| keyser |
hi guys! (and girls, if there are any;) )
i plan to build a subwoofer. however, i am not sure if it would make an improvement in my music-only system! My main speakers already go pretty deep. there is still usefull output below 35 hertz. do you guys think a subwoofer would improve my music?
also: what is your view of the obove mentioned subject.
("when does using a subwoofer make sense in a music-only setup?")
all replies are welcome!!:smash: :smash: :smash: !! |
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| simon5 |
For me, a subwoofer in a music-only setup is absolutely necessary. It always depend on what type of music you listen.
Hip-hop, rap, techno, you need a sub.
For example: Lil Jon & Ying Yang Twins - Get Low
For example: DJ Tiësto - Battleship Grey
These tracks contains information at ~20 Hz.
You also need a sub for some metal, heavy metal, rock songs.
For example: Pink Floyd - Speak to me
That track contains information at ~20 Hz.
Any THX bass tests contains information at ~20 Hz.
You even need a sub for classical recordings! (organs, battle drums and such)
I have a Klipsch ProMedia 5.1 Ultra set and even with the sub which contains dual 8" flat to 30 Hz in-room and good extension at 25 Hz, it doesn't look good in these tracks, the sub is crying, overexcursioning, farting the whole time at high volumes.
That's why I'm currently building a sub that will be flat in-room to 15 Hz so I can play everything on it. |
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| BillFitzmaurice |
| Prior to Henry Kloss marketing the sub/satellite concept a couple of decades back there was no such thing as a subwoofer, and somehow we managed without them for 60 odd years. For pure music response to 35 Hz is quite adequate, though lower doesn't hurt. For HT going to 25 Hz will generally do it. |
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| simon5 |
But then you look at high end stuff in that era, like Klipschorn, 104 dB/1W/1m efficiency and flat to 33 Hz fully horn loaded with a big 15 inches woofer rated at 100W RMS capable of 121 dB SPL in-room... that means at 20-25 Hz it still had adequate power...
We get more bass in new music than before, also you can experience organ bass in your home with a big subwoofer, something that you couldn't before... |
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| tiroth |
| quote: | Originally posted by BillFitzmaurice
Prior to Henry Kloss marketing the sub/satellite concept a couple of decades back there was no such thing as a subwoofer, and somehow we managed without them for 60 odd years. For pure music response to 35 Hz is quite adequate, though lower doesn't hurt. |
Of course, most subs barely make it this far anyway, so it seems unsuprising that one could do without one. ;)
You could look at this and say they are unnecessary, or you could look at it this way: for a sub to be worth having, it better get down really low and/or relieve the strain on the midwoofer. I think there could be some mileage in using lighter, more responsive midwoofs down to 50-100Hz and allowing the subs to take on the high excursion material south of there.
As usual, best approached as a system rather than shoehorning another transducer to cover a narrow 10-20 Hz window. My feeling is that approach gets you less coherence w/o much gain in extension.
If you look at megabuck systems, a lot are 4-ways which essentially have integrated stereo subs. |
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| SY |
Like tiroth, my experience with subwoofing is confined to true infrabass-capable boxes- big and expensive. But the gain in naturalness is addictive; there may not be much music down there, but the phase behavior where there IS music is much improved.
And in my last two cone/box systems, I did essentially what he suggested: big old thangs (like JBL 2245H) running from 60-70 Hz down, high quality mid-size deals (like Dynaudio 17W-75) running the next couple of octaves. It makes integration a bit more complex, but actually easier to pull off. |
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| morbo |
For me it is essential at higher volumes with the music I listen to, which has a good deal of sub-35hz content. IMHO for loud listening of bass heavy music in general, you need to either:
1. have a dedicated low frequency reproducer (whether this is a sub or the woofer in a 3way) or
2. filter out some or all of the low bass.
