Sparse recordings in, a defensible hemisphere out

Our problems are sourced, not invented. They come from United States and allied special operations units that already own a mission set and need a tool to finish it.

We are hiring a physical acoustics scientist. You will take a sparse set of real field recordings of a real platform and reconstruct its complete acoustic hemisphere, with error bars that a test and evaluation customer will accept. Then you will make the reconstruction methods better than the published baselines.

The work rests on physical acoustics of moving sources: outdoor sound propagation, directivity, Doppler, atmospheric effects. It is not room acoustics, and it is not audio engineering for music.

To retire the named technical risk

One problem carries the program: adapting learned-field methods to the emitter-directivity problem. That is not the published room-acoustics formulation, and the distance between the two is the work. The source moves, the emitter is directional, the environment is unbounded, and the measurements are sparse by design.

The reference point is MIT CSAIL, "Learning Neural Acoustic Fields" (arXiv:2204.00628, 2022). Treat it as a starting formulation, not an answer. Closing the gap between it and our conditions is the named technical risk in the technical thesis, and this hire is the person who retires it.

The judgment calls are yours

1. The source-hemisphere formulation

   Adapting learned-field methods to the emitter-directivity problem, which is not the published room-acoustics formulation. You define the representation, the training regime, and what counts as convergence.

2. The capture methodology

   Microphone geometry, pass profiles, calibration discipline, error budgets. Deciding how sparse a capture can go before accuracy dies, and proving where that line sits rather than asserting it.

3. Digital signal processing (DSP) chain integrity

   De-propagation for spreading and atmospheric absorption, deconvolution, back-propagation to the one meter reference. You own the chain end to end, including the split between chain error and reconstruction error that the current proof of concept self-scores.

4. The validation regime

   Ground truth protocols, uncertainty quantification, honest error bars on every product output. Credibility with test and evaluation (T&E) grade customers rests on your standards, not on marketing language.

5. Propagation modelling

   Terrain and urban effects, and judging when a fast approximation is fit for purpose and when it is misleading. Knowing the difference is the job.

The background the work requires

Required

• A doctorate in acoustics, applied physics, aerospace or mechanical engineering, or equivalent research experience in outdoor or aeroacoustics
• Working command of the physical acoustics of moving sources, including Doppler and the effect of source motion on a measured spectrum
• Demonstrated experience in outdoor sound propagation: geometric spreading, atmospheric absorption, ground effect, and refraction under real wind and temperature profiles
• Practical understanding of source directivity, and how it shifts with operating state and observation angle
• Hands-on field measurement experience: microphone calibration, instrumentation error, and uncertainty budgets you have had to defend to someone who checked
• Numerical modelling ability in Python or an equivalent language, including learned-field or other modern data-driven methods

Preferred

• Prior work measuring the noise of helicopters, propeller aircraft, or drones
• Familiarity with the neural acoustic field literature, including MIT CSAIL arXiv:2204.00628, and with where implicit neural representations of continuous fields break down
• Familiarity with the governing standards: International Organization for Standardization (ISO) 9613 for outdoor propagation, ISO 3744 for sound power, and SAE Aerospace Recommended Practice (ARP) 866 for atmospheric absorption
• Experience running instrumentation at a flight test event or an open-air test range
• Published work where the underlying data and its uncertainty were released alongside the result

To be direct about the fit: this is not room acoustics, not architectural acoustics, and not audio engineering for music. If your measurement experience is indoors and dense, this is the wrong role.

Send a resume. That is the whole application.

No cover letter, no take-home. If you are qualified, we will know it. If we are not worth your time, you will know it.

Every application gets a reply within 72 hours, including the ones that do not move forward.

Research in, a client-ready deck out

Harrison Rider is a defense advisory firm. The mandates are go-to-market strategy, competitive analysis, market sizing, fundraising materials, and the acquisition strategy work that carries a technology company toward a program of record: positioning, partnership frameworks, and the execution plans that follow a contract award.

This hire builds the material every engagement runs on: the market sizing model, the competitive assessment, the research behind a fundraising deck, the deck itself. The analysis and the deliverable are yours.

To carry the analytical workload, not the relationship

Every client conversation at Harrison Rider runs through the firm's principal. What does not scale is the work behind each conversation: the Excel model, the market research, the deck that turns both into something a client can act on. This hire exists to take that work off one person's plate so the firm can run more engagements at once.

Three things, done well

1. Financial and market modeling

   Market sizing, revenue models, and budget and opportunity analysis, built in Excel to a standard someone else can hand to a client without rework.

2. Deck building

   Turning a model or a research finding into a client-ready presentation: the argument, the structure, the slide itself.

3. Research

   Market research, competitive research, and tracking the defense acquisition and policy landscape a client's strategy has to fit inside.

The background the work requires

Required

• Bachelor's degree with a strong academic record; a master's degree or MBA is relevant but not required
• 3 – 6 years building financial models, market sizing, or competitive analysis in strategy consulting, corporate development, investment banking, or private equity, with exposure to the aerospace, defense, or national security sector
• Rigorous quantitative skills in Excel: revenue models, market sizing, and budget analysis, with numbers built to survive someone else checking them
• Strong presentation-building skills: turning analysis into a clean, client-ready deck with minimal direction
• Working knowledge of the Department of War (DoW) acquisition process and the broader national security ecosystem, or the ability to pick it up fast
• Ability to work in the United States without sponsorship now or in the future

Preferred

• Prior experience supporting an aerospace, defense, or government services engagement, in a research or analyst capacity rather than a client-facing one
• Comfort working independently on a small team with no analyst pool behind you
• Experience with the standard defense sector data sources, including SAM.gov and USAspending.gov

Send a resume. That is the whole application.

No cover letter, no take home. This is a remote role, and Harrison Rider is open to full time or part time. If you are qualified, we will know it. If we are not worth your time, you will know it.

Every application gets a reply within 72 hours, including the ones that do not move forward.