The Feedback Challenge for Acoustic Acts
Folk and acoustic music thrives on intimate, natural sound. However, when playing on festival stages from Newport to Cambridge, even gentle acoustic acts need amplification – and with it comes the risk of that dreaded high-pitched squeal or low rumble of feedback. Unlike loud rock shows where monitors can overpower everything, acoustic performances demand clarity at lower volumes. A single burst of feedback can shatter the atmosphere of a soulful ballad. It’s a challenge every festival organizer faces: how to provide performers with the sound they need on stage without inviting feedback.
Acoustic instruments (guitars, fiddles, banjos, mandolins and the like) and folk vocals often use sensitive microphones and pickups to capture every nuance. These same mics can easily pick up monitor speakers or ambient noise and feed it back into the system. The result is a feedback loop – something to avoid at all costs. The key is a thoughtful stage monitoring approach tailored for acoustic acts. Seasoned festival producers around the world – from small town folk gatherings in Canada to major folk festivals in Australia – have developed techniques to make stages essentially feedback-proof while keeping artists comfortable. Let’s explore these hard-earned best practices.
Separate Vocal and Instrument Monitor Mixes
One fundamental strategy is separating the monitor mixes for vocals and instruments. Instead of sending the exact same monitor mix to every wedge on stage, differentiate between what vocalists and instrumentalists hear. Why? Each has different needs and feedback sensitivities:
– Vocal monitors: Vocalists typically need to hear their own voice prominently, along with some supporting instruments for pitch reference. By dedicating one or more wedges primarily to vocals (with vocals high in that mix and instruments kept lower), you can keep the vocal mics’ monitor volume under tighter control. This reduces the risk that a vocal microphone “hears” its own voice blaring from a nearby instrument monitor.
– Instrument monitors: Likewise, instrumentalists (guitarists, fiddlers, percussionists, etc.) may prefer a separate mix emphasizing key instruments (like rhythmic elements or a lead instrument) and some vocal for timing, but not an overpowering amount of vocals. Their instrument pickups or mics are often lower output than vocals, so these sources can usually be given a monitor mix that doesn’t need to be as loud, or is focused on specific instruments.
By providing multiple monitor mixes – for example, one dedicated to vocals and another to instruments (or even individual mixes per musician if the setup allows) – each monitor can be optimized. This means no single wedge has to be screaming loud to satisfy everyone, which in turn keeps overall stage volume down. For instance, at a folk festival in Spain, the sound crew might give the lead singer a personal front wedge with mostly their vocals and guitar, while the fiddler and bassist share side wedges that carry more of the fiddle, bass, and a touch of vocals. This approach ensures each performer hears what they need and little more, preventing the common scenario of “turn everything up” that often precedes feedback.
Case in point: A veteran sound engineer from a Celtic festival in Canada recalled that earlier in his career, he sent the same monitor mix to all four wedges on stage. The vocalist kept asking for more voice, the fiddler wanted more fiddle, and so on – resulting in all monitors being cranked up and multiple feedback squeals throughout the set. In later years, he switched to separate mixes: the singer got a dedicated vocal wedge and the band had their own instrument-heavy mix. The stage volume dropped dramatically and feedback incidents nearly vanished. The band members could still hear each other, but now each source wasn’t competing with all others in every monitor.
Keep Stage Volume Low
Keeping the stage volume as low as possible is perhaps the golden rule of acoustic performance sound. High stage volume (whether from loud monitors, instrument amplifiers, or even enthusiastic foldback from the main PA) is the enemy of a clean folk sound and a friend to feedback. Here’s how an event team can tame stage levels:
– Use only the volume you truly need: Work with performers during soundcheck to find the minimum monitor level at which they are comfortable. It’s tempting for each musician to ask for more of everything in their monitor “just to be safe,” but experienced festival crews know this often leads to a muddy stage and increased feedback risk. Remind artists that lower stage volume will actually improve what they hear (less clutter and no howling noises). Many professional folk artists understand this; a gentle discussion during soundcheck can align everyone on the goal of clarity over raw volume.
