Hi snake69fast
If the price is not that big an issue, I would suggest BMS 18N862.
That is available in Europe, Lean Business Audio in the UK have a good price on them.
You can read Troel Graversens description of them. He uses them in The Loudspeaker.
In the beginning of the developmenty they are in a U-frame open baffle, read hes comments about that.
best regards
uwe
PS they have linear Xmax of +/- 19 mm
PPS the Faital Pro 18fh510 has +/- 5,75 mm
If the price is not that big an issue, I would suggest BMS 18N862.
That is available in Europe, Lean Business Audio in the UK have a good price on them.
You can read Troel Graversens description of them. He uses them in The Loudspeaker.
In the beginning of the developmenty they are in a U-frame open baffle, read hes comments about that.
best regards
uwe
PS they have linear Xmax of +/- 19 mm
PPS the Faital Pro 18fh510 has +/- 5,75 mm
Those seem like strange choices for an OB newbie. Especially one who's asking about crossovers. Nice and large as they might be.
. The BMS x-max is impressive!With the low to medium Qts you'll need a whopping big mount of EQ to get the tonal balance right. That's not something most first time OB builders know how to do. Having been there myself - and heard too many "no bass" open baffles - it seems unlikely that Snakefast would get good results. At least the weak magnet Alpha will have some bass on the baffle without too much EQ/crossover work.
I would recommend fining a 15 or 18 with a low Fs and a Q of around 0.6-0.7. That makes for a very clean sound on open baffle and doesn't take heroic crossover tricks.
Build the OB portion of your speakers to function above your room transition frequency region (Schroeder frequency.) Build separate enclosed speaker(s) for low frequencies below your transition zone.
Power each driver individually with an inexpensive class-D amp. Use a DSP for your crossover and EQ. Unless you're selling these speakers to the mass market. In that case you can torture yourself with passive crossovers.
Here is a suggestion you may like to investigate.
SB Acoustics :: 12” SB34NRX75-16
Wire two of these in parallel ( per channel)and you'll have the sensitivity and Sd necessary for good OB bass response. Certainly it may be a little more expensive than a single driver but OB requires a large cone displacement associated with large cone surface area, all that optimized with a QTS around 0.7.
It is much better to start with drivers designed for the purpose rather than waste money on those that are going to fall short of one's expectations.
CM
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A big inductor will set you back almost $40 these days. Certainly more than that in the UK. And you'd need two for stereo. Although with a higher Q woofer (or two) you'd want a smaller coil.
Solid Core Inductor Crossover Coils in the Speaker Components Department at Parts Express | 299
There is your amp+DSP budget. $80
Solid Core Inductor Crossover Coils in the Speaker Components Department at Parts Express | 299
There is your amp+DSP budget. $80
True, it's nice to have better inductors, but the 16 gauge work well in practice. That bit of extra DCR ups the Q a little.
Depending on what you're doing, you may not need giant caps on the low pass. I invite you to see this:
Fast, fun, Inexpensive OB project
See also posts #854 and #1059
Open baffle crossovers are not like box crossovers, and it can take some time to get used to that. Sill, I've done the plate amp on OB woofer thing several times and quite liked it. It's nice to have choices.
Depending on what you're doing, you may not need giant caps on the low pass. I invite you to see this:
Fast, fun, Inexpensive OB project
See also posts #854 and #1059
Open baffle crossovers are not like box crossovers, and it can take some time to get used to that. Sill, I've done the plate amp on OB woofer thing several times and quite liked it. It's nice to have choices.
I'm surprised so many DIYers still intentionally design bass into their mains by default. Especially the open baffle guys. Linkwitz had to use four expensive drivers (> $1,000 for all four) in his OB subs + DSP and amps.
None of the desirable aspects of OB apply to low frequency subs. So, why do it?
None of the desirable aspects of OB apply to low frequency subs. So, why do it?
snake69fast
They sure have a large enough Xmax (+/- 16 mm) , low Fs and ok Qts, so why not:
Pano
If you pick the right inductor and let that one cut low down, you can do it passive. It will cost you some efficiency but the rated efficiency for all woofers is
allways up in the midrange never in the bas.
What I forgot to say was that I would go active, at least with a plate amp for the woofer.
The SB Acoustics 12" woofers are made for OB (look at the pole vent, no hissing there), have a large Xmax, are 16 ohm (two in parallel=8 ohm) and low Fs
They sure have a large enough Xmax (+/- 16 mm) , low Fs and ok Qts, so why not:
Pano
If you pick the right inductor and let that one cut low down, you can do it passive. It will cost you some efficiency but the rated efficiency for all woofers is
allways up in the midrange never in the bas.
What I forgot to say was that I would go active, at least with a plate amp for the woofer.
The SB Acoustics 12" woofers are made for OB (look at the pole vent, no hissing there), have a large Xmax, are 16 ohm (two in parallel=8 ohm) and low Fs
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