| Jim McPherson |
I've tried modeling the Tangband W8-1363SA neo sub and have had very little success. I'm trying to build a small sub to compliment a "zaph" Hi-Vi B3S system.
Has anybody else used this sub with good results?
Parts Express W8-1363SA Webpage |
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| sreten |
Hi,
4 to 6 litres sealed, will need an amp with bass boost.
or
8 to 12 litres vented tuning around 33Hz, as the volume
is so small you will need to use a 10" passive radiator.
:)/sreten. |
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| Jim McPherson |
Not trying to fool mother nature... just want to know if anyone has had success building an enclosure that takes full advantage of what this speaker is capable of.... but thanks for the helpful post.
-Jim |
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| GM |
Greets!
You're welcome!
Well, this is the subwoofer forum and you said you want a small one, which per the article is an oxymoron so it seemed the appropriate observation, but as always YMMV. ;)
Anyway, for acceptable small room/'intimate' seating LF/midbass performance, sreten's alignments should work fine for music if the published specs are reasonably accurate, but to get the most out of it overall will require a large pipe horn, preferably corner loaded.
GM |
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| sreten |
| quote: | Originally posted by GM
.......Well, this is the subwoofer forum and you said you
want a small one, which per the article is an oxymoron.......
GM |
Hi,
No its not an oxymoron, you trade amplifier power for box size.
Note that max volume in the low bass = cone area x excursion,
max volume in the upper bass = sensitivity x amplifier power.
In this case c/o is to two B3S fullrangers so upper bass level
required is very modest, therefore the sub can be small.
For this purpose you need a low sensitivity driver, this means
for the bass extension the sub will be small. Low sensitivity and
high excursion also means it can sink the sub amplifier power.
A higher sensitivity unit needs a larger box and less
amplifier power for the same performance as the above.
IMO with a PR and plenty of juice (150W) its a near ideal unit for purpose.
:)/sreten. |
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| mashaffer |
Maybe it is a matter of perspective. To me anything 1ft^3 or less is pretty darned small. My mod of this driver indicates that we can get down to 30Hz with a slight EBS alignment with about 6/10 of a cubic footh and about 11" long port of 1.75". Now you would have to be a little bit careful about designing for a port that long but it seems like it could be done. It seems like going much lower would be difficult for any 8" driver.
mike |
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| Jim McPherson |
Thanks for the suggestions!
On the PR, I think I'd need at least 2 of the Dayton 10'' PR's or one 12'' to get me the kind of excusion that I'd need to match the 12mm Xmax of the W8-1363SA. That would take up a lot of real-estate and force a larger box that I want to use.
What do you think about a Linkwitz Transform circuit that gets me an F3 of 30Hz? I'm worried about port noise on the ported options, and a large port to get rid of the noise ends up being unmanageably long.
If I have a moderate power LT circuit and use a 250 watt plate amp, I think that I can get some good performance out of this long excursion "sub".
-Jim |
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| jamikl |
Perhaps the long port could be used as part of a speaker stand if this is needed?
jamikl |
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| sreten |
| quote: | Originally posted by Jim McPherson
What do you think about a Linkwitz Transform circuit that gets me an F3 of 30Hz? I'm worried about port noise on the ported options, and a large port to get rid of the noise ends up being unmanageably long.
If I have a moderate power LT circuit and use a 250 watt plate amp, I think that I can get some good performance out of this long excursion "sub".
-Jim |
Hi,
Strictly speaking we are not discussing a Linkwitz Transform, just simple bass boost, which is available on several plate amplifiers.
:)/sreten. |
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| Jim McPherson |
Mine does have the option to add bass boost. I think I'll try it in a 6 litre box and try 5db of bass boost at 30Hz.
If that doesn't work, I'll try a larger box with a PR.
-Jim |
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| GM |
| quote: | Originally posted by sreten
No its not an oxymoron, you trade amplifier power for box size.
