What is the meaning of "Kanasti [Li]"?
Ibn Ezra: I gathered [Metzudas David - for myself]. This is like "Lech Kenos Es Kol ha'Yehudim" (Esther 4:16).
What is "Segulas Melachim"?
Rashi: Hidden treasures of kings - gold and gems that kings acquire and hide.
Ibn Ezra: It is something coveted. It is guarded to glorify oneself in it, like kings' jewels, and things that are found only in one country.
Seforno: They are gems and pearls.
Metzudas Tziyon: It is a coveted matter that one hides in a storehouse. This is like "vi'Hyisem Li Segulah" (Shemos 19:5).
What is "veha'Medinos"?
Rashi: The treasures of merchants.
Rashbam: Storehouses of coveted matters of the Medinos; Seforno - e.g. coral wood.
Ri Kara: It is [treasure] that nobles of the country acquire and store.
Metzudas David: It is what the kingdom hides in a storehouse on behalf of all people of the country.
Why does it say "Asisi Li [Sarim v'Saros]"?
Rashbam, Metzudas Tziyon: I prepared for my needs. This is like "u'Ven ha'Bakar Asher Asah" (Bereishis 18:8), "v'Asesah Es Tziparneha" (Devarim 21:12).
Seforno: I made "Sarim v'Saros" (instruments) from Segulas veha'Medinos (coral wood).
Who are "Sarim v'Saros"?
Rashi: They are instruments.
Ri Kara, Metzudas Tziyon, from Koheles Rabah 2:8: Sarim are males, and Saros are females. Ri Kara - both know how to sing with all kinds of instruments.
Michlol Yofi: [Sarim are men;] Saros are boys with high pitched voices. Etz Yosef (on Ein Yakov Gitin 68a) - Shlomo invented the Chachmah of music 1 ; he needed singers with high voices.
Before Shlomo, David specified particular musical instruments to accompany particular Tehilim. However, he did not make a Chachmah from it. (PF)
A man may not hear Saros (female singers), due to Kol Ishah! We can ask similarly about Barzilai ha'Gil'adi (Shmuel II, 19:36).
Refer to 2:8:5:1, 3.
Hagahos Maimoniyos (Hilchos Keri'as Shma 3:16): We are not concerned for a voice that he is used to.
Vilna Gaon (OC 75:3): Some Rishonim, including Talmidei R. Yonah, Hagahos Maimoniyos and Mordechai, forbid Kol Ishah only at the time of Keri'as Shma.
Chomas Anach - perhaps the Saros who sang for Shlomo were his wives 1 and Pilagshim.
Seridei Esh: One may hear men and women singing together 2 .
Avnei Yashfe 2 (OC 5): The Isur of Kol Ishah is mid'Rabanan. (Perhaps it had not yet been enacted.)
Michlol Yofi: The Saros sang for Shlomo's wives 3 .
Ritva (Kidushin 82a): If a great Chasid 4 knows that he rules over his Yetzer ha'Ra, and lust will not seize him, he may look at and speak with Ervah and even give Shalom to a married woman; not all Chachamim trust themselves, like is clear from the Gemara here. (Perhaps Kol Ishah is no worse than looking - PF.)
Melachim I, 11:3: He had "Nashim Saros Sheva Me'os u'Filagshim Shelosh Me'os."
Chasan Sofer (OC Taharas Yadayim 14) was unsure about this. Tzitz Eliezer (14:7) - this is a minority opinion; most reject it.
This answer does not help for Barzilai. He himself heard Saros! (PF)
This answer does not help for Barzilai. He was not a Chasid. (PF)
What are "Ta'anugos Bnei ha'Adam"?
Metzudas David: They are things that people enjoy.
What are "Shidah v'Shidos"?
Rashi (from Gitin 68a #1): They are beautiful chariots - covered wagons. Rashi - the Gemara mentions Sheidah Teivah u'Migdal.
Gitin 68a #2: They are male and female demons.
Rav Sadya Gaon: They are instruments of musical and song.
Ibn Ezra: They are "Ta'anugos Bnei ha'Adam", i.e. women. Also, it mentioned all worldly desires - building, planting, flocks, treasure, hearing sons - there was no mention of women! The best Perush of Shidah is from Shoded - plundered women taken captive via force. The captor chooses as he desires. Shidah is singular; Shidos is plural. This is like "Racham Rachamasayim l'Rosh Gever" (Shoftim 5:30) - Racham is one [woman,] who has a womb; Rachamasayim is two. Do not say only one; some grabbed two [women 1 ].
Metzudas David: One special chariot with all kinds of beauty, and many other chariots.
Granted, this explains Racham Rachamasayim. Why did Shlomo mention one or two women? He had 1,000! (PF)