Wordplay for Phoneticians

Following is a rebus-like variation of a well-known idiom. Can you guess what it is?

ull ou all the sos.

Here is a pictographic hint.

And the answer is:

Pull out all the stops.

In phonetics, a stop is a sound that is made by completely stopping and then releasing airflow in the vocal tract. The first version of the idiom in this post is written without the alphabetic letters that represent the stop sounds.

These are the sounds that the IPA classifies as stops: /p,b,t,d,k,g/.

The idiom "pull out all the stops" is defined by thefreedictionary.com as:

"to do everything you can to make something successful."

The Phrase Finder notes on the origin of the phrase include:

"The popular belief is that this phrase derives from the manner of construction of pipe organs. These instruments have stops to control the air flow through the pipes and pulling them out increases the musical volume. This seems to be the type of casual easy answer that is the hallmark of folk etymology. In this case, the popular belief isn't a fallacy but is in fact correct."

Etymologically, this idiom has more to do with phonetics than the uninitiated might picture at first glance.