In this case c/o is to two B3S fullrangers so upper bass level
required is very modest, therefore the sub can be small. |
Greets!
Yes, you're technically correct, but the reality is that there's no drivers capable of handling the 10+kW required to make useful output below 20 Hz in a small box, much less without audible thermal power compression, so for now it's an oxymoron.
The woofer, not 'sub', can be small because of the reasons you list. Whether it can sink the power without audible thermal power compression remains to be seen. I know the one in my computer system certainly won't. Typically, a driver begins power compression at a fraction of its rated power (1/4-1/2), though some recent bona fide sub drivers do somewhat better.
Call me old fashioned, but just because B*** got the industry at large to mislabel any relatively long throw woofer a subwoofer doesn't make it one.
GM |
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| GM |
| quote: | Originally posted by Jim McPherson
On the PR, I think I'd need at least 2 of the Dayton 10'' PR's.......
What do you think about a Linkwitz Transform circuit that gets me an F3 of 30Hz? I'm worried about port noise on the ported options......... |
Greets!
The Dayton 10" PR can handle ~100 gr more than needed to tune an 11 L net cab to 30 Hz, so one is fine, though it will need to be either massive or anchored somehow if the PR is driven hard.
Ports can be flared or damped to reduce vent mach, but yeah, venting will increase the net cab size a sizable percentage.
The LT would be the better choice if there's some room gain and negligible thermal power compression, but at this price point the latter is probably just wishful thinking.
GM |
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| GM |
| quote: | Originally posted by jamikl
Perhaps the long port could be used as part of a speaker stand if this is needed?
jamikl |
Greets!
Yeah, this is a good way to go with some monitor speakers, but this so-called 'sub' needs all the boundary gain it can get.
GM |
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| sreten |
| quote: | Originally posted by GM
Greets!
Yes, you're technically correct, but the reality is that there's no drivers capable of handling the 10+kW required to make useful output below 20 Hz in a small box, much less without audible thermal power compression, so for now it's an oxymoron.
The woofer, not 'sub', can be small because of the reasons you list. Whether it can sink the power without audible thermal power compression remains to be seen. I know the one in my computer system certainly won't. Typically, a driver begins power compression at a fraction of its rated power (1/4-1/2), though some recent bona fide sub drivers do somewhat better.
Call me old fashioned, but just because B*** got the industry at large to mislabel any relatively long throw woofer a subwoofer doesn't make it one.
GM |
Hi,
with a pair of B3Ss to mate to (cannot be used below 100Hz)
we are talking the man on the streets definition of a sub, not
a serious hi-fi fans perception of extremely low bass.
You are essentially correct, in the above context 20Hz as a
target is pointless. IMO a room cutoff of around 30Hz is more
realistic, and given the excursion limited output of the driver,
maximum use of room gain and positioning will be needed
to get to this point with any sort of reasonable level.
IMO the small sealed TB with bass boost is a "subwoofer"
if you compare its capabilities to the usual tat labelled
as a subwoofer that comes with HT systems.
:)/sreten. |
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| troystg |
I am contemplating using 4 of those woofers in a vehicle to augment the a/d/s/ front end. Small sealed cabinet, Orion 2125SX amp and cabin gain should do the trick nicely.
6 liters sealed... Man I hope I can manage the space. :D :bawling: :clown: |
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| audiosteve |
I was thinking about using this same woofer with either the same satellites or a pair of TB W3-871S based speakers (Orphans).
This is a problematic woofer. Not nearly the LF extension I had expected when first looking at the FS and the Xmax. Serves me right for not modeling it before I ordered. (it's in the mail now)
The only alignment I could come up with that was reasonably flat and reasonably low w/o boost is as follows:
8 liter box
2" dia. port 15" long.