– Minimize open microphones and extraneous sound: The fewer live mics and loudspeakers active, the lower your cumulative stage noise. Mute any microphone that’s not in use (for example, if a performer steps away from a mic for a song, or an unused drum mic during an acoustic tune) to cut down on open channels that can feed back. Also, avoid pointing instrument amps or monitors at stray microphones. If an acoustic guitarist uses a small amp or an on-stage acoustic amplifier, treat it like a mini monitor – aim it at the player’s ears, not at the crowd or other mics. Keeping sound sources directed and contained helps maintain a lower effective volume on stage.
– No “volume wars” on stage: In electric bands, sometimes each member turns up louder than the others, causing a spiral of volume increases. In acoustic settings, this can happen too – a loud monitor for the vocalist might prompt the banjo player to ask for more banjo in theirs. Soon everyone’s too loud. An alert monitor engineer or stage manager should keep this in check. If one monitor mix is raised significantly, try to bring other mixes down rather than pushing everything up. It’s a balancing act requiring diplomacy and clarity with the musicians.
A lower stage volume yields multiple benefits: microphones are less likely to pick up sound from monitors (hence reduced feedback), performers can actually hear the nuances better, and even the audience hears a cleaner mix (bleed from stage to audience is reduced). Many large folk festivals, such as those in Australia and New Zealand, enforce strict stage volume limits for this reason – not just to satisfy noise regulations but to preserve audio quality. Even indoors, say at a folk club in India or an acoustic hall in Germany, prudent sound crews keep monitor levels moderate.
Real-world example: At a well-known folk festival in the UK, a bluegrass band once struggled with constant feedback during their set. Post-mortem analysis revealed that every musician had asked for nearly every instrument in their wedge at high volume, essentially creating a mini-PA system on stage. The next year, the festival’s audio team adopted a “less is more” approach – each performer only got one or two essential elements in their monitor. The stage sound was noticeably quieter; not a single feedback squeal occurred, and the musicians actually complimented the clarity on stage. They could finally hear just what they needed. This success story highlights that in live sound for folk acts, sometimes turning things down is the key to turning the overall quality up.
Use Cardioid Microphones and Careful EQ-Notching
Another critical piece of the feedback-prevention puzzle is microphone choice and equalization. Acoustic acts often use a range of mics – from vocal mics to instrument condensers – which can be very sensitive. Choosing the right mic and positioning it wisely can dramatically improve gain-before-feedback. Cardioid or hypercardioid microphones (which pick up sound mostly from the front and reject sound from the rear/sides) are preferred on loud stages. Here’s how to capitalize on them:
– Aim the “dead zone” of the mic at the monitors: Cardioid mics like the trusty Shure SM58 pick up very little sound from directly behind. Place floor wedges directly behind such vocal mics (pointing at the singer’s face, with the rear of the mic toward the monitor). This way, the monitor’s output hits the least sensitive part of the mic capsule. For hypercardioid mics (which have a slight rear pickup lobe but more rejection at ~45 degrees off-center), adjust accordingly – often placing monitors a bit to the sides rather than straight back. The technical specs or polar pattern diagrams of your microphones can guide you on the best angles for monitor placement. An attentive stage crew will sometimes even mark the optimal mic orientation on stage or use small mic-stand mounted shields to keep things aligned.
– Cut problem frequencies with surgical EQ: Despite best placement, some frequencies will naturally want to ring out (feedback) due to room acoustics or the characteristics of instruments and mics. Using EQ-notching means identifying those “hot” frequencies and reducing them slightly in the monitors. Typically, the monitor engineer will “ring out” the wedges before or during soundcheck: gradually raising the monitor gain until a particular frequency starts to feed back, then pulling that frequency down on the graphic EQ or parametric EQ for that monitor send. By doing this systematically, you carve out a safer operating range. For instance, you might find Stage 2 at your festival tends to get boomy feedback around 250 Hz (common with guitar body resonance) and squeals around 3 kHz – those bands can be notched a few dB to give more headroom. It’s wise to log these problem frequencies (more on logging later) so you can anticipate them in future performances.
