Positive-Feedback-v2.qxd 6/30/99 11:18 AM Page 1 Version 2 ... · Version 2 ™...

Positive FeedbackThe Advantages of FBX Feedback Exterminators®

• Automatic feedback control • More wireless mic mobility • Louder & clearer sound systems

Feedback and

the FBX:

the whole

story

Real-life

examples

of the FBX

in use

Page 9

The

entire FBX

product line

Page 17

INSIDE:SSttoorryy ooff FFeeeeddbbaacckk 1

EEqquuaalliizzaattiioonn 2

TThhee FFBBXX SSoolluuttiioonn 3

GGlloossssaarryy ooff TTeecchh TTeerrmmss 5

AApppplliiccaattiioonnss 9

TTrruuee MMoobbiilliittyyTTMM WWiirreelleessss 15

AAddaappttiivvee AAuuddiioo PPrroodduuccttss 17

WWhhoo UUsseess FFBBXX 19

"No one's ever taking the

POWER-Q off me. It's welded

into the (Spice) rack!"

– Mike Dolling

®

Version 2

™

Positive-Feedback-v2.qxd 6/30/99 11:18 AM Page 1

What is acoustic feedback?

Feedback is the loud ringingsound that occurs when thesound leaving a speaker ispicked up by a microphone andreamplified again and again.(See Fig. 1.) The cycle repeatsuntil the feedback reaches thesystem’s maximum loudness oruntil someone turns down thevolume. Virtually every soundsystem that has a microphoneand a speaker in the same roomis susceptible to feedback.

Which frequencies feedback? All acoustic systemshave distinct resonant frequen-cies. Regardless of where youthump a guitar’s top, it alwaysresponds with the same tone.This is the natural resonant fre-quency of the guitar. It is thefrequency where all of theinstrument’s componentsvibrate naturally as a unit. Insound systems, these resonantpoints are the frequencieswhere feedback occurs.

Each of the system’s com-ponents, including and especial-ly the room itself, has its ownset of resonant frequencies.

By Doran Oster, President

Ever since Lee DeForestinvented the first vacuumtube, engineers have walkedthe tightrope between feed-back and system gain. Thepurpose of this guide is to giveyou the tools to get all thegain you need without theagony of feedback. We’ll startwith a common-sense discus-sion of the techniques soundengineers now use to controlfeedback to get the most gainand clarity out of their soundsystems.

Our imaginary work bench

Imagine a mic and speak-ers set up in a tiny showerroom. Clap your hands. Thesound reverberates back andforth between the tile wallsand floor. Just a touch of thevolume fader fills the roomwith screeching feedback.

Now move our sound sys-tem out to an opengrassy field. Clap yourhands. There is noecho. The speakers arewell away from themicrophone and thereare no reflections, sonow we can really crankup the system without abit of feedback.

Most sound systemshave characteristics thatfall between these twoexamples, but examin-ing the extreme cases makesit easier to understand themore common in-between situ-ations.

Each component adds togeth-er to produce the total sys-tem’s resonant frequencies. Itis almost impossible to predictwhich frequencies will feedback without first “thumping”the system, but you only haveto turn up the amp for them torudely reveal themselves.

The frequency that feedsback first is the one thatrequires the least amount ofenergy to excite the resonance.If you remove the first feedbackfrequency, the next feedbackfrequency will be the one thatrequires the second leastamount of energy, and so on.

Controlling feedback In order for feedback to

occur, the amplifier has to beturned up enough so thatsound from the speaker re-enters the microphone louderthan the original sound. In ourimaginary experiment, feed-back easily occurred in theshower room because the

sound leaving thespeakers did notdissipate verymuch before re-entering themicrophone. Butwhen we movethe speakersaway in the openfield, the soundenergy dissipatesas it radiatesaway from thespeakers. If there

are no surfaces to reflect thesound back to the mic, thesound quickly loses energy,dropping to one quarter the

1

The Story of Feedback

Fig. 1: Feedback Loop

Positive-Feedback-v2.qxd 6/30/99 11:18 AM

energy every time the distancefrom the speakers is doubled.By the time the sound finallyreaches the microphone, thesound energy is weaker thanthe original sound, so there isno feedback. From this exam-ple we deduce the PrimeDirective of Feedback Control:

Keep the sound emanat-ing from the speakers awayfrom the microphones asmuch as possible.

Here are the most com-mon tricks of the trade forcontrolling feedback:• Stand close to the micro-

phone. Speak loudly andclearly so that you do not haveto amplify the sound too much.• Each open microphone

has a chance to feed back.Mute or turn down the gain ofany microphone that is not inuse. Noise gates can be help-ful for this.• Mount the microphones in

fixed positions. Moving themicrophone around on thestage increases the chancesthat the microphone and thespeaker will form new resonantpaths.• Use cardioid or hyper-car-

dioid microphones, and pointthe mics away from thespeakers. They pick up muchless sound from the back sideof the mic, which protectsagainst monitor feedback. Becareful not to put your hand onor too close to the micro-phone’s screen, since this cancover the ports that enable theheart-shaped (hence cardioid)rejection pattern.• Place the speakers in front

of the microphones so thereis not a direct path back to themicrophone.• Aim the speakers so the

sound does not reflectdirectly off a wall back intothe mic. You can estimate thespeaker’s dispersion pattern

(the area that is directly“sprayed” with sound) for themids and high frequencies byimagining rays of light radiatingout of the speaker’s horns. Ifyou can see the center part ofthe horn, you are probably inthe dispersion pattern. Lowerfrequency sounds tend to radi-ate out in all directions from allsides of the speakers.• Make the surfaces of the

room as sound absorbent aspossible to reduce soundreflections. Use acousticalabsorbing tiles in the ceiling, putdown carpeting, and hangcurtains.

In the real world of mostperformance spaces, you can-not always follow these anti-feedback techniques. Leadsingers insist on pointing themonitors directly at the mic.Worship leaders insist on themobility of a wireless micro-phone, and night club ownerswill not likely carpet the dancefloor and hang velvet curtains.Even after you’ve tried all thesetricks, you may still not haveenough gain and clarity to satis-fy the audience. Do the bestyou can, and then go on to thenext level of feedback control:equalization.

EqualizationEqualizers (EQs) are sets

of filters, or volume controls, fordifferent parts of the audiospectrum.

Since the earliest days,sound engineers have usedequalizers for two distinctly dif-ferent purposes: 1) To improvethe tone quality and balance ofthe sound, and 2) To controlfeedback for extra gain andmicrophone mobility. Sometypes of EQs are best at shap-ing the tone and other types arebetter at controlling feedback.

It may seem paradoxical toadd filters to a sound system inorder to increase the gain. But

if you can use extremely narrowfilters to turn down the frequen-cies that are feeding back, youwill be able to increase the gainof all the other frequencies for atotal net gain. There areessentially three categories ofequalizers: graphic, parametricand adaptive parametric.