This would yield an F3 around 43 Hz. Which for listening to music in my office is not too shabby. It would never make a good home theater set up but I am sure will sound great on music. Realistically, there isn't a lot of content even as low as 43 Hz on most music made with conventional instruments and it will yield a more compact and wider range system than a comparable bookshelf system. 95% of the time that last low octave will never be missed.
The mains amp is a Trends TA-10 and sub amp is a Dayton SA100.
Should sound good. The only thing that scares me is the 15" port length. Anyone have any experience with ports this long at this diameter?? Is this a non starter or will it work?? |
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| sreten |
| quote: | Originally posted by sreten
Hi,
4 to 6 litres sealed, will need an amp with bass boost.
or
8 to 12 litres vented tuning around 33Hz, as the volume
is so small you will need to use a 10" passive radiator.
:)/sreten. |
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| GM |
| quote: | Originally posted by audiosteve
Anyone have any experience with ports this long at this diameter?? Is this a non starter or will it work?? |
Greets!
Some. ;) A driver wants to 'feel' Vb = Vas, Fb = Fs, so tuning the cab a bit under-damped and stuffing the cab and vent as required damps both the pipe harmonics and any excessive Fb peaking. That said, since you didn't mention any size constraints, a bit larger ML-Voigt pipe ('BIB' horn with vent) stuffed to suit can push Fb a little lower with much more gain BW (all dims i.d.):
L = ~113"
CSA = ~70.14"
Zo = ~32.65"
4" dia. x 10" vent near/at the bottom
GM |
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| audiosteve |
Hi GM,
I am ignorant of the terms you used. What is a Voight or a BIB?javascript:smilie(':confused:')
confused
What is the list of items you gave?? I don't understand that nomenclature either.
Also, the design I gave does tune the box around 42 Hz which seems to model well. My primary question was will a 2" x 15" actually work or is it too long for some reason?? Or will I definitely need a passive radiator.
Can you please help me out with some clarifications to your post?
Thanks much,
Steve |
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| sreten |
Hi,
What shape box of ~ 10L takes a 15" pipe ?
http://www.diyaudio.com/forums/show...t=&pagenumber=3
| quote: |
Hi,
32ft/s = ~ 10m/s.
in WinISD Pro 10L box tuned to 38Hz, 34mm O by 160mm long port :
for 150W I get max port velocity = 96m/s (320ft/s) at 34Hz.
To peak at 11m/s you need a port 10cm in diameter and 1.5m long.
/sreten.
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:)/sreten. |
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| audiosteve |
Sreten,
I obviously don't know my may around Winisd yet. Your comments shed a lot of light on the issue for me. A passive radiator it is. The only problem with that is I can't find a commercially available unit that yields a flat response below 50Hz. The 10" from PartsExpress gets close, still a bit of a bump and an F3 at around 45Hz. The 8" looks great but stops at 50 Hz and has a lower Xmax than the driver. No great solution with either.
What I probably need to do is use the flat PR and then add some boost. Stupid me. I already ordered the amp and it doesn't have any boost available. I jumped too quick on this project w/o doing all the modeling I should have up front. javascript:smilie(':dead:')
dead
Thanks,
Steve |
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| GM |
Greets!
Sorry about that, it seemed reasonable to assume that someone who's been around awhile would have seen/read the many dozens of threads across the forums about TLs, MLTLs, Voigt pipes, how to use MJK's MathCad simming worksheets, etc., not to mention the humongous Bigger is Better (BIB) thread and its various spin-offs.
Anyway, I answered your primary Q and you can do forum searches to get 'up to speed' with all the rest if you're interested enough.
GM |
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| audiosteve |
A reasonable assumption about me being around for a while.
But although I registered for this site a few years back I haven't checked into the loudspeaker threads at all. And my past speaker building never took me into much in the way of low frequency design. I've always just done done flat sealed boxes. I am really quite the newbie with respect to LF design. I'll do a little more poking around on my own before asking any more questions that I now realize are pretty elementary to the rest of this forum. Thanks for your feedback. |
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