Pozicioniranje Zvucnika

[Mikorist]

Idealno podesavanje moze da bude iako su zvucnici stavljeni na zvucnicke stalke, montirani na zid, ili na policama.

Ovako bi trebalo odprilike da izgleda:

Visokotonci bi trebali biti na jednakim visinama oko visine uva (kada se sedi) kako bi se sto bolje culi. Ako je moguce, namestiti, tako da udaljenost izmedju Audiofila i centra zvucnika bude 1.5 puta od udaljenosti izmedju zvucnika (kao na slici).

Ovo je najbolje izvesti na stalcima (ako nisu podno-stojeci zvucnici), stalci trebaju da budu oko 29 cm visoki (ovo moze da varira u zavisnosti od visine visokotonaca), a da se nalaze na najmanje od 12 cm od zida pozadi (iza zvucnika) i najmanje 30 cm od strane zidova.

Eksperimentisanje je naravno kljuc pronalazenja najboljeg mesta za slusanje.

ako zvucnik ima karakteristike 85db / 1W /1m

Zvucnik ce proizvesti zvuk od 85db, 1m dalje, kada se daje izlazna snaga

od 1 W-ata.

Zvucnik sa 100db na 1 metar meri 106db na 50cm ili 84,44db na 6 metara.

Ovde je kalkulator koji ce priblizno izracunati predvidjeni maksimalni nivo zvucnog pritiska na optimalnoj poziciji.

Cetiri ulazna podatka su potrebna plus

jedan opcioni:

http://myhometheater.homestead.com/splcalculator.html

posto su mere u feet-ima ovde imate koverziju metara u feet-e:

http://www.boatsafe.com/tools/meter.htm

Razmisljajte i o gubitku sluha:

http://www.hearnet.com/at_risk/risk_aboutloss.shtml

Svako "zlatno uvo" moze da postane i gluvo!

Nije sve ni u pozicioniranju...

[Mikorist]

A little more into boundary conditions

The Front wall, ipsilateral side wall, and floor will all cause big issues with your frequency response that will be audible d/t the ear's increased integration time as frequency goes lower. In other words, we don't hear with the greatest time resolution at low frequencies so we'll hear the reflections as part of the source. This is why I like wavelets--but that's been touched on earlier in the DTM Blog. The contralateral wall, ceiling, and possibly even the rear wall will also come into play and more so in a small room I imagine. As the distance of the reflecting surface gets further away from the source, the less pronounced the dip will be thanks to the Inverse Square Law--every time you double the distance, you loose 6dB.

The equation for the front wall interference:

Cancellation notch frequency = [(344m/s) divided by (4 times the distance from the speaker to the wall behind it in meters)] (344m/s)/4Dm=fHz

picture for reference:

A quick Table for reference:

This equation for other significant boundaries:

notch frequency = [(344m/s) / 2(the distance of speaker to the listening position via the reflecting surface - the direct path distance from the speaker to the listening position)] (344m/s)/2(Drm-Ddm)

This picture may help with visualization:

floor bounce

A couple more quick reference tables for this SBIR modifier:

..................................

For an online calculator (metric) go here:

http://mehlau.net/audio/floorbounce/

For sidewall reflections:

http://mehlau.net/au...ction_sidewall/

So for a practical example:

We have our speaker on a 3 foot stand. Its Baffle is 4 feet from the front wall and we are sitting we are sitting 9 feet from it at a listening height of 3 feet. That gives us enough information to find 2 of our first notches. The front wall will cause an approximate 70 Hz notch while the floor bounce will be a little over 300Hz. Keep in mind that the ipsilateral wall will still have its say as will the modes and to a lesser degree the other boundaries. For the ipsilateral problem it will be necessary to go to mehlau.net for a decent calculation.

___________________________________________________________________________

The previous section was just the the start of

Comb Filtering

The comb filter starts at that first notch frequency related to the SBIR. If you double that frequency, the interference pattern from the reflected wave is actually additive due to its phase relationship with the original wave. It is now back in phase and thus you essentially have 2 sources reinforcing each other. That gives us 6 dB of gain. This kicks off a pattern of alternation cancellation and reinforcement for multiples of the original notch resembles the teeth of those cheap black plastic combs you all have with the teeth getting progressively closer together as frequency get higher. It will also become less pronounced with increased frequency d/t narrowing directivity in the MR/Treble.

Here's the expanded tables from the first section on the effects:

Floor Bounce

http://dtmblabber.bl...conditions.html

[zerowaf]

Imam prijatelja koji upravo završava nekakve obuke za tehničara zvuka ili kako bi se to već zvalo. Inaće svira gitaru u raznim bendovima gotovo od djetinjstva. Nije audiofil, ali je zato na ti sa razglasnom tehnikom i upoznat je sa uvjetima u studijima za snimanje. On tvrdi da je idealana visina visokotonca nešto malo iznad visine uha, te da na taj način dobijamo najbolji privid visine izvođača dok istovremeno ne gubimo na percepciji visokih tonova.Isprobao sam to kod sebe nakon što je njegov brat podesio visinu svojih zvučnika (brat je audiofil) na taj način i mogu potvrditi da je trik upalio i kod mene.Slobodno eksperimentirajte!

[dvv]

_{Miko, uz svo poštovanje tekstova koje si postovao, negde (više se ne sećam gde) sam pročitao da prilikom igranja sa pozicioniranjem kutija u sobi nije loše probati sve kako treba što se međusobnih odnosa daljine između dve kutije i obe kutije u odnosu na slušaoca tiče i sa pozicioniranjem kutija tako da naše uvo prilikom slušanja bude u ravni ne sa visokotoncem već sa centrom donjeg basa, ili samo basa ako je jedan. Racionale je bilo da to mnogo više liči na tipično slušanje u nekom klubu, gde su muzičari uvek malo izdignuti u odnosu na ravan ušiju slušalaca.}

_{Probao sam to nekoliko puta na nekoliko mesta i ponekada se stvarno može dobiti veoma zanimljiva tonska slika, a ponekada je bolje vratiti kutije u klasičnu poziciju. Poenta je, stvarno vredi probati pre donošenja konačne odluke.}