Hi all,
I am planning to build a pair of speakers for my PC. I am looking for some feedback on my preferred design concept and advice on driver selection.
Here are the facts;
1) Source will be PC sound card line level input full frequency range.
2) Low frequencies will be handled by a JBL 10" sub. The sub has adjustable crossover from 50 - 150 Hz.
3) The satellites will need to have shielded drivers as they will be sitting next to a monitor.
4) They will not need to produce very high SPL's as they will be about a metre from the listener. I will probably drive them with about 20W/Ch, I haven't built or bought a suitable amp yet but that is another project...
5) Budget for the drivers is about A$200 or US$140.
6) I would prefer drivers that retail in Australia.
7) My preferred design is an open baffle tilted back at about 15 degrees to point the drivers at the listener.
My questions are;
1) Is an open baffle design suitable in this situation and what are the design considerations?
2) Should I use a single full range driver or a two way design?
3) Would a ribbon tweeter be appropriate? affordable within my budget?
4) How small a midrange can I go and still get response to 150Hz in an open baffle? 100mm?
5) Can anyone point me to similar projects or to drivers that they have successfully used in similar circumstances?
Thanks
Howard
I am planning to build a pair of speakers for my PC. I am looking for some feedback on my preferred design concept and advice on driver selection.
Here are the facts;
1) Source will be PC sound card line level input full frequency range.
2) Low frequencies will be handled by a JBL 10" sub. The sub has adjustable crossover from 50 - 150 Hz.
3) The satellites will need to have shielded drivers as they will be sitting next to a monitor.
4) They will not need to produce very high SPL's as they will be about a metre from the listener. I will probably drive them with about 20W/Ch, I haven't built or bought a suitable amp yet but that is another project...
5) Budget for the drivers is about A$200 or US$140.
6) I would prefer drivers that retail in Australia.
7) My preferred design is an open baffle tilted back at about 15 degrees to point the drivers at the listener.
My questions are;
1) Is an open baffle design suitable in this situation and what are the design considerations?
2) Should I use a single full range driver or a two way design?
3) Would a ribbon tweeter be appropriate? affordable within my budget?
4) How small a midrange can I go and still get response to 150Hz in an open baffle? 100mm?
5) Can anyone point me to similar projects or to drivers that they have successfully used in similar circumstances?
Thanks
Howard
Hi,
do a search here in the forums for the Tangband W3-781S fullrange driver. As you plan in a sub anyway they might be the perfect companion.
I´ve got some for my PC setup and they´re perfect for nearfield listening but don´t have enough low end.
You might wanna use two per side to get more output from them.
Or cross them over at >200Hz.
do a search here in the forums for the Tangband W3-781S fullrange driver. As you plan in a sub anyway they might be the perfect companion.
I´ve got some for my PC setup and they´re perfect for nearfield listening but don´t have enough low end.
You might wanna use two per side to get more output from them.
Or cross them over at >200Hz.
I would do a box, either sealed or ported which ever is required to get suitable bass extension to meet the sub. Id choose sealed if possible but ported would be fine also.
Open baffles simply will not work unless you are prepared to have pretty damn large panels next to your PC or lots of EQ to boost the bass, which small 3" low xmax drivers wont handle IMO.
How far an open baffle will go down is to do with the baffle size not the driver, obviously the driver will set how low the system can go, like in a normal box, but its before that that matters when diffraction takes place.
If you wanted to go two way then an audax 3" midbass paired with either the TM025F1 tweeter or the even cheaper TW010F1 mylar dome would do nicely.
As you are in australia Wes components, ill have a look now what they sell
A peerless 811435 tweeter and a vifa TC08SD49-08
mid/bass I think woud suit also.
The other suggestions are good too mindyou and will work out cheaper I'd imagine,although if you cannot get the tangband or fostex in aus then it might be cheaper to buy direct from wes.
Either way there my idea.
Open baffles simply will not work unless you are prepared to have pretty damn large panels next to your PC or lots of EQ to boost the bass, which small 3" low xmax drivers wont handle IMO.
How far an open baffle will go down is to do with the baffle size not the driver, obviously the driver will set how low the system can go, like in a normal box, but its before that that matters when diffraction takes place.
If you wanted to go two way then an audax 3" midbass paired with either the TM025F1 tweeter or the even cheaper TW010F1 mylar dome would do nicely.
As you are in australia Wes components, ill have a look now what they sell
A peerless 811435 tweeter and a vifa TC08SD49-08mid/bass I think woud suit also.
