No, the rules specifically state that you cannot do this.
However, the description of "Sight" range does not include such a clause. Make of that what you will 
Does anyone else understand how these statements are not mutually contradictory?
Meanwhile...
I want to recant my previous position - Sight magics can increase a range. This range is based on what the caster can "see" - so scrying spells increase this range.
Voice works diff, tho'. As the rules state, it's based on "the distance that the voice carries", and "magical enhancements", etc. I understand this combination to mean "naturally".
That's why I have quotes around use magic. You can't affect the Range : Voice with magic. You can "go up a level" and use Range : Sight, or Range : Arcane Connection and define it in game as "Magically enhanced Voice", because you want the extra range, but like the silenced or quieted limitation that comes with Range : Voice. It gets tricky if you want to, say, make a spell that has an Range : Arcane Connection, that "screams", deafening everyone in Range : Voice of the Arcane Connection. The canon (on page 112, under Arcane Connection) is unclear. It seems to imply that some spells have two ranges.....
It is not magically enhanced voice. it is another ranging method. Range resitrictions and advantages do not apply.
Cheers,
Xavi
The complete quote should have been : "You can "use magic" to increase voice range. You just have to go up the range table to do it." Which I at least understand to mean take that extra magnitude and go to sight range 
You CAN NOT increase VOICE range with magic. EXPLICITLY stated in the rulebook. So you can NOT have a voice range spell with incrweased range.
If you want more range you use SIGHT range, tha tis a totally different range from voice range: it is not magically enhanced, but a different thing.
I am starting to think that people see letters, but not words in this thread 
There are few rules sentences where the wording is so clear as with magical enhancement of voice range
Xavi
Xavi is right, unless you kiss the rules good-bye, which is something I would be very hesitant about, because most of the rules are there for a reason.
...film at 11:00... 
You can use MuVi to boost range, so you can use magic to increase range of voice range spells to sight of arcane if you are a pro.
Don't make me write an essay on the word "boost". 
Boosting the range (from voice to sight) is not the same as boosting the range of the voice.
Well, if you stick with what is writed rather than go with the spirit... 
Thank you ExarKun. Ars Magica is a very dynamic game, with many paths to get the effect you want. If a mage has a voice theme, taking the hit on magnitude (Range : boundary, (all those who can hear my voice)) shouldn't be a problem.
But I notice that no one seems to be discussing what I thing is the interesting thing, the line in Range : Arcane Connection (Page 112). "Some spells require that the caster have an Arcane Connection, but the spell must be cast as some range other then Arcane Connection.". It seems to imply "range stacking". Like a spell with Range : Arcane Connection, Range : Circle, say, to view anything in a circle you have an Arcane Connection to...
Your voice is not a well defined boundary. That would not fly at all IMS. A well defined boundary is a glade, the borders of an island or the wall of a city. Not "the range of your voice" or "the area where there are squirrels". Targets and ranges are well defined for a reason. otherwise the sistem can be playable (oh yes) but we are back to 2nd edition of the game with a game that is not consistent internally. Like DnD, basically. You can dop that, but is not the RAW at all.
What ExarKun mentions is explicitly AGAINST the rules. If you go for a "boost" in voice range and move to Sight you suddenly are NOT using the virtues and flaws of the Voice range, but those of the Sight range. You are not boosting: you are using a different parameter. They are extremely different so you are moving in a completely different league. If I add yellow to blue I get green, not a "boosted blue". The effect of the color is different than with adding a lighter blue to the mix that would still mean that I am using a blue color. In your example you added yellow and got green. The effects can be extremely cool and interesting, but they are not blue anymore so considering them to be blue is just plain wrong.
You can cast a sight spell without speaking. You can cast a sight spell while blind. You cannot do the opposite in those 2 cases. Different ranges, different resitrictions and advantages.
And yes, you stack those.
Xavi
MuVi , wizard's reach is against the rules?
Good to know. 
ExarKun who don't argue for pennies.
Exactly, ExarKun. Wizard' Reach clearly states that it can increase the range of the affected spell. Range : Voice becomes Range : Sight. But the spell should "stay the same" thematically. We all understand that out of game, the spell is now Range : Sight. But in game, your voice should be ringing through the hills.....
