I'm toying with the idea of building a pair of small satellites with W3-871 (that I already have) & pairing them with a pair of small subs, with a passive crossover in the subs to begin with for simplicity's sake.
This is for my bedroom where I usually sit at my computer desk with my ears ~1.2m from the ground. The idea is that the satellites can be raised to that height & angled in toward my seating position whilst the subs can sit on the floor.
Michael Chua's system is essentially what I'm thinking of, however I suspect the subs he has there are far too large/powerful for my room. So I'm looking for recommendations of designs & drivers (that are available for purchase in the UK or from a reputable continental dealer (I will never deal with Europe Audio again!)) that would better suit the size of my room.
As far as amplification goes, there probably won't be more than 50W behind each channel & 'normal' listening conditions (eg when my flatmate is home) are less than 1W. I'm not looking for rumbling movie bass, but well defined 'music' bass.
See the attached picture for a better idea of the room/conditions.
This is for my bedroom where I usually sit at my computer desk with my ears ~1.2m from the ground. The idea is that the satellites can be raised to that height & angled in toward my seating position whilst the subs can sit on the floor.
Michael Chua's system is essentially what I'm thinking of, however I suspect the subs he has there are far too large/powerful for my room. So I'm looking for recommendations of designs & drivers (that are available for purchase in the UK or from a reputable continental dealer (I will never deal with Europe Audio again!)) that would better suit the size of my room.
As far as amplification goes, there probably won't be more than 50W behind each channel & 'normal' listening conditions (eg when my flatmate is home) are less than 1W. I'm not looking for rumbling movie bass, but well defined 'music' bass.
See the attached picture for a better idea of the room/conditions.
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could try blue planet audio , i've ordered a couple of times from them and have been impressed with the service . free delivery and arrived in a few days , they also have some of the smaller tang band subwoofers on sale at the moment .
steve
steve
The W8-670C on sale for €30 looks tempting but I can't find much info/experience with it online. Looks similar to the W8-740C though, so it should be quite good & I should be able to use some of the numerous W8-740C builds/designs as a starting point. Might buy a pair quick before they sell out...
Well I ordered a pair of the W8-670C because at that price they're worth experimenting with. Also grabbed a pair of W3-926SD for €11 each just to compare with the W3-871C (I'm still a bit miffed that I ended up with W3-871C which don't have phase plugs when I ordered W3-871 which do!).
Hey,
As I posted in my somewhat similar help needed thread:
http://www.diyaudio.com/forums/full-range/202282-help-needed-tb-w3-926sd-w8-670c.html#post2815668
I found specs for w8-670c on hobbyhifiladen.de. I am not sure how accurate they are though. Somehow the driver shows only on german version and not on english (atleast on me):
Tang Band W8-670C Tieftöner - Hobbyhifiladen
As I posted in my somewhat similar help needed thread:
http://www.diyaudio.com/forums/full-range/202282-help-needed-tb-w3-926sd-w8-670c.html#post2815668
I found specs for w8-670c on hobbyhifiladen.de. I am not sure how accurate they are though. Somehow the driver shows only on german version and not on english (atleast on me):
Tang Band W8-670C Tieftöner - Hobbyhifiladen
Time to bump my own thread with a specific question - what should the crossover frequency be? I seem to remember somebody telling me that a sub shouldn't play above ~120Hz as this is where the sound starts to become too directional.
However when I put as many TS parameters as I can find for the W3-871 (assuming that my W3-871C will behave roughly similar, even without phase plugs) into winisd (which I am no expert at) it looks like to achieve anything approaching 120Hz I'll have to build a ported cabinet. This surprises me because I've seen lots of people using (very small) sealed cabinets for these 3" drivers in combination with a sub.
Michael Chua (see link in first post) says he has crossed his at 125Hz, but from what I'm getting out of winisd there's no way his satellites are going anywhere near 125Hz. Am I missing something?
However when I put as many TS parameters as I can find for the W3-871 (assuming that my W3-871C will behave roughly similar, even without phase plugs) into winisd (which I am no expert at) it looks like to achieve anything approaching 120Hz I'll have to build a ported cabinet. This surprises me because I've seen lots of people using (very small) sealed cabinets for these 3" drivers in combination with a sub.
