hello,
i want to pair a 8" full range vented enclosure (around 65 liters) with a woofer/subwoofer (can be any size). is this not a good idea? most of these WAW/FAST configurations i have seen have full range that are 5" or smaller, with a 6-12" woofer. why not use a larger full range ?
the full range is to be used inside a lively cafe, and then paired with the woofer/sub for outdoor events/partys (around 30-50 people). i really want the full range to be vented bc i like the look of it, and the woofer/sub would be in a separate cabinet.
for the 8" full range driver i was thinking of using jbl 328c (ojas fan), but i cant find the detailed TS parameters for it. otherwise maybe the dayton audio PS220-8 8" neo driver, or the SB Acoustics SB20FRPC30-8" (amazing reviews, but the price is so low its makes me doubt it). i have previously used lii audio fast 8", also vented enclosure in around 65L, but the highs were piercing in some frequencies. the bass was good though, but never fully tested for large outdoor parties.
for the woofer/sub i have no idea, i cant even figure out if this sort of a combination makes any sense or if it would be a woofer or a sub. does anyone have any advice on which it should be, and any driver recomendations? should this also be ported or is that up to me? at what frequency would i xo?
i cant find many configurations pairing a 8" full range with a woofer, except for lii audio which has a configuration of 8" full range and woofer, but it is on an open baffle. maybe this configurations (8" with sub/woofer) doesnt exist bc the full range already covers the lows? should is be a subwoofer? i thought for a outdoor event the lows would get drained out and hence would want to pair it with a woofer/sub.
i want to pair a 8" full range vented enclosure (around 65 liters) with a woofer/subwoofer (can be any size). is this not a good idea? most of these WAW/FAST configurations i have seen have full range that are 5" or smaller, with a 6-12" woofer. why not use a larger full range ?
the full range is to be used inside a lively cafe, and then paired with the woofer/sub for outdoor events/partys (around 30-50 people). i really want the full range to be vented bc i like the look of it, and the woofer/sub would be in a separate cabinet.
for the 8" full range driver i was thinking of using jbl 328c (ojas fan), but i cant find the detailed TS parameters for it. otherwise maybe the dayton audio PS220-8 8" neo driver, or the SB Acoustics SB20FRPC30-8" (amazing reviews, but the price is so low its makes me doubt it). i have previously used lii audio fast 8", also vented enclosure in around 65L, but the highs were piercing in some frequencies. the bass was good though, but never fully tested for large outdoor parties.
for the woofer/sub i have no idea, i cant even figure out if this sort of a combination makes any sense or if it would be a woofer or a sub. does anyone have any advice on which it should be, and any driver recomendations? should this also be ported or is that up to me? at what frequency would i xo?
i cant find many configurations pairing a 8" full range with a woofer, except for lii audio which has a configuration of 8" full range and woofer, but it is on an open baffle. maybe this configurations (8" with sub/woofer) doesnt exist bc the full range already covers the lows? should is be a subwoofer? i thought for a outdoor event the lows would get drained out and hence would want to pair it with a woofer/sub.
Oh, they exist. Generally speaking, for most home audio people tend to pair (sub)woofers with smaller wideband mid-tweeters because (at least as far as currently available units go) the latter typically have a cleaner response & tend to be more consistent off-axis. Since they are usually run sealed, with a crossover, power-handling tends not to be a major issue either, assuming it's done well.
You can run the wideband vented, but unless you're running it unfiltered, with the sub brought in < about 40Hz or so, power-handling tends to be reduced as the vented box unloads 24dB/octave below tuning, leaving the driver unsupported & potentially running to extreme excursions.
Since you're wanting something for (presumably background) material in a cafe, using a larger wideband makes sense if that's the route you want to be taking as it's less about hi-fi & more a pro-audio setting. The JBL is a physical & electrical coax, not a wideband driver in the usual sense; as I recall, JBL specify suitable box volumes etc. so all you'd need to do is partner with your choice of active subwoofer. The Dayton & SB I would simply suggest putting in a Butterworth aligned sealed box, and again, run with your choice of active subwoofer/subwoofers, preferably those which provide a high-pass option for the mains. If you really like the appearance of a vented, I'd simply stick the end of a duct on the box & paint it black. In a pro-audio setting you'd typically be better off with a reasonable grill to provide some protection for the drivers though, so that's usually a bit of a non-issue. YMMV as always of course.
