Hi Folks,
I want to do some more experimenting and have an idea for a BR box. After using WinISD I came up with a BR design of 16.4l tuned to 48.19Hz with 1 vent (47mm dia and 99.8mm length). does that sound right? I'm trying to get the bass to go low and reduce the size of the speaker wrt OB to maximize WAF.
This is what I'm thinking:
Your input would be greatly appreciated.
Cheers, Rafal
I want to do some more experimenting and have an idea for a BR box. After using WinISD I came up with a BR design of 16.4l tuned to 48.19Hz with 1 vent (47mm dia and 99.8mm length). does that sound right? I'm trying to get the bass to go low and reduce the size of the speaker wrt OB to maximize WAF.
This is what I'm thinking:
Your input would be greatly appreciated.
Cheers, Rafal
Attachments
That alignment seems reasonable. You'd have baffle-step losses around 1kHz (?) or so.
I'd build a quick 'n' dirty prototype before building boxes that fancy.
Have you checked out these designs:
http://www.planet10-hifi.com/boxes.html
I'd build a quick 'n' dirty prototype before building boxes that fancy.
Have you checked out these designs:
http://www.planet10-hifi.com/boxes.html
Rafal,
Nice idea for the BR's.
To bad you have to give up your OB's so fast?
They looked sweet and I thought you were going be the first to try a crossover and bass driver or 2 with them.
I searched 'FR125S' under loudspeakers/full range last night and, in addition to Planet10's plans, found some very nice designs, especially the HEGGs.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=68176&highlight=
R/
Jim
Nice idea for the BR's.
To bad you have to give up your OB's so fast?
They looked sweet and I thought you were going be the first to try a crossover and bass driver or 2 with them.
I searched 'FR125S' under loudspeakers/full range last night and, in addition to Planet10's plans, found some very nice designs, especially the HEGGs.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=68176&highlight=
R/
Jim
Thanks for your suggestions Jim,
I haven't given up on OB just yet. In fact, I'm currently listening to Diana Crall through them. Sounds very very nice. I'm just trying diferent ideas and I like to experiment.
I may still go for a nice, big bass driver, but I know so very little about XO design, that it's little intimidating.
Cheers,
Rafal
I haven't given up on OB just yet. In fact, I'm currently listening to Diana Crall through them. Sounds very very nice. I'm just trying diferent ideas and I like to experiment.
I may still go for a nice, big bass driver, but I know so very little about XO design, that it's little intimidating.
Cheers,
Rafal
Tell me about it!
I've broken with convention a bit and just purchased some Dayton Reference Series RS225 8" woofers for mine. I'm studying baffle loss, roll off points, acoustic and electrical roll offs and my head is swimming. The hard part is finding another person doing something very similar to what you're doing. 2 brains are almost alway better than 1.
All that and the fact that I feel the FR125S's need protection on the bottom end,.. from bottoming out to fast. It has me looking at higher order crossovers to preserve as much of their range as possible. The sum of the quality components for a 12db X-O cost almost as much as the drivers! Make a mistake there and wow, that'll hurt.
As for baffle step info, try these:
http://sound.westhost.com/bafflestep.htm
http://www.t-linespeakers.org/tech/bafflestep/index.html
I've also downloaded Xbaffle.xls and Edge freeware. A bit daunting but I think I'm making headway. Like my main / front baffle is 15"x36" and when you plug the FR125 values into Xbaffle at 30" up (762mm) it shows it's output plumit at about 200Hz. Somewhere close to there is where I'm going to have to cross my woofer.
I'm also looking at the 7L ported box plans that Planet10 has available. That's partly why I mentioned the HEGGS to you. The drivers sound to nice to let them sit for long and you may just have to use helpers for the bass.
R/
Jim
I've broken with convention a bit and just purchased some Dayton Reference Series RS225 8" woofers for mine. I'm studying baffle loss, roll off points, acoustic and electrical roll offs and my head is swimming. The hard part is finding another person doing something very similar to what you're doing. 2 brains are almost alway better than 1.
All that and the fact that I feel the FR125S's need protection on the bottom end,.. from bottoming out to fast. It has me looking at higher order crossovers to preserve as much of their range as possible. The sum of the quality components for a 12db X-O cost almost as much as the drivers! Make a mistake there and wow, that'll hurt.
