Hi. 😉wintermute said:
Yes, those Focal drivers aren't easy to crossover... I started with those drivers a long time ago !
My crossover is 24 dB Linkwitz Riley (acoustic), but the natural slope of the frequency response of the woofer at the FC allows me to use a more simple crossover design than the "classical" 4th order...
😉
Vincent
This is my second picture. I hope you understand my english!
My system consists the open speakers Prometheus from Bastanis and two dipole sub. I hear all kinds of music and i employ with music reproduction since 15 years. Now i am at the end of searching a loudspeaker system because i found a verry dynamic loudspeaker ( 100 db ) without every contorsion and very good voice reproduction. Im now able to hear many hours music without being nerved.
BR Dommi
My system consists the open speakers Prometheus from Bastanis and two dipole sub. I hear all kinds of music and i employ with music reproduction since 15 years. Now i am at the end of searching a loudspeaker system because i found a verry dynamic loudspeaker ( 100 db ) without every contorsion and very good voice reproduction. Im now able to hear many hours music without being nerved.
BR Dommi
Attachments
The "résonateur" is supposed to give the same bass response than the BR, but the main volume makes the mid/bass more "punchy" than a standard BR with only one big volume.
😉
Vincent
😉
Vincent
how do you calculate the box volumes and port length for this "résonateur", i find it very intriuging, might be just what i want for my next project.
"le résonateur"
Get the LSPCAD software from Ingemar Johansson, it simulates double reflex loading (= résonateur) as the only software that I know of.
There also was an article about that in the german magazine HobbyHifi, saying that basically trying to do a double reflex loading "by hand" can be a nightmare 'coz there are so many factors affecting the final result.
Get the LSPCAD software from Ingemar Johansson, it simulates double reflex loading (= résonateur) as the only software that I know of.
There also was an article about that in the german magazine HobbyHifi, saying that basically trying to do a double reflex loading "by hand" can be a nightmare 'coz there are so many factors affecting the final result.
This page explains how this "résonateur" works, but it's in french : http://pageperso.aol.fr/petoindominique/doc_htm/br.htm#reson (there is a .xls document in download to calculate a box) ; you can find some informations here too (in english this time 😉) in a different kind of box (2 ports in front of the box), but the calculation seems to be more appromixate : http://www.diysubwoofers.org/prt/dual_chamber.htm
I use LspCAD for simulating my projects, but the simulations of a "double tuned bass reflex 1" aren't at all in agreement with the calculations of Dominique Pétoin !
Another choice for this sort of box is to replace the internal port by three holes of a variable diameter (3 to 7 cm) in MDF. And It works great with LspCAD ! 🙂
😉
Vincent
I use LspCAD for simulating my projects, but the simulations of a "double tuned bass reflex 1" aren't at all in agreement with the calculations of Dominique Pétoin !
Another choice for this sort of box is to replace the internal port by three holes of a variable diameter (3 to 7 cm) in MDF. And It works great with LspCAD ! 🙂
😉
Vincent
Vincent,
I haven't done any simulations with LSPCAD on double tuned ...blabla myself (though a lot of other sims), but Mr. Timmermanns , tech editor of HobbyHifi, found close similarities in the simulations and actual measured results, done on a Visaton B200 fullrange driver. This driver with it's high Qts could be "tamed" to work in a double tuned reflex enclosure........
Salutations,
Oliver
😉
I haven't done any simulations with LSPCAD on double tuned ...blabla myself (though a lot of other sims), but Mr. Timmermanns , tech editor of HobbyHifi, found close similarities in the simulations and actual measured results, done on a Visaton B200 fullrange driver. This driver with it's high Qts could be "tamed" to work in a double tuned reflex enclosure........
Salutations,
Oliver
😉
Vince, this is the Double Chamber Reflex presented in 1961 by G.L.Auspurger. It is a completely different system from the Elipson-Fostex DBR-DCAAV!😱
Regards
Claudio
Dommi:
What's the XO between the ~Eminence and the tweeter?
Does the ~Eminence have a tweeter-cone? / Do you know anything about the frequency-respons of this driver?
Is the tweeter open-baffle or closed?
I'm asking these questions because I find it an interesting config, but it might also be wise to put some sound-damping on the wall behind the speakers, in the case that mid/high-frequencies are also backfired.
I also see an Audionet SAM amplifier, which confuses me in the sense that it's way overpowered for your system. More suitable options that come to mind: low powered triode, non-inverted chipamp or buffered inverted chipamp (DIY or commercial).
