HVAC duct sizing or CFM's causing air noise?

Hello all,

I have installed a split system air conditioner (air handler with
outside condensing unit) for cooling my recording studio built onto my
home.  The studio is 2 rooms.  One room is 20' by 14', and the other
is 20' by 10'.  My friend calculated the heat gain and losses and came
up with needing a 1.5 ton unit, so that is what I purchased.

The specs on this unit says it (the air handler) delivers
approximately 975 CFM's on the low fan speed.  My ductwork consists of
2 12" flex returns (1 in each room), 4 6" flex duct supplys in the
larger room, and 2 8" supplys in the smaller room.

PROBLEM:  I seem to have way too much air flow (yes, probably air
volume) coming from the vents.  This is also causing a lot of air
noise, as well.
You can feel LOTS of air from the vents, even at 4-6' from them.

SOLUTIONS???  I have thought of doing the following in this order, but
need some practical suggestions...

1)  Install damper on supply end of air handler.

2)  Reduce fan blower's speed/CFM's

3)  Increase duct sizes to all registers.


I believe a problem was introduced when my friend did the duct sizing
based on a 1.5 ton air handler.  When I went to order the air handler,
they asked if I wanted 10 SEER or 12 SEER.  I naturally chose the 12
SEER.  What this meant is the air handler is really a 2.5 ton air
handler, which has twice the CFM's of the 1.5 ton model!

Any help is appreciated!!!

(Please don't bash me or my HVAC skills.  I am a DIYer, but I'm not
totally ignorant on the sublect.  Plus, I enjoy the challenge here!)

Thanks,
Junior
[EMAIL PROTECTED]