Placering af subwoofer

Hej alle..

Jeg har et lille problem..

Jeg har dette surroundsæt Pioneer S-V24-W.

Problemet er bare, at jeg gerne vil have, at min subwoofer skal stå under mit plasma, som hænger på væggen.

Men når jeg så sætter mig i sofaen kan jeg næsten ikke mærke bassen.

Er det fordi min sub er for lille?

Eller kan man indstille den på en eller anden måde.?

Man har jo altid hørt, at det er ligemeget hvor man sætter sin subwoofer..

Jeg kan se et problem og måske en delvis løsning.

Din subwoofer har en meget lille basenhed og hvis din stue er mere end "lille", så kan det være meget svær at spille den op. Jo større stue jo større enhed skal der til. Det handler om at flytte luft. Og det kan en lille enhed ikke rigtigt. Selv om den har det der hedder "lang vandring", dvs. at den kan flytte sig langt og stadig bevare et godt greb om membranen.

Men der er alligevel noget der kan hjælpe og det er placeringen. Du vil gerne sætte din sub under dit TV, sandsynligvis  syntes du det ser mest korrekt ud til din stue og det har du nok ret i.  Det ved du jo.

Men en højtaler spiller højere ved forskellige placeringer. Man måler lyd i DB og 3DB er en fordobling af lyden. Og placerer du nu en højtaler ude på gulvet vil den spille lavest af de andre placeringer der kunne tænkes. En enhed placeret på gulvet vil spille 3db højere, anbringes den op af en væg vil den forøge til 6db og endelig vil den i et hjørne spille helt op til 9db højere.

Men en højtaler er normalt konstrueret til at stå frit, dvs. ude på gulvet for at spille lineært, altså med en en ret frekvensgang. Så normalt er det så den bedste placering. (Mange der skubber en almindelig højtaler op af en væg får faktisk ikke en optimal gengivelse.)

Imidlertid kan en lille subwoofer måske ikke klare sig ret godt på dette sted så man er måske tvunget til at finde et andet sted. Anbringer man nu en stor subwoofer i et hjørne kan man få en buldrende bas som ikke lyder godt, men i dit tilfælde vil det måske gå an, da det er en meget lille enhed. Tror det er en 6,1/2" enhed du har.

Jeg ville prøve at experimentere lidt.

Ken_T

Subwoofers put the 'point one' into surround sound systems, refreshing low frequency parts that other speakers cannot reach. Integrating a subwoofer into your home cinema system is a tricky task, but you can do it, with a little help...

In home cinema speaker systems subwoofers are responsible for delivering bass from a dedicated low frequency effects (LFE) channel as well as supplementing low frequencies derived from other speakers that are simply too small to reproduce them.

Integrating a subwoofer into your system to produce a seamless sound is a challenge for any home cinema enthusiast. Experimentation is essential but using this four-step guide to subwoofer success will ensure sonic highs from the low frequency performance of your system.

B&W PV1

1. Subwoofer Placement
Although low frequency sounds are considered virtually non-directional, it's important to find a place in your listening room that allows your sub to perform to the best of its ability. No two rooms are the same and it takes a little experimenting to find your room's 'bass nodes', where your sub will sound best.

The simplest way of finding the best position is to begin by placing your sub in your usual listening position. Then, play a familiar soundtrack with a consistent bass line and move around your room listening for where the bass sounds best - you might have to get down on your knees since most subs tend to sit close to the floor. Experiment by moving closer or further away from walls, in corners etc until you find a place where the bass sounds smooth and extended without exaggeration or boom. And that's the ideal site for your sub.

Be aware that placing subs close to hard walls or floors will enhance low frequencies through reflections off the stiff surfaces, while allowing your sub some free space does the opposite. Corners are often suggested as ideal places as they act like horns to emphasise the sound, which is fine if you have a weak sub but can lead to distortion and loss of detail otherwise. No room dimensions are ideal and compromises will always have to be made according to both room acoustics and aesthetics.

Revel B12

2. Bass Management
In order to integrate your sub with the rest of the speakers in your system you'll need to access the bass management settings of your home cinema receiver. These allow you to determine speaker sizes and crossover settings that tell the receiver how to handle low frequency information, which is inherent to the success of your system's sound performance.

