That may be leaning towards a "car woofer", and will most likely need some extra power/volume to hear good bass.
Whats nice these days are the quick-view recommendations right on the spec sheet.
e.g. these go a little lower in a sightly bigger box, good price also:
Dayton Audio DC200-8 8" Classic Woofer | 295-310
FYI - PE has that free shipping deal over $100 and don't forget the coupon codes, can save another $5 - $10.
(some of the other sites charge shipping and handing!!!)
Cut any wood this weekend?
Whats nice these days are the quick-view recommendations right on the spec sheet.
e.g. these go a little lower in a sightly bigger box, good price also:
Dayton Audio DC200-8 8" Classic Woofer | 295-310
FYI - PE has that free shipping deal over $100 and don't forget the coupon codes, can save another $5 - $10.
(some of the other sites charge shipping and handing!!!)
Cut any wood this weekend?
started to, but nothings finished yet. in my continuing of learning the finer points of this hobby, and correct me if I'm but the sensitivity of the drivers should be the same across the board so if the focals have a 91db and I want to add 2 woofer to make it a 3way the woofers would need to be 88db to give a a total of 91db.
for woofers I'm looking a cast basket around $50 each give or take trying to keep the parts not including the wood to around $400 6 woofers and crossover components
for woofers I'm looking a cast basket around $50 each give or take trying to keep the parts not including the wood to around $400 6 woofers and crossover components
2 drivers in series = 0dB gain
2 drivers in parallel = +6dB in gain
You are missing baffle step loss in the equation - typically about a 4 to 6dB loss below a frequency that is dependent on the baffle width - the wider the baffle the lower the frequency where the drop starts occurring.
So if you choose 88dB woofers in parallel, you get 88 + 6 = 94dB and then subtract about 4dB for baffle step = 90dB. Now just use a resistor to lower the mid and perhaps the tweeter to match. You are better off choosing a woofer sensitivity (after baffle step loss) that will be a little lower than the tweeter and mid. You do not want to lower the output of the woofers with resistors.
Note the driver ratings can be in both 1W/1m sensitivity and in 2.83V/m efficiency. They are not equivalent. Make sure you are comparing apples to apples.
2 drivers in parallel = +6dB in gain
You are missing baffle step loss in the equation - typically about a 4 to 6dB loss below a frequency that is dependent on the baffle width - the wider the baffle the lower the frequency where the drop starts occurring.
So if you choose 88dB woofers in parallel, you get 88 + 6 = 94dB and then subtract about 4dB for baffle step = 90dB. Now just use a resistor to lower the mid and perhaps the tweeter to match. You are better off choosing a woofer sensitivity (after baffle step loss) that will be a little lower than the tweeter and mid. You do not want to lower the output of the woofers with resistors.
Note the driver ratings can be in both 1W/1m sensitivity and in 2.83V/m efficiency. They are not equivalent. Make sure you are comparing apples to apples.
baffle step loss? if there is a layman definition or explanation? if not ill just take your word for it.
When the wavelengths are short, the sound is essentially only playing in the forward hemisphere. When the wavelengths get longer than the width of the baffle then they start wrap around the cabinet and play in both the forward and backward hemispheres - in twice as much space in other words. Thus in the listening position, they will lose about 4-6dB. So the highs end up louder than the lows in a gradual transition dependent on the baffle width.
See here for more detail: bafflestep
Or if you have Excel try this little program
Loudspeaker Design Software
Or if not, try this one
Tolvan Data
See here for more detail: bafflestep
Or if you have Excel try this little program
Loudspeaker Design Software
Or if not, try this one
Tolvan Data
Please go read the paper on True Audio about this. He summarized Olsons work very well.
True Audio's Loudspeaker Design Tech Topics Index
2g60, still pondering two thoughts:
(1) how are you going to power all these speakers?, assuming you want to hear the widows rattle.
(2) how are you going to cross over in this 80 - 100 range for the three "up front" speakers. No passive xo will do that, not without spending a fortune
I keep going back to one simple idea, making the "bass bottoms" and add a plate amps to each one, i.e. each speaker would need 120v power, but I think its pretty good plan.
So many woofers out there, I'm still thinking the soft suspension 8" MCM woofer is a candidate, I've have 6 playing at one time - scary bass !!!
[might want to blue tape your windows]
(1) how are you going to power all these speakers?, assuming you want to hear the widows rattle.
(2) how are you going to cross over in this 80 - 100 range for the three "up front" speakers. No passive xo will do that, not without spending a fortune
I keep going back to one simple idea, making the "bass bottoms" and add a plate amps to each one, i.e. each speaker would need 120v power, but I think its pretty good plan.
So many woofers out there, I'm still thinking the soft suspension 8" MCM woofer is a candidate, I've have 6 playing at one time - scary bass !!!
[might want to blue tape your windows]
I was thinking 800-1200hz thats why I wanted 8" instead of 12"s. I still plan on using a subwoofer that will be crossed over at 80 - 100hz. I'm not necessarily looking for window rattleing I just like a good rich sound, and I'm a firm believer in there's no replacement for displacement. as for power, I'm in the market for a new receiver but the plan is a 5.1 receiver with the possibility of an outboard amp for the mains as I have an old carver amp that i havent used much just sitting there
well after messing with stuff, and things over the holiday. I built some cabinets and crossovers, and now I'm confused. i used the crossovers from the focals with a 50uf capacitor that if i understand things correctly should block everything below 1000hz at 4 ohms and i used a 1.5mh which should block everything above 1000hz allowing the focal crossover to do the 5kz crossover for the tweeter and midrange. after all put together hooked them up and they sound good, or at least to me but back to my question, the focal drivers are getting everything up to 5kz and if i understand the basics of crossovers the 50uf cap should block or filter those frequencies below 1000hz out. what am i not getting?
Hard to follow 2g did you build the three ways or bass bottoms?
One cap is not going to make a adequate xo; also the impedance of the driver is very important.
Some pics or sketch out a block diagram would help a lot.
One cap is not going to make a adequate xo; also the impedance of the driver is very important.
Some pics or sketch out a block diagram would help a lot.
i built 3ways using the planned focals with there crossovers and 2 8in 4ohm each wired in series to get 8 ohms and made a simple 2way crossover to go between the 8s and the focal crossover.
as for a capacitor i only used it as a component to cut the frequency to the focal crossover to above 1k unless i'm missing something that should work
as for a capacitor i only used it as a component to cut the frequency to the focal crossover to above 1k unless i'm missing something that should work
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