– Use high-pass filters liberally: Most acoustic instruments and vocals don’t have useful sound in the very low frequencies (for example, below 80 Hz). By applying a high-pass filter (low-cut) on each mic channel for stage monitors, you remove sub-bass rumble that often triggers feedback or muddy build-up. This is standard practice especially for vocal and instrument mics – set the high-pass filter to a point that filters out stage thumps or wind noise (if outdoors) but doesn’t thin out the instrument’s tone. Cutting out that unnecessary low end means the monitors won’t amplify it, giving you more clarity and less chance of low-frequency feedback (that “woofy” sound which can happen with acoustic guitars or mics in hollow stages).
– Mind the EQ boosts – usually, less is more: In monitor mixes, it’s usually safer to cut frequencies than to boost. Any EQ boost is effectively increasing the gain at that frequency, potentially walking closer to feedback. If an artist wants “more warmth” or “more sparkle” in their monitor, try to achieve it by cutting other bands (or better mic placement) rather than cranking up bass or treble.
When equalizing, do it monitor by monitor since each wedge or each instrument mic might have different trouble spots. Digital consoles nowadays often have feedback-detection tools or automatic notch filters – these can help in a pinch, but nothing replaces an experienced ear. An old trick used by festival sound crews in places from Mexico to Singapore is to carry a list of typical troublesome frequencies for common microphones and instruments (for example, many acoustic guitars tend to feedback around the open A string ~110 Hz or the D ~147 Hz, and some fiddles around certain high mid frequencies). During soundcheck, they pay special attention to these areas, ready to notch down if needed.
Finally, remember that mic technique and stage setup also play a role. If a singer is wandering far off the mic or cupping their hand over the mic head, or if an instrument mic is too far from the source, you’ll need to crank the gain – a recipe for feedback. Encourage performers (through gentle coaching, if possible) to stay close to their mics and not obstruct the mic’s grille. Many folk artists, especially newer ones, might not be aware how dramatically these habits affect feedback. A quick friendly note during soundcheck – for example, advising a singer who tends to “drift” from the microphone – can save a lot of trouble during the show.
Offer In-Ear Monitors (IEMs) for Sensitive Artists
In-ear monitors can be a game changer for controlling stage sound, and many modern artists are adopting them. Instead of floor wedges blasting sound openly, IEMs deliver a personal mix directly to the performer’s ears via earbuds, eliminating the monitor speaker from the equation (and thus removing a major feedback source entirely). For acoustic acts and folk singers who are particularly sensitive to loud stage noise or who want pristine clarity, offering IEMs is a smart option:
– Drastic feedback reduction: With all (or most) monitors moved off the stage and into performers’ ears, there are far fewer open speaker-to-microphone paths that can cause feedback. This is why some big touring acts run completely “wedgeless” stages. At large international folk festivals – from the U.S. to Japan – headlining artists increasingly carry their own IEM systems. If the budget and tech infrastructure allow, a festival should accommodate this or even provide a basic wireless IEM setup for artists who request it. The payoff is a virtually feedback-free stage monitoring environment.
– Lower overall stage noise: Not only do IEMs nix feedback, they also drastically cut stage volume, which helps keep the acoustic vibe clean. Performers can have as much of themselves or others in their mix as they want without any speaker noise spilling into microphones. For example, a sensitive singer-songwriter in France might prefer IEMs so she can have her vocal and guitar high in her ears without her microphone picking up a loud wedge. Meanwhile, the acoustic bassist on the other side of the stage doesn’t have to suffer the bleed of her monitor – because it’s in her ears only.
