Every track points back
to a paper you can read.
We are not asking you to trust us. We are asking you to read the studies. Below is the full reference base — DOIs included — that informs the catalog. Where the evidence has caveats (small samples, replication issues, responder asymmetry), we say so.
Sleep & Rest
3 papersAcoustic Enhancement of Sleep Slow Oscillations and Concomitant Memory Improvement in Older Adults
Papalambros NA et al.
Pink noise pulses synchronized to slow oscillations enhanced slow-wave activity and improved memory consolidation in older adults.
Auditory closed-loop stimulation of the sleep slow oscillation enhances memory
Ngo HV et al.
Closed-loop auditory stimulation in phase with slow oscillations boosted memory consolidation during NREM sleep.
White noise and sleep induction
Spencer JAD et al.
White noise induced sleep in 80% of newborns within 5 minutes vs 25% in controls.
Focus & Work
9 papersThe effects of background white noise on memory performance in inattentive school children
Söderlund GBW et al.
Background white noise improved memory in inattentive children, consistent with the stochastic resonance hypothesis.
Is Noise Always Bad? Exploring the Effects of Ambient Noise on Creative Cognition
Mehta R, Zhu R, Cheema A
Moderate ambient noise (~70 dB) enhanced creative cognition vs low or high noise, via processing disfluency promoting abstract thinking.
Do White Noise or Pink Noise Help With Task Performance in Youth With ADHD?
Nigg JT et al.
Meta-analysis of 13 RCTs: small but significant benefit of white/pink noise on attention in ADHD youth. Same noise impaired non-ADHD performance.
Cognitive performance, creativity and stress levels of neurotypical young adults under different white noise levels
Awada M et al.
White noise at 45 dB outperformed 55/65/75 dB for sustained attention, accuracy, and stress markers in neurotypical adults.
Effects of auditory white noise stimulation on sustained attention and response time variability
Egeland J et al.
White noise reduced reaction time variability in children with elevated ADHD symptoms — moderate brain arousal model.
Background white noise and speech facilitate visual working memory
Han S, Zhu R, Ku Y
Background noise and speech significantly improved visual working memory in neurotypical adults vs silence. Arousal-mediated.
White noise enhances new-word learning in healthy adults
Angwin AJ et al.
White noise improved novel word-meaning recall in adults vs silence. Effect did not depend on baseline attentional ability.
Of cricket chirps and car horns: The effect of nature sounds on cognitive performance
Van Hedger SC et al.
Natural soundscapes improved directed-attention performance vs urban soundscapes — Attention Restoration Theory.
Long-term effects of the use of a sound masking system in open-plan offices: a field study
Lenne L, Chevret P, Marchand J
Field study of a long-term sound masking system in an open-plan office. Masking lowers distant-speech intelligibility below the Speech Transmission Index threshold — the acoustic basis of speech privacy (ASTM E1130/E2638).
Calm & Regulation
11 papersStress recovery during exposure to nature sound and environmental noise
Alvarsson JJ, Wiens S, Nilsson ME
Nature sounds accelerated physiological recovery from stress, measured via skin conductance.
Inducing physiological stress recovery with sounds of nature in a virtual reality forest
Annerstedt M et al.
Nature sounds in VR forest accelerated parasympathetic activation post-stressor (HRV measurement).
Cardiovascular, cerebrovascular, and respiratory changes induced by different types of music
Bernardi L, Porta C, Sleight P
Slow tempo music induced cardiovascular relaxation. Silence between tracks was as relaxing as the music.
More than a feeling: ASMR is characterized by reliable changes in affect and physiology
Poerio GL et al.
ASMR videos reliably reduced heart rate in responders (~20% of population). Non-responders showed no effect.
Sound therapy (using amplification devices and/or sound generators) for tinnitus
Sereda M, Xia J, El Refaie A, Hall DA, Hoare DJ
Cochrane review of 8 trials (590 adults). Sound therapy is mainstream in tinnitus management, but no included trial compared it against a waiting-list, placebo, or education-only control — evidence was low-certainty and did not show superiority over no device.
A synthesis of health benefits of natural sounds and their distribution in national parks
Buxton RT et al.
Meta-analysis (18 of 36 studies): natural sounds were associated with decreased stress and annoyance (g = -0.60, 95% CI -0.97 to -0.23) and improved health/positive affect (g = 1.63, 95% CI 0.09 to 3.16).
Anxiety-reducing effects of natural sounds: a systematic review and meta-analysis
Zhu X et al.
Meta-analysis (15 studies, n=1285): natural sounds significantly reduced anxiety and produced physiological calming (lower heart rate, blood pressure, respiratory rate) vs control.
Birdsongs alleviate anxiety and paranoia in healthy participants
Stobbe E et al.
Randomized experiment: birdsong reduced anxiety and paranoia vs traffic noise; high-diversity birdsong also lowered depressive state.
Bird sounds and their contributions to perceived attention restoration and stress recovery
Ratcliffe E, Gatersleben B, Sowden PT
Birdsong was the natural sound most associated with perceived stress recovery; restorative bird sounds were appraised as positive-valence and low-arousal.
Bright light, negative air ions and auditory stimuli produce rapid mood changes in a student population: a placebo-controlled study
Goel N, Etwaroo GR
Placebo-controlled study (n=118): an auditory stimulus (birdsong layered with classical music) produced rapid positive mood changes.
Hearth and campfire influences on arterial blood pressure: defraying the costs of the social brain through fireside relaxation
Lynn CD
Fire WITH sound lowered blood pressure via parasympathetic activation (effect grew over ~15 min); muted visual-only fire was inconsistent, so the author concluded the SOUND is the active ingredient.
When the evidence moves, we say so.
Citing a paper is not the same as pretending the science is settled. When new, rigorous research complicates a claim we rely on, we publish it here — even when it cuts against us.
Pink noise can reduce REM sleep when used to mask environmental noise
A 2026 sleep-lab study found that adding pink noise to mask traffic and aircraft noise reduced restorative REM sleep and interfered with sleep recovery — earplugs protected sleep better. This does not erase the slow-wave benefits seen in Papalambros 2017 (a different setup: gentle pulses, not continuous masking), but it is a real limit on the "pink noise is always good for sleep" story the niche likes to tell. We surface it, we link it, and we calibrate our overnight tracks accordingly.
Read the study →What we refuse to cite.
Solfeggio frequencies. 432 Hz "natural tuning." Mozart-effect intelligence claims. Binaural beats with strong claims. We have documented why each of these is rejected in our reference base — and we keep that list public, in the open repo.