Graphic EQGraphic EQs are basically

a set of volume controls forindividual sections of the audiospectrum. The earliest musicequalizers were the bass andtreble tone knobs. As technolo-gy advanced, these filters werenarrowed to give more precisecontrol. Today, the industrystandard is called a 1/3-octavegraphic equalizer, which has 31individual volume controlsspaced 3 per octave.

There is a common miscon-ception in the industry about1/3-octave EQs that is impor-tant to this discussion. Manyindustry veterans incorrectlypresume that 1/3-octave EQsuse 1/3-octave wide filters. Ifthis were the case, the EQ fil-ters would not be wide enoughto create smooth curves.Instead, they would produce anotched frequency responsethat would make the EQ use-less for shaping the sound anduseless for controlling feedbackfrequencies between the slid-ers. Actually, most manufactur-ers use 3/4 to 1-octave wideoverlapping filters placed on1/3-octave center points. Thesewider filters provide the neces-sary smooth frequencyresponse. (See Fig. 2.) It’simportant to understand thatthe term “1/3-octave” refersto the spacing of the sliders,not the filter width.

Graphic EQs are excellentfor shaping the sound, and theyare fairly simple to use.However, using one-octavewide EQ filters to control feed-

2

EQUALIZATION


back invariably causes anunnecessary decrease in thegain and fidelity of the program.It’s easy to see that if feedbackoccurs somewhere between thesliders, you will have to pull oneof those EQ sliders down prettyfar to eliminate feedback. Thatpulls out plenty of your program,too. On the other hand, you’llget considerably more net gainand much better sound quality ifyou use wide graphic EQ filtersfor tone control and insist onnarrow filters for feedback con-

trol. (See Fig. 3.) That’s whereparametric EQs come in.

Parametric EQIn the quest for perfect

sound, engineers developedvery narrow tuned filters forcontrolling feedback points inauditoriums. In the early daysof sound reinforcement, thesefilters were custom made to aspecific frequency and width fora specific application. Nowthere are a number of commer-cially available parametric filtersets that allow engineers to dial

in the width, center frequencyand depth of the filter.

The problem with para-metrics is that they’re expen-sive, they require a good dealof expertise and auxiliaryequipment to tune properly,they require constant retuningwhenever the room acousticschange, and they are far tooslow and cumbersome forcatching feedback that occursduring the program.

Adaptive Parametric:The FBX Solution

The Sabine FBXFeedback Exterminator® is thenext step in the evolution offeedback control. The FBX isessentially a self-tuning para-metric EQ. It constantly moni-tors the program, searching fortones that have the overtonesignature of feedback. Oncefeedback occurs, the FBXautomatically places a verynarrow, constant-width filterdirectly on the feedback fre-quency and lowers it just deepenough to eliminate the ring-ing sound.

The FBX out performs other EQs five ways:

1. The FBX finds and elimi-nates feedback automaticallybefore and during the program.

2. The FBX’s narrow filterseliminate feedback without los-ing the fidelity of the sound.

3. The FBX is fastest. It typi-cally finds and eliminates feed-back in less than one second.

4. The FBX gives the mostgain. Use wide-filter graphicEQs for controlling the shapeof the sound and narrow FBXfilters for controlling feedback,and you’ll typically achieve a 6to 9 dB increase in gain com-pared with using the EQ alone.

5. Increase wireless mic mobility.

Typical Graphic EQ:-10 dB cut at 500, 630, 1K, 1.25K, 1.6K & 2K Hz

If the graphic EQ really had 1/3-octavefilter widths, the frequency responsecurve would vary 6 dB between sliders.This would ruin the sound.

Graphic EQ’s usually use oneoctave wide overlapping filtersthat provide much smoother fre-quency response curves. Noticethat the overlapping filters addtogether to cut -16 dB when thesliders are only pulled -10 dB.

3

Fig. 2: Graphic EQ

THE FBX SOLUTION


What about that 6 to 9 dBincrease in gain? Gainincrease from equalization real-ly depends on the characteris-tics of the sound system andthe room. Returning to ourimaginary system in the showerroom, the sound bounces offthe hard tile surfaces andreflects back into the micro-phone with only a slight touchof the volume slider. If you fil-ter the first feedback point, youcan only increase the volumefader a touch more before thesecond feedback occurs at anew frequency. Even if you fil-ter six different resonancepoints, you may only achieve 1or 2 decibels of net gainbecause there are so manylow-energy resonant paths.

When we set our system ina large open field and thespeakers are far away from themicrophone, we really have tocrank it up before we hear thefirst feedback. We would needan enormous system to drivesix feedback points. In thissystem, damping six feedbackpoints could easily deliver wellover 15 dB net gain!

How much gain do youachieve with the six FBX fil-ters? Six resonance pointsworth - whatever that happensto be in your unique system.You can maximize your gain byfollowing our anti-feedbackdirectives and by learning moreabout how the FBX filters workbest for your situation. Microphone Mobility

Mobile karaoke and wire-less microphones present aspecial feedback challenge. Itdoes little good to set a numberof filters for a mounted micro-phone if you plan to carry themic around the stage to differ-ent locations. Each position onthe stage has its own uniqueset of resonant frequencies, sothe filters that control feedback

in one location will probably notprovide much help in otherlocations.

You are faced with a bal-ancing act. If you insert toomany filters in the system, youwill hear a degradation of thesound quality. If you set toofew filters, you will not haveenough mobility or gain.

In this case, it is usually bestto walk around the stage areauntil you find an area wherefeedback is a particular problem.Then place one or two feedbackcontrol filters to take care of thatlocation and repeat the processin the next few areas. FBX fil-ters add less gain to mobile sys-tems than to fixed microphonesystems, but they add a signifi-cant increase in the usable areawhile preserving the naturalclear sounds.Feedback Control During the Program

One of the most powerfulfeatures of the FBX is that itcan eliminate feedback duringthe program. FBX filters comein two types: fixed and dynam-ic. Both filters are placed thesame way: Feedback is detect-ed, and the filter is placed justdeep enough to eliminate it.The difference comes after thefilter is placed. Fixed filtersremain on the initially detectedfeedback tone - they do not

move. These filters provide theinitial maximum gain beforefeedback and are set automati-cally during setup. Dynamic fil-ters can release and move tonew feedback frequencies andare for adaptive feedback con-trol during the performance.You can change the number offixed vs. dynamic filters using

front panel controls.Hearing is Believing

To hear the difference foryourself, insert an FBX in yoursound system and bypass it.Mount the mics on stands to fixtheir positions. Remove asmuch feedback as possibleusing your normal method withjust the graphic EQ. Next, lowerthe volume, bypass the graphicEQ, and activate the FBX. Nowslowly raise the gain of the sys-tem until at least six FBX filtershave kicked in.

Next, turn down the micsand play your favorite CDthrough the system. Alternatelylisten to the system with just theFBX and then just the graphicEQ. You will hear the FBX pro-vides much clearer, brighter andlouder sound.

If you do not have immedi-ate access to an FBX, run thisexperiment with a graphic EQalone. You will be amazed tohear what it does to your sound.