I would not be happy with most 2ways for loud rock, orchestral, or electronic music, not because the bass is deficient, but because the midrange usually gets very sloppy when trying to do lots of bass. |
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| HeatMiser |
| Another reason to have a sub for music (or anything) is that, depending on your room, your main speakers might go plenty low but the best placement for imaging etc. isn't necessarily the best placement for delivering bass to your listening position. If you have a sub crossed over low enough, you can put it wherever it sounds best and leave your mains where they sound best. |
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| burnedfingers |
My ideas of the usage of subwoofers are to increase the low frequency to a point that is natural/normal. Secondly, to remove the subwoofer frequency from the main speakers to increase the efficiency and avoid duplication.
Sy mentioned running from 60-70 hZ down which is the way things are supposed to be set up. Too high a crossover point and your system sounds like ****. The frequency of 60-70 HZ is chosen in all good commercial systems because it is non-directional in nature and therefore the subwoofer doesn't become a point source.
Personally, I like my EVX 180's tuned 4th order with a 2nd order electronic filter. Big box big sound. |
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| adason |
well it depends
first of all what kind of subwoofer are you talking about?
there are those shi$# ones which have 5" to 8" sort of woofers made in china not worthy $5 which are good just for farting and burping (b@se)
and there are those worthy $5k, which have 15" to 18" woofers, or even 24" like cabase, which will improve any system
i think it is a matter of personal preference
someone can have electrostats and prefere coherent midrange
and will happily sacrify the bass
someone else will support them with abequate subwoofer
if you have excelent minimonitors, you should consider subwoofer
if you have excelent florstanding speakers which go all the way down, why bother
rather spend money on music |
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| RobWells |
I listen to a lot of electronic music, and cross my mains to my subs at 40Hz. Without the subs it sounds very weak.
Maybe less so with rock, jazz or acoustic (I have loads of rock and blues and acoustic stuff, and a fair bit of be-bop too). But for my system and my ~main~ music yes a sub is essential.
(subs are flat to 15Hz btw, with twin 10's per side from 40 to 250Hz )
Crossing higher highlights the quality difference between my tempest subs and scan-speak bass units aswell, if that helps. Below 40 I can't really hear the difference. (I've had the s-speaks flat to 20 in room and there is no loss in quality switching to the tempests below 40 compared to the s-speaks on thier own) The main difference there is max output levels.
BillFitzmaurice :
In my system I can roll off the bass at 35Hz at either 24dB/oct to resemble vented, or 12dB/oct at 35Hz to resemble sealed system. (I use digital xo) I can definitely hear the loss of bass on nearly everything (including TV) so I'm staying with subs:)
I'd imagine 'back in the day' they would not have had the equipment / inclination to do much big bass stuff. ie no synthesisers to push out all the low Hz info..
Cheers,
Rob |
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| adason |
| quote: | | I'd imagine 'back in the day' they would not have had the equipment / inclination to do much big bass stuff. ie no synthesisers to push out all the low Hz info.. |
back in the day we mostly listen to records and you know turntable is always prone to mechanical feedback, even if you have high end table with vacuum, having a subwoofer going all the way down to arms resonance is not a good thing
we got rid of that with cds but for what price? convenience for sound quality |
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| chris ma |
For now my setup is for music only. I agreed with most of the comments prior. But to me there is one point I like to make is that I like to litsen to moderate SPL no more than 93DB peak from my listen chair. With the subs cross from 60Hz down I can enjoy really good bass without being shout at by the mid and top range you normally do when pushing louder in order to get the bass. Everything balance out. Especially jazz, without the subs you would be missing a lot of double bass player's fancy moves! or you may not even know he was there with the band all along:)
just my 2 pennies..
The Butcher |
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| RobWells |
| quote: | Originally posted by adason
back in the day we mostly listen to records and you know turntable is always prone to mechanical feedback, even if you have high end table with vacuum, having a subwoofer going all the way down to arms resonance is not a good thing
we got rid of that with cds but for what price? convenience for sound quality |
I do most listening on vinyl. My subs are sealed - isn't that safer than ported if you're not using a rumble filter (I don't) ?
Also my deck is in a small room off the listening room.
