Can a designated gift be considered a tithe?

As Christians, we are called to give a tithe (10%) of our income to the Lord.
Leviticus 27:30 (NIV) “A tithe of everything from the land, whether grain from the soil or fruit from the trees, belongs to the LORD; it is holy to the LORD.

For those who might argue that a tithe is not actually 10% I suggest Leviticus 27:32 (NIV) “The entire tithe of the herd and flock—every tenth animal that passes under the shepherd's rod—will be holy to the LORD."

But my focus is not on the percentage given but whether designating the gift to a specific project, event, activity would still qualify it as a tithe.

We are to freely give our tithe to the storehouse (the church) Malachi 3:10 (NIV) "Bring the whole tithe into the storehouse, that there may be food in my house...."
But if the gift is designated or specified how it is to be used (i.e., to buy a new piano, for the building fund, to support a specific mission project, etc.) and not given to the general expenses of the church, can it be considered a tithe? A designated/specified gift comes with a string attached. A string called personal control.

Isn't a designated gift just another method for the giver to decide how God is to use the money? Is such a gift in the spirit of a tithe where the first fruits are to be brought into the storehouse?
I am challenged to find a Biblical example of a designated gift being considered as a tithe. Perhaps I just haven't researched with enough diligence.

In my review of the scriptures it appears to me that a designated gift would better fit under the category of an offering - something given in excess of a tithe. But the tithe - the first 10% is to be given to the church for the leadership anointed by God to determine its use.
I hope this causes you to question your own giving to the church. I welcome the thoughts of others on this issue and encourage the use of scripture to validate your point.

Blessings,