The Lord's voice

There is a portion of the Bible where it talks about the Israelites hearing the voice of the Lord and being so frightened of it that they asked Moses to go talk to Him alone, rather than having God talk to them directly. 

Deuteronomy 5:22-25:

"...The Lord spake unto all your assembly in the mount out of the midst of the fire, of the cloud, and of the thick darkness, with a great voice: and he added no more. And he wrote them in two tables of stone, and delivered them unto me.
 

"And it came to pass, when ye heard the voice out of the midst of the darkness, (for the mountain did burn with fire,) that ye came near unto me, even all the heads of your tribes, and your elders;

"And ye said, Behold, the Lord our God hath shewed us his glory and his greatness, and we have heard his voice out of the midst of the fire: we have seen this day that God doth talk with man, and he liveth.

"Now therefore why should we die? for this great fire will consume us: if we hear the voice of the Lord our God any more, then we shall die."

I've always thought that the Lord's voice must have been booming and frightening at that time. But when I was reading about it yesterday, the incident is cross-referenced with the following verse:

"And it came to pass that while they were thus conversing one with another, they heard a voice as if it came out of heaven; and they cast their eyes round about, for they understood not the voice which they heard; and it was not a harsh voice, neither was it a loud voice; nevertheless, and notwithstanding it being a small voice it did pierce them that did hear to the center, insomuch that there was no part of their frame that it did not cause to quake; yea, it did pierce them to the very soul, and did cause their hearts to burn" (3 Nephi 11:3).

The Lord's voice is not loud or harsh, but it is so powerful that it does pierce, burn, and cause people to quake.