– Artist comfort and performance: Some artists simply perform better when using IEMs, since they can hear details and pitch more accurately. This can especially help those who sing in harmony or need to lock in with intricate instrumental parts. Additionally, folk musicians often swap instruments or move between lead and backing roles; with IEMs, they can ask the engineer for a more nuanced mix (perhaps adding more fiddle in the chorus when the fiddle takes a lead) that would be impractical to blare via wedges mid-song.
That said, not every artist will want IEMs. It’s important to offer but not force them. Some traditional folk performers find IEMs isolating – they miss the natural “room feel” or audience connection. One compromise is to use IEMs for certain band members (for instance, the ones most bothered by loud sound or most at risk of feedback, like vocalists with powerful mics), while still using a couple of floor wedges for others who prefer them. If doing this, keep a careful balance: even one or two wedges on stage mean you must still manage those like any monitor to prevent feedback. But overall, having half the band on IEMs can markedly reduce how loud those remaining wedges need to be.
For festivals, a practical tip is to keep a set of universal-fit IEMs and wireless packs ready for artists who decide last-minute that they’d like to try in-ears. It’s also wise to have an IEM-savvy monitor engineer around – mixing IEMs requires paying attention to stereo panning, adding a touch of ambient audience mic feed (so the performer doesn’t feel like they’re playing in a vacuum), and safeguarding against sudden loud sounds (with limiters, since a feedback squeal directly in the ear is dangerous). When done right, however, IEMs can deliver an immaculate on-stage experience. Many a folk singer with a delicate voice has been relieved to discover they no longer need a blaring wedge at their feet to hear themselves.
Screens and Gobos: Contain Sound Without Killing Sightlines
Physical acoustic control can be your ally in fighting feedback. Screens and gobos are tools used to block or absorb sound on stage. They can prevent, for example, a loud source from bleeding heavily into a microphone. In a folk or acoustic context, you might not have massive guitar amps or drum kits like a rock show, but even modest setups can benefit from strategic use of screens:
– Transparent screens (acrylic shields): These are commonly seen around drum kits, but they can also be used on a smaller scale for acoustic acts. A clear acrylic screen placed between a monitor speaker and a sensitive microphone (or between a percussion setup and the rest of the stage) can deflect sound away from the mic’s direct path. Because it’s transparent, it preserves sightlines – the audience can still see the performer, and band members can see each other. Use these sparingly for problem areas: for instance, if a fiddler’s mic is picking up too much from the guitarist’s monitor, a small acrylic panel between them might do the trick.
– Gobos and portable baffles: “Gobo” is a studio term (short for “go-between”) for movable sound-absorbing panels. On stage, gobos could be folding acoustic panels, padded boards, or even heavy theater drapes hung in strategic spots. At a festival in Indonesia, for example, the engineers might place a couple of narrow absorption panels on either side of a harp player to block the monitor sound from a nearby speaker stack. The key is to reduce unwanted sound traveling to microphones without making the stage look like a maze of walls. Low-profile gobos – say, waist-high panels on the stage floor – can soak up monitor sound energy but remain mostly out of the audience’s view. Likewise, a gobo on the floor in front of a floor wedge can help absorb some of its output before it bounces into a mic.
– Placement and aesthetic considerations: Always walk to the audience perspective (and the performers’ positions) to double-check that any screen or gobo you place isn’t blocking the view. Folk festivals celebrate connection and transparency; you wouldn’t want a barricade of panels making the audience feel separated from the artists. Opt for clear materials or those with a decorative design if visible. Sometimes, festivals incorporate local art or banner cloth on gobo panels so they blend into the stage décor. This way, you achieve acoustic isolation while even adding to the vibe.