SEE THE GLOSSARY ON THE NEXT PAGE (p. 5)FOR DETAILED EXPLANATIONS OF SOME OF THETERMS USED HERE.

Fig. 3: FBX vs. 1/3-Octave Graphic EQ

4

THE FBX SOLUTION

A PA System was setup using a micro-phone, mixer, FBX,power amp and twospeakers. The sys-tem’s gain was raiseduntil the FBXremoved nine feed-back points. Next theFBX was replacedwith a graphic EQ.The EQ was adjustedwhile the system gainwas raised to thesame level achievedwith the FBX. Thefrequency responsecurves of each devicewere then plotted.


5

TECH TERMS

GLOSSARY:Definitions of“tech” termsWhat is Gain?

Gain is a measure of thechange in power (or loudness)in a sound system. For exam-ple, turning up the amp causesan increase in gain, while mov-ing away from the speakerscauses a decrease in gain. Byconvention, gain is expressedin decibels.

ClipGuardTMAdaptiveClip Level Control

Sabine’s ClipGuardTM

makes FBX feedback controlfaster and easier to use, andit adds about 10 dB to theeffective dynamic range. UntilClipGuard, engineers manuallyset the input and output levelcontrols to a compromise set-ting that causes unnecessarynoise during quiet programsand risks clipping overloadduring high level programs.Now ClipGuard constantlyreadjusts the FBX’s electronicsto match the continually chang-ing program levels.

Another feature ofClipGuard is TURBO modethat cuts the time of the pre-program setup to just a fewseconds. ClipGuard is currentlya standard feature in Sabine’sFBX-1020P & 2020P FeedbackExterminators, POWER-QADF-4000, GRAPHI-Q,DQX-206 parametric EQ/delayand the REAL-Q2 Real-TimeAdaptive Equalizer.

Noise Gate/Comb Filters

As we mentioned earlier,every microphone creates apotential source of feedback,

so it is advantageousto turn off microphonesthat are not currentlybeing used. Noisegates do this automati-cally by continuouslymonitoring the pro-gram’s loudness. If theloudness falls below athreshold set by theuser, the noise gateautomatically turns offthe microphone. Oncethe loudness exceedsthe threshold, themicrophone channel automati-cally turns back on.

Noise gates are useful fora number of important soundapplications besides feedbackcontrol. For example, if a per-son or instrument is picked upby two microphones placed indifferent locations, the com-bined mic signals will interferewith each other, causing a typeof distortion called comb filters.Comb filters add gain at certainfrequencies and thus increasethe chance of feedback. At thesame time, they cut the gainat other frequencies, causingthe program to sound thin andover-equalized. Gating the

unused microphones eliminatesthis source of comb filtering.

Noise gates are oftenemployed in CD players toeliminate noise between songs.They are similarly used insound systems to mute the hissof noisy electronic componentsduring quiet periods.

Most Sabine FBXFeedback Exterminatorsfeature user-progammablenoise gates.

What are Decibels?We have the ability to hear

an amazing range of loudness.People placed in an absolutelyquiet anechoic chamber eventu-

1K EQ slider pulled down 12 dB

Fig. 4: Loudness in Decibels

Fig. 5: Typical Frequency Response


6

TECH TERMS

ally perceive the sound of airmolecules hitting theireardrums. On the other hand,people working near jetengines hear sounds a billiontimes more powerful.Engineers have developed aconvention that economizesthe calculations of such anenormous range of values.This convention describesthese changes in terms ofdecibels (abbreviated dB)named in honor of AlexanderGraham Bell.

Many non-technical peoplefind the different uses of theterm decibels confusingbecause it seems to have somany different meanings. Forexample, decibels are com-monly used to describe theloudness of a sound, thechange in loudness (or gain)from one time to another, forchanges in signal voltage, anda number of other technicalmeasurements involving thepower ratio of large numbers.While we gladly leave thesecalculations to the engineers, itis helpful to realize that achange of 1 dB is equivalent toa 27 percent change in power.

With this in mind, we realizethat turning up the system gainby 3 dB increases the powerapproximately 100% (27% x 3).In other words, turning up theamp from 400 Watts to 800Watts adds about 3 dB to thesystem gain.

Wow! Does doubling thepower from 400 Watts to 800Watts make it sound twice asloud? No! A three decibelchange sounds only slightlylouder. In general, you have toincrease the power about 10times (or 10dB) to make thesound seem twice as loud.

When engineers describethe loudness of a sound interms of decibels, they arecomparing the sound pressurelevel of a particular sound com-pared to an international stan-dard. Fig. 4 gives several com-mon reference points.

Frequency Response Curves

A frequency responsecurve is a graph that shows thegain of a component or a groupof components at different fre-quencies. Fig. 5 shows the fre-quency response of a typical

equalizer with the 1,000 Hzslider pulled down 12 dB. Thefrequency response curveshows that the biggest cut inpower, called the center fre-quency is at 1,000 Hz, that thefilter removes half of thepower (-3dB) between 645 Hzand 1550 Hz, the Q of the fil-ter is 1550-645 Hz/1000 Hz(.905), and the maximumdepth is -12 dB.

Fig. 6 shows the frequencyresponse of two adjacent slid-ers pulled down 12 dB. Noticethat the center frequency of thetwo sliders is at 885 Hz. Thecombined filter width is 1.49octave and the two filters addtogether to give a maximumdepth of -19.3 dB.

Constant-Q Filters It is common to describe a

filter’s quality factor, or “Q,” asthe center frequency of the filterdivided by the filter width (inHertz) measured at the -3dBpoint. Filters that have thesame Q, or width, at the -3dBpoint regardless of the filter’scut or boost are called constantQ filters. Filters that get wideras the filter gets deeper arecalled proportional Q filters.

There seems to be a newdevelopment in the audioindustry. The definition of con-stant Q is blurring. Manyequalizer manufacturers claimtheir equalizers have constantQ filters, when in fact they getsubstantially wider as they getdeeper. The only way to knowfor sure if the filters are trulyconstant Q is to inspect theirfrequency response curves.(See Figs. 7 & 8.)

Net Gain Before Feedback

Many people measure theirincrease in gain by the amountthey push up the mixer’s cali-brated slider. But if adding gain

Two overlapping EQ sliders pulled down 12 dB

Fig. 6: Typical Frequency Response


7

TECH TERMS

causes feedback, you willhave to cut the gain of thefeedback frequency at the EQin order to add gain at themixer. A more accurate con-cept could be called NET gain.It is the amount of gain youachieve pushing up the mixerslider, minus the gain you loselowering the EQ sliders. NETgain is the gain you realize infront of the speakers as mea-sured by a sound pressurelevel meter. That is the gainthat matters. (See Fig. 9.)

The Frequency Spectrum

People with excellent hear-ing can hear frequenciesbetween 20 and 20,000 vibra-tions per second or Hertz. Fig.10 shows an imaginary 120key keyboard that would bebig enough to play all thenotes that we can hear. Thelowest key would play a 20 Hz“E” and the highest key wouldplay a 19,912 Hz “D#.” Noticethat doubling the frequencyraises the pitch one octave.We hear the same one-octavemusical interval between 40and 80 Hz as we do between10,000 and 20,000 Hertz.