You can run the wideband vented, but unless you're running it unfiltered, with the sub brought in < about 40Hz or so, power-handling tends to be reduced as the vented box unloads 24dB/octave below tuning, leaving the driver unsupported & potentially running to extreme excursions.
Since you're wanting something for (presumably background) material in a cafe, using a larger wideband makes sense if that's the route you want to be taking as it's less about hi-fi & more a pro-audio setting. The JBL is a physical & electrical coax, not a wideband driver in the usual sense; as I recall, JBL specify suitable box volumes etc. so all you'd need to do is partner with your choice of active subwoofer. The Dayton & SB I would simply suggest putting in a Butterworth aligned sealed box, and again, run with your choice of active subwoofer/subwoofers, preferably those which provide a high-pass option for the mains. If you really like the appearance of a vented, I'd simply stick the end of a duct on the box & paint it black. In a pro-audio setting you'd typically be better off with a reasonable grill to provide some protection for the drivers though, so that's usually a bit of a non-issue. YMMV as always of course.
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Do you have a mic to collect your current frequency response? or how do you want to filter your 8" full-range?
If you don't have any and plan to DIY, I would suggest to get an IMM6 mic from PartsExpress and consder the 10" sub (like Dayton RSS265HF-4) and DSP plate amp (Dayton SPA500DSP or Hypex FA501) in a 1 ft^3 sealed box. I assume what you want is decent response from 100 to 45 Hz, not some 20Hz party. something like the kits from PE.
If you don't have any and plan to DIY, I would suggest to get an IMM6 mic from PartsExpress and consder the 10" sub (like Dayton RSS265HF-4) and DSP plate amp (Dayton SPA500DSP or Hypex FA501) in a 1 ft^3 sealed box. I assume what you want is decent response from 100 to 45 Hz, not some 20Hz party. something like the kits from PE.
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Larger wideband has limited high frequency performance and beaming off axis.
And many have a rising response on the top end as well.
Depending on woofer used crossover can be typical woofer frequency
crossover point or ideally near the baffle step.
And a smaller wideband is used for improved high end
and better off axis response.
lots of fancy names, it is basically a 2 way.
Far as 8" I have a thing for them too, im with yah.
larger cone can offer more efficiency depending on driver.
But high frequency performance is a big tradeoff.
Far as I understand the 328c is Coaxial so it is a 8"
with a tweeter. Or basically a coaxial with a Compression
driver. And includes the crossover.
Probably check the data sheet it is a ceiling speaker.
So includes a transformer for 70 volt systems.
Ojas likely bypasses the transformer and operates it
like a normal 8 ohm speaker.
Assume it could be high Qts like many ceiling speakers
so would need a large box
Technically adding a sub makes it a 3 way.
You could just use a 2 way active crossover to make things
easy and crossover at the typical 60 or 80 Hz.
either by listening or measurement determine if the sub needs
to be run reversed polarity. Which is fairly typical
Sub crossover is usual 60 to 80 Hz so venting the 8" is not needed
port wont do anything on a highpass.
Speakers are art as well so I get the attraction to cool looking ports.
Sub is going to likely be vented, so I would put design emphasis on
making the sub ports visually appealing.
8" is basically now a mid/midbass so data would be nice.
But it is sealed on a highpass so not as important.
Assuming again high Qts just make it large around 2 or 3 cubic feet.
And many have a rising response on the top end as well.
Depending on woofer used crossover can be typical woofer frequency
crossover point or ideally near the baffle step.
And a smaller wideband is used for improved high end
and better off axis response.
lots of fancy names, it is basically a 2 way.
Far as 8" I have a thing for them too, im with yah.
larger cone can offer more efficiency depending on driver.
But high frequency performance is a big tradeoff.
Far as I understand the 328c is Coaxial so it is a 8"
with a tweeter. Or basically a coaxial with a Compression
driver. And includes the crossover.
Probably check the data sheet it is a ceiling speaker.
So includes a transformer for 70 volt systems.
Ojas likely bypasses the transformer and operates it
like a normal 8 ohm speaker.
Assume it could be high Qts like many ceiling speakers
so would need a large box
Technically adding a sub makes it a 3 way.
You could just use a 2 way active crossover to make things
easy and crossover at the typical 60 or 80 Hz.
either by listening or measurement determine if the sub needs
to be run reversed polarity. Which is fairly typical
Sub crossover is usual 60 to 80 Hz so venting the 8" is not needed
port wont do anything on a highpass.
Speakers are art as well so I get the attraction to cool looking ports.
Sub is going to likely be vented, so I would put design emphasis on
making the sub ports visually appealing.