One must also be aware that adding screens can alter acoustics (sound can reflect off acrylic back toward the stage or ceiling). Therefore, use them judiciously and test during soundcheck if a screen is helping or perhaps causing a weird echo. Often the benefit – stopping a direct feedback path – outweighs a minor reflection. Communication with performers is vital too: if you’re going to place a shield near a musician, explain that it’s to improve their sound. Most folk artists will appreciate the thought, as long as they can still see the audience and each other.
Log Problem Frequencies and Solutions for Each Stage
Every stage and venue has its quirks. An experienced festival organizer knows that knowledge accumulates year to year – and it’s wise to write it down. Keeping a log of problem frequencies and feedback issues for each stage can save precious time when the pressure’s on. Here’s how effective logging and preparation works:
– Venue-specific frequency notes: Suppose on the “Meadow Stage” last year (an open-air stage under a tent in a field in California), you noticed a persistent low-mid feedback around 180 Hz whenever acoustic guitars played loud. At the “Barn Stage” (an indoor wooden hall in Scotland), maybe the combination of wooden walls caused a ringing at 500 Hz with certain fiddle mics. These observations should be recorded after the event or during rehearsals. Next time you set up in the same stage, you can proactively dial down those frequencies a notch on the monitors or be extra vigilant during soundcheck.
– Equipment and configuration notes: Include in the log what microphones, monitor speakers, and positioning were used when problems occurred or were solved. For example, “Stage 2: switched vocal mics from condenser to dynamic to stop 2 kHz feedback on windy day,” or “Stage 1: feedback on main vocals solved by reducing monitor #3 level and HPF at 100 Hz.” These breadcrumbs help future sound teams, especially if staff change or if another engineer takes over. It’s like leaving a recipe for success (and a warning of past pitfalls).
– Environmental factors: It’s not just the gear – note the environment. Outdoor stages can behave differently at different times of day. A calm afternoon might pose no issues, but as humidity rises at night or the temperature drops, sound can travel differently. In one instance, a folk festival by the coast in New Zealand discovered that right after sunset, certain frequencies would suddenly start feeding back on stage as the air density changed. They logged the phenomenon, and in subsequent nights the engineers pre-emptively adjusted EQ as dusk fell – no more surprise squeals. If you identify patterns like “tent sidewalls flapping in the wind causing low-end rumble” or “empty hall vs. packed crowd changes the acoustics dramatically,” write it down and plan for it.
– Continuous improvement: Treat each festival or show as a learning opportunity to refine your feedback-fighting playbook. Some festivals hold a brief post-event debrief with the audio crew—part of that meeting can be reviewing any feedback issues and how they were resolved. Those insights then get added to next year’s planning. Over time, you’ll amass a detailed understanding of each stage’s behavior. New crew members can be handed a document or checklist with pointers like “monitor EQ preset for Stage A” or “watch out for fiddle on Stage B, tends to be hot at 1.2 kHz – notch if needed.”
By logging and learning, festival producers turn feedback control from a reactive firefight into a proactive strategy. It’s a satisfying feeling to walk into a familiar stage with confidence that you already know the trouble spots and have the tools (proper mics, EQ settings, etc.) ready to go.
Adapting to Different Scales and Settings
Folk festivals come in all sizes and settings – from a small 100-person open-mic night in a local pub to international outdoor festivals with tens of thousands of attendees. The core principles of feedback prevention and sound management apply universally, but the scale can introduce different considerations:
– Small-scale, intimate venues: In a cozy folk club or a small community festival stage, you might get away with minimal sound reinforcement. Some acoustic acts even prefer no monitors at all in tiny rooms, relying on natural acoustics. If monitors are used, often it’s just one or two small wedges. Here, the focus might be on simply positioning those one or two speakers smartly and keeping volumes conversational. In very small settings, the best monitor might even be none – if the room is quiet enough, artists can hear themselves naturally. Festival organizers should judge when to forego amplification; sometimes an unplugged performance eliminates feedback risk entirely and creates a special moment. Of course, if you do need that reinforcement, all the earlier tips still hold – maybe you’ll use a single cardioid mic for the band and a single hotspot monitor to lightly fill sound to the back of the stage.
