[whippersnapper]

Hello everyone. I was told this is helpful forum and I need some advice. This is my first OB build. I'm wondering if the Edge sims I'm doing are accurate as far as bass response. Here are two sims of my OB with folded back wings and floor image included. Because I'm not sure the upper woofer will couple with the floor which is "more" correct? The upper woofer is 22" from the floor so I wonder if it will couple well enough to get this mirror image? Also will the ever increasing depth of the wing make for a screwy response? How about integration with the mid? I did this because it seemed like sort of a good compromise between a flat baffle (good mid integration, poor bass with most baffle widths) and a U baffle (good bass, poor integration with mid over a certain frequency). FYI I did alot of work to find a good XO point considering floor bounce issues, mid excursion, combing, etc. and came up with 350Hz as the best compromise for those factors.





Until I measure the actual baffle i'm not sure where F3 will fall. Best case is 90Hz as shown. I'm thinking this should mesh well enough with the monopole sub with reciever's XO set around 60-80 Hz. I hope anyway...

Thanks,
Brandon

[MJK]

Brandon,

The EDGE is a very good program but it only shows you the influence of the baffle. It does not include the response of the driver, you only have one piece of the puzzle.

Martin

[Rudolf]

Brandon,
I saw you presenting your mirror image sim on three different LS-forums and not getting much help except the advice to not stretch EDGE beyond its limitations - which is a perfectly good advice.

Martin certainly is too gentlemanlike to praise his own dipole simulation software to the skies - so I will do it for him :
His simulation software is as near to building the baffle itself as it gets, because it integrates driver parameters, floor and front wall influence. His worksheets don´t (yet?) allow for a baffle design exactly like yours, but it probably could be approximated by simulating a flat baffle for the mid and two U-frames for the lower and upper woofer respectively.

If you need a more precise simulation model than EDGE could deliver before building the baffle, you have to take the MJK way.

Rudolf

[scorpion]

MJK's MathCad models are the most developed for OB simulation so far. However Svante Granqvist, Edge developer, also has his Basta software which will allow you to do a far field OB-simulation for your chosen baffle design, chosen elements and crossovers. Basta will handle n-corner baffles. So that is a step up from Edge.

/Erling

[whippersnapper]

Thanks for the replies! I've been thinking of trying martin's software. I here about it a lot. At this point I'm just wondering how accurate the sim for just the baffle effects on bass response and whether the folded back tapered wings is a usable idea versus say a U baffle.

[ttan98]

I subscribe to MK's worksheets, they are very versatile and also have their limitations.

So far the worksheets include the following on OB projects:

1. stimulation of U frame, for 1 woofer
2. stimulation of H frame, for 1 woofer
3. 1 driver on open baffle
4. 2 drivers on open baffle
5. 3 drivers on open baffle

Ask Scorpion he build OB speakers based on MK worksheet.

for only US$25 to gain access it is a steal. There are other types of worksheets other than open baffle projects.