8" is basically now a mid/midbass so data would be nice.
But it is sealed on a highpass so not as important.
Assuming again high Qts just make it large around 2 or 3 cubic feet.
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wow thank you for all these answers! this is so appreciated <3 its so hard to commit to doing something because of all the options and varying specifications, and this makes me feel supported.
when you say unfiltered here, do you mean that the system has no XO, since the FR wont even hit 40 Hz anyways? and additionally filtering the sub to not go above 40 Hz? that would be awesome because i would love to avoid having to get a XO
also regarding this,
" If you really like the appearance of a vented, I'd simply stick the end of a duct on the box & paint it black. In a pro-audio setting you'd typically be better off with a reasonable grill to provide some protection for the drivers though, so that's usually a bit of a non-issue. YMMV as always of course."
do you say this because you dont recommend vented for any of the FR?
when you say unfiltered here, do you mean that the system has no XO, since the FR wont even hit 40 Hz anyways? and additionally filtering the sub to not go above 40 Hz? that would be awesome because i would love to avoid having to get a XO
also regarding this,
" If you really like the appearance of a vented, I'd simply stick the end of a duct on the box & paint it black. In a pro-audio setting you'd typically be better off with a reasonable grill to provide some protection for the drivers though, so that's usually a bit of a non-issue. YMMV as always of course."
do you say this because you dont recommend vented for any of the FR?
yes i do have a mic! i have the behringer ecm8000
i guess i assumed the amplifier i got would be doing the XO job, so i would use that amp when i am using the subs (party events), but then day to day the FR would be used alone, no sub, and said FR would go down as low as possible uninhibited. are there amps that do this that you suggest? you are correct, i would only want a need response to go down to 45, not 20.
i am pretty novice in this. i previously did a vented box using a LII audio 8" fast driver, and the highs were a bit piercing, so i attempted to make a notch filter but failed (it produced 0% change lol). so i think i will just buy those already made going forward, if you have any recommendations.
oh you are right its technically a 3 way with the coaxial!
ok so i would XO at 70 Hz. given that i want to use the FR also as a standalone system inside the cafe, and only whip out the subs for parties, hopefully i would be able to have the amp switch on/off the XO, so that when the FR are standalone, they are covering as much of the lows as possible. then, when there is a party, i switch on the XO, and the FR are only going down to 70 Hz (the vent is not being used). given this, then it would make sense to make the FR vented right? so that when they are standalone, they are still covering more of the frequency spectrum
do these sort of amps that have XO toggle on/off exist? i really hope so. thank you so much for your answer !
No, because there currently is no system, and every system varies from others. What I'm saying is that if you run any wideband drive unit in a vented box, it will eventually unload 24db/octave below its tuning frequency, whatever that may happen to be (this is just a law of physics). Therefore in a pro-audio application, power-handling will be limited if you don't high-pass it. That being the case, you might as well run it sealed for improved power-handling & bring the sub / subs in a bit higher to avoid the chance of mechanical failure at high SPLs. The subwoofer will need some form of crossover, which is usually handled by an active plate amplifier, the better examples of which will also have some form of high pass for the satellite speakers.
I've designed literally thousands of vented enclosures, most of which can be found on this forum, so no, I've no issue with vented enclosures per se, taken as a general type. I don't recommend them for this particular application though, since other loads will likely prove more suitable.
A straightforward BR enclosure with the Tangband W8-2145, eight-inch fullranger will get you an F3 at about fifty hertz. With some tweaking of fb and volumes will get you below fifty hertz. If you want that extra thirty hertz or so, easily done...but at the expense of a rather huge subwoofer. BTW, I'm currently modeling a fifteen-inch driver to get an f3 of about 14 hertz, & the enclosure is slightly over one cubic meter, 1010 liters.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
Yes they do since it is a installation.
So rackmount system be easy to do.
1 active crossover unit, and for stereo 2x 2 channel power amps.
One side powers the Highs one side powers the sub.
So 2 amps 2 channels needed.
The important part for a sub would be over excursion.
Sub would be tuned around usual 25 to 30 Hz and you run
a high pass excursion filter to protect it from unloading.
Behringer Super X pro CX2310 V2
Would do that.
It has switches to mute each crossover.
And also has a 25 Hz over excursion filter.
Then of course crossover points adjustable
and gain can be set.
As 2way it is stereo or mono three way.
So perfect one unit as a stereo 2 way.
Dont let sub output confuss you.
You use using high low outputs.
