How to transcribe a lecture

Check the rules first

Universities, conference organisers, and training providers each set their own rules about recording, and they are not the same. Some departments permit it for personal study only; some lecturers ask to be asked; some sessions are off-limits entirely because of the material being discussed.

Ask the lecturer directly, before the session. It takes one sentence, it is almost always granted for personal study, and it removes the possibility of having recorded something you cannot use.

Getting audio the transcriber can work with

Transcription accuracy is decided mostly at the microphone. A device on the desk in the third row will produce a much better transcript than the same device in your bag, and both will be beaten by sitting nearer the front.

Large rooms are the hard case: reverberation smears consonants, which is precisely what a recogniser needs. If the lecture is amplified, sitting near a speaker often helps more than sitting near the lecturer.

• Sit forward if you can; distance costs more accuracy than anything else
• Put the phone on the desk, screen up, not inside a bag or pocket
• Avoid placing it on a surface that vibrates or that people knock
• Check the battery — an hour of recording plus transcription is not free

What accuracy to expect

General speech in reasonable conditions transcribes well enough to read fluently. Errors concentrate in three places, and they are the three places that matter in a lecture: technical terms, proper nouns, and numbers.

That pattern is predictable, so plan for it. A single correction pass over the recurring terminology, done while you still remember the lecture, is worth more than any amount of careful reading later — a misheard term repeated forty times will otherwise defeat every search you run.

Capture the slides as well

The transcript carries the reasoning; the slides carry the structure, the diagrams and the numbers. A transcript alone will contain phrases like "as you can see here" that point at something you no longer have.

Photograph slides as they appear and run text recognition on them, so the slide text sits in the note next to the passage that discussed it and is searchable with everything else.

Reduce it the same day

A transcript is not a revision note, and the gap between them is where most of the value is either created or lost. An hour of speech should end up as somewhere between half a page and two pages, and the act of deciding what to cut is a substantial part of the learning.

Let AI produce a first summary if you like, but read it against the transcript and cut it yourself. A summary you accepted without checking is one you neither trust nor remember.

• Summarise, then cut the summary in half
• Write the key definitions in your own words
• Keep the transcript underneath for the passages you may need verbatim

Key points

• Ask permission before recording — rules differ by institution and lecturer.
• Sit closer; microphone distance affects accuracy more than any setting.
• Correct recurring technical terms early, before they poison your searches.
• Reduce the transcript to notes the same day, and do the cutting yourself.