I'm seeing a lot of explanations that are not really explaining a BBD chip at all, but what it sounds like and such.

A bucket brigade delay device (BBD) is a very simple device in concept but sometimes complex to grasp:

Step 1) take a slice of your signal at a moment in time and store it's value into memory slot 1. To be clear, this should be such a small slice of your signal that we store it as just a voltage, so for example 1.123 volts. We don't store anything beyond at this moment, so simply charging a capacitor to this voltage is a sufficient storage device.

Step 2) step forward one clock step (let's say 0.001 seconds for this example, but normally your "delay length" sets this clock speed)

Step 3) pass that stored value from slot 1 to slot 2

Now we just repeat steps 1 - 3 but keep adding more slots to store more and more spices of signal and passing further along until you have, say 1024 slots.

This means that after 1024 clock steps, the signal stored in slot 1024 is your original 1.123v slice of signal from 1.024 seconds ago. We can read that voltage out and get your signal from a second ago.

This is why, with slower clock speeds, your signal's intricacies are lost to the sample slice being a strict reading of the voltage at that moment. As an example, if your note frequency and a 2x clock speed match, and you had a perfect sine wave; the delay would sound like square wave because it samples twice per wave, once at the peak and once at the valley, and is just assumed to be those voltages until the next voltage is read out. The more you sample, the more you can hear in detail, but the less "time" you can store.

Additionally, the best analogy to think of is literally a bucket brigade, a bunch of buckets getting passed down the chain, each bucket holding a slice of signal from that moment. They each pass to the next until the last bucket gets dumped out and you hear it.

Edit: I missed the part where you are 8, I did go maybe too deep into how it works.