A bare timer makes one sound, and the bell is it. Everything around it is silence, so the single note that opens and closes a sitting carries more than its small part suggests. ZenFlow ships one Tibetan singing bowl, and for most people one is the entire answer — but it helps to know what you are listening for.

## which bell should you choose?

A standing bell — what most people call a Tibetan singing bowl — struck once and left to ring out. The sound you want is low enough not to startle, clean at the strike, and long in the decay, so that it thins into silence rather than stopping. A good bell does not so much announce the end of the sitting as dissolve into it. The strike matters more than the bowl: struck well, a modest bowl sounds better than an expensive one rung carelessly.

## what the start, interval, and end bells are each for

Three places a bell can fall, and each does a different job.

A start bell marks the threshold. It tells the body that the watching has begun and there is nothing more to arrange — a small ceremony that ends the fidgeting.

An interval bell falls in the middle. It marks time you would otherwise check a clock for, and it can re-anchor a wandering mind without a word. How often to place one is its own question, taken up in [interval bells](/journal/interval-bells).

An end bell closes the sitting. This is the one bell almost everyone keeps. It should arrive softly enough to draw you up rather than jolt you — the difference between being called and being woken.

## the case for one bell

A soundboard of options is a decision you make before every sit, and a sitting is the wrong place to be choosing ringtones. One bell you trust disappears; you stop hearing the app and start hearing the bell. ZenFlow's paid tier adds more bells and custom interval programs for those who want them, but the single bowl it gives away is, for most practices, the whole of what a bell needs to be. Choose one you would not mind hearing every day for a year, and then stop choosing.