald,
Why the insistence on a very low moving mass for a sub woofer? If you aren't as I suppose trying to go up in frequency response from a sub why worry about the mms which is typically increased to decrease Fs? As we lower the mms we have to also change the spider and the surround to match the very low mass cone, this is what I have done in my much smaller drivers, but they are intended to be very wide band devices and not used only for the low frequencies. It does become more critical the choice of spider or double spider to keep the Vc centered in the gap, and a double spider makes it even more difficult to match the low mass cone. Just some questions for the New Year to think about. Why not look at efficiency rather than mms since you are only looking to reinforce the very lowest frequencies?
Why the insistence on a very low moving mass for a sub woofer? If you aren't as I suppose trying to go up in frequency response from a sub why worry about the mms which is typically increased to decrease Fs? As we lower the mms we have to also change the spider and the surround to match the very low mass cone, this is what I have done in my much smaller drivers, but they are intended to be very wide band devices and not used only for the low frequencies. It does become more critical the choice of spider or double spider to keep the Vc centered in the gap, and a double spider makes it even more difficult to match the low mass cone. Just some questions for the New Year to think about. Why not look at efficiency rather than mms since you are only looking to reinforce the very lowest frequencies?
Price range of most SS 30W are around € 225.00, cheapest found at € 207,10.
Price range of XXLS is around € 250,00/260,00, cheapest found at € 221,30.
As I am in Europe and subs are big and heavy, I'll have to keep it somewhat local.
Because I'm (planning to) using them up higher than most people think. They will play alongside the arrays in a timely manor to make up for room positions. Therefore I want them to be clean there so I can integrate it easier. A clean sub can do more than that first octave alone.
All of the lowest mass cones I found have other problems, but I'd like to keep all options open on how I can use them. Think Beolab 90 in a crude way
.Might not even be that crude once I'm finished with it. That is if I can get lucky with placement options.
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Meaning they would cost about the same over here as the 30W/XXLS.
I found some very convincing data on the 30W in several places. Not seen comparable plots yet from the Dayton, the Dayton Audio RSS315HF-4 12" Reference HF Subwoofer is the one that caught my eye. If I could shop at US prices I'd buy one immediately, just to try the theory.
Don't want to sound like I disapprove of them, all I did see were a lot of favourable comments. In a separate HT room I'd add 4 or likely even more and be done with it.
It turns out that two is almost as good as four, and more than four is a waste of resources. Check out this presentation:
https://www.harman.com/sites/default/files/white-paper/12/11/2015 - 06:12/files/multsubs.pdf
I made some measurements but this presentation got me thinking. I was previously using custom EQ for each sub, but Mr. Welti suggests using the same signal for both subs. I tried putting my subs on opposite wall midpoints and I'm getting a reasonably even response across the couch. Sounds pretty good even without EQ, just level and delay adjustment to get proper summing around 80 Hz. Doing some more testing now, will post responses soon.
This is another presentation that is pretty useful, but you've probably seen it before:
www.gedlee.com/downloads/OptimalBassPlaybackinSmallRooms.pptx
It talks about why level is the only thing that matters in the sub bass.
https://www.harman.com/sites/default/files/white-paper/12/11/2015 - 06:12/files/multsubs.pdf
I made some measurements but this presentation got me thinking. I was previously using custom EQ for each sub, but Mr. Welti suggests using the same signal for both subs. I tried putting my subs on opposite wall midpoints and I'm getting a reasonably even response across the couch. Sounds pretty good even without EQ, just level and delay adjustment to get proper summing around 80 Hz. Doing some more testing now, will post responses soon.
This is another presentation that is pretty useful, but you've probably seen it before:
www.gedlee.com/downloads/OptimalBassPlaybackinSmallRooms.pptx
It talks about why level is the only thing that matters in the sub bass.
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Happy New year all!
Wesayso, been doing some research for you....
What about a pair of these:
TIW 300 - 8 Ohm
MMS 92g
BL 16.5
Nice FR.....
Wesayso, been doing some research for you....
What about a pair of these:
TIW 300 - 8 Ohm
MMS 92g
BL 16.5
Nice FR.....
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I'm sure everyone reading this thread will probably have noticed I can be pretty pig-headed/stubborn. Yeah, I've read both. And I'm not going to dispute it, at least, not completely.
Way before I ever started building my arrays I've read about all I could find by Geddes, and stumbled over the JBL research as well. But I also stumbled over a lot of other things in those long nights. On more than one occasion I saw discussions about "You are here" and "They are there" kinds of sounds. Especially between Pano and Geddes. That stuff keeps resonating in my head. Making me wonder so to speak. This, together with Dunlavy's words and a lot of other little things made me decide to do my own little experiments to find my own truth.
Same goes for the early reflections Toole referenced opposed to Dr. Geddes views on this. This stuff I had to try for myself to form my own opinion.
That makes me do things my way, search for "my own truth".
Some things like people quoting Geddes views on distortion and it's influence on the whole package also didn't 'ring' right with me. Having read most if not all of Geddes posts the thing that I got from it is distortion shouldn't be a problem. If you use functional CD drivers and the right horns. He wasn't dismissing distortion as I read it, it just had to be down far enough not to be/impose a problem.
As Geddes isn't a firm believer in the "you are there" sound as a possibility (at least that's what I got from his posts) I cannot stop to think why. I believe the devil is in the details. All of them are important in a certain way. Why not find out for yourself what works and what does not. So that made me put in special effort on the timing, especially on that bottom end.
I'm sure I made mistakes and will again, how else am I going to learn. Finding my own truth has been my motivator throughout this entire journey. Revisiting every concept I try at least more than once.
So no matter what Geddes thinks matters in the bottom end, I feel different about it, the timing part being that essential difference. Sure it's not easy in a living room, but I think I have shown it's not impossible.
So whatever I do end up with, it will be filled with several experiments to find my own truth. Though I will be going in knowing the theories that were written. By all camps I ever took an interest in.
You're preaching to a guy who uses passive components in an all active setup. Pretty much everybody told me that wouldn't be needed. Guess what, I still have the compensation for the big impedance peak in place. How many really use drivers trough that impedance peak. Using both sides of that peak in their listening experience. Dumb? Maybe, Stubborn? I sure am.
So far this journey, basically looking for my own version of the truth, has taught me valuable lessons. I'm sure I can learn some more. Am I right? I hope I am, something sure is working here in my room. It was already more than worth it to have felt so much emotions building, setting them up and listening to these speakers. I'm ready for more lessons just like that.