D-MAN Posted October 20, 2006 Share Posted October 20, 2006 That is something! That notch in the 30's is probably due to the horn reactance at Fc (38hz), but look at that spike below it where it should be falling off rapidly instead. Add more. see what happens. DM Quote Link to comment Share on other sites More sharing options...
bodcaw boy Posted October 20, 2006 Share Posted October 20, 2006 Weren't the stock Jubilees you heard heavily EQ'd? DM nope. Quote Link to comment Share on other sites More sharing options...
jwc Posted October 20, 2006 Author Share Posted October 20, 2006 I have a Jubilee. I'm not gonna post every detail since I took about 2 hours to figure out the deal. Anyway. Dana. there wasn't much room left in there. I changed out to Pioneer drivers. Noticed right off the bat on RTA that I was now getting signals of decent dB in the 40Hz range. However, still had drops in the 70's and just over 100. You know what, I repositioned the Jub more in the corner and slightly moved the mic around. Now that 70's and 100's stuff is mostly gone. I still now have 40Hz stuff. Quote Link to comment Share on other sites More sharing options...
jwc Posted October 20, 2006 Author Share Posted October 20, 2006 ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, Quote Link to comment Share on other sites More sharing options...
jwc Posted October 20, 2006 Author Share Posted October 20, 2006 ,,,,,,,,,,,,,,, Quote Link to comment Share on other sites More sharing options...
jwc Posted October 20, 2006 Author Share Posted October 20, 2006 Now they compete with the dbb. About the same as far as low signals and punch now. The Pioneers are slighly less sensitive than the kappas were. I had to attenuate the 902 a little more. The dbb's will shine a little more with stuff like bass guitar but the kick drum stuff is exceptional on the jub. And guess what...I got a little of the boom! Sounds good. Listen some more tomorrow. Terry....I can now debate that "trade off" now. More tomorrow. Quote Link to comment Share on other sites More sharing options...
Coytee Posted October 21, 2006 Share Posted October 21, 2006 Congrats!! Boom is good!! [] Quote Link to comment Share on other sites More sharing options...
Deang Posted October 21, 2006 Share Posted October 21, 2006 Is the chamber still stuffed JC? Those plots look a hell of lot better. Quote Link to comment Share on other sites More sharing options...
jwc Posted October 21, 2006 Author Share Posted October 21, 2006 No stuffing. Empty stomach. The Pioneer drivers sound different than the Kappas. The Kappas are very fast and don't go quite as low. When the kappas were in there, I stuffed with a large pillow that was housed in a plastic shell. I would not have been able to squeeze another one in there. Now the Pioneers are what I was looking for. There is a slight "crudeness" or boom. The real Jubilee is like that IMO. The only difference I see with mine and the real one is the total SPL. Now I realize that my dbb's are some real SPL machines but they aren't horn loaded. The pioneer drivers have a low SPL rating to start with. I was playing the one Jub today and the meters on my MAC MC252 were reading up to 25 watts. I've never seen that before. The dbb's would get way loud before I could get to that point. Now....when I have the one jub at 25 watts, the bass really started coming through. My AH! CD Player skipped on some RAP MUSIC and the player is about 25 feet across the room from the jub. Never done that before either. Now I was playing lots of different music for comparison purposes. I still say that are times where the dbb will shine and that is with bass guitar sounds and synthesized bass. It doesn't throw out that bass drum like the jub. That sound is what everyone gets all fired up when Roy plays "Hotel California" in the listening room at Hope. Apparently, that sound was played two years in a row. Probably because that bass drum kick that surprises you with the live version of the song. Good gosh...did you see how far out this bass horn will go. Easily over 1000Hz with the Pioneers. When people first started posting about the Jub, it was stated that it can go on a long wall as opposed to have to be in a corner. I wonder about that as the snug corner placemnet did it in my room. Richard....I know you moved yours slightly out of the corner and turned them. I forgot, was that for cosmetic reasons or you liked the sound better? It is interesting how this network works well with this setup. However, I have the 902 attenuated -9 dB! unlike the dbb's it was attenuated -7.2 dB. When the K55's were in the dbb, I think they were attenuated -6.8 dB. For now...I am pleased. Quote Link to comment Share on other sites More sharing options...
jwc Posted October 21, 2006 Author Share Posted October 21, 2006 I forgot to post this. The last 3 images in this thread are the raw bass bin with the pioneers. I meant to give the expanded view up to 200Hz. Here it is. Does it look like it rolls off in the right place? Does to me. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted October 21, 2006 Share Posted October 21, 2006 Good gosh...did you see how far out this bass horn will go. Easily over 1000Hz with the Pioneers. Think you need ot send your mod's to the patent office. Quote Link to comment Share on other sites More sharing options...
DrWho Posted October 21, 2006 Share Posted October 21, 2006 So when you gonna start playing with porting and all that? [] Also, what's up with the jagged response up high? Is that the result of your "skipping" tones? Was your mic on the floor for the measurements? And do you have a comparison graph against your dbb's? I find your impressions about hornloaded versus direct-radiating bass to be very in synch with my impressions. Drums are unreal because of the improved dynamic tracking, but bass guitars (especially when more electronics are involved) don't have that same grunge to them. Quote Link to comment Share on other sites More sharing options...