Cheers,
Rob |
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| keyser |
thanks alot guys! (and ofcourse the girls, if there are any:) )
i don't know how to quote, so: i copied an pasted the text below:confused:
quote:
Originally posted by adason
back in the day we mostly listen to records and you know turntable is always prone to mechanical feedback, even if you have high end table with vacuum, having a subwoofer going all the way down to arms resonance is not a good thing
we got rid of that with cds but for what price? convenience for sound quality
I do most listening on vinyl. My subs are sealed - isn't that safer than ported if you're not using a rumble filter (I don't) ?
Also my deck is in a small room off the listening room.
Cheers,
Rob
right!
what does "conveniece for sound quality mean"?
ofcourse there are other places to discuss this, but technically speaking, 'cd-sound' offers you more quality!
in your ears the distortion that accompanies record-playback may sound good, but that does not mean it is better quality! it is not my intention to start a discussion about this. i just know (almost;)) for a fact that cd-quality is almost as good as you might ever need. vinyl is of lesser quality when it comes to reproducing the sound of the master-tape.
also: the difference in sound-quality between any good designed ampifier or cd-player is nihil!
i've gotten pretty far off the topic (i started myself:smash: )
if anyone would like to discuss this subject some more, we could start another thread somewhere else on this site. please give me a sign if any of you would.
I have a pair (german, about $2500)of Canton RC-L's. they both have 2 8" woofers. i think bass is pretty linear till about 40 hz. i listen to al kinds of music. Now i am planning to build a subwoofer with two visaton woofers:
http://www.visaton.de/deutsch/artikel/art_477_1_19.html
Would a subwoofer with 2 of these woofers be good with my speakers? i personally have no idea. at what frequensie should i let the sub play along?
some specs. are at www.thielesmall.com:
http://thielesmall.com/database.asp
(the visaton W 300 S is a 12"woofer)
cheers guys! |
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| Pan2 |
"it is not my intention to start a discussion about this. i just know (almost;)) for a fact that cd-quality is almost as good as you might ever need. vinyl is of lesser quality when it comes to reproducing the sound of the master-tape.
also: the difference in sound-quality between any good designed ampifier or cd-player is nihil!"
/Peter |
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| chris ma |
| quote: | Originally posted by Pan
"it is not my intention to start a discussion about this. i just know (almost;)) for a fact that cd-quality is almost as good as you might ever need. vinyl is of lesser quality when it comes to reproducing the sound of the master-tape.
also: the difference in sound-quality between any good designed ampifier or cd-player is nihil!"
/Peter |
Wow, i think thats a rather taller order that you just stated! I am most curious as what facts you get from what you have just stated when reproducing sound!!! |
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| tiroth |
| Let's not get distracted from the matter at hand. We're heading into religious war territory with CD vs. vinyl. We can accept each others opinions here and just talk subs, right? |
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| jdybnis |
| I agree with tiroth. This isn't the place for that kind of "discussion". If that's what gets you off go pick a fight on AA, not here. Actually keyser, I assume that picking a fight wasn't your intent. But dropping a "CD's are better" tirade just because someone mentions vinyl is about the same thing. In anycase it is rude behavior, even on the internet. |
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| keyser |
you're right. i'm sorry...
back to subs then |
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| adason |
yes, lets get back to the subwoofers
dont take me wrong that I dont like subwoofers
I do, I have a couple of them
my first diy sub was 2 x 15" woofers (350watts continuous each, 97 dB sensitivity, dont remember brand) in isobarick configuration in closed box, rather large closed box, as you know folks, isobarick requires 1/2 volume for the same low frequency cut off
that sub was going flat to 20 Hz after equalization ( I use boehringer ultracurve 31 band digital)
even 12.5 Hz was capable, except my SPL meter was off a lot, you could see membranes going back and forth an inch! hard to say if you could hear anything, but certainly feel a belly dancing!
