The Dude Posted January 12, 2016 Share Posted January 12, 2016 Here is my Jamboree on the other side. I need to zoom in, but from I can tell it looks pretty close. Quote Link to comment Share on other sites More sharing options...
jwc Posted January 12, 2016 Share Posted January 12, 2016 Awesome. Can u change the vertical axis to about a 50 dB range and the FR range 1k? looks like the drop under 120hz to 40hz about 13dB. Great work and data 2 Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 12, 2016 Share Posted January 12, 2016 Awesome. Can u change the vertical axis to about a 50 dB range and the FR range 1k? looks like the drop under 120hz to 40hz about 13dB. Great work and data Probably won't be for a couple of days, but yeah no problem. Quote Link to comment Share on other sites More sharing options...
jwc Posted January 12, 2016 Share Posted January 12, 2016 Yes. Another making double will kick up the left end of the curve some. Is this up against a wall? If half space.....away from back wall or corner....then look at why there is a drop under 120hz. This looks very typical. Quote Link to comment Share on other sites More sharing options...
jwc Posted January 12, 2016 Share Posted January 12, 2016 (edited) So what is the physical mouth here? 9 x 19 x 2? 342 sq in? measured in half space sound like to me. maybe a little more like 1/3 space ...close to a wall maybe. Think of the 223Hz tractrix horn folks build. Fc 223Hz in full space. Mouth is 24 x 12 = 288sq in. Ok...then what if we made that horn with Fc ~120Hz full space...then we need about 576 sq in mouth. you say hmm..... My single jamb mouth is 342sq in and I'm solid horn efficiency to 120Hz. How did that happen? That's where room boundaries come in play. You are half space or better so you need less mouth to get lower frequencies. You can stick a mouth horn 342sq in corner all day....and that isn't near big enough to get good efficiency at 40Hz. Not I'm obviously leaving horn length out of this for simplicity...as that has something to do with it. Think of Bill Fitzmaurice Titan 48 sub. This horn sounds goo but has a serious drop under 120Hz down. The horn is pretty long in length but has a little mouth. Its been truncated. He is relying on you to lay the cabs on the ground (1/2 space) and line up the mouths to bring up that bad dogleg. It works though. I love threads like this. You can get addicted to it and then make yourself take the measurements outside. Then you really know what u did. This response look typical. looks good. If you are able...shink the values of the x and y axis. It will make sense. Edited January 12, 2016 by jwc 1 Quote Link to comment Share on other sites More sharing options...
Zoef Posted January 12, 2016 Share Posted January 12, 2016 (edited) Never been good at reading graphs. When i think something looks good it is sounding bad. And if it sounds good....well you get it. I never heard a jamboree/jubilee (or khorn.....) so my reference is a la scala. Would you say it has got more low end then a la scala? If so, for me you have great succes. Edited January 12, 2016 by Zoef Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 12, 2016 Share Posted January 12, 2016 If half space. This may not pertain to my situation, but. I had to look up what half space was. I have heard you and others talk about it before ( Half space, quarter space, etc..). What I don't understand about half space, is do they consider 2 or 3 walls or just 1. If it was in a corner, it would have three boundaries, two walls and the floor. Does this make it quarter space or still just half space? Yes, I have it pulled 11" from the back wall. Mainly do to the horn being to deep, plus once built there will be another Spud clone back there. Could the Spud clone on the left side be acting as a boundary creating more boost in the lower frequency? Quote Link to comment Share on other sites More sharing options...
Zoef Posted January 12, 2016 Share Posted January 12, 2016 (edited) I've got to say I am not that impressed. However there are a few things to take into consideration. I have some tweaking to do and would like to swap sides with the Jamboree. I also have to remember that this is half the size, so what does that make the bass output down 3 db? On Dana's website he states 4dB less...... Edited January 12, 2016 by Zoef Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 12, 2016 Share Posted January 12, 2016 Maybe this maybe a little more like 1/3 space ...close to a wall maybe. Answers this, I had to look up what half space was. I have heard you and others talk about it before ( Half space, quarter space, etc..). What I don't understand about half space, is do they consider 2 or 3 walls or just 1. If it was in a corner, it would have three boundaries, two walls and the floor. Does this make it quarter space or still just half space? No boundries = full space floor = half space floor+one wall = 1/4 space floor+two walls = 3/4 space or 1/3 space? I think I have something to play with tonight, I will report back. You can get addicted to it and then make yourself take the measurements outside Planning a more warm day. Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 13, 2016 Share Posted January 13, 2016 Playing around with REW, as i just got it installed on my laptop with Linux. So I had to take some new measurements. I thought to answer Zoef's question I took a measurement at the same height as each 49" back. Same height is right above the Jamborette but slightly lower than the top of the Lascala. Jamborette in red, Lascala in Purple Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 13, 2016 Share Posted January 13, 2016 Awesome. Can u change the vertical axis to about a 50 dB range and the FR range 1k? looks like the drop under 120hz to 40hz about 13dB. Great work and data If this is what you wanted to see, than I think I am about 23db down from 120 to 40. Quote Link to comment Share on other sites More sharing options...
