Hi
A budget, high sensitivity sealed 2 way build (94dB or more @ 2.8V) is something I would like to do at some point but I'm curious to find out how realistic it is.
It is voltage sensitivity that I care most about rather than power sensitivity.
4 ohm drivers would be probably be the better choice here.
High SPL capability and well extended bass are not important,
in fact overly extended bass is undesirable, an F3 around 60-80Hz is preferable.
Having already done some research there doesn't seem to be much shortage of low cost, high sensitivity tweeters.
Monacor DT-300 was one nice example, something similar in a 4 ohm version would do the job nicely.
Finding a high sensitivity woofer that is likely to play cleanly up over it's entire range is not as easy.
I love the tight and clean bass from alpair 11MS, so I figure looking for a woofer with similar qualities (low Le, low Mms and relatively high BL to Mms ratio) would be the best bet.
The Eminence Alpha 6C looked pretty much ideal along with the price but to my disappointment it wont extend enough to be suitable as a woofer in sealed enclosure.
Surprising is that the 8'' versions are barely any better.
I have not looked at larger one because I dont think they will have enough finesse up near XO point and the price only goes up.
Are large multi cone woofers (Eminence 12LTA, Fane 12TC250 etc.) the closest thing to what I want?
As an alternative, what about a wideband tweeter that could cross somewhat lower to a larger sized woofer, sacrificing treble quality and/or a bit of treble extension?
Full rangers will trade sensitivity to get more bass extension... seems reasonable to assume you could have a wide band tweeter with high sensitivity that is good down to 500Hz or so.
A budget, high sensitivity sealed 2 way build (94dB or more @ 2.8V) is something I would like to do at some point but I'm curious to find out how realistic it is.
It is voltage sensitivity that I care most about rather than power sensitivity.
4 ohm drivers would be probably be the better choice here.
High SPL capability and well extended bass are not important,
in fact overly extended bass is undesirable, an F3 around 60-80Hz is preferable.
Having already done some research there doesn't seem to be much shortage of low cost, high sensitivity tweeters.
Monacor DT-300 was one nice example, something similar in a 4 ohm version would do the job nicely.
Finding a high sensitivity woofer that is likely to play cleanly up over it's entire range is not as easy.
I love the tight and clean bass from alpair 11MS, so I figure looking for a woofer with similar qualities (low Le, low Mms and relatively high BL to Mms ratio) would be the best bet.
The Eminence Alpha 6C looked pretty much ideal along with the price but to my disappointment it wont extend enough to be suitable as a woofer in sealed enclosure.
Surprising is that the 8'' versions are barely any better.
I have not looked at larger one because I dont think they will have enough finesse up near XO point and the price only goes up.
Are large multi cone woofers (Eminence 12LTA, Fane 12TC250 etc.) the closest thing to what I want?
As an alternative, what about a wideband tweeter that could cross somewhat lower to a larger sized woofer, sacrificing treble quality and/or a bit of treble extension?
Full rangers will trade sensitivity to get more bass extension... seems reasonable to assume you could have a wide band tweeter with high sensitivity that is good down to 500Hz or so.
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This will do it with some to spare, but $$$$, so use as a guide for similar specs: http://greatplainsaudio.com/wp-content/uploads/2016/06/3127.pdf
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Keep in mind that if you build an array, you can get the sensitivity very high.
First time I heard the Bottlehead Straight 8 it melted my face off.
First time I heard the Bottlehead Straight 8 it melted my face off.
An array is another interesting way to approach this, I'll look around for low cost drivers that could work.
Another potential woofer is FaitalPRO 8FE200, bass extension is still limited but it ticks a lot of boxes for only €25. Just going ported would make a lot of sense here...
Another potential woofer is FaitalPRO 8FE200, bass extension is still limited but it ticks a lot of boxes for only €25. Just going ported would make a lot of sense here...
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The fane 12-250tc will give good bass, but only to about 50Hz sealed and only on low power (<25w) otherwise it runs out of steam due to limited xmax. The PRV Audio
PRV Audio 15W700 (80$) will do it better with a response to +/-40Hz sealed and still usable to about 1kHz. It will need a huge (250L) cabinet altough.