later I upgraded to 18" cervin vega and built my sub into the wall of attic, so it became integral part of the house, now it realy has infinite volume and performs even better, handles
now I normaly listen at moderate levels (80-100 dB) but at certain time after significant consumtion with good company we want to crank it up a little, and then the lps are out, only cds
thats why i mentioned mechanical feedback, ok? not a problem at normal levels, but always there after certain level, unless you move turntable to other sound proof room |
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| adason |
| quote: | | what does "conveniece for sound quality mean"? ofcourse there are other places to discuss this, but technically speaking, 'cd-sound' offers you more quality! in your ears the distortion that accompanies record-playback may sound good, but that does not mean it is better quality! it is not my intention to start a discussion about this. i just know (almost ) for a fact that cd-quality is almost as good as you might ever need. vinyl is of lesser quality when it comes to reproducing the sound of the master-tape. |
well, what I ment "convenience for sound quality" is when people replace something like reel to reel for cassette deck, the convenienece of the media got better, but the sound quality got worse
even the most expensive cassette deck will not even come close to the reel to reel
the same happened with lps and cds, cds are much more convenient to handle, but sound inferior
you think that lps sound worse than cds because you are not comparing adequate lp setup
in my case i have california audio labs cd player, which is quite a good one, selected it for analog like sound, but is is only $500 cd player, does not even close to lps, for I spent on cartridge itself more than that
when i performed blind test on my friends and played both at the same time with matching volume, they always went for lp as a winner
but this is probably for another topic |
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| morbo |
| quote: | | the same happened with lps and cds, cds are much more convenient to handle, but sound inferior |
Stating this as if it were a universally accepted fact without an IMO or, more appropriately, IMHO, is a great way to start a flame war IMO. Is that what you're aiming for? |
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| keyser |
first of all, i don't mean to offend anyone...
i wouldn't name a discussion like this one a war either! however, i'd like to continue the discussion on this topic about audible differences between several music storing formats and equipment. but ofcourse this is not the right place. if any of you is also interested, we could start another thread somewhere else on this site. I will now make a few statements. this is just how i see "the truth". Better will mean, more faithfull to the original recording. more hi-fi.
so, IMHO(!):
* cd-sound is better than lp-sound
* all properly designed cd-players sound the same
* all properly designed amplifiers sound the samen (if not driven into clipping)
* if your equipment and cables are properly designed, the soundquality you get in your room depends on 3 things:
-quality of the recording
-quality of the loudspeaker-system
-acoustics in the room
i am sure most of you will disagree with one or maybe all points. please tell me, and we could start another thread. |
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| SY |
| Yes, if you want to discuss CDs versus vinyl, a separate thread would be much better. But in all honesty, I think it's a subject that's been beaten to death. And is largely moot in this day and age. |
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| keyser |
| "People like to feel themselves to be rebels against some powerful repressive force — as long as they are sure it is quite safe." -Isaac Asimov |
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| morbo |
*EDIT SY - thank you for that quote! I love Asimov, and the quote is my new email signature.
thanks for pointing that out Audiofreak |
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| AudioFreak |
morbo,
it's not actually keyser's quote, it came direct from SY's signature. |
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| Pan2 |
keyser,
(makes me think of that movie with the legend "keyser soze")
While I agree that the most important in music reproduction is;
-quality of the recording
-quality of the loudspeaker-system
-acoustics in the room
I must say that;
* all properly designed cd-players sound the same
* all properly designed amplifiers sound the samen (if not driven into clipping)
is as far from the truth as possibly could be.
/Peter
ok, ok let´s not get more of topic! sorry! :) |
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| keyser |
you're right pan, about where i got my nickname from. you're wrong about the other thing. This will be the last time i polute this thread with info that is not relevant as far as the threads subject is concerned. just like you to check ou these sites.
http://sound.westhost.com/
and the next is from the former director of acoustic research at McIntosh Laboratory
http://www.roger-russell.com/truth/truth.htm
you could also google up double-blind test and hifi or sound reproduction (something...)
everybody can relax, i'm goin back to subwoofers |
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| tiroth |
| quote: | Originally posted by keyser
you could also google up double-blind test and hifi or sound reproduction (something...)