Set it to 100 Hz 120 Hz , click the 25 Hz filter.
Adjust gains your done. If sub needs inversion ( likely)
hit the inv button.
Far as the
JBL 328c
I read the owners manual.
On the front ring it has built in ports.
JBL uses a 1 cubic foot enclosure box.
Measure the port area, and length and reverse
engineer the port tuning.
As you see the rated -3dB I believe is 100 Hz
So its not a bass monster. I doubt you will turn off the sub.
Ojas removes the ring and made his own ports.
Your application. Suggest higher crossover 100 to 120 Hz
port wont do anything. But in live audio it has been done
for midbass. Ports dont do anything, but the enclosure is
vented which would help exhaust heat for thermal ratings.
Or just use the metal ring, ports are there already.
1 cubic foot box and all done
Ceiling provides a wide baffle.
And JBL did use a nice 18 dB crossover.
Would make the baffle as large as possible.
To be friendly to the likely crossover design.
Bypass the transformer you can see 2 leads going to the
crossover to run as 8 ohms.
Zillion options for sub.
328c on high pass will get going pretty good.
But not a SPL monster, Direct Radiator will keep up
with it. Make it simple Go for
Eminence LAB15
Use the Vented Medium Club cabinet design
on page 7.
4.5 cubic feet , tuned 30 Hz
tap that 25 Hz excursion filter on the Behringer
and done.
Greets!
Hmm, on paper the lii audio fast 8" can only do ~100 dB/m/2pi/5 W at low distortion and even then only from ~100 Hz - up, so ~103 dB/stereo, so kind of surprised it's loud enough in a 'lively' cafe.
Regardless, for outdoor parties it's best to design as 4pi space and 50 folks is generally a pretty big area, i.e.~108 ft^2 dance floor + ~8 ft^2*50 = 400 ft^2 = sqrt(508 ft^2) = ~22.5 ft square or ~22.5*sqrt(2) = ~32 ft diagonally for auditorium style seating.
If we accept 100 dB/m as sufficient, then 100 dB/3.281 ft (m) drops ~ 6 dB every doubling of distance = ~ ln(32/3.281)/ln(2) = ~3.286x 6 = ~ -20 dB, so need up to ~120 dB dynamic headroom = ~117 dB/stereo or about what relatively inexpensive prosound coax drivers such as the Eminence Beta-8CX w/ASD1001 CD co-ax are rated for on average down to ~250 Hz/4pi, so need a prosound (sub) woofer XO'd > ~250*sqrt(2) = ~350 Hz, which at this high you can make it a typical BR tuned low if you want, though for only the 'look', but better to seal it @ ~0.707 Qtc and drop XO to 300 Hz where female vocals start.
Hmm, on paper the lii audio fast 8" can only do ~100 dB/m/2pi/5 W at low distortion and even then only from ~100 Hz - up, so ~103 dB/stereo, so kind of surprised it's loud enough in a 'lively' cafe.
Regardless, for outdoor parties it's best to design as 4pi space and 50 folks is generally a pretty big area, i.e.~108 ft^2 dance floor + ~8 ft^2*50 = 400 ft^2 = sqrt(508 ft^2) = ~22.5 ft square or ~22.5*sqrt(2) = ~32 ft diagonally for auditorium style seating.
If we accept 100 dB/m as sufficient, then 100 dB/3.281 ft (m) drops ~ 6 dB every doubling of distance = ~ ln(32/3.281)/ln(2) = ~3.286x 6 = ~ -20 dB, so need up to ~120 dB dynamic headroom = ~117 dB/stereo or about what relatively inexpensive prosound coax drivers such as the Eminence Beta-8CX w/ASD1001 CD co-ax are rated for on average down to ~250 Hz/4pi, so need a prosound (sub) woofer XO'd > ~250*sqrt(2) = ~350 Hz, which at this high you can make it a typical BR tuned low if you want, though for only the 'look', but better to seal it @ ~0.707 Qtc and drop XO to 300 Hz where female vocals start.
Ok understood! Thank you. So what would you suggest ? Given our system is made to be alone (FR for inside a lively cafe) and also combine with woofer (for outdoor parties in the night time every now and then) , what would you suggest?
I don’t know how easy it would be to combine and undoo the combination, but we would be willing to pay to make it easy
I don’t know how easy it would be to combine and undoo the combination, but we would be willing to pay to make it easy
In a WAW you are typically crossing over high enuff that, unless you want to play LOUD in a large room, a smaller midTweeter will provide sufficient levels, better dispersion, and mid/top.
