An alternative to the General-Purpose filter, the Text-In block lets you set parameters using text fields, without having to open another window. The algorithms are the same, giving access to the wide variety of 2nd-order-filter behaviors, although not all the algorithms are offered with Text-In.
See the General 2nd Order Algorithms page for information about the algorithms driving these blocks. The available filters are:
To use this block:
As with other blocks, there's the option to either Grow or Add to this algorithm. Observe that with this block, growing the algorithm adds another frequency band to the block, which is equivalent to having two filters in series. Adding an algorithm adds another input/output pair to the block, which is equivalent to adding a filter in parallel.
The behavior of this block in terms of growing and adding algorithms is like the other filter blocks. A special version of this filter, the Text-In (linked) (which see), forces added algorithms to share the same parameters, and grown algorithms must add a corresponding parallel algorithm. In other words, it allows simultaneous control of added algorithms, and when you grow upon an added algorithm, a corresponding parallel filter will be added to match any previously added algorithm.