In Rivendell, did Saruman try to use his "Voice" on Elrond, Galadriel and Gandalf?

Question

In The Hobbit: An Unexpected Journey (2012), when the company arrive to Rivendell, Gandalf is asked to attend a surprise reunion with Elrond, Galadriel and Saruman the White. Saruman then opposes himself to Gandalf's involvement with the Dwarves and his plan to get rid of Smaug. Gandalf then reveals his concerns about the Necromancer, but Saruman is skeptical, not believing the Necromancer to be a true threat and minimizes the danger.

Was this speech an attempt from him to utilize his power known as "The Voice of Saruman"?

Answer 1

Highly unlikely for two reasons :

1. Elrond, Galadriel and Gandalf were all far too powerful within themselves to fall under Saruman's spells.

2. Saruman didn't align with Sauron until a long time after The Hobbit's events took place and had no reason to convince them that the Necromancer was not Sauron.

Once he was as great as his fame made him. His knowledge was deep, his thought was subtle, and his hands marvelously skilled; and he had a power over the minds of others. The wise he could persuade, and the smaller folk he could daunt. That power he certainly still keeps. There are not many in Middle-earth that I should say were safe, if they were left alone to talk with him, even now when he has suffered a defeat. Gandalf, Elrond, Galadriel, perhaps, now his wickedness has been laid bare, but very few others.

Aragorn talking to Legolas and Gimli as they enter Orthanc with Gandalf, King Theoden and Eomer to speak with Saruman. Source

It's highly likely that Saruman was simply skeptical that a Necromancer existed, as he believed Sauron had been defeated forever:

Gandalf talks with the White Council (Elrond, Galadriel, and Saruman the White) about his involvement with the Dwarves, explaining the presence Radagast encountered and expresses mild suspicion that this necromancer is the Dark Lord. The others are skeptical, believing Sauron to have been defeated forever, and that this necromancer is not a true threat.
Source

Answer 2

It's plausible that Saruman was already evil during the events of The Hobbit. Treebeard's explanation of Saruman to Pippin and Merry is indeed curious (emphasis/bold mine):

[Wizards] appeared first after the Great Ships came over the Sea, but if they came with the Ships I never can tell. Saruman was reckoned great among them, I believe. He gave up wandering about and minding the affairs of Men and Elves, some time ago--you would call it a very long time ago . . . He was very quiet to begin with, but his fame began to grow. He was chosen to be the head of the White Council, they say; but that did not turn out too well. I wonder now if even then Saruman was not turning to evil ways . . . I used to talk to him. There was a time when he was always walking about my woods. He was polite in those days, always asking my leave (at least when he met me); and always eager to listen. I told him many things that he would have never have found out by himself; but he never repaid me in like kind. I cannot remember that he ever told me anything. And he got more and more like that; his face, as I remember it--I have not seen it for many a day--became like windows in a stone wall: windows with shutters inside. I think that I now understand what he is up to. He is plotting to become a Power.

Two things. Treebeard hasn't seen Saruman in a long time--which when Treebeard says a long time, HE MEANS IT! And, Saruman was already corrupt from Treebeard's description. So, it's plausible that he would want Sauron on the chessboard, so to speak, to create a situation where he could be the one who might "become a Power."

EDIT: I suppose what I mean is that Saruman vying for power could be spotted and stopped. The Necromancer, however, would be a diversion! And, it worked---Gandalf was caught off guard when he traveled to Saruman only to be imprisoned atop Orthanc.

Answer 3

At the time of The Hobbit Saruman had sent servants to search the Gladden Fields west of Mirkwood, so yes, he was already 'evil'. Beforehand he had already compelled the Council of the Wise not to assault Dol Guldor, fearing that it might indeed be Sauron and henceforth accelerated his search efforts of the Great River of Anduin up to the Gladden Fields for the One Ring.