This is my first " almost completed now " real loudspeaker project.
I based it at 90% on info that i have gathered from this website, so i wish to thank you all for exchaging your ideas and knowledge on this forum !
This project makes use of 8 ( 4 per side ) hi-Vi AS2 drivers
HI-VI AS2 @ parts express
The price was right, the looks were there, but most importantly,
the response graph was what i was looking for ...
Comments on this driver? maybe someone here has used it already ??
Neway, so the project is a dipole radiator OB line array, or whateever u wish to call it these days..
as it uses 4 drivers per side in an effort to gain higher sensitivity, and lower distortion from the drivers
( also i thought that 4 2" would still play good high hz, and have more volume to play down to the 300hz range .. )
I use pine wood to build this, this was also the second time in woodworking of my life, first timer was 2 months ago when i constructed a nice rack for my audio video gears ..
I added the aluminum insert as i thought it would match with the aluminum drivers, and i think it does it pretty well
here are pics of the assembled system ..
I based it at 90% on info that i have gathered from this website, so i wish to thank you all for exchaging your ideas and knowledge on this forum !
This project makes use of 8 ( 4 per side ) hi-Vi AS2 drivers
HI-VI AS2 @ parts express
An externally hosted image should be here but it was not working when we last tested it.
The price was right, the looks were there, but most importantly,
the response graph was what i was looking for ...
Comments on this driver? maybe someone here has used it already ??
Neway, so the project is a dipole radiator OB line array, or whateever u wish to call it these days..
as it uses 4 drivers per side in an effort to gain higher sensitivity, and lower distortion from the drivers
( also i thought that 4 2" would still play good high hz, and have more volume to play down to the 300hz range .. )
I use pine wood to build this, this was also the second time in woodworking of my life, first timer was 2 months ago when i constructed a nice rack for my audio video gears ..
I added the aluminum insert as i thought it would match with the aluminum drivers, and i think it does it pretty well
here are pics of the assembled system ..
Attachments
picture again ..
bon ...
this project is a Gift from me to my brother for his b-day + Xmas
Its intended use is in a small room, on desktop as computer/dvd/video games system .
It should be powered by an old 1970 Akai receiver ( 20W ? )
It had to be small enough to fit on his desk
it will be listened in near range ( 60-100cm )
and also at 2-3m range ( dvd/TV )
I didn't want to fiddle with crossover for this first project,
that is the main reason why i choosed wide range drivers ..
i will make him a small sub ( maybe 2 times 8" in a sealed box )
next spring ..
i ain't sure of the freq response of this system , but with a few calculations and decustions, i think it should start falling down at aprox 200hz pretty steeply combining the drivers F3 point and the OB effect ..
it should be pretty easy to make the crossover for the subs to match if it indeed starts falling down at ~200hz
( that's what i planned, but hey! i know nothing, just guessing here !!! ahhaha )
So what do you think ?
bon ...
this project is a Gift from me to my brother for his b-day + Xmas
Its intended use is in a small room, on desktop as computer/dvd/video games system .
It should be powered by an old 1970 Akai receiver ( 20W ? )
It had to be small enough to fit on his desk
it will be listened in near range ( 60-100cm )
and also at 2-3m range ( dvd/TV )
I didn't want to fiddle with crossover for this first project,
that is the main reason why i choosed wide range drivers ..
i will make him a small sub ( maybe 2 times 8" in a sealed box )
next spring ..
i ain't sure of the freq response of this system , but with a few calculations and decustions, i think it should start falling down at aprox 200hz pretty steeply combining the drivers F3 point and the OB effect ..
it should be pretty easy to make the crossover for the subs to match if it indeed starts falling down at ~200hz
( that's what i planned, but hey! i know nothing, just guessing here !!! ahhaha )
So what do you think ?
Attachments
ok so the wiring should be ok ..
but WHAT A BREAK IN!!!
