PhD Researcher · Sound Recording · McGill University

Mat
Vallejo

Interdisciplinary audio researcher at McGill University.

Montréal, QC Salt Lake City, UT CIRMMT · IMLab

I'm a researcher and engineer working at the intersection of spatial audio, signal processing, machine learning, and psychoacoustics. My work aims to make spatial audio systems smarter, more perceptually accurate, and more human.

My thesis research, SPIRAL: Spatial Impulse Response Archive for Learning, is geared towards developing a large-scale, publicly available dataset of Spatial Room Impulse Responses designed specifically for training deep learning models. By pairing high-resolution acoustic measurements with architectural, visual, and perceptual data, I'm building the foundation for a new generation of perceptually informed virtual acoustic systems.

My path here winds through a lifelong love of music and audio, professional guitar playing, mixing & mastering, and two graduate music technology programs — every step deepening my conviction that the best audio technology is grounded in how humans actually hear.

AffiliationMcGill University · IMLab
DepartmentMusic Research · Sound Recording
Research centreCIRMMT
FocusSpatial audio · Deep learning · Psychoacoustics
Industry interestMeta Reality Labs · XR audio
TeachingMUSR 200 & Electronics TA
Active — PhD Thesis

SPIRAL

SPATIAL IMPULSE RESPONSE ARCHIVE FOR LEARNING

Thesis research centered around developing a large-scale, publicly available dataset of Spatial Room Impulse Responses (SRIRs) built with high-resolution ambisonic measurements across a diverse range of acoustic environments — concert halls, studio control rooms, lecture theatres, classrooms, etc. Paired with architectural, visual, and perceptual data for multimodal deep learning applications in spatial audio.

SPIRAL addresses the single most significant bottleneck restricting deep learning's potential in spatial audio: the absence of a robust, standardised SRIR dataset. Measurements are taken with the EM64 spherical microphone array at McGill's Immersive Media Lab, capturing a standardised 15×15 grid (225 B-format recordings per space) and used to train a variety of deep learning models.

Dataset Higher-Order Ambisonics EM64 Array Acoustic Measurement Deep Learning CIRMMT · IMLab
// project stages — patch signal flow
01
Measurement campaign & SPIRAL dataset
02
SPIRAL-Net development & pre-training
03
Perceptual evaluation — MUSHRA
04
Full model testing & use-cases
In Development

SPIRAL-Net

MULTIMODAL DEEP LEARNING FOR ACOUSTIC-PERCEPTUAL CROSS-MODAL RETRIEVAL

A hybrid CNN/MLP architecture that learns high-dimensional mappings between measurable acoustic features and human perceptual qualities — immersion, clarity, warmth, envelopment, and more. The full model supports cross-modal queries: input a photograph of a room, a text descriptor like "warm and spacious," or room dimensions, and retrieve a perceptually appropriate spatial impulse response.

PyTorch CNN · MLP Spectrogram Analysis Cross-modal Retrieval ITU-R BS.1534-3 Digital Research Alliance of Canada
Published · AES 157th Convention · 2024

Ambisonic Spatial Resolution Study

INVESTIGATION OF FIRST- AND HIGH-ORDER AMBISONICS FOR AURALIZATION

Investigation of the spatial resolution characteristics of first- and higher-order ambisonic microphones as capturing tools for auralization of real spaces in recording studios equipped with virtual acoustic systems.

Ambisonics Auralization Virtual Acoustics AES 2024
// gain staging
Spatial
Audio
Multichannel, binaural & ambisonic recording
HOA encoding / decoding
SRIR capture & processing
Binaural auralization & HRTF processing
Reverb convolution & rendering
Code &
DSP
MATLAB — signal processing & analysis
Python — PyTorch, TensorFlow, Librosa
C++ - Working Knowledge
Filter design & time-frequency analysis
Beamforming & adaptive filtering
Acoustic feature extraction pipelines
Machine
Learning
Model design and training
Multimodal deep learning architectures
Cross-modal retrieval systems
Dataset curation & preprocessing
K-fold validation & performance analysis
Psycho-
acoustics
MUSHRA listening test design
Statistical analysis of perceptual data
Bias control and test validation (ITU-R BS.1534-3)
Perceptual evaluation of virtual acoustic environments
Spatial imaging, localization & externalization evaluation
2025 – Present
Student Coordinator (RA1)
CIRMMT — McGill University
Support interdisciplinary research and events for Research Axis 1: Instruments, Devices, and Systems. Facilitate collaboration across acoustics, DSP, instrument design, immersive systems, and interactive music technologies.
2024 – Present
Course Instructor — Audio Fundamentals
McGill University
Lead lecturer for MUSR 200, an undergraduate seminar with 60+ students. Develop and maintain course materials for in-depth treatment of audio engineering theory.
2024 – Present
Research Assistant — Virtual Acoustics Technology
Immersive Media Lab (IMLab) · McGill University
Conduct acoustics research on Virtual Acoustics Technology (VAT). Develop and maintain virtual acoustics recording studio systems including software development, impulse response capture, hardware calibration, and auralization best practices.
2024 – Present
Teaching Assistant — Electronics
McGill University
Support undergraduate and graduate coursework in analog electronics. Guide students through circuit analysis, design theory, and practical implementation.
2022 – 2023
Sound Designer — Graduate Fellowship
Earth Moments · London, UK
Compiled and processed audio samples for music production libraries. Developed creative effects chains in Ableton Live, Logic Pro X, and Kontakt.
2021 – 2023
Mixing & Mastering Engineer
Pleasure Craft Studios · Montréal
Mixed and mastered across musical styles in stereo, multichannel, and Dolby Atmos formats.
Ph.D., Sound Recording
McGill University
2023 – Present · Montréal, QC
M.M., Music Technology
Berklee College of Music
2021 – 2022 · Valencia, Spain
Diploma, Music Engineering
Berklee College of Music
2019 – 2021 · Boston, MA
B.A., Economics
University of Puget Sound
2010 – 2014 · Tacoma, WA
AES Convention · 157th · New York · Oct 2024
Investigation of spatial resolution of first and high order ambisonics microphones as capturing tool for auralization of real spaces in recording studios equipped with virtual acoustics systems
G. Grazioli, J. Kelly, M. Vallejo, R. King, W. Woszczyk — Audio Engineering Society Convention Express Paper

// further publications in progress — SPIRAL dataset & SPIRAL-Net architecture papers forthcoming

Let's talk
audio.

I'm interested in research collaborations, industry opportunities in XR audio and spatial sound, and conversations about anything signal processing, acoustics, pyschoacoustics, or machine learning.

I'd love to hear from you!