Michael Chua (see link in first post) says he has crossed his at 125Hz, but from what I'm getting out of winisd there's no way his satellites are going anywhere near 125Hz. Am I missing something?
I have that similar problem with the 926sd. 3l br tuned to 95 Hz was the best I could do.
But with that w8-670c I am clueless. I have no idea how to get reasonable small sub.
But with that w8-670c I am clueless. I have no idea how to get reasonable small sub.
I modeled the W3-926SD in almost exactly the same box as you, I got a 3l BR tuned to 97Hz.
I think I might leave my W3-871C for another project, because I can't find TS numbers for them unless I assume that they behave the same as the W3-871S which doesn't seem likely as the S have phase plugs & my C don't. Even then they don't look good in anything smaller than 5l which is getting a bit big for satellites.
For a BR the W8-670 doesn't look good in anything smaller than 1 cu ft (28l) which isn't small! It seems to work well in 4th order bandpass, but again only at about 1 cu ft. I'm using the TS values from the Tang Band site for the W8-670Q which looks the same as the but has a rubber surround instead of a foam surround.
Using both of my W8-670C in an isobaric box looks promising, but I have no idea where to start in designing that!
I think I might leave my W3-871C for another project, because I can't find TS numbers for them unless I assume that they behave the same as the W3-871S which doesn't seem likely as the S have phase plugs & my C don't. Even then they don't look good in anything smaller than 5l which is getting a bit big for satellites.
For a BR the W8-670 doesn't look good in anything smaller than 1 cu ft (28l) which isn't small! It seems to work well in 4th order bandpass, but again only at about 1 cu ft. I'm using the TS values from the Tang Band site for the W8-670Q which looks the same as the but has a rubber surround instead of a foam surround.
Using both of my W8-670C in an isobaric box looks promising, but I have no idea where to start in designing that!
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Hmm I started on winISD as well but now am playing with hornresp which seems a lot nicer in some respects (not intuitive design however). Hornresp for Dum... hmm... Everyone 😉 - Home Theater Forum and Systems - HomeTheaterShack.com I found this to be good starting point.
brohoof!
hurtz
brohoof!
hurtz
re xover frequency, I'd run them up to the the baffle step frequency, which will be considerably higher than 120Hz (Fbsc = 115/baffle width of satellites in metres) - baffle step correction solved;
depends on how you're going to place them in the room though
depends on how you're going to place them in the room though
" ..........an isobaric box looks promising, but I have no idea where to start in designing that!"
In an isobaric push-pull (Face to face), wired parallel, Vas is one-half (Liters/Cubic feet) , RE is also halved (Ohms), as is Lvc (mH) . PE (Watts) is doubled. All other Ts parameters stay the same.
___________________________________________________Rick..........
In an isobaric push-pull (Face to face), wired parallel, Vas is one-half (Liters/Cubic feet) , RE is also halved (Ohms), as is Lvc (mH) . PE (Watts) is doubled. All other Ts parameters stay the same.
___________________________________________________Rick..........
I don't even understand what the baffle step frequency is, so I'll do some reading on that tonight!
Thinking about it I would rather stick with 2x separate subs than a single isobaric, as it means I can use a single stereo amp or a pair of monoblocks combined with passive crossovers in the subs for a nice simple setup. For a 2.1 setup which I would have if I used both of my drivers for an isobaric sub, I would have to use 3x amps & somehow combine the bass frequencies from the 2x stereo channels to feed the sub (I use a DAC with a single stereo output).Richard Ellis said:
I've seen hornresp used loads over on speakerplans, I might have a look at it as well.hurtz said:
I guess now that we both use the w8-670c and w3-926sd we can combine our efforts in this one thread. Only difference is that you will use 2 subs and passive crossover. I will try to do without passive with low pass and computer.
I found technical data for the 670c. All the data was available at the blue planet acoustics but the download section shows only if you choose german language.. I notified Nick about it and hope it will be fixed at some point.
w8-670c:
http://oaudio.de/media/products/9f11c282a848aa63a8e.pdf
I will see if I have time today to try simulate box for the sub. I am guessing that we both agree that 926sd should go to ~3l br tuned near 100 Hz.