A graphic equalizer issuperimposed that showswhich sliders affect the notesof several instruments. Forexample, the chart shows thatthe 250 Hz slider affects mostof the bottom 1/3 of a guitar’srange.

The typical FBX filterbelow the EQ shows the rela-tively smaller size and effecton sound of FBX filters andillustrates why they cause lesstonal change and gain loss.

The nine FBX filters arenot preset on any particularfrequencies like EQ filters.They are placed preciselywhere feedback occurs.

Fig. 7: Typical Constant Q Filter

Fig. 8: Typical Proportional Q Filter

Fig. 9: Net Gain = Mixer minus EQ


8

TECH TERMS

Fig.

10:

The

Fre

quen

cy S

pect

rum

©19

97 S

abin

e, In

c.

Horiz

onta

l bar

s sh

owpr

actic

al ra

nges

of

mus

ical

inst

rum

ents

.Li

ght g

ray

shad

ed a

rea

show

s to

nes

affe

cted

by o

ne g

raph

ic E

Qfil

ter

(250

Hz)

. No

te la

rge

gaps

in re

spon

se o

fm

any

inst

rum

ents

whe

nju

st o

ne E

Q fa

der i

spu

lled!

Com

pare

this

toth

e m

uch

narr

ower

are

aaf

fect

ed b

y on

e FB

Xfil

-te

r (da

rk g

ray

bar).


9

APPLICATIONS

Every Friday evening at 6:00all of Britain celebrates the startof the weekend with the hit tele-vision show "TFI Friday."Hosted by star Chris Evans, TFIFriday features an informal "bigbar" setting as a backdrop forentertaining conversationbetween host and guests, plusthe occasional musical act.Adding to the normal mayhemand stress of a weekly televisionproduction is the fact that theshow is broadcast live to mil-lions of devoted fans. Then con-sider that Chris and his guestslike to wander around the setduring the course of their con-versations – with their lavaliermicrophones amplified to quiteloud levels for monitoring pur-poses. Finally, throw in not justone, but three sound stages forlive music, and you might think asound engineer in charge ofsuch a setup would long wistfullyfor a carefree career as a pro-fessional mine sweeper or someother less stressful occupation.

Not so Chris Trimby, monitorengineer extraordinaire, incharge of 16 monitor mixes forTFI Friday. Chris, whoseLondon rental company ENTECsupplies all the sound require-ments for the show, has made

his demanding job far lessstressful by harnessing a total ofeight Sabine POWER-Qs (plus 2in rotational duty), all controlledfrom a central computer station.

"The POWER-Q containsevery possible bit of informationyou could ever need to detectproblems and then put them rightin a fraction of the time it wouldhave taken using traditionalmethods," states Chris. "Set-uptime for the POWER-Qs isremarkably fast. Via the PC, allthe machines copy to each other,so once one is programmed,they can all be preset. By thetime the show airs on Friday, Ican virtually put my feet up! Iget an extra 9 dB of gain beforefeedback! It's a real joy to mix."

Chris uses all the features ofthe POWER-Q, but especiallyfinds the EQ and powerful FBXnotch filters useful in preventingany surprises during the show'slive broadcast. He also uses theunit's delay, compression, limit-ing, and Real Time Analyzer andcurve display. Chris finds thepotential uses of the POWER-Qalmost limitless. "I am discover-ing new ways to manipulate thesystem all the time," claimsChris. He describes thePOWER-Q's flexibility as anabsolute essential in live televi-sion, where the limits are alwaystested and new problems are aconstant challenge. "Sabine’sPOWER-Q is the perfect tool forthe job."

Thanks to Kiera Leeming ofFuzion, Sabine's UK distributor,for her assistance in compilingthis information.

Sixteenchannelsof moni-tors:

ChrisTrimby &TFI Friday

POWER-Q

Chris Trimby


10

APPLICATIONS

Using theFBX inchurches:

DaytonaBeachAssemblyHall of theJehovah’sWitnesses

POWER-QFBX-1020Plus

Sabine's adaptive audio prod-ucts provide a gentle but power-ful application of technology tosolving acoustical challengespresented by both historic hous-es of worship, and brand new,modern facilities. That's whyyou'll find the name "Sabine" inuse all over the world, in placesof worship of all shapes, sizes,and denominations – from thehuge scale of the Vatican inRome (GRAPHI-Qs and FBXs)and the Grand Mosque in Mecca(a rack full of FBX-1020Pluses),to small churches and modestministries.

Somewhere in between thelargest and smallest house ofworship is the 2,200-seatAssembly Hall of the Jehovah'sWitnesses in Daytona, Florida.Here Sabine's POWER-Q pro-vides feedback-free sound andworry-free operation, perfectlysuited for quiet contemplation orfestive celebration.

Contractor Larry Kommers ofSight & Sound in Laurens, SCcalls the POWER-Q a “powerfuland essential” piece in theAssembly Hall's sound system."We chose the POWER-Qbecause we knew we could usethe equalizer, the FBX FeedbackExterminator®, the compressor/limiter and the real-time analyzer– without a bunch of boxes allhaving to be converted back andforth from digital to analog. Itmakes for a much cleaner instal-lation," asserts Kommers.The Assembly Hall installation

makes good use of the POWER-Q many functions. "We are usingparametric EQ, graphic EQ, theFBX and the compressor," statesKommers. "And of course weused the auto-EQ function to setit up. We also use the displayscreen on the POWER-Q tomonitor what's going on in theaudio signal," he continues.

The POWER-Q's ease ofoperation also helps assureagainst system failure. Kommersinstalled two completely identical,redundant systems into the mainauditorium. "Now these systemshave to be dead equal to eachother," states Kommers. pointingto the POWER-Q precision asanother reason to buy one. "Withthe POWER-Q, we can very eas-ily get the exact same equaliza-tion, exact same compression,and the exact same configurationfor the sound on each of them.During the program we can hitthe switch to go from standbyand the audience will never hearthe switch – never detect that itis now going through differentequipment."

The POWER-Q is not the onlySabine equipment installed with-in the Assembly Hall. Kommersused a Sabine FBX-1020Feedback Exterminator® for thestage monitors – making surethat "the people on the stagecould hear what the audiencewas hearing – without causingany feedback."

Since the Assembly Hallopened its doors in January,1999, the sound system hasreceived nothing but praise."We are delighted with thesound," says William Heien,manager of the Daytona BeachAssembly Hall of Jehovah'sWitnesses. Kommers has hadrequests from other similarfacilities – one in New YorkState, one in Pittsburgh andanother one in Florida – to lookover their systems and giveadvice. Not surprisingly, “we aregoing to recommend usingSabine," asserts Kommers.

