Thanks, Wayne.
I am looking at a Protek 506,
(http://www.protektest.com/ProdInfo.asp?prodId=506)
with 'DB Readings' and 'RS-232 interface & software'.
Do you think the spec. ranges: -31.6 to + 59.71dB, is enough for 90+ dB speakers? I sent an email and I got no answer from them. Also I will use the computer as I sine wave generator.
Regards