Full marks6/6
The sample rate is the number of samples taken each second and is measured in hertz. The sample interval is the time gap between one sample and the next, so it is the reciprocal of the sample rate: a higher rate means a shorter interval. If the school uses a high sample rate, such as 44,100 Hz, the interval between samples is short, so the analogue-to-digital converter measures the concert wave very often and follows its shape closely. This makes the recording more accurate, because quiet details and fast drum beats are less likely to happen between samples and be missed, and high notes from the violins are captured properly. However, every sample is stored using bits, so 44,100 samples each second means much more data for each second of the concert and a much larger file, which could download slowly from the school website. If the school halves the sample rate, the interval doubles, the file is half the size, but fast changes in the music may be missed and the recording will sound less like the live performance, so the school must trade off quality against file size.
Why: Level 3 (6 marks): defines both terms, states the reciprocal link, explains why a short interval gives accurate capture (wave shape, fast changes, high frequencies) and why more samples per second means more data, applies all of this to the concert and the website, and draws a trade-off.
Some marks3/6
The sample rate is how many samples are taken each second. The sample interval is the time between each sample, so a higher sample rate means a shorter sample interval. If the school uses a higher sample rate, more of the concert is measured each second, so the recording is more accurate. A higher sample rate also makes the audio file bigger, which will download more slowly from the school website. The school should not use a sample rate that is too high or the file will be too large.
Why: Level 2 (3 marks): definitions are correct and the reciprocal link is stated, and there is one link to accuracy and one link to file size with some application to the concert, but nothing on why slow sampling misses detail and no mechanism for the file-size increase, so it is adequate rather than comprehensive.
Some marks1/6
The sample rate is the number of bits used for each sample. A higher sample rate gives a more accurate recording, so the school should use the highest sample rate so that the concert sounds just like the live performance.
Why: Level 1 (1 mark): one basic correct point, that a higher sample rate gives a more accurate recording; the definition confuses sample rate with bit depth and is not credited, and no point is made about the file size.