– Large-scale, multi-stage festivals: At the big end (think events like the Philadelphia Folk Festival or Woodford Folk Festival), you’ll have multiple stages with full professional sound systems. More stages mean more gear and more crew, which means consistency becomes key. It’s important to standardize good practices across all stages: ensure every stage’s monitor engineer is briefed on the festival’s philosophy about stage volume and feedback avoidance, and that they have the tools (enough EQ, the right mics, etc.) available. On a large folk stage, you may have many monitors (for example, wedges across the front, plus side-fills for wide stages, plus dedicated subs for certain instruments). The temptation to use all of them at high volume must be resisted. Often the best large stages mimic small-stage ethos: use only as much sound as needed. A famous sound designer once managed a huge folk ensemble on a major festival main stage by turning off half the wedges – the musicians realized they could hear each other fine with just a few monitors once the excess noise was gone.
– Indoor vs. outdoor differences: Many folk festivals mix indoor and outdoor venues. Outdoors, you generally have less reflective surfaces (no walls to bounce sound), which can allow a bit more monitor volume before feedback – but wind and weather can introduce other unpredictabilities (wind noise in mics, or sound blowing around and getting back into microphones from unexpected angles). Indoors, acoustics can be tricky – a boomy hall might feedback at lower volumes because the sound is trapped and reinforcing. As a festival organizer, choose stage locations wisely: for example, if you have a delicate acoustic trio, putting them in a tented stage with lots of draping (which absorbs sound) could be safer than on a concrete plaza that reflects everything. Each environment might require slightly different monitor strategies (like more aggressive EQ indoors, or wind screens on mics outdoors).
– Cultural and regional factors: Internationally, festival producers encounter various cultural performance styles. In some traditional music, performers may be used to minimal amplification or have unique instruments that are hard to mic (e.g., a didgeridoo at an Australian folk event or a sitar at an Indian folk fusion concert). These situations call for flexibility – perhaps you’ll deploy a specialized mic or pickup to get enough volume without feedback, or you’ll place additional gobos to isolate a particularly resonant instrument. Always communicate with the artist; they might have personal techniques for sound (some carry their own preamps with notch filters, etc.). Being respectful of these differences and prepared to adapt your standard methods will earn trust and lead to a better outcome.
No matter the scale or style, the prudent festival organizer always circles back to the core mission: allow the performers to hear themselves clearly and comfortably, with no painful feedback blasts, and without compromising the connection with the audience. It’s a balancing act of art and science – one that improves with each show.
Key Takeaways
- Balance monitors with separate mixes: Use distinct vocal and instrument monitor mixes (or individual mixes) so no monitor has to be excessively loud. This targeted approach keeps feedback at bay and gives performers what they specifically need.
- Lower is louder (in the end): Keeping stage volume as low as practical leads to clearer sound. Avoid the trap of “more me” in every monitor – less overall noise means more clarity and far less feedback risk.
- The right mic and placement matter: Use cardioid or hypercardioid microphones and point their null (least sensitive) spots toward monitors. Proper mic technique and placement can drastically increase gain before feedback.
- Notch out the nasty frequencies: Employ high-pass filters and cut troublesome frequencies in the monitors rather than boosting EQ. Ring out each stage’s monitors during soundcheck and tame any frequencies that start to ring.
- Consider in-ears: In-ear monitors can virtually eliminate feedback by removing loudspeakers from the equation. Offer IEMs especially to artists who are particular about their sound or struggle with wedges.
- Use acoustic shields smartly: Transparent screens or small gobos can block feedback paths between monitors and mics, but position them so they don’t block sightlines or isolate performers from the audience.
- Learn from each show: Keep a log of feedback issues, problem frequencies, and solutions for each stage and act. This accumulated knowledge will make future events smoother and sound better for everyone.
22nd September 2025