Of the many 8” FRs i can only recommend a couple, the SEAS FA22 and the Visaton B200. Both really need phase plugs.
FA22 in 65 litres sealed does a really decent job in the bass, In the low 30s in about 40 litres, the reflex is 75 litres, doesn’t go lower really but will be better in a room woth little room gain (or if you prefer too much bottom). If you were to add a woofer somewher ebelow 40-60 Hz.
B200 is problemtic in a box, one of the few 8s you can get bass ou tof on a large enuff OB. Mate it with a woofer and the OB size/shape determines XO point.
dave
Of the many 8” FRs i can only recommend a couple, the SEAS FA22 and the Visaton B200. Both really need phase plugs.
FA22 in 65 litres sealed does a really decent job in the bass, In the low 30s in about 40 litres, the reflex is 75 litres, doesn’t go lower really but will be better in a room woth little room gain (or if you prefer too much bottom). If you were to add a woofer somewher ebelow 40-60 Hz.
B200 is problemtic in a box, one of the few 8s you can get bass ou tof on a large enuff OB. Mate it with a woofer and the OB size/shape determines XO point.
dave
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Anybody know the thermal rating for the Lii Song fast 8 ?
Its cool you like the Ojas stuff.
He does Altec influenced style
with modern twist
Be awesome to do a modern braced Altec 614/612 style box for
the sub and use the 8" with a horn or tweet.
Ojas did a horn upgrade.
interesting to hear what the 328c actually does.
But hey I get the silver wrinkle finish thing.
Im huge fan of the silver/black Altec utility boxes.
be easy to go beta8 add a horn.
either way 15" sub would stay.
Or Highpass the Lii and see how it keeps up.
probably add a tweet/horn
Once we know baffle size can actually look
at what happens in sim. Im a sucker for white cones.
It is a pretty driver. wont do 117dB. On highpass
maybe 105 to 110 depending on thermal rating
Its cool you like the Ojas stuff.
He does Altec influenced style
with modern twist
Be awesome to do a modern braced Altec 614/612 style box for
the sub and use the 8" with a horn or tweet.
Ojas did a horn upgrade.
interesting to hear what the 328c actually does.
But hey I get the silver wrinkle finish thing.
Im huge fan of the silver/black Altec utility boxes.
be easy to go beta8 add a horn.
either way 15" sub would stay.
Or Highpass the Lii and see how it keeps up.
probably add a tweet/horn
Once we know baffle size can actually look
at what happens in sim. Im a sucker for white cones.
It is a pretty driver. wont do 117dB. On highpass
maybe 105 to 110 depending on thermal rating
I've already suggested a mains choice/range if you don't need the extra bass for indoors, otherwise need to add/XO at least an 8" mid-bass woofer (Emminence Beta 8A in this case) to the mains with the presumption that the mains will be pole mounted with a separate pair of 'stereo' sub systems ('all in one' with amp/XO) located near/at each mains' pole stands/bases for special occasions/outdoor apps.
With the cost of DSP dropping quicker than I can keep up, it's the 'no-brainer' choice for XOs, dialing in (separately saving) the speakers/room and outdoors match up instead of in my time when we chose best overall compromise or used separate systems.
???
i think we are going to do something like in the picture below. the sub is kind of modeled after altec but taller. its not fully pictured either but we will have the top stack hovering over the bottom so that the FR isnt disturbed by sub vibrations.
please remember the top stack will be sitting separated most of the time, so thats why we are using 8" FR. i understand that together the two pieces arent the most "smart" combination, bc im loosing out on better highs by using 8" FR instead of a mid/tweeter.
completely separate, but do you guys know anything about using recycled plastic as the enclosure material? MDF has a density of .80 g/cm3, and recycled plastic .91g/cm3 (when using recycled plastic bottle tops), so this makes me think it would be OK. 16mm thickness
thank you all!
please remember the top stack will be sitting separated most of the time, so thats why we are using 8" FR. i understand that together the two pieces arent the most "smart" combination, bc im loosing out on better highs by using 8" FR instead of a mid/tweeter.
completely separate, but do you guys know anything about using recycled plastic as the enclosure material? MDF has a density of .80 g/cm3, and recycled plastic .91g/cm3 (when using recycled plastic bottle tops), so this makes me think it would be OK. 16mm thickness
thank you all!
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thanks gm! so to confirm, you were suggesting the Emminence Beta 8A as a sub ? or as instead of the 8" FR driver?