William HeienAssembly Hall Manager


11

APPLICATIONS

GRAPHI-Qon Board

GRQSavesFerry fromStructuralOverhaul

loving DJs. With the exceptionalversatility of the GRAPHI-Q, heliterally saved the client thou-sands of dollars in unnecessaryconstruction costs with an amaz-ingly simple solution.

This same GRAPHI-Q versa-tility allows the the ship's club tosuccessfully host a variety ofapplications, from techno ravesto business meetings requiringonly vocal microphones at a lowvolume. The GRAPHI-Q's sepa-rate compressor and limiteradjustments allow MHH to, first,boost sound levels for low-vol-ume uses of the sound system,and, second, to protect speakersfrom overload when the DJscrank it up. The FBX section ofthe GRAPHI-Q protects againstfeedback when microphones areoperated by unsophisticatedusers, or when the system gainis set to high levels. The pro-grammable and recallable graph-ic and parametric EQ settings ofthe GRAPHI-Q enable selectionof different EQ curves for differ-ent applications. And, finally, thedigital delay of the GRAPHI-Qenables time alignment of themultiple speaker clusters neededfor even sound distributionthroughout the expanse of thelarge club.

So club goers enjoy greatsound, and weary passengersenjoy sound sleep, and Asconand MHH sleep well at night withthe knowledge of a job welldone, all thanks to the exception-al power of the GRAPHI-Q.

nant chamber, and the thud ofbass drums and other low fre-quencies were being transmittedto distant decks through the hullof the ship.

Musik Huset Hjorring (MHH),the installation contractor, pro-posed a solution that wouldrequire difficult and expensivemodifications to the stage con-struction. Fortunately, prior totheir undertaking such costlyaction, they called Ib Sigismundof Ascon, the Danish distributorof Sabine pro audio products.Ascon had already providedMHH with 2 Sabine GRAPHI-Qs(GRQ-3102 units) for the installa-tion. MHH was initially attractedto the GRAPHI-Q because of itspowerful combination of features(2-channel compressor, delay,graphic equalizer, parametricequalizer, and of course Sabine'sindustry-leading FeedbackExterminator®), superb specifica-tions, and reasonable cost. Butwhat clinched the purchase wasthe fact that the GRAPHI-Q istruly tamper proof. After toomany unpleasant past experi-ences where glass protectionpanels failed to keep the grem-lins away from the controls, MHHwanted a product with true tam-per lock out.

The GRAPHI-Q delivered allthis … and one more very impor-tant benefit: a simple solution tothe bass propagation problem.While monitoring the GRAPHI-Qsoftware over the course of anevening's entertainment,Sigismund noticed that certainlow frequencies resonated soextremely that they actuallycaused FBX filters to set – allclustered between 50-60 Hz.After a little experimentation,Sigismund determined that avery narrow and very deep para-metric filter around 55 Hz bothsolved the resonance problem,and left the sound system qualityintact even for fanatical bass

G R AP H I -QG R Q -3 102

Ib Sigismund

The quest for bigger and bet-ter almost put the Danish ferry-boat Christian IV in for structuraloverhaul – that is, until Sabine'sGRAPHI-Q was called in to solvethe problem.

The nightclub on the ChristianIV offers such a powerful soundsystem that the bass frequenciesenjoyed by its patrons were dis-turbing the sleep of passengersthree decks away. The club'smetal stage, and an array of sub-woofers placed underneath it,combined to act as a huge reso-


FBX &REAL-Q2in themeparks:

BuschGardens

A world class theme park isdesigned to provide an excitingescape from everyday life. Hardat work behind the scenes is ateam of clever engineers,designers, and technicians,working as invisibly as possibleto blur the boundaries betweenreality and fantasy.

The fantasy world of a themepark is far more compelling whenthe equipment that helps createit is both transparent in its opera-tion, and absolutely reliable. AtBusch Gardens in Tampa,Florida, that means that audiodesigner Brian Rudolph is speci-fying Sabine products in everytheater and live sound venuethroughout the park. Brian isusing a full palette of Sabineproducts, including POWER-Qs,REAL-Q2s, SDA-102 delays,FBX-1020Plus and FBX-2020Plus units.

"Sabine products have savedmy tail many times," Rudolphclaims. As an example, hedescribes the audio challengespresented by the park's Dragon'sTail Children's Theater in theLand of the Dragons, whereloudspeakers are located twofeet above the actors' heads."Every area of the stage was afeedback nightmare. We triedconventional EQ's with no luck,

but had instant results when weadded FBX. Sabine turned asound engineer's nightmare intoa sleeper."

At the Marrakech Theater(part of Busch Gardens'Morocco exhibit), Rudolph hasbeen using a REAL-Q2 to auto-matically adjust systemresponse – an area subject todrastic changes from both cli-mate fluctuations and audiencesize. Brian observes, "It's runflawlessly since we installed it,through all kinds of conditions,and all sizes of audiences, pro-ducing consistent quality audio.In this kind of situation, youcan't expect to install a stan-dard graphic EQ, set it andleave. Buy you CAN do thatwith the REAL-Q2."

From the FestHaus (SabinePOWER-Qs used for EQ, delay,and feedback control) to theBird Show (SDA-102s used forspeaker alignment), BuschGardens now sports one of theworld's densest concentrationof Sabine products. Not sur-prising, since Rudolph claims,"Sabine makes great stuff, andit's made my job easier and lotmore fun. It's so reliable it'seven survived a lightning hit. Ittook 5 minutes to reset it, andit's still running perfectly."

REAL-Q2POWER-QFBX-2020Plus

Brian Rudolph

APPLICATIONS

12


13

APPLICATIONS

Theacousticsetup:

J.D.Crowe& The NewSouth

Amplified acoustic musicalways presents an inherentlycontradictory situation. On theone hand, acoustic musiciansstrive for the intimacy and pres-ence of a living room perfor-mance. On the other hand, asaudience size grows beyond thedimensions of the living room,the musicians require amplifica-tion in order to be heard. Thechallenge for the sound engineeris to project sound to a largeraudience as free as possiblefrom coloration, and to preservethe natural balance of the instru-ments and voices in a musicalensemble.

One popular method ofachieving the right sound andbalance that is particularly popu-lar with bluegrass musicians isthe "one microphone" technique,where all the musicians cluster ina semi-circle around a singlemicrophone, and adjust theirpositioning and volume to essen-tially mix themselves.

J.D. Crowe and the NewSouth, one of the most success-ful and long-running bluegrassbands now working, employ aslight variation of the one micro-phone technique, using a singlemic for their three vocalists.According to group member PhilLeadbetter, the single micro-phone allows for a better vocalblend, but the band prefers tomic their instruments individually.

For the vocals, the group uses anomni-directional, largediaphragm, high output con-denser microphone. With thiscarefully honed setup, they areable to achieve an excellent livesound…with one major draw-back.

Leadbetter explains, "We playeverywhere from big festivals tosmall indoor clubs. Because thevocal mic gain has to be crankedup to get us the right sound,we're constantly battling feedback.The mic was almost impossibleto use in some situations…untilwe got a Sabine SM-820 to killfeedback."