everybody can relax, i'm goin back to subwoofers |
And like that...he was gone. |
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| adason |
| quote: | | Stating this as if it were a universally accepted fact without an IMO or, more appropriately, IMHO, is a great way to start a flame war IMO. Is that what you're aiming for? |
definitely not, no need to start another futile discussion like tubes vs solid state (we know the unswer anyway)
just one more thing about subwoofers for keyser who started it all before i go
if you are about to built a sub, make it a good one
your speakers have already two 8" woofers per side, and relatively good bass extension
I am affraid one 12" woofer will not be adequate subwoofer for them, I suggest if you are already investing money and time into woodwork, go with 15" or possibly bigger woofers, does not cost that much more, important parameter besides low frequency extension is efficiency, the higher the better, aim for 97 dB/w/m and higher
I hope you will find woofer so you will not be dissapointed when you finish it
good luck! |
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| keyser |
tanx adason
what do you think about two 12" woofers. i'm thinking about using a pair of Visaton W 300 S:
check for 12"woofer from visaton at:
http://thielesmall.com/database.asp
i'm thinking about using them with a conrad subwoofer-module. this module works like a REL-module: it is supposed to be used to support sub-bass (below about 50 hertz) instead of reproducing mid-bass (from 50 hertz upwards). With this module the subwoofer should be placed in parallel with the main speakers. There's no high-pass. The low-pass has to be adjusted with only frequensie and gain to be integrated with the main speakers.
as i said before, my mains go pretty low already. the cross-over will probably be at around 30-35 hertz.
what do you think? |
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| tiroth |
| quote: | Originally posted by adason
I am affraid one 12" woofer will not be adequate subwoofer for them, |
If your mains go down to 35Hz, then a couple of 12s are probably not going to help that much in terms of extension. It'll help a little, but do some modeling. Those Visatons have a Fs of ~30Hz, so you'll need to go ported or play with the response (hi pass/transform/BFD/etc) to get any extension at all over your current setup. Most 12's F3s are in the high 30s sealed, and this is the theoretical--in reality, they have rolled off even more this low! Room gain helps, but use your current mains as a guide to how much you'll get.
Or HP your mains and use the subs to give you higher max SPL instead of extension, which could certainly improve the bass impact.
Believe me, I'm in your boat with my current mains, Proac 2.5. They don't go down quite as far, maybe 42Hz in room, but I still don't get a lot of mileage out of a single sealed shiva (12"). |
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| keyser |
[QUOTE]Originally posted by tiroth
[B]
Those Visatons have a Fs of ~30Hz
ik think you looked at the W 300, not the W 300 S. it has a Fs of 22 hertz. think that their extension in a good box should be similar to a shiva's. i know the ProAc Response 2.5 pretty well, because a good friend of mine has them, very nice speaker! he supports them with a Backes&Muller subwoofer. this U-sub 2 has two 2" woofers, and extension is a lot lower than the still admirable bass-extension of the two way proacs. Do you think such deep bass is generated with use of an equalizer?
I've never heard a shiva, but it is said that they go pretty low! almost everybody on this forum raves about those units. Do you think is has an F3 in the high 30 hertz? |
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| adason |
the visatons 300S looks ok to me, two woofers is better than one, the biger and stiffer the box the better too, if you insist on 12" woofers i personaly have heard good reviews about nht 1259 (fs 16.5 Hz!), handles plenty of power, goes deep, cost a lot though
http://www.madisound.com/nht1259.html
| quote: | | as i said before, my mains go pretty low already. the cross-over will probably be at around 30-35 hertz. |
i guess to cross the sub at such a low crossover point is a mistake, you will not hear much out of it, so sub will have no purpose than
cross it higher, you can experiment from 80, 100, up to 150 Hz, the higher you cross the sub, the more critical the slope of crossover and placement of the sub
one thing you should consider is to limit the low frequencies from your main speakers (run them from 150 Hz up), once you will have the subwoofer
any midrange/woofer will sound better in midrange area if its free from duties as woofer, you will hear midrange much cleaner, with lower distortion, and that i believe will be the best benefit of subwoofer for its a midrange where will live, if you dont get midrange right, who cares about the subwoofer
i know nothing about your hifi besides it is 2 channel music system, it should not be that hard to split the signal at 150 Hz and use your main amplifier for two main tower speakers and dedicated subwoofer amplifier for sub (the same aplies for amplifiers, your main amplifier will be happy when freed from low fr. duties)
i still believe you should step up to 15" and bigger woofers, the most important being fs and efficiency
adason out |
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| RobWells |
For music, with stereo subs the highest I would consider crossing is 80Hz. With a single sub I'd stick to 40HZ.
