Idontkno:
First off Mr BHFProfessional surely gets his share of free promotion from the LAB for his own "designs"(see his post below), but he calls you on the carpet for your post?
The determination of what is or is not appropriate for this forum is up to Craig. So I would not wory about your TX-9 vs SB850 post for right now. Follow to the end of this quote for some comments about the two subs in question.
"BHFProfessional
Messages: 203
Registered: August 2004
Location: West Lafayette, IN Has No Life
Stack two per side and get out of the way!
From the designer of the BH10 "Crusher" bass horn, which gave new meaning to "Portable Performance", comes the newest addition to the BHFProfessional family of professional high-performance horn speakers - the BHFProfessional V-2. The V-2 is a highly-specialized horn-loaded LF enclosure. It does not reach deeply into subwoofer frequencies, but it provides outstanding reinforcement to low frequency sound, with long-throw peformance that's tough to match. The V-2 is well at home in outdoor performances, where long throw and high output are priorities, while ultra-deep LF performance may not be. The enclosure itself is relatively compact: 20" wide x 28" deep x 36" high. Yet it horn-loades twin 15" woofers, which allows it to serve up concert-level LF with power and punch.
Real Performance:
Marketing-speak only gets you so far in the world of pro audio, where tangible benefits MUST be proven in order to prove a product's worth. Early simulations of the V-2's enclosure, which is like a W-bin on steroids (but with some notable improvements), show surprisingly good results. One enclosure has a +/-3dB response of 55-330 Hz, with a slight +3dB rise near 200 Hz, in the range commonly referred to as the "punch" frequencies, thus filling the greatest design goal of the V-2. Through the passband, the single enclosure has an average sensitivity of 108dB 1w/1m. The V-2 horn-loads two widely-available Peavey Black Widow BWX1508-8 woofers. These woofers have an added benefit: Field-replaceable basket/cone assemblies. When a woofer fails, it's usually the voice coil or suspension components. The precisely-machined metal components of the motor assembly can be removed from the back of the BWX-series woofers, and a new basket and cone assembly can be installed. This is less expensive than replacing entire woofers if a part of them should fail. For applications where extension to 55 hz is not sufficient (such as rap, hip-hop, R&B, and some flavors of pop), you can pair the V-2 with a folded horn subwoofer like the upcoming BH15 "Carnivore" folded horn subwoofer, featuring Peavey Low Rider subwoofer drivers with the same replaceable basket/cone features, but extended LF performance.
Timetable:
Expect more detailed simulation data and enclosure construction plans to be made available in February or March of 2005, unless interest is extremely high. Otherwise I'll just focus on getting some BH10 "Crusher" plans drawn using CAD.
[Updated on: Fri, 10 December 2004 19:09]
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Rory Buszka
BHFSpeakers
BHFProfessional"
The original TX-8 used the RCF L18p300. I believe the TX-9 did as well. Yorkville then switched to the B&C driver. There are some on the LAB (see archives) who believe the older version to be a better sub.
The original SB850 (not z) also had the RCF L18p300 drivers as well. I have heard that the Z version uses a variation of the AEB/18 Sound L18w1400. It is a very impressive driver at a very reasonable price. Universal music is the 18 Sound US distibutor
Both of these subs are pretty well respected subwoofers. From a DIY point of veiw, the TX-8s might be easier to build, but you want to reverse engineer the TX-9 which is not inproduction anymore.
I would not go by the quoted SPL specs for either box unless it is clarified if the spec is calculated or measured and under what circumstances.
Charlie Tappa @ pro sound service in Brain Tree MA is an expert on B&C and RCF drivers, perhaps he could give you a few pointers on your project. He would be able to clarify which driver from B&C would be the best replacement for the RCF L18p300. BTW Charlie will be one of RCF's new dealers and driver repair centers.
Welcome to the LAB. It seems to me that your question is "Sub Talk" and you are not promoting your own products or designs nor are you making your subs for commerical purposes.
Steve S