Setup for the Sabine micro-phone-level FBX unit is simple:insert the unit between the micand the mixer. Output levels canbe set to match either mic or linelevel inputs on the mixer channel,and the sound quality of the 20-bit SM-820 is extremely transpar-ent.

"We used to spend a half houror more EQing the mic to soundright and not squeal. It wasalways a compromise. Now withthe Sabine we can set up in acouple of minutes, and the soundis great, loud and free from feed-back no matter how difficult theacoustics. We're real pleasedwith the Feedback Exterminator.You can't hear it working…whichmeans it's working perfectly."

F BX-S O LO S M-820

J.D.Crowe & The New South


APPLICATIONS

14

HouseSound onthe Road:

MikeDolling &The SpiceGirls

POWER-Q

Mike Dolling

One of the hottest acts in themusic business recently is theSpice Girls. With two mega-platinum albums behind them,the band has been touring theworld and selling out huge stadi-um venues to hordes of devotedfans. Of course, given the sizeof the venues, the success ofthe band, and the budget for thesound system, you can expectto see nothing but the bestequipment in the racks back atthe front-of-house mixing posi-tion.

Out of all this gear, MikeDolling, from England's topnotch hire company Wigwam,and FOH engineer for the SpiceGirls, has a favorite box. It's farfrom the most expensive piecein the rack, but, in fact, dollar fordollar offers one of the bestbuys in sound technology.

To say Mike Dolling loves hisSabine POWER-Q is putting itmildly. "No one's ever takingthe POWER-Q off me. It's weld-ed into the rack!" he declares.Mike is impressed by the multi-ple functions of the POWER-Q,the speed with which he can setup his system, and its trans-parency. "I can literally EQ thesystem with the POWER-Q insomething like a minute. It'samazingly quick. The FBX fil-ters are so transparent that we

don't lose anything from thesound but the feedback itself.As I get into using the delay,compression, gating, limiting,and expansion, this thing willreplace almost everything in therack – which will improve signalto noise ratio and cut theamount of stuff in the chain."

The Spice Girls recentlycompletely sold out a 40-city UStour, with POWER-Qs used forboth FOH and monitor mixes.

Mike Dolling continues to usePOWER-Qs in all his live soundgigs. Most recently he hastoured with the English phenom-enon "Boyzone," who also sporta multiple-vocalist lineup thatbenefits from the POWER-Q'stransparent operation.

Thanks to Mike Dolling, GrahamBlake, Dean Davoile of Fuzion,and Pro Sound News Europeanedition for information contribut-ing to this story.


15

SABINE WIRELESS

True MobilityTM

Wireless MicSystems:The Perfect Combination!

Targeted Input Processing:

• Patented FBX Feedback Exterminator®

The industry standard in automatic feedbackcontrol. The FBX includes our fast Turbo SetupMode.

• Auto De-EsserSabine’s new automatic de-essing algorithmsenses, tracks, and removes sibilance withoutaffecting the rest of your program.

• Compressor/LimiterOur famous digital compressor offers the gainmanagement you need to compensate for alltypes of performers and speakers, from thosewho are shy around microphones, to the bold-est worship leader.

With Targeted Input Processing, no mic getsmore processing than it needs, and every micgets precise, targeted control perfectly suited toprovide maximum performance. Until now youhad to settle for controlling your mics using com-promise settings on outboard gear. TargetedInput Processing gives you specific control overevery microphone – it’s the ultimate way to con-trol your sound.

Each True Mobility Wireless Receiver comeswith the all-digital Targeted Input Processing youneed for maximum performance, yet Sabine’ssystem costs no more than other far less power-ful UHF or VHF systems.

Sabine is proud to present the first wire-less microphone system with all the built-inprocessing you need on every microphone.Introducing Sabine True Mobility WirelessSystems.

Sabine Wireless Systems are superior toconventional systems because Sabine’sinclude the two most comprehensive fea-tures found in any wireless system: TrueMobility and Targeted Input Processing.

We call our system True Mobilitybecause it provides the freedom youshould expect from a wireless system. Witha conventional wireless system, your rangeof movement is limited by the potential forfeedback in acoustical “hot spots”. Someareas are so feedback prone you cannotgo near them. Other areas allow only mini-mal gain before feedback occurs.

Sabine’s True Mobility system includesour patented, industry-standard FBXFeedback Exterminator®. The FBX auto-matically kills feedback in setup and duringthe show, giving you a greatly increasedarea of feedback-free movement. Your micfinally will sound loud and clear, and you’llget the mobility you were hoping for whenyou chose a wireless system.

Sabine’s True Mobility doesn’t stop withautomatic feedback control. Conventionalwireless systems require the added cost ofoutboard processors to maximize perfor-mance. Sabine offers a different approach:on-board processing at no extra cost, alldedicated to one microphone. We call thisTargeted Input Processing.


SABINE WIRELESS

16

Sabine Wireless Systemscome in two models, with manyaccessories to complete yoursystem packages. The UHF sys-tem is a state of the art PLLsynthesized system with 30channels, True Diversity, dual-squelch circuitry, excellent noiserejection and superior dynamicrange. Choose a hand-held,lavalier, or headset microphone.

Our VHF system includes a16-channel PLL synthesized,True Diversity receiver with yourchoice of hand-held, lavalier, orheadset microphones. Both UHFand VHF systems offer optionalfront or rear mount antennas,extension antennas, and anten-na divider systems.

Visit your dealer today andget a Sabine True MobilityWireless System with TargetedInput Processing – your newchoice for the best in trouble-free wireless systems.

True Mobility systems give youwhat no other wireless offers:

• Increased mobility with no feedback• Increased gain and clarity• Increased intelligibility without sibilance• Virtually unlimited battery life• An adaptive system that compensates for all kinds

of performers and conditions – from concerts andtheaters to boardrooms and churches.

• All for no more money than you are currently spend-ing for high-quality wireless systems.

Built-In Dual NiMHBattery Charger!The only wireless systems thatpays for itself! No more wastingbatteries – always a fresh, long-lasting NiMH battery ready foryour microphone or transmitter.