Keyser, is the 35Hz for your mains 'on paper' or measured in room ?
Cheers,
Rob
Edit, just searched for your mains, but couldn't find an english review. However, with twin 8" per side I'd guess you can safely cross low without ' damaging' your midrange. |
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| simon5 |
| Not a good idea IMHO to cross at 150 Hz, you get better midrange maybe but you have awful localisation problems! |
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| keyser |
i have the two visatons already. what do you think simon? how should i build a subwoofer around them?
i am also thinking about a REL kind of setup: the subwoofer starting below the natural roll-off of the main speakers.
my speakers are Canton RC-L
this is what canton sais:
Leistungseigenschaften:
- Stand-Lautsprecher
- aktive Ba-Entzerrung
- 3-Wege-Lautsprechersystem
- Bareflex-System
- Wirkungsgrad/Schalldruck 1W/1m: 89 dB
- min. Impedanz: 4 Ohm
- max. Impedanz: 8 Ohm
- 200 W Nenn-Belastbarkeit
- 350 W Musik-Belastbarkeit
- Frequenzgang-Untergrenze: 18 Hz
- Frequenzgang-Obergrenze: 30000 Hz
- bergangsfrequenz Tief-Mittelton: 300 Hz
- bergangsfrequenz Mittel-Hochton: 3500 Hz
- 2 Tieftner
- 1 Mitteltner
- 1 Hochtner
- Durchmesser Tieftner: 22 cm
- Durchmesser Mitteltner: 18 cm
- Durchmesser Hochtner: 2,5 cm
Gehuse-Eigenschaften:
- Breite: 26 cm
- Hhe: 110 cm
- Tiefe: 34,7 cm
however, frequenzgang-untergrenze is not 18 herz lineaer! think the F3 will be around 30-40 hertz. i may be wrong ofcourse! my room is not very large (5 x 4 meters). the subwoofer doesn't have to give me more SPL's, just the deep notes. would the visatons do, or should i try to get rid of them through ebay or such? |
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| simon5 |
| If these Visatons really have a Fs of 22 Hz, you can make a good sub with them. With a big ported box, you'll be able to get flat response down to 20 Hz with usable bass down to 18 Hz approx IMHO. |
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| tiroth |
Well, if you already have them, that is something different. MDF is cheap, so it is worth building some boxes to try them out. :)
Another alternative would be to stuff your ports and gain more usable range for the sub. You've said SPL isn't an issue, but after working hard for max extension I am now wondering myself if it isn't a good idea to consider max SPL more at these low frequencies.
Shiva 90L sealed F3 is 31Hz. |
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| simon5 |
| Yes but Shiva ported in a EBS 142.5 liters need only one sheet of 4' x 8' and get a anechoic F3 17.8 Hz. |
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| keyser |
thanks guys!
a friend of mine put the parameters of the visaton in LspCAD. de program suggested twin boxes of 138 liters, ported at 25.4 hertz.
i don't know the F3. could someone estimate the F3 with these values i gave above?