BUt there is the vital difference precisely 
You are NOT looking at a voice spell with a longer reach for your voice. You are looking at a spell with Sight range. For one thing you could cast it at sight range without speaking, since it no longer has the range problem of a voice spell. it is a redesign of how the spell works here. You are not talking louder. The restrictions and advantages of each range parameter are different, and do not carry over between categories. The ring spell restrictions and advantages do not hold if you boost it to group. The same happens with the reach parameter. The change is way more fundamental than what you are describing. It is not the reach of your voice that is boosted, but the reach of the spell. Different targets and effects.
Cheers,
Xavi
Exactly
Well, EK, I am unfortunately not a medium or a shaman. I don’t communicate with spirits. I only communicate through words, written or spoken. So in order for there to be productive communication, we must make reference to what is written. What is “spirit” to one person is “shenanigans” to another. I cannot read your mind and thus cannot discern your intent in any way other than reading what you write and referencing it against RAW (and the “W” stands for “Written”, not “Wraith” or any other sort of “Spirit” that starts with a W).
No, no, no. That is rules weaseling to a shameful degree. A “sound” is not a “boundary”. You need Bjornaer Sensory Magic to do that, specifying a Target of “Sound” (which is still not a Boundary).
Xavi is dead spot on correct. In ArM2 and one, there was no Parameter to define Target. It was simply based on what felt right, leading to a very high degree of inconsistency between troupes (and even printed supplaments!).
Quoting people out of context an attaching false interpretations to their words works on the news, but not on a forum where I can simply scroll up and read the original post.
What Xavi really said was…
And the analogy that follows is spot on as well.
No, no, no. The spell is now been changed to a Sight range spell. No voice is needed at all. Your voice does not go “ringing through the hills”. That is well and fine for thematic color for your game, but that is a HR and not RAW.
More of Xavier’s wisdom…
Exactly. The effects of the spell remain the same, but the Range and the rules for operating at said range are now totally different. I mean, seriously folks! By analogy, EK & Sax, would you suggest that if I Boost a Touch range spell to Voice, that suddenly I have become like Mister Fantastic or Plastic Man, and that my arm stretches out 50 yards so I can “Touch” someone at “Voice” range? I think not!
Two things, Marko. I am not claiming Sound as a Boundary. I am saying that a player who wrote a spell with Range : Boundary shouldn't have a problem with "Self-limiting" the spell as "All those who can here my Voice", if it's thematically appropriate. As, indeed, the game suggests may be needed sometime. See Wizard's Tower. Still requires a Boundary, but with the limitation that you or the area can be silenced. I don't see the problem. This is not power gaming, this is, if anything, unpower gaming.
As to Wizards Reach, the subject of that spell has not been changed, it has been "boosted". Thematically, it should look different then the spell with the "higher power" built in. Maybe not Elasticman, but perhaps an image of your hand goes racing to your target.
As a long time storyguide, I find "unpower" gaming much more annoying than "power" gaming.
Boosting a parameter (R/T/D) is in fact changing it. No amount of semantics can cover that up, not if we are to be speaking in the same language (and if I sound snippy, I apologize and hope you take no offense, I am just that way and you can still be a broseph). The MuVi guidelines specifically use the word "Change". Any sort of alteration is a Change, be it a Boost, a "shrink", or any difference at all from the original.
Mystic Tower does not require a Boundary. It is T: Individual. And you cannot Boost a spell to Boundary anyway. Boundary always requires a Ritual, and unless the spell was a Ritual to begin with, the Boundary Parameter is not an option.
Bonus points for mentioning Elasticman! I forgot about him, and Elongated Lad.
But you understand my point, and are using semantics to dance around it. This "thematic" approach works for you, and by all means continue using it in your game! But it is not the Rules As Written, it is your own personal interpretation, and thus you are not on the same common ground as most players. There is no "phantasmal hand" involved when boosting from Touch to Voice. You have made a "Significant Change" in the spell (reference MuVi, ArM5 pages 159 & 160). It is no longer a Touch spell, it is now a Voice spell. What was an apple is now an orange. The are both round and they are both fruits, but they are still different.
A Touch Range spell requires you to physically touch the Target/subject. You do not have to make any sounds if you are willing to accept the -10 penalty for No Voice (or if you have the appropriate Virtue or Mastery).
Boosted to Voice, it is now a Voice Range spell. If don’t use words, then there is no spell, even if you have the appropriate Virtue or Mastery. Though you can still cast a soundless Voice spell on yourself, it would be pointless to have boosted the Range to Voice to do so.
Boosting from Voice to Sight, you no longer have to use words (accepting the penalty or using a virtue/mastery), but you cannot cast with your eyes closed (as you were able to with a Voice spell).