UHF: 30 channels - or - VHF: 16 channels◆ True diversity ◆ Dual-squelch circuitry◆ PLL synthesized ◆ 10 Simultaneous channels (UHF)

SWM-3000 UHF SystemsSW-30R 30-Ch Receiver with Battery Charger / NiMH rechargeable batterySW-30H Condenser PLL Hand Held MicrophoneSW-30T PLL Belt Pack Transmitter

SWM-1600 VHF SystemSW-16R 16-Ch Receiver with Battery Charger / NiMH rechargeable batterySW-16H Condenser PLL Hand Held MicrophoneSW-16T PLL Belt Pack Transmitter

MicrophonesSWT-42L Unidirectional Condenser Lavalier MicrophoneSWT-25H Unidirectional Condenser Headset MicrophoneSWT-30G Guitar Interface (Plug and Cable)

BatteriesSWB-BAT Rechargeable 9-volt NiMH Battery

AntennasSWA-100 Rear to Front Antenna Converter KitSWA-4V VHF 4-Channel Antenna Divider SystemSWA-VEXT VHF Extension AntennaSWA-4U UHF4-Channel Antenna Divider SystemSWA-UEXT UHF Extension AntennaSWA-UB UHF Extension Antenna Booster

Mic & Transmitter AccessoriesSWC-200 Condenser Microphone Capsule ModuleSWC-CLIP SW-series Hand held Microphone HolderSWC-TRI Desktop microphone tripodSWC-101 Protective pouch for Belt Pack TransmitterSWC-4P 4-pin Connector

SW-30R True Mobility UHF Receiver


17

ADAPTIVE AUDIO

FBX-SOLO Feedback Exterminator, models SL-820 & SM-820Eight-filter unit automatically eliminates feed-back, providing more gain and increasedclarity. 20-bit digital in a small package. SL-820 has 1/4” in/out connectors and in/outlevel switches; for use with acoustic/electricguitars, mixer insert points. SM-820, withselectable phantom power, has XLR in/outconnectors; for use with balanced mics.Both have selectable noise gates.

FBX-1020 & 2020Plus Feedback ExterminatorsThe single channel FBX-1020Plus anddual channel FBX-2020Plus provide 20-bitdigital resolution, 12 feedback filters perchannel, ClipGuard™ adaptive clip levelcontrol with TURBO set-up mode, selec-table noise gate, lockable fixed filters andswitchable filter widths.

POWER-Q Multi-Function Processor Nine professional audio products in onelow-cost package. The choice of profession-als world-wide. 24-bit digital resolution,ClipGuard™ adaptive clip level control,automatic room equalizing, and 12 indepen-dent digital filters per channel, switchable toFBX-feedback control or parametrics; alsohas dual 31-band equalizer, full-featuredRTA, compressor/limiter, digital delay, noisegate, and 99 memories. Options includeremote control software, digital I/O, andblank front panel version.

REAL-Q2 Real-Time Adaptive Equalizer Automatically analyzes and equalizes yoursound space during program even if you’renot there, and automatically compensates forchanges in the frequency response curvecaused by the audience or changes in tem-perature or humidity. Provides full-featuredRTA and noise generator, digital graphic EQ,compressor/limiter, noise gate/expander,graphic display of the room’s responsecurve, remote control, and storage for up to99 different response curves.

FB

X-S

OLO

FB

X-1

02

0

& 2

02

0P

lus

PO

WE

R-Q

AD

F-4

00

0R

EA

L-Q

2G

RA

PH

I-Q

GR

Q-3

10

0

GRAPHI-Q EQ, FBX, Compressor, Delay All digital processing with an analog feel.Graphic EQ with high & low cut filters,patented FBX filters, compressor and delaycontrolled with “hands-on” front panel. GRQRemote software gives control over paramet-ric filters, limiter, and allows saving presets(68), linking units, channels, and functionsindependently. SIngle channel and dualchannel units available with and without frontpanel controls.


INPUT/OUTPUT - SL-820 ONLYI/O Connectors: 1/4” TRS; tip=input, ring=output, sleeve=groundInput Impedance: Unbalanced >1 meg OhmOutput Impedance: Unbalanced 10 Ohms nominal; Maximum load2K OhmsMaximum Input/Output Level at lowest gain: +20 dBVGain Range (with line out selected): 0 to +35 dB (high in), +30 to+65 dB (low in) Input to Output Gain @ unity setting: +/- 0.5 dBVBypass: Digital

INPUT/OUTPUT - SM-820 ONLYI/O Connectors: XLR-3 PIN 2 high BalancedInput Impedance: 1K Ohm nominalOutput Impedance: Unbal. 10 Ohms nominal; Max. load 2K Ohms

Maximum Input/Output Level at lowest gain: -10 dBVGain Range: -15 to +20dB (at high output)Input to Output Gain @ unity setting: +/- 0.5 dBVBypass: DigitalEIN: -105dBm @ 150 Ohms, 20Hz-17KHz or better Phantom Power: 48V switch selectable

PERFORMANCEFrequency Response: < +0.75dB, 20Hz to 17,000HzSignal to Noise Ratio: >87dB typical Total Harmonic Distortion: <0.02% @ 1KHz @ any gain settingDynamic Range: >92dB

POWER SUPPLY8-20VDC @ 400 mA

INPUT/OUTPUTInput/Output Maximum Signal Levels: Balanced +27dBV peak,unbalanced +21 dBV peakOutput Drive: Unit will perform as specified driving a load >600 OhmsInput Impedance: Balanced or unbalanced >10K Ohms, PIN 2 highOutput Impedance: Balanced or unbalanced 10 Ohms nominal,PIN 2 highBypass: True power off bypassHeadroom: +23dB peak @ 4dBV nominal input, balancedI/O Connectors: XLR-3 and 1/4” TRS

PERFORMANCESpectral Variation: < .25 dB, 20Hz to 20 KHzSNR: >100 dB, typical, “A” weighted THD: <0.02% @ 23 dBV sine wave at 1 KHzDynamic Range: >110 dB with ClipGuard™ automatic clip levelcontrol active

POWER INPUTFactory configured to either 115 VAC or 230 VAC. 50/60 Hz, 12Watt input.

FILTERSTwelve independent digital notch filters per channel which can becontrolled automatically or parametrically from 20 Hz to 20 KHz

DIGITAL DELAY1.3 to 83.2 msec. per channel in 20 microsecond stepsProgrammable in milliseconds, feet or meters.

NOISE GATE/EXPANDERAttack time: 1 to 99 msec. in 1 msec. stepsThreshold: -20 to -90 dBu in 0.5 dB steps

REAL-TIME ANALYZER31 band, 20 Hz — 20 KHz on ISO center frequenciesPeak-Hold, Fast/Slow displayA, B, C or Flat weighting

GRAPHIC EQUALIZER31 digital filters on ISO center frequencies, width from .5 to 1octave in .01 octave increments, +12 dB boost or - 15dB cut Independent display and control of channels A & B, or LINK

COMPRESSOR/LIMITERThreshold: +32 dBu to -30 dBu in 0.5 dB stepsRatio: 1:1 through infinityINPUT/OUTPUTInput impedance: Balanced > 10K Ohms, PIN 2 highOutput impedance: Balanced 10 Ohms nominal, PIN 2 highInput/Output maximum signal levels: Balanced +26 dBV peak Output load: 600 Ohms balancedBypass: true power-off bypassHeadroom: +22 dB peak @ 4 dBV nominal inputI/O connectors: XLR-3

PERFORMANCESpectral variation 10 Hz to 20 KHz, +/- 0.2 dB @ +22 dBVSNR: > 105 dB typical (with ClipGuard) THD: < 0.01% @ 22 dBV at 1 KHzDynamic range: > 110 dB (with ClipGuard)