OMFG!!
they went from not there at all ..
to super detailed in 2 hours of listening !!!!
It is the first time i can play the speakers to such a low volume that u don't even hear anything after 2 meters..but yet in nearfield they sound just as good as when the volume is up!
the bass is just not there though...as i thought it would
but WHAT A BREAK IN!!!
OMFG!!
they went from not there at all ..
to super detailed in 2 hours of listening !!!!
It is the first time i can play the speakers to such a low volume that u don't even hear anything after 2 meters..but yet in nearfield they sound just as good as when the volume is up!
the bass is just not there though...as i thought it would
Cool looking little drivers. Even though the array is so short you are still going to get some line array effect at least at some frequencies because the listening distance is so close. To verify
this, listen to them with your head level with them and stand up slowly. If as your ears pass the top of the line they get much more quiet, then you need to tilt them back so the center of the speaker line points to ear level.
Also, it looks like PE screwed up and posted the incorrect FR graph for those drivers. No way they are flat down to 100hz except when they are turned off. The specs say 500-15000hz which is much more realistic. That means no bass no matter what you do and you also don't need a baffle nearly that size.
All is not lost. You have room on the baffle for some small woofers and use those for tweeters.
this, listen to them with your head level with them and stand up slowly. If as your ears pass the top of the line they get much more quiet, then you need to tilt them back so the center of the speaker line points to ear level.
Also, it looks like PE screwed up and posted the incorrect FR graph for those drivers. No way they are flat down to 100hz except when they are turned off. The specs say 500-15000hz which is much more realistic. That means no bass no matter what you do and you also don't need a baffle nearly that size.
All is not lost. You have room on the baffle for some small woofers and use those for tweeters.
Nice looking speakers. They are real step up from most first (or second or...) projects. I have always loved the look of those drivers. I think they are fine for near field use at a computer. You don't need to get very loud to have a nice experience. Your brother is lucky.
I think you probably have the wiring correct but I can understand why they wouldn't play very loud or low. The efficiency rating of the speakers (and all these small Hi-Vi speakers) are very low - in your case it is 78 db. This is about 10 db less than average drivers. The other limiting factor is the size of the cone which is probably not much more than 1.5 " effective diamter. The X-max of 1.5 mm is good for such a small driver but, combined with the cone area, can't move much air - which is critical for bass. Even the four drivers togther is problaly only equal to a single 3 or 4 inch driver with an Xmax of 1.5 mm. Open baffles are less efficient down low, because of cancellation effects from the back wave. Even with your wings you may still get some cancellation. I think the response graph is probably correct, but you could not expect to get much bass below4-500 hz given the cone size and XMax.
I think you probably have the wiring correct but I can understand why they wouldn't play very loud or low. The efficiency rating of the speakers (and all these small Hi-Vi speakers) are very low - in your case it is 78 db. This is about 10 db less than average drivers. The other limiting factor is the size of the cone which is probably not much more than 1.5 " effective diamter. The X-max of 1.5 mm is good for such a small driver but, combined with the cone area, can't move much air - which is critical for bass. Even the four drivers togther is problaly only equal to a single 3 or 4 inch driver with an Xmax of 1.5 mm. Open baffles are less efficient down low, because of cancellation effects from the back wave. Even with your wings you may still get some cancellation. I think the response graph is probably correct, but you could not expect to get much bass below4-500 hz given the cone size and XMax.
dhenryp said:
I agree with the 4-500hz part, but the response graph needs to be the corrected. There's just no way a driver with an Fs of 153hz can be flat down to 100hz. Typically, those with an Fs of 100hz start rolling off at 200hz. Below Fs all drivers roll off steeply, I think at 12bd per octave.
I'd put the baffles even with the front edge of the monitor, to get them as close to you as possible. Tilt them up so your ears are in the center of the array plain and add 3 or 4 4" woofers plus a crossover at 500-600hz.
well thank you very much all for the comments!