The other suggestions are good too mindyou and will work out cheaper I'd imagine,although if you cannot get the tangband or fostex in aus then it might be cheaper to buy direct from wes.
Either way there my idea.
I've been contemplating PC speakers that consist of a tall vented box (~16" or close to ear level) with two TB W3-871S like the CSS Elf 1.5 but in bipole configuration. It would give a little better bass response and a more open sound than the standard forward firing design. You could roll off the rear driver if you wanted.
(more do, less think
)
(more do, less think
)
Tim,
With a dipole dont you need to space it far away from a wall, or other surface? I might be missing something here, but all my computers have been up against a wall or in a cabinet. If I am mistaking the requirements for dipoles then I would be really happy because I wanted to build your dipole pipe but I dont have the room to space it away from a wall significantly.
Milo
With a dipole dont you need to space it far away from a wall, or other surface? I might be missing something here, but all my computers have been up against a wall or in a cabinet. If I am mistaking the requirements for dipoles then I would be really happy because I wanted to build your dipole pipe but I dont have the room to space it away from a wall significantly.
Milo
If you have about 2 feet behind them you should be fine. I understand PCs get pushed back but do your speakers also? I guess I'm envisioning a desktop PC using a CRT display. The speakers would be next to the front of the display which should put them out far enough to work ok. If it's in one of those little workstations pushed into a cubbyhole it wouldn't work well.
Timn8ter said:I've been contemplating PC speakers that consist of a tall vented box (~16" or close to ear level) with two TB W3-871S like the CSS Elf 1.5 but in bipole configuration. It would give a little better bass response and a more open sound than the standard forward firing design. You could roll off the rear driver if you wanted.
(more do, less think
Approximately how wide and deep would such a speaker be?
joensd said:
I wouldn't cross over at > 200Hz
I have this issue with my monsoon planar 14 PC speakers where the sub crosses over to the planar sats at around 200Hz.
The problem is that a 200Hz note is directional ie. you can locate where the sub is, ... I managed to overcome this issue somewhat by positioning the sub in line with the PC user and equidistant from the satellites but this arrangement may not be optimal for everyone.
I would look for sats that can meet the sub somewhere below 100Hz.
Yes, you are absolutely right. Should have mentioned that myself.
But also as you said positioning of a sub for the PC shouldn´t be too hard (and make a nice stand for a printer)or let´s say stereo subs are too much.
I am soon about to finish a ML-TQWT with the Tangband W3-871S which hopefully gives me enough bass ( down to 65Hz) to go without a sub. If I´m lucky with the setup I´ll be back soon.
coolkhoa said:
Coolkhoa,
I am currently getting a price on these from the distributor.
They are shielded ribbon tweeters.
http://www.wagner.net.au/pae/Ventura/RibbonTweeter.htm
Thanks
Howard
5th element said:
5th Element,
The drivers I am looking at all have Fs below 100Hz which is below the crossover point to the sub of say 150Hz.
I am completely new to the open baffle concept. Could you please explain what kind of response a small 4-5" driver will give in an open baffle?
Thanks
Howard
ozynigma said:
OK when the wavelength of the sound roughly reaches the width of the baffle sound diffracts round the edges. Now the wider the baffle the lower this happens. With a dipole when this happens the front and the rear wave cancel each other because they are out of phase with each other. Now my 30cm wide baffles start to do this at about 500hz and are 12dB down at 125hz and you dont want a 30cm wide baffle on your desktop.
OB's work great for your application
I use OB's on my desktop with really big nice sound and super cheap. You only need a 22" baffle width to get 150hz, but I'd go wider to have more flexibility with your sub's setting. All you have to do is fold back the "wings" and end up with a front baffle width the size of the speakers. In addition to being able to get great sound, you can do it super cheap. I use a 5 driver array of 4" TV speakers on each side with a total cost of $18 plus some duct tape. $15 for 10 drivers, $3 for some posterboard with the styrofoam sandwiched in the center. I got lucky and the cheapest 4"ers I found sounded the best.
An array will help cheapies sound much better than a single one because driver excursion is so much less for the same volume.
You can find decent sounding drivers in the $1-$3 range. If your really want them very close to your monitor you'll need shielded which might cost a little more. If you can get more than about 18" away from your monitor you'll get better sound and not need shielded drivers. With big tall sound you don't want a narrow soundstage.
Find a supply house that has replacement speakers for TV's, cars, etc. You can listen to a lot different speakers to find those you like in the 3"-5" range. For listening hold it in your hands and what you are looking for in addition to good overall sound is that they really come alive when you wrap your index fingers and thumbs around the outer edge to form a mini baffle. Look for extended upper range to avoid the need for a tweeter.