Coytee Posted October 21, 2006 Share Posted October 21, 2006 Richard....I know you moved yours slightly out of the corner and turned them. I forgot, was that for cosmetic reasons or you liked the sound better? I toed them out more for widening the sweetspot (that I can't sit within [:@]) rather than anything to do with the bass response. Here's something I've been meaning to email BerryBoy and ask... "since the Jubilee was TESTED in the middle of the chamber, as contrasted with in the corner, is it fair then to conclude that the Jubilee does NOT NEED to have any corner placement"?? Recall the pic I once posted with the Jubilee in the chamber? It was no where near the revolving door. Seems to me if it was "supposed" to be in a corner, they would have measured it from there. As it is, it seems to me, it's been measured for more of a freestanding location. That told me toeing in/out won't matter (and I feel it doesn't given my ears). I DO think however, it allows the spot from where you were listening to become the sweet spot instead of the table that was in front of you (had I not turned them outward). Quote Link to comment Share on other sites More sharing options...
Coytee Posted October 21, 2006 Share Posted October 21, 2006 Wouldn't they test it in a corner if it was to be optimized for a corner? Quote Link to comment Share on other sites More sharing options...
DrWho Posted October 21, 2006 Share Posted October 21, 2006 They do that because they want to get an idea for the free-field response of the speaker. Any of the associated room gains and all that can then be easily predicted from this information (instead of having to subtract and then add back). I remember Roy mentioning that the frequency response of the Jubilee smooths out when loaded in the corner (it makes the horn seem longer) and you're going to get the associated corner-loading gains in the bass response. In a movie theater setting they're looking at half/quarter space scenarios and thus won't have as much reinforcement - meaning the way they're voiced means they will sound fine in both applications. And at the wavelengths in question, a few inches here and there shouldn't make a significant difference - in terms of boundary gain. That's not to say that a few inches can't make a significant difference with the modal response of the room. JC, you might find this program interesting as well: http://www.hometheatershack.com/roomeq (it seems his server is down at the moment though...email me if you'd like me to send it to you). It's a fancier RTA program that happens to be free and will provide better resolution than your current RTA program. Quote Link to comment Share on other sites More sharing options...
Coytee Posted October 21, 2006 Share Posted October 21, 2006 Gotcha Doc!! Learn something new every day. Seems today's lesson is over now. [] Quote Link to comment Share on other sites More sharing options...
jwc Posted October 21, 2006 Author Share Posted October 21, 2006 Richard....I'm not the expert. Whatever way you had them at your house...sounds good. When you get them in a bigger room...the direction thing may not be as important. Mike B. Yes I skipped tones to speed things up. Ignore the in between short spikes. The thing is Kinda Flat way out past 1000Hz. Better than I expected. PORTED VERSON! I can do it. Thought by now you guys might be getting bored with this. I felt bad last night after all those plots I posted. I felt for a minute like I was a "hey look at me". I noticed for the first time that my name was in the "most users list". It felt a little weird. I'm gonna take a break from moving things around as my back hurts a little. I may just sit and listen tonight and try and draw out ported options. I had before about three diferent ways to do the baffle. I can do it if you guys stick with me. I wouldn't want to start it and then no one starts to chip in anymore. I bet the driver situation would change with the 12" drone in there. I feel like this was a success so far. It even sounds better today. Makes me think the woofers my need to break in. Quote Link to comment Share on other sites More sharing options...
gaspr Posted October 21, 2006 Share Posted October 21, 2006 Congrats JW. Those plots are looking really good. You should be very proud of yourself. I have enjoyed following along with your progress. Don't stop now!! Quote Link to comment Share on other sites More sharing options...
jwc Posted October 21, 2006 Author Share Posted October 21, 2006 For starters, who thinks the total throat should stay 90 in sq. Right now, the throat for each 12" driver is 45 sq in (slot 5 x 9 inches). Now, can I assume the drone will will also have a throat. So should I make the active drivers slot 5 inches wide by 6 inches and then a slot for the drone 5 x 6 inches. Each being 30 sq inches a piece (x 3 = 90 sq in). With this approach......the pioneers may not be a favorable option as they like a bigger throat. The kappas like a smaller throat from a calculation standpoint. The other way to do it is leave the throat for the two active drivers the same at 45 sq inches and make the slot opening for the drone horizontal with a wide splitter that is 9 iches wide or 10 inches wide. Then the height of the slot could be short like 3-4 inches. There would be no "ramps" coming from this slot but rather horizontal parallel panels that are are only a 3-4 inches from each other. Therefore the ramps/flaring of the active drivers won't change much from the way they are now. I'll see if I draw what I'm talking about with this second option. gaspr, thanks for the compliment Quote Link to comment Share on other sites More sharing options...
jwc Posted October 21, 2006 Author Share Posted October 21, 2006 Now, we have seen the way drawn out with the 2 drivers and drone in the middle all with equal apearing slot and ramps. But what of the below. Imagine that horizontal slot with a wide splitter and the slot around 8-10 inches wide and maybe 3-5 inches tall. Now you can see the flare from the active drivers didn't change much and only about 3-5 inches of the total height of the horn was taken away from them. Sure, the initial flare on the real Jubilee and mine is "to fast" and sure we could afford for the flare to be "slower" here. Now this shouldn't change the total throat size as much either. Still keep each active drivers throat at 45 sq in. Quote Link to comment Share on other sites More sharing options...
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