POWER SUPPLY50/60 Hz available in 100 V, 120 V or 230 V; 25 W

ADAPTIVE AUDIO

18

INPUT/OUTPUTInput Impedance: Balanced >10K Ohms nominal, Pin 2 highOutput Impedance: Balanced 10 Ohms nominal, Pin 2 highInput/Output max. signal level: Balanced +29 dBV peakBypass: True power-off bypassOutput Drive: +28dBV peak into 600 Ohm loadHeadroom: +25dB peak at 4dBV nominal inputI/O Connectors: XLR-3

PERFORMANCEFrequency Response: +/-0.20dB, 20Hz to 20KHzSNR: >105dB typical (with ClipGuard)THD: <0.02% @ 22dBV at 1KHzDynamic Range: >110dB (with ClipGuard)

POWER SUPPLY: 100, 120, 230 VAC, 50/60Hz, 25 W

GRAPHIC EQUALIZERS31 digital filters on ISO center frequencies, width selectable from .5 to1 oct. in .01 oct. increments, + or - 15dB boost & cut, 20Hz to 20KHzSimultaneous display and control of REAL & Adaptive EQsSimultaneous display of RTA and REAL EQ

REAL-TIME ANALYZER31-band, 1/3 octave digital analyzer, 20Hz to 20KHzPeak-Hold, and Fast/Slow displayA, C or Flat weighting60, 30 or 15dB full scale displays with adjustable positionPink & white noise generators

COMPRESSOR/LIMITERThreshold: +26 dBV to 0 dBV in 0.5 dB stepsRatio: 1:1 through infinity

Partial Specifications shown. See product literature for complete information. Specifications subject to change without notice.

GRAPHIC EQUALIZER31 digital filters on ISO center frequencies, width from .5 to 1octave in .01 octave increments, +/- 6 or 12 dB boost or cut

FBX/PARAMETRIC FILTERSTwelve independent digital notch filters per channel which can becontrolled automatically or parametrically from 20 Hz to 20 KHzwith 1Hz resolution

COMPRESSOR/LIMITERFront Panel controls for Ratio, threshold, Gain; software controlsfor Attack, Release, Knee, Limit threshold

DIGITAL DELAY1.38 to 999.9 msec. per channel in 20 microsecond stepsProgrammable in milliseconds, feet or meters.

INPUT/OUTPUTInput impedance: Balanced > 10K Ohms, PIN 2 highOutput impedance: Balanced 10 Ohms nominal, PIN 2 highInput/Output max. signal levels: Balanced +26 dBV peak Headroom: +22 dB peak @ 4 dBV nominal inputI/O connectors: XLR-3

PERFORMANCEFreq. response: 20 Hz to 20 KHz, +0.0, -0.3 dB @ +22 dBVSNR: > 105 dB typical (with ClipGuard) THD: < 0.01% @ +22 dBV at 1 KHzDynamic range: > 110 dB (with ClipGuard)

POWER SUPPLY100, 120, 230 VAC, 50/60Hz, 18 W


19

WHO USES FBX

Iowa State Education SystemThe Rotunda (U. Va.)Northwestern CollegeUniversity of North CarolinaFull Sail Center for

Recording ArtsBangkok UniversityUniversity of Florida

MUSEUMS:Smithsonian InstitutionMuseum of FlightMingei International Folk Art

MuseumAmerican Museum of

Natural HistoryArizona Science Center

THEATERS/ENTERTAINMENT:United Artists TheatersLone Star AmphitheaterLate Show With David

LettermanAlanis MorissetteCraig ChaquicoOprah Winfrey ShowGrand Ole OpryL.A. Shakespeare FestivalTavern on the GreenRicky Van Shelton BandUp With PeopleVienna State Opera Willie NelsonWaylon JenningsHoward Page (Bee Gees

FOH Engineer)Steve Miller BandHollywood CasinoCairo Opera HouseDisneyland’s TomorrowlandJeff Carson BandFox Studios

HOTELS:Hyatt Regency San

FranciscoDebbie Reynolds HotelThe Sands HotelLuxor HotelMarco Island Marriott

SPORTS ARENAS:Jacksonville Jaguars StadiumLambeau Stadium, Green BayShea StadiumOrlando ArenaGateway ArenaCitrus BowlRose BowlTampa SundomeNational Bowling StadiumOlympics 1998 (Nagano)Olympics 2000 (Sydney) Redskins StadiumBaltimore Ravens Stadium

GOVERNMENT:NASAU.S. District CourtThe PentagonAustralian Federal ParliamentUnited Nations HeadquartersNavy’s Sea Lift VesselsPolice Headquarters, NYMARTA System, AtlantaR.A.I. Congress CentreU.S. Federal CourthousesChurch House, WestminsterTien An Men Square 50th

Anniversary of the PRCGovernment Hall (Honduras)Congress InnsbruckPennsylvania State

Supreme CourtSaskatchewan Legislature

CHURCHES:The VaticanCrystal CathedralSt. Mary’s CathedralGrand Mosque (Mecca)Grand Mosque (Oman)Baylake United Methodist

ChurchGolden Era A/V FacilityDaytona Beach Assembly Hall

of the Jehovah’s Witnesses

EDUCATION:Ohio UniversityUniversity of New OrleansUniversity of Michigan

Westin Bonaventure HotelCrown Plaza Hotel

BROADCAST:TNNABC Studios CBS StudiosNBC Studios L.A.Austrian Federal BroadcastCity TV, TorontoWDUZ RadioWRKO RadioKorean Broadcast System

CONVENTION CENTERS:Jacob Javitz Convention

CenterMeadowlands Exposition

CenterMetro Portland Convention

Center

CORPORATE SOUND:Walt Disney CompanyHewlett PackardAmerican Stock ExchangeSea WorldUniversal StudiosMicrosoftBoeing Test LabsWendy’s RestaurantsBusch GardensDave & Buster’s RestaurantsQuantum ResearchDon Cesar Beach Resort

SOUND COMPANIES:Sounds Great EnterprisesWigwam-U.K. (Spice Girls)Sound ServicesShowcoRock ‘n’ Road AudioWavelength Hire Co.Sound Planning

...And thousands more!

Sabine, Inc. • 13301 Highway 441 • Alachua, FL 32615-8544 • 904.418.2000 • Fax 904.418.2001 • www.SabineUSA.com

FBX and FBX Feedback Exterminator are registered trademarks of Sabine, Inc., and are the brand names of its line of automatic feedback controllers.Covered by US Patent No. 5,245,665, Australian Patent No. 653,736, Canadian Patent No. 2,066,624-2, German Patent No. 69118486.0, and U.K. PatentNo. 0486679. Other patents pending. © 1999 Sabine, Inc.

You’re in good company whenyou use Sabine FBX Products

Positive-Feedback-v2.qxd


Positive-Feedback-v2.qxd 6/30/99 11:18 AM Page 1 Version 2 ... · Version 2 ™...

Documents

Transcript of Positive-Feedback-v2.qxd 6/30/99 11:18 AM Page 1 Version 2 ... · Version 2 ™...