As for baffle step info, try these:
http://sound.westhost.com/bafflestep.htm
http://www.t-linespeakers.org/tech/bafflestep/index.html
I've also downloaded Xbaffle.xls and Edge freeware. A bit daunting but I think I'm making headway. Like my main / front baffle is 15"x36" and when you plug the FR125 values into Xbaffle at 30" up (762mm) it shows it's output plumit at about 200Hz. Somewhere close to there is where I'm going to have to cross my woofer.
I'm also looking at the 7L ported box plans that Planet10 has available. That's partly why I mentioned the HEGGS to you. The drivers sound to nice to let them sit for long and you may just have to use helpers for the bass.
R/
Jim
Baffle step loss refers to the fact that higher frequencies only "see" half-space (i.e. radiate as if mounted on an infinite baffle) while lower frequencies "see" full-space (i.e. radiate like a point source in 3D). Thus, there is an apparent dropoff of signal below a certain frequency. The larger the speaker baffle, the lower the dropoff point.
IMO the best writeup is on quarter-wave.com (under general speaker articles)
IMO the best writeup is on quarter-wave.com (under general speaker articles)
Hi Jim,2litre said:
I like your thinking. I looked up the Dayton drivers and they are not too spendy. I may follow you down simillar path. I was thinking, however, that maybe we can just make a very simple XO. I think the simpler, the better. BTW, what amp are you using?
The other option is to make/buy an activea sub (maybe like a rythmik). Going with FR125Sin OB + a sub has it's advantages and may be easier to implement. It also affords more flexibilit should you choose to change the satelite drivers or enclosures.
I asked my wife, and she didn't agreee to making a larger baffle so I guess I will have to augment the bass some other way. Also, I think I'd like the FR125S positioned higher. closer to the ear level.
Rafal,
Right after I put mine in those 15"x19" baffles I tinkered with them in my living room and den (both fairly small) with my old 15wpc Pioneer SX-450. Played with height, distance from walls, seperation, rugs, etc. I was listening to all types of music, Santana, Steely Dan, George Benson, Andy Williams, Willie Nelson, Deep Purple, Brazil 66, Stanley Jordan and my crooner AM station KIXI-AM. During all that is where I experienced how fast they would bottom out.
Then I remembered my Boston 7" sub. Hooked that up and loved it! Set at about 80Hz and 1/3 gain I had sweet sound to 40Hz and I didn't have to stress the FR's so much. Took it down at the end of that weekend and I've yet to hook it all up again. So, I've done the active sub route and found it very satisfying in my small rooms. I'll try it again after I get the 7L boxes done and more capacitors to try.
I agree with your desire to use simple X-O's. I like them too. Generally they're easier on the brain and wallet. My 3-way NoBox is crossed low to mid at 125Hz, 1st order. I'm going to 'borrow' those components and try them out on the FR / RS set up. If it does well I'll buy some better components of the same values.
Sounds funky doesn't it? I mention that I really liked the sound of them with the active sub yet I'm still screwing around with a straight OB idea. Well I just want to try it all out. If it doesn't cut it, well I can use the RS225 as the bass unit in a sealed or ported system, either with or without plate amp. Heck, the 911 wasn't Ferdinand Porsche's first automotive design, he cut his teeth on the VW Beetle.
R/
Jim
Right after I put mine in those 15"x19" baffles I tinkered with them in my living room and den (both fairly small) with my old 15wpc Pioneer SX-450. Played with height, distance from walls, seperation, rugs, etc. I was listening to all types of music, Santana, Steely Dan, George Benson, Andy Williams, Willie Nelson, Deep Purple, Brazil 66, Stanley Jordan and my crooner AM station KIXI-AM. During all that is where I experienced how fast they would bottom out.
Then I remembered my Boston 7" sub. Hooked that up and loved it! Set at about 80Hz and 1/3 gain I had sweet sound to 40Hz and I didn't have to stress the FR's so much. Took it down at the end of that weekend and I've yet to hook it all up again. So, I've done the active sub route and found it very satisfying in my small rooms. I'll try it again after I get the 7L boxes done and more capacitors to try.
I agree with your desire to use simple X-O's. I like them too. Generally they're easier on the brain and wallet. My 3-way NoBox is crossed low to mid at 125Hz, 1st order. I'm going to 'borrow' those components and try them out on the FR / RS set up. If it does well I'll buy some better components of the same values.
