[RTTY] Checking Sound Card performance on RTTY with Audio Analyzer

[RLVZ at aol.com]

Hi Guys,
 
Thank You for your recent comments regarding 75 Baud RTTY.  I  think I'm 
ready to "go at it" this weekend.
 
I am trying to check out the performance of my computers sound card  
running RTTY with MMTTY and using a K3 for the receiver and Spectran audio  
analyzer software.  Here are the numbers I'm getting:
 
1) Cable to sound card input disconnected, noise floor  averages -100dB.
 
2) Cable connected from K3 rcvr to sound card input but no signal,  noise 
floor averages -70dB.
 
3) Same as #2 above but with an S-9 signal, signal averages -44dB  or 26dB 
above the no signal noise floor.  
 
QUESTIONS: 
 
a) Is 26dB a reasonable S/N ratio for a  built-in mother board sound card?
 
b) How much could I likely improve the S/N ratio with a better  quality 
sound card?
 
Thanks & 73,
 
Dick- K9OM