Numbers 10:7

When the assembly is to be gathered, you shall blow [the trumpets in short, sharp tones], but without sounding an alarm.

Joel 2:1

Blow the trumpet in Zion [warning of impending judgment],
Sound an alarm on My holy mountain [Zion]!
Let all the inhabitants of the land tremble and shudder in fear,
For the [judgment] day of the Lord is coming;
It is close at hand,

Numbers 10:3-4

When both are blown, all the congregation [that is, all adult males] shall gather before you at the doorway of the Tent of Meeting (tabernacle).

Treasury of Scripture Knowledge

Summary

But when the congregation is to be gathered together, ye shall blow, but ye shall not sound an alarm.

Ye shall blow

Sound

Bible References

Ye shall blow

Numbers 10:3
When both are blown, all the congregation [that is, all adult males] shall gather before you at the doorway of the Tent of Meeting (tabernacle).

Sound

Joel 2:1
Blow the trumpet in Zion [warning of impending judgment],
Sound an alarm on My holy mountain [Zion]!
Let all the inhabitants of the land tremble and shudder in fear,
For the [judgment] day of the Lord is coming;
It is close at hand,