What's the XO between the ~Eminence and the tweeter?
Does the ~Eminence have a tweeter-cone? / Do you know anything about the frequency-respons of this driver?
Is the tweeter open-baffle or closed?
I'm asking these questions because I find it an interesting config, but it might also be wise to put some sound-damping on the wall behind the speakers, in the case that mid/high-frequencies are also backfired.
I also see an Audionet SAM amplifier, which confuses me in the sense that it's way overpowered for your system. More suitable options that come to mind: low powered triode, non-inverted chipamp or buffered inverted chipamp (DIY or commercial).
Thanks everybody to the differents experiences on the double tuned bass reflex. 😉
I will soon build new boxes for my loudpseakers, so I will compare the "résonateur" of Dominique Pétoin and that with the holes replacing the internal port : a friend of mine tell me that was quite easy to do and very effective. 🙂
I will surely post a topic to describe which is the better compared to a simple bass reflex box.
😉
Vincent
I will soon build new boxes for my loudpseakers, so I will compare the "résonateur" of Dominique Pétoin and that with the holes replacing the internal port : a friend of mine tell me that was quite easy to do and very effective. 🙂
I will surely post a topic to describe which is the better compared to a simple bass reflex box.
😉
Vincent
I believe that Bose used some type of DBR principle in the old Bose 701s. Apparently it's like double, triple, quadruple Reflex porting or something. Or wait, is it an Isobaric-BP design?
...thought i'd post a picture of my Straight 8's a Bottlehead kit.
they aren't as DIY as what most of you are doing, but for me they
were a project! I run these with a ~5 watt X-SOZ amp and a
BZLS pre. The 8's are very nice sounding speakers and have
satisfying bass without a sub. Great speakers for low watt amp
they aren't as DIY as what most of you are doing, but for me they
were a project! I run these with a ~5 watt X-SOZ amp and a
BZLS pre. The 8's are very nice sounding speakers and have
satisfying bass without a sub. Great speakers for low watt amp
Attachments
Poor quality pictures, but you get the idea...
http://home.earthlink.net/~mdis29a/images/newroom1.jpg
My apartment is incredibly cramped, thus the poor component positioning.
That's an NHT Model One on the far left. Sitting next to that is my broken Adcom GCD-600 and Harmon-Kardon ST-5 turntable, which I've just about got back into working order (like everything else, it was a thrift store find). Next to that is my computer rack--dual Athlon XP 1800s in the big box, PII-233 in the little box, and Sparc IIi 360 in the rack chassis under the monitor, if anyone cares. Component rack next to that, with my Classe CA-101 power amp and Kyocera DA-410cx CDP. Sitting atop the CDP is the world's crappiest passive preamp (a dual 10k, center-indexed pot salvaged from the tone control section of a 30 year old Proton receiver, soldered directly to some hacked-up interconnects, and all nailed to chunk of wood I pulled off a bird cage). Under the amp is my Paradigm sub.
http://home.earthlink.net/~mdis29a/images/newroom2.jpg
And that's the other half. The speaker stand is obviously DIY. I ran out of paint in the middle of finishing the thing this weekend
http://home.earthlink.net/~mdis29a/images/newroom1.jpg
My apartment is incredibly cramped, thus the poor component positioning.
That's an NHT Model One on the far left. Sitting next to that is my broken Adcom GCD-600 and Harmon-Kardon ST-5 turntable, which I've just about got back into working order (like everything else, it was a thrift store find). Next to that is my computer rack--dual Athlon XP 1800s in the big box, PII-233 in the little box, and Sparc IIi 360 in the rack chassis under the monitor, if anyone cares. Component rack next to that, with my Classe CA-101 power amp and Kyocera DA-410cx CDP. Sitting atop the CDP is the world's crappiest passive preamp (a dual 10k, center-indexed pot salvaged from the tone control section of a 30 year old Proton receiver, soldered directly to some hacked-up interconnects, and all nailed to chunk of wood I pulled off a bird cage). Under the amp is my Paradigm sub.
http://home.earthlink.net/~mdis29a/images/newroom2.jpg
And that's the other half. The speaker stand is obviously DIY. I ran out of paint in the middle of finishing the thing this weekend
That Bose is just your textbook 8th-order bandpass with extra port area to prevent chuffing. I hear it's like a 6th-order bandpass with an outer chamber tuned to Fs that actually passes the signal to the air.