Sounds funky doesn't it? I mention that I really liked the sound of them with the active sub yet I'm still screwing around with a straight OB idea. Well I just want to try it all out. If it doesn't cut it, well I can use the RS225 as the bass unit in a sealed or ported system, either with or without plate amp. Heck, the 911 wasn't Ferdinand Porsche's first automotive design, he cut his teeth on the VW Beetle.
R/
Jim
I started with the FR125 in OB, as well. I tried a few different baffle designs. At the same time I hooked up a few different drivers to better understand the OB sound. Using the FR125 in OB in an almost nearfield (6-10) alignment with the FR125 mounted low gave me the best results.
I have migrated to an aperiodic design and use the boxes for HT sattelites at present. The thread about the Northcreek aperiodic design and pics of a couple builds are here: http://www.diyaudio.com/forums/showthread.php?s=&threadid=59762&perpage=10&pagenumber=23. A thread on filters and crossovers for the FR125 is here: http://www.diyaudio.com/forums/showthread.php?s=&threadid=70255.
I believe the aperiodic enclosure suits the FR125 and my use fairly well. Trying to get a lot of bass and low end dynamics from a 4" driver is like teaching a pig to sing...doesn't sound good and pisses off the pig.
Augmenting the FR125 would probably yield good results. The dipole from Planet 10's site might do it for me with some music. I didn't think the FR125 needed any help on the higher end but some have added a tweeter.
Good luck on the build.
I have migrated to an aperiodic design and use the boxes for HT sattelites at present. The thread about the Northcreek aperiodic design and pics of a couple builds are here: http://www.diyaudio.com/forums/showthread.php?s=&threadid=59762&perpage=10&pagenumber=23. A thread on filters and crossovers for the FR125 is here: http://www.diyaudio.com/forums/showthread.php?s=&threadid=70255.
I believe the aperiodic enclosure suits the FR125 and my use fairly well. Trying to get a lot of bass and low end dynamics from a 4" driver is like teaching a pig to sing...doesn't sound good and pisses off the pig.
Augmenting the FR125 would probably yield good results. The dipole from Planet 10's site might do it for me with some music. I didn't think the FR125 needed any help on the higher end but some have added a tweeter.
Good luck on the build.
westend said:
I think you mean BIPOLE, sorry for the shout.
It's an interesting thing about the "pig farts" that some (myself included) have found with either the FR or WR125's in vented or MLTL enclosures. From personal experience and anecdotal reports, it seems to be amplifier related; i.e. problematic with both tubed and SS SE, but no issue with some P/P amps.
Dave's mini-onken design can be tuned to your room/system from fairly aperiodic to almost completely sealed by varying the amount of foam fill to the port slots. The "bipolars" were a 25L sealed, I preferred them overall to the onkens with either amp (best of all with the classA P/P EL84).
Rafal, interesting design - I tried something like that a few years back with a TMM ( PeerlessHDS /HiFi TN28) enclosure. If the box is small enough, you could probably get by with just a few layers of bending plywood around a curved rib frame. Using UF109 or any 2 part epoxy wood glue and the enclosure should be more than stiff enough, and resonances will be high enough frequency to be less of a problem.
Ya, Bibolar Bipoles, thanks Chris. They can be seen here: http://www.diyaudio.com/forums/showthread.php?s=&threadid=67053&highlight=. Any headway on the build Rafal?
Hi,
I'm still tinkering with the open baffle. I realy like the sound of mid freq. but I'm working on improving the low freq and taming the high freq. a bit. If I can't reach satisfactory results then I'll try the BR. Or maybe I'll just try it to play around with it for experimentation's sake.
The thing is, the OB does give me quiet satisfying mid-low freq, but I want to make sure I can hear the upright bass (the really big fiddle) which is so often used as a foundation for jazz recordings.
I'm still tinkering with the open baffle. I realy like the sound of mid freq. but I'm working on improving the low freq and taming the high freq. a bit. If I can't reach satisfactory results then I'll try the BR. Or maybe I'll just try it to play around with it for experimentation's sake.
The thing is, the OB does give me quiet satisfying mid-low freq, but I want to make sure I can hear the upright bass (the really big fiddle) which is so often used as a foundation for jazz recordings.
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