PRV Audio 15W700 (80$) will do it better with a response to +/-40Hz sealed and still usable to about 1kHz. It will need a huge (250L) cabinet altough.
Eminence beta 12cx coaxial should do, relatively cheap. You can put it into a relatively small box if you don't mind the bottom end. You could checkout 8cx and 10cx as well to get even smaller box but you start losing the overall sensitivity. There are probably more PA coaxial speakers that fit the sensitivity requirement but these are about the cheapest.
High sensitivity down low means big woofer and/or big box (or horn). Big woofer wants low crossover point to the tweeter so the design will end up having a compression driver or being a three-way system. You could trade-off directivity and other qualities if you insist having a large fullrange speaker or direct radiating dome tweeter with huge woofer. Cheap dictates there is going to be trade-off in audio quality so it just matter of picking the poison. Mind you a big box could cost more than the drivers.
I'd say the beta 12cx is about the cheapest way to get that sensitivity with reasonably sized enclosure and ease of build. Size the box so that the low extension requirement is met but no bigger to save some. You could compare other designs / options to that and see if you can better it having your goals in mind. Have fun!🙂
High sensitivity down low means big woofer and/or big box (or horn). Big woofer wants low crossover point to the tweeter so the design will end up having a compression driver or being a three-way system. You could trade-off directivity and other qualities if you insist having a large fullrange speaker or direct radiating dome tweeter with huge woofer. Cheap dictates there is going to be trade-off in audio quality so it just matter of picking the poison. Mind you a big box could cost more than the drivers.
I'd say the beta 12cx is about the cheapest way to get that sensitivity with reasonably sized enclosure and ease of build. Size the box so that the low extension requirement is met but no bigger to save some. You could compare other designs / options to that and see if you can better it having your goals in mind. Have fun!🙂
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Beta 12CX is not that sensitive and quite expensive considering some of the other available options, the accompanying tweeter is also not cheap.
It's looking like for a sealed woofer it will have to be a 10'' which would have to be Faital 10FE200 4 ohm, it is just so inexpensive that to even consider another suitable option would mean paying at least twice as much.
Moving to 10'' now shifts the difficulty towards finding a tweeter.
These are probably the 2 most realistic options:
1. BC25SC06-04, any crossover point is likely to be a compromise for one or both drivers
2. 3FE22 , the 3'' and 4'' neodynium versions of these have a slight rise in response above 1k compared to ferrite and could serve as wideband tweeter but still maybe a dB or so shy of being a comfortable match for the woofer.
The Fane (or PRV 10FR300 if it was available in Europe) does also achieve the desired requirements at a reasonable cost, I do feel like a 2 way would have the edge in fidelity (and it works out 30% cheaper) but who knows .
It's looking like for a sealed woofer it will have to be a 10'' which would have to be Faital 10FE200 4 ohm, it is just so inexpensive that to even consider another suitable option would mean paying at least twice as much.
Moving to 10'' now shifts the difficulty towards finding a tweeter.
These are probably the 2 most realistic options:
1. BC25SC06-04, any crossover point is likely to be a compromise for one or both drivers
2. 3FE22 , the 3'' and 4'' neodynium versions of these have a slight rise in response above 1k compared to ferrite and could serve as wideband tweeter but still maybe a dB or so shy of being a comfortable match for the woofer.
The Fane (or PRV 10FR300 if it was available in Europe) does also achieve the desired requirements at a reasonable cost, I do feel like a 2 way would have the edge in fidelity (and it works out 30% cheaper) but who knows .
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..the 3FE22 is not sensitive.
What you should be looking at are "Econowave" threads.
(..and while a cheap array can be done, it's difficult to do one that's sensitive into the treble and still sounds "correct": as-in mixing in some upper mid-rang line-source with point-source *treble. Plus, it's near impossible to achieve the -3db point you want with smaller cheaper drivers in sealed box with a cheap array without more expensive corrective networks padding the response down significantly.)
*line-source treble in a significantly large array tends to get expensive (..particularly because it often requires going quite low in freq. to maintain a higher sensitivity.)