jwc Posted January 13, 2016 Share Posted January 13, 2016 Ok so I'm gonna go out on a limb and take a quick guess that..... 320Hz very well could be your room cancelations. Horns is pretty flat to 110-120Hz. Yep big drop off down to 40Hz No boundries = full space floor = half space floor+one wall = 1/4 space floor+two walls = 3/4 space or 1/3 space - well...more than one answer here. Like on a floor but away from one wall. For the small mouth of this horn....I like it. La scala has such a rapid flare. Looses the long wavelengths. Could never do 40Hz w/o distortion with EQ. Jamborette could EQ to 40 with less distortion I bet. jc 1 Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 13, 2016 Share Posted January 13, 2016 My thought for the morning. I have 2 other drivers I will test this weekend, K-33 c or b (I don't recall which one), and Crites cast frame. I have two driver mount boards, the one I am using has the 6x13 opening. I have a 3x13 opening, that I will try with this driver along with the the other two. All in all (here's that thought I mentioned earlier), this is a decent low cost build that could be used in place of a Lascala. However if I came across a pair of Lascala bass bins like the one I have. Then I would just use those. Then again if you were to build, maybe it would be just as easy to build a pair of Lascalas. Which ever, I all ready have one Jamborette and making two more for my L/C/R is in the works. Which if all goes well will only cost me about $30.00 some gas money and about 1/3rd of my time to actually building one (more on that later). Quote Link to comment Share on other sites More sharing options...
Zoef Posted January 13, 2016 Share Posted January 13, 2016 Playing around with REW, as i just got it installed on my laptop with Linux. So I had to take some new measurements. I thought to answer Zoef's question I took a measurement at the same height as each 49" back. Same height is right above the Jamborette but slightly lower than the top of the Lascala. Jamborette in red, Lascala in Purple Thanks! Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 16, 2016 Share Posted January 16, 2016 On a couple of songs I was hearing some scuffing. I remember having this issue with 15c, I think when I spoke to Claude he recommended adding additional gasket with the driver or just turn it down. I don't have any so I swapped out the driver with a K33b, so far sounds good and no scuffing. REW all of sudden doesn't have any output. So now I have to figure out whats wrong before I can run a test to see how it performs in room. Quote Link to comment Share on other sites More sharing options...
Zoef Posted January 16, 2016 Share Posted January 16, 2016 Could this be because the 15c has a very low xmax? (2.4mm) Quote Link to comment Share on other sites More sharing options...
jwc Posted January 16, 2016 Share Posted January 16, 2016 Was this w/o EQ? Of note, One time I mistaked the sound of "scuffing" as you say with the startling sound of the tall peak FR -possible over excursion- in the 100Hz range. If you EQ to a more "flatter" response, you may not hear this with tolerable listening volumes. Staye tuned, I just may come up with more crazy thoughts. 1 Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 16, 2016 Share Posted January 16, 2016 Was this w/o EQ? Yes Quote Link to comment Share on other sites More sharing options...
The Dude Posted January 16, 2016 Share Posted January 16, 2016 Could this be because the 15c has a very low xmax? (2.4mm) It could be, I didn't realize it was so low. Could this be why it may be better in the upper frequencies? I am curious to see how the K33 and Crites cast performs as I have three of the Crites cast and I could put the 15c in the Cornwalls. Quote Link to comment Share on other sites More sharing options...
Zoef Posted January 16, 2016 Share Posted January 16, 2016 Dana uses a 3 inch slot with the k33e. Are you using this now? (Maybe i missed a post) Quote Link to comment Share on other sites More sharing options...
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