The phrase "instrumental only" is correct and can be used in written English.
It is typically used to modify a noun or noun phrase and means that something or someone is only using an instrument (such as a tool or skill) to achieve a desired outcome. Example: The band's performance was instrumental only, with no vocals or lyrics. Example: The new program aims to promote learning through instrumental only activities, such as music and art.
The update provides users with instrumental-only soundtracks to use in their videos.
"Building a Mystery" snatched the Grammy Award for Best Female Pop Vocal Performance, while the instrumental-only song "Last Dance" won the Grammy Award for Best Pop Instrumental Performance.
What an oddity Public Service Broadcasting are: the trio (Mr B controlling visuals, Wrigglesworth on drums, J Willgoose Esq on stringed instruments and electronics) look like fans straight from a Doctor Who convention; and their music is entirely instrumental, the only voices coming from samples of public information and propaganda films.
This deliberation might be merely instrumental, concerned only with settling on means to moral ends, or it might be concerned with settling those ends.
DDR appears to be instrumental not only in the establishment, but also in the maintenance of several aspects of the senescence programme (Fig. 1).
Commodity fetishism is instrumental not only to increasing mainstream fashion sales but also to rejuvenating and multiplying city images on the global competitive market.
That sort of interaction, the team believes, was instrumental not only in the collapse of the twin towers, but of 7 World Trade Center, a 47-story office building at the northern edge of the site.
As they step down this summer, the pair will leave what some in government worry may be a power vacuum, after a period in which an aggressive hand from Mr. Tenet and Mr. Pavitt has proven instrumental not only in directing the agency's own efforts, but in forging cooperation among disparate and rival departments involved in the fight.
Apparently, decision-makers recognize that these attributes are likewise instrumental not only in the smooth, orderly, and efficient conduct of flights but also in the long-term effects of the overall air transportation system.