What you should be looking at are "Econowave" threads.
(..and while a cheap array can be done, it's difficult to do one that's sensitive into the treble and still sounds "correct": as-in mixing in some upper mid-rang line-source with point-source *treble. Plus, it's near impossible to achieve the -3db point you want with smaller cheaper drivers in sealed box with a cheap array without more expensive corrective networks padding the response down significantly.)
*line-source treble in a significantly large array tends to get expensive (..particularly because it often requires going quite low in freq. to maintain a higher sensitivity.)
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Well yeah it is a balancing act, few db's less sensitivity and a bit cheaper drivers. But now there needs to be a back chamber for the mid so a bit more extra work.
If labor is calculated as cost then the 12cx has a strong advantage. Buy a ready made car sub box, solder few parts for xo and call it finished. Apt50 driver is only 30e or something but cheapest often is a let down. Ultimate cheapest would be to look for some used PA gear.
Anyway, many possibilities and builder picks the most suitable one. Lots of fun thinking about the options for the design. Have fun! 🙂
If labor is calculated as cost then the 12cx has a strong advantage. Buy a ready made car sub box, solder few parts for xo and call it finished. Apt50 driver is only 30e or something but cheapest often is a let down. Ultimate cheapest would be to look for some used PA gear.
Anyway, many possibilities and builder picks the most suitable one. Lots of fun thinking about the options for the design. Have fun! 🙂
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Since it is voltage sensitivity that matters the 4 ohm 3fe22 already has 3dB advantage over 8 ohm equivalent, assuming the datasheets are reliable it reaches 90dB+ beyond 500Hz where it will be used.
Minimum 93dB@2.8V would be pretty good for low cost build.
The chamber needed for the fullrange is a slight annoyance and I was hoping to use a real tweeter for experience as I'm already familiar with what to expect using a full range as tweeter (better down low vs up top). With baffle step in mind there are probably more options for the tweeter now.
Minimum 93dB@2.8V would be pretty good for low cost build.
The chamber needed for the fullrange is a slight annoyance and I was hoping to use a real tweeter for experience as I'm already familiar with what to expect using a full range as tweeter (better down low vs up top). With baffle step in mind there are probably more options for the tweeter now.
You could factor in the possibility to turn the 10fe + 3fe 2-way into a 3-way by adding a tweeter afterwards at some later date.
In general, a 3-way system makes many design problems disappear while the trade-off is in the cost and complexity but it is all for allowing audio related goals to fulfill.
In general, a 3-way system makes many design problems disappear while the trade-off is in the cost and complexity but it is all for allowing audio related goals to fulfill.
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Yeah, that is a good plan. At these prices cost is not much of a tradeoff.
Spending more and getting higher sensitivity is also still on the table, will look into econowave and see what's achievable.
Spending more and getting higher sensitivity is also still on the table, will look into econowave and see what's achievable.
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I have a 8fE200 in a transmission line box.... Another hare brained project of mine. The box is an old Sony floorstander which I have enlarged the hole. Still working on the crossover and choosing the tweeter. Presently the tweeter is a beston RTC 003. Sound is not bad and goes pretty loud.
Will be an interesting project to pair it up with a 3FE22 (love them as well) Where the 3Fe22 handles the part above the baffle step frequency and the 8FE200 below that. You could consider running the 8FE200 open baffle too, if you like a spacious sound or add in a rear firing tweeter if sealed.
BTW, do you know there is now a 8FE300....
Oon
yeah, FE200 variants are the only ones available in 4ohm so didnt look at others.
4ohm FE300 would have been nice.
This.
You can pick up good gear for very little money if you aren't in a rush / wait for bargains to pop up.
PA gear tends to be ported - but works fine if you stuff the ports.
The OP says getting to 80Hz is OK, and that's roughly what you'd get from a typical pro 15" box.
FWIW, I've seen a Fountek ribbon shred itself - using a 3kHz second order crossover. Nine Inch Nails, 8-watt SET.
You could use two 8in drivers plus single tweeter in d'Appolito configuration.
Something like that MB 208/H | Visaton
Something like that MB 208/H | Visaton