Spend $10 or so picking out a few different ones that you like the best. Then use cardboard and tape to make a test baffle to see how they really sound at home. Which ever you like the best, buy some more and put 4 or 5 of them in a column on the cardboard baffle as close together as possible. Fold the sides back for some stability and put it on a table, so your ears are in the vertical plain of the array and give it a listen. A/B it with whatever box speakers you have for a real eye opener. If there's not much bass don't worry. The key is do you like the sound that's there? Better vocals than you've ever heard before, big open sound, etc.
If you really need a tweeter, then pick up a pair of the cheap titanium bullet tweeters for cars for under $25 for a pair and an Lpad. I know they're quite harsh out of the box, but stuff small pieces of soft foam rubber (about the size of a pencil eraser) down between the sides of the horn and the center "bullet" cone. Start with 3 equally spaced and tune to taste. I usually end up with 6 leaving only small unfilled gaps. This will tame the harshness and really bring out the detail. You'll need the Lpad to lower their volume because they are very efficient. Mount them at ear level on your desktop baffles. They come with a cap, so you probably won't need any crossover.
Experiment with the baffle size. If you get lucky and end up with higher Qts speakers, which is common for TV speakers, then you can get even more of that great OB bass with longer wings and set your sub cutoff lower.
I'm still using by original test baffle. I guess someday I'll get around to making permanent baffles to improve the looks.
Import duties are a bear down here, so you should be able to find something good for even cheaper than I did if you shop around.
It's a fun, easy and cheap project that will be a real eye opener in terms of sound if you haven't heard an OB array before.
I use OB's on my desktop with really big nice sound and super cheap. You only need a 22" baffle width to get 150hz, but I'd go wider to have more flexibility with your sub's setting. All you have to do is fold back the "wings" and end up with a front baffle width the size of the speakers. In addition to being able to get great sound, you can do it super cheap. I use a 5 driver array of 4" TV speakers on each side with a total cost of $18 plus some duct tape. $15 for 10 drivers, $3 for some posterboard with the styrofoam sandwiched in the center. I got lucky and the cheapest 4"ers I found sounded the best.
An array will help cheapies sound much better than a single one because driver excursion is so much less for the same volume.
You can find decent sounding drivers in the $1-$3 range. If your really want them very close to your monitor you'll need shielded which might cost a little more. If you can get more than about 18" away from your monitor you'll get better sound and not need shielded drivers. With big tall sound you don't want a narrow soundstage.
Find a supply house that has replacement speakers for TV's, cars, etc. You can listen to a lot different speakers to find those you like in the 3"-5" range. For listening hold it in your hands and what you are looking for in addition to good overall sound is that they really come alive when you wrap your index fingers and thumbs around the outer edge to form a mini baffle. Look for extended upper range to avoid the need for a tweeter.
Spend $10 or so picking out a few different ones that you like the best. Then use cardboard and tape to make a test baffle to see how they really sound at home. Which ever you like the best, buy some more and put 4 or 5 of them in a column on the cardboard baffle as close together as possible. Fold the sides back for some stability and put it on a table, so your ears are in the vertical plain of the array and give it a listen. A/B it with whatever box speakers you have for a real eye opener. If there's not much bass don't worry. The key is do you like the sound that's there? Better vocals than you've ever heard before, big open sound, etc.
If you really need a tweeter, then pick up a pair of the cheap titanium bullet tweeters for cars for under $25 for a pair and an Lpad. I know they're quite harsh out of the box, but stuff small pieces of soft foam rubber (about the size of a pencil eraser) down between the sides of the horn and the center "bullet" cone. Start with 3 equally spaced and tune to taste. I usually end up with 6 leaving only small unfilled gaps. This will tame the harshness and really bring out the detail. You'll need the Lpad to lower their volume because they are very efficient. Mount them at ear level on your desktop baffles. They come with a cap, so you probably won't need any crossover.
Experiment with the baffle size. If you get lucky and end up with higher Qts speakers, which is common for TV speakers, then you can get even more of that great OB bass with longer wings and set your sub cutoff lower.
I'm still using by original test baffle. I guess someday I'll get around to making permanent baffles to improve the looks.
Import duties are a bear down here, so you should be able to find something good for even cheaper than I did if you shop around.
It's a fun, easy and cheap project that will be a real eye opener in terms of sound if you haven't heard an OB array before.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.