i guess this should give me reasonably deep bass, won't it? The box sure will be large, but i don't really mind. for all of you to know which woofer we are talking about, i've pasted some info from www.thielesmall.com below:
Brand Visaton
Model W 300 S 8 Ohm
Description
Range / type Woofer,
Typical use Undetermined
Recomended enclosure
Series
Manufacturer
Order nr 9041
Production status Active 2004
Nom. diamerer [inch] 12
Vas [Liters] 340
Qts 0,32
Qes 0,39
Qms 1,8
Fs [Hz] 22
Sensitivity [dB] 92
Max Power [W] 150
Power definition 150 RMS, 200 max
Lower freq [Hz] 22
Upper freq [Hz] 1000
Rec. Filter freq [Hz]
xmax [mm] 14
Moving mass [g] 57
Disp area [m2] 0,0507
Disp Vol [cm3]
xdamage [mm]
Air gap [mm] 8
Coil height [mm] 18,5
Coil diameter [mm] 50
Cms [mm/N]
Rms [N*s/m]
Magnet weight [gr]
Magnet height [mm] 0
Magnet diameter [mm] 140
Magnet material -
Re [ohm] 6,6
Z [ohm] 8
L [mH] 1,8
Bl [Tm] 11
Magnetic flux [Wb] 1,4
Flux density [T] 1,1
Outer diam. [mm] 332
Bolt circle [mm]
Nr of bolts [Nr]
Cutout [mm] 280
Weight [Kg] 4,5
Height [mm]
Depth [mm] 134 |
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| keyser |
My friend's program suggested to use 17.8cm of the the 10.4 cm diameter PVC-pipe i had lying around. according to the formula i found on www.diysubwoofers.org the length of the port should be 21 centimeters! why do these values not correspond?
www.diysubwoofers.org :
Lv = (23562.5*Dv^2*Np/(Fb^2*Vb))-(k*Dv)
where,
Dv = port diameter (cm)
Fb = tuning frequency (Hz)
Vb = net volume (litres)
Lv = length of each port (cm)
Np = number of ports
k = end correction (normally 0.732) |
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| simon5 |
You couldn't tune that lower than 25 Hz ?
The Shiva with a Fs of 21 Hz is tuned at 18.1 Hz with a 142.5 liters box. |
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| adason |
| quote: | | Not a good idea IMHO to cross at 150 Hz, you get better midrange maybe but you have awful localisation problems! |
i absolutely agree
thats why i wrote the higher the crossover frequency, the steeper it should be, and more carefull the sub placement
if placed right next to the main speakers, no problem whatsoever no matter what crossover frequency
i have copy of someones phD thesis on subwoofers/satelites and localization issues, the ideal crossover frequency is 150 Hz assuming correct sub placement
it is logical to place sub as close to main speakers, make no sence to put it behind your back, no matter how low you cross it
there are not only localization issues but phase issus as well, therefore the best placement is as close to mains
the benefit of crossing higher (assuming correct sub placement) is releaving main speakers from low frequencies thus lower midrange distortion, higher spl for dedicated woofer can handle much more power...i tried all different combinations, this is the one which worked best for me: after the volume control split the signal at 150 Hz, use low power preferebly single ended classA amp for satelites, dedicated high current sub amp with selectable crossover fr. and volume for sub, play with those two setting till the sub disappears and bass becomes integrated with mains |
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| keyser |
i intend to make a subwoofer in the REL manner. connecting the sub at speakerlevel to the poweramp. REL subwoofers have no high pass, as the main speakers are not supposed to be relieved from the bass. the subwoofer should only take over from where the natural roll off of the speaker starts.
how could i tune the box for the sub to be more efficient at the lowest frequensies. this may be at the expense of sensitivity at higher frequensies.
what happens in general when you make the box larger?
and what generally happens when you change the length and diameter of the reflex-pipe?
how do you determine what frequensie the port should be tuned at? |
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| simon5 |
A larger box give better low frequency response.
A longer port in a given box will tune the box lower, so better low frequency response.
A larger port is needed for larger subs.
You tune the port according to what you want your sub sounds like.
You tune around Fs for compromise between low frequency response and high sensivity in the 30 Hz range, it's also a compromise between flat response and boomy response.
Higher than Fs will give higher sensivity and poor low frequency response, it will be boomy.
Lower than Fs will give lower sensivity, but maximum flatness in room response and good low frequency response. You can't go too low, or your frequency response curve will look ugly. You'll have a point between Fs and the tuning of the port where the bass response will be poor. |
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