I agree that it sounds like nothing is going on below 3-400hz
ahhaahhah
i didn't expect a 123hz FS neway
Although there is place on the side baffle for 1-2 4" woofers on each side, this project is already costing twice what it was supposed to ..
and i have seen nowhere of the stupid 78db efficiency
should've gather the info better ...
that is the reason why they sound so quiet!!!
this might be a problem with the akai, as it doesn't like to be driven hard ( lot's of clipping distortion ) and it doesn't send the same power as my 2B for sure
Well, u see, that is why i asked so many times people in here to put up a FAQ for noobs like me with recommendation and what to spot when looking for drivers ... i think that finding good drivers is the problematic of every noob
15Hz is sufficient for this system though ..but he'll need more bass soon ..i shall build him a small woofer thing
would using 1-2 woofers on the side baffle be enough ?
wouldn't it interfer with the tweeters sound ?
All in all, this little system sure plays good mid/highs
ahhaha ..very detailed even at low volume setting
super clear sound..but it lacks dynamics .. maybe just the air volume is not there
i seriously thought that by using multiple drivers of the same size it would help with the low end response.. nah ???
I agree that it sounds like nothing is going on below 3-400hz
ahhaahhah
i didn't expect a 123hz FS neway
Although there is place on the side baffle for 1-2 4" woofers on each side, this project is already costing twice what it was supposed to ..
and i have seen nowhere of the stupid 78db efficiency
should've gather the info better ...
that is the reason why they sound so quiet!!!
this might be a problem with the akai, as it doesn't like to be driven hard ( lot's of clipping distortion ) and it doesn't send the same power as my 2B for sure
Well, u see, that is why i asked so many times people in here to put up a FAQ for noobs like me with recommendation and what to spot when looking for drivers ... i think that finding good drivers is the problematic of every noob
15Hz is sufficient for this system though ..but he'll need more bass soon ..i shall build him a small woofer thing
would using 1-2 woofers on the side baffle be enough ?
wouldn't it interfer with the tweeters sound ?
All in all, this little system sure plays good mid/highs
ahhaha ..very detailed even at low volume setting
super clear sound..but it lacks dynamics .. maybe just the air volume is not there
i seriously thought that by using multiple drivers of the same size it would help with the low end response.. nah ???
Puis-je suis ton frere? Lucky man, getting speakers and subs for x-mas!
Well, using a lot of small drivers will give you the necessary volume displacement of low-end sound though, the characterstic that will hinder your low-end sound is the fs (free-air resonance frequency). This will determine the driver's natural (w/o active elctronics) sound.
You should add a sub-woofer of some sort, though you will need to make sure you match the levels of the speakers with the woofer. Use an L-pad and SPL meter if you have one. If your spacing is about 1-2 cm. the speakers should be operating as line arrays.
So, efficiency would become 84dB. (still too low for me) and Sensitivity would become 84dB. as well. (Both low.) You already knew that anyway though. If you have any questions on parameters you can search google or the forum--I've mentioned characteristics to be expected under certain conditions. I've learned a lot from reading, but you learn the most when you experiment!
Au-revoir.
Well, using a lot of small drivers will give you the necessary volume displacement of low-end sound though, the characterstic that will hinder your low-end sound is the fs (free-air resonance frequency). This will determine the driver's natural (w/o active elctronics) sound.
You should add a sub-woofer of some sort, though you will need to make sure you match the levels of the speakers with the woofer. Use an L-pad and SPL meter if you have one. If your spacing is about 1-2 cm. the speakers should be operating as line arrays.
So, efficiency would become 84dB. (still too low for me) and Sensitivity would become 84dB. as well. (Both low.) You already knew that anyway though. If you have any questions on parameters you can search google or the forum--I've mentioned characteristics to be expected under certain conditions. I've learned a lot from reading, but you learn the most when you experiment!
Au-revoir.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.