I found technical data for the 670c. All the data was available at the blue planet acoustics but the download section shows only if you choose german language.. I notified Nick about it and hope it will be fixed at some point.
w8-670c:
http://oaudio.de/media/products/9f11c282a848aa63a8e.pdf
I will see if I have time today to try simulate box for the sub. I am guessing that we both agree that 926sd should go to ~3l br tuned near 100 Hz.
Luckily my flatmate was home today because my speakers were delivered! Quite quick considering they came from Germany & well packed, so Blue Planet Acoustic definitely get a thumbs-up from me.
Thanks for the link to the official specs for the 670C, at least now my attempts to design a decent cabinet are only prevented by my inexperience rather than by using incorrect numbers!
~3l tuned to ~100Hz looks like the best plan for the 926SD. Forum user 'superlian' made a ~3.4l cabinet for W3-871S documented here (Norwegian but the dimensions are in the photos). Although winisd tells me that they won't play low enough with the 871S the 926SD in a similar enclosure should approach 100Hz before dropping beneath 0dB.
I don't know what the best shape for them is though - is it better for them to be thin & deep or wider & less deep? Does the 'optimal' button in winisd actually give the true optimal dimensions?
An externally hosted image should be here but it was not working when we last tested it.
Thanks for the link to the official specs for the 670C, at least now my attempts to design a decent cabinet are only prevented by my inexperience rather than by using incorrect numbers!
~3l tuned to ~100Hz looks like the best plan for the 926SD. Forum user 'superlian' made a ~3.4l cabinet for W3-871S documented here (Norwegian but the dimensions are in the photos). Although winisd tells me that they won't play low enough with the 871S the 926SD in a similar enclosure should approach 100Hz before dropping beneath 0dB.
I don't know what the best shape for them is though - is it better for them to be thin & deep or wider & less deep? Does the 'optimal' button in winisd actually give the true optimal dimensions?
Unfortunately it seems that one of my W8-670C is faulty. When the cone is displaced more than a certain amount (but still well within xmax) there is a distinct click sound from the voice coil. The other one is completely silent, as it should be. I've emailed the shop to inquire about a replacement, but knowing my luck it'll get caught in the Christmas mail & won't come until next year!
Nick at Blue Planet is sending me a replacement W8-670C & isn't even asking for the faulty one back, because the cost of shipping it back would defeat the point 🙂
bjorno - I'll have to read up on hornresp to have any idea what any of that means, but am I right in thinking from the comment that that's a 40l enclosure?!
bjorno - I'll have to read up on hornresp to have any idea what any of that means, but am I right in thinking from the comment that that's a 40l enclosure?!
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I tried to simulate the sub with winisd. I got 16l ported tuned to ~45 Hz, f3 is around 45 Hz. Does this sound ok?
I know that I can't get too low response with small size but this is almost the biggest box I can make.
I know that I can't get too low response with small size but this is almost the biggest box I can make.
Also I know this is a sub section but can someone check if I designed the satellites correctly. I got around 3 liter box BR tuned to 92 Hz, f3 is around 85 Hz. I tried to design a square port and I am not sure if I understood it correctly.
The first attached image is from winisd. Blue is the satellites and red the sub.
The second is a sketch for the satellites. Sorry for the bad picture and hard to figure out dimensions.. 🙂 . The dimension for the inside volume are 93 mm x 120 mm x 270 mm. 93mm comes from ready cut wood that I could use and looks nice.
The port dimension should 93 mm x 10 mm for the area and 8,4 mm for the length (part of the length comes from the baffle that is around 2 cm thick.). I couldn't calculate exact outer dimension because I am not sure yet on what materials I have available.
The first attached image is from winisd. Blue is the satellites and red the sub.
The second is a sketch for the satellites. Sorry for the bad picture and hard to figure out dimensions.. 🙂 . The dimension for the inside volume are 93 mm x 120 mm x 270 mm. 93mm comes from ready cut wood that I could use and looks nice.
The port dimension should 93 mm x 10 mm for the area and 8,4 mm for the length (part of the length comes from the baffle that is around 2 cm thick.). I couldn't calculate exact outer dimension because I am not sure yet on what materials I have available.
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