Speaker Size
Selecting speaker size offers a straightforward choice between Small and Large speakers, with anything up to the size of a bookshelf speaker considered small while large speakers are generally floorstanders that can produce a full flat range (20Hz-20kHz) of undistorted frequencies.

Setting your speakers to Small automatically redirects low frequencies to the sub at a predefined crossover point allowing small speakers to reproduce sounds in their frequency spectrum without straining while low frequencies are handled by the sub. With Large speakers you'll need to manually select a crossover point telling the receiver when to redirect low frequencies to the sub. If your system features a mix of speakers, say one using a pair of large front speakers accompanied by smaller surrounds and a centre, you'll need to set different speaker sizes accordingly.

Crossover
The crossover is the point at which low frequency sounds are redirected to the subwoofer while the frequencies above it continue to play through the other speakers.

Setting the crossover too low will produce a gap between frequencies produced by the sub and the speakers leaving sounds distorted or lost altogether. Setting the crossover too high however, forces the sub to create high frequency sounds which it isn't designed to reproduce, leading to a muddied sound overall. You'll need to refer to the user's manual to find the recommended settings for your particular sub but it's still worth experimenting with a range of crossovers as speaker bandwidth doesn't necessarily correspond to the dynamics of your room.

Try aiming for a crossover point that's around 10Hz above the lowest frequency that your smallest speakers can reproduce without distortion. This will vary depending on your speakers but you can use these figures as a guideline:

Satellite speakers 100 - 120Hz
Bookshelf speakers 60 - 100Hz
Floorstanding speakers 40 - 80Hz

A crossover point of 80Hz is seen as the recommended standard for most systems and is a good starting point. It's the same crossover used in all THX certified systems but needn't be taken as gospel and, once again, experimentation is the key.

A simple way to determine crossover is to completely open your sub's crossover filter so it is operating with a full bandwidth with no roll off. Then turn the volume level right down and play a track with plenty of bass, slowly adjusting the volume until it's at the same level as the rest of the track. Now, adjust the crossover filter until the sound increases in depth, but not volume. And that's your crossover point.

REL Storm 5

3. Phase Control
Phase control is a switch on your subwoofer that electrically reverses its polarity allowing sound waves to synch with those coming from your main speakers. It's especially useful if your receiver's sub output is electrically out of phase with speaker outputs.

Let your ears judge if the sound is out of phase - usually the difference is obvious, so if you can't hear it, chances are it's fine. If you're not sure then try reversing the polarity of connections to your main speakers. Play a bass-heavy soundtrack and adjust the phase until you can barely hear the bass and then reconnect your speakers properly. Your sub should now output optimum bass in phase.

4. Level control
Finally, you'll need to adjust the level of your sub so that it's operating at the same volume as your other speakers. You can attempt this by ear but if you want to be accurate, use your receiver's test tones together with a sound pressure level meter (SPL - around £30-£40).

To use an SPL, make sure the room is quiet and take a seat in your ideal listening position, then set the SPL to 80dB, select C weighting and slow response. Hold the SPL in front of you facing upwards and turn the volume of the test tone up until the SPL reads 75dB, then adjust each channel until you get the same reading. It's tempting to have it too loud (the most common mistake) but this will ultimately upset the whole balance of your system.

A perfectly integrated sub should solidly extend low frequencies and increase a sense of space without drawing attention to itself. Once you've got that, you're well on your way to home cinema sound.

Hej!

Har selv haft stor glæde og hjælp af dette...du kan jo prøve om det er brugbart.

lrev

Redigeret af lrev - 22-Januar-2007 kl. 08:58

http://www.recordere.dk/forum/forum_posts.asp?TID=18519& KW=xtz

Prøv at kaste et blik på denne....den sparker r..-og er tilmed BILLIG!

lrev

Tak for de gode "tilbud", men det skal være en Pioneer, som passer til systemet.

Tror I måske, at denne vil kunne sparke røv.??

http://www.cinemagic.dk/pioneer_s_w_160_s_k_aktiv_subwoofer_ schwarz-p-897.html?osCsid=b25818eafbc46c678b998acf0bd89c83

 

 

Den skal have samme design, som den jeg har nu.

Og den der er her er større end den jeg har nu.

http://www.cinemagic.dk/pioneer_s_w_160_s_k_aktiv_subwoofer_ schwarz-p-897.html?osCsid=b25818eafbc46c678b998acf0bd89c83

Og den passer i designet..