[A6] A6 sine osc

[MelloT at aol.com]

In a message dated 3/13/2005 5:42:47 P.M. Pacific Standard Time,  
cwd10 at psu.edu writes:

>>>The biggest problem with A6 is that the mixing is too  powerful for the 
buffers which causes distortion at even medium levels, let  alone high levels.>>>
That's not a problem, as much as it is the ONLY synth that has  intelligently 
been designed for this mixer situation. When the A6 was first  built, they 
COULD have made the mixer as such: if all oscillators and sub's are  set to 
100%, they do not distort the mixer. This how many old synths work. The  A6 does 
not do this. Why?
 
It has two problems: 
1) One single oscillator set at 100% is only pushing the  mixer to less than 
25% of what it is capable of; this is bad  for signal-to-noise and bad for 
sound quality.
2) Those who want to distort the mixer for more harmonic  content cannot ever 
do it. (This was a trick on old Minimoogs - raise the gain  into the mixer so 
that audible distortion results and thickens the sound.)
 
The Alesis people decided to allow the current setup - even one  oscillator 
at 100% can drive the mixer hard. But if you have  more than one, you ought to 
reduce the input levels by a corresponding amount.  Two oscillators should be 
50% or less apiece, and even lower if the sub's are  being added. Intelligent 
use - by listening - is the key....
 
However - this Alesis choice can result in what people find - they hit the  
mixer too hard, causing a less-than-ideal tone. It's the opposite of what many  
people are trained (lower levels = sound quality). On the A6 lower  levels 
can mean more punch and clarity, only because the gain allows  for a lot in the 
mixer stage. 
 
Having looked at a lot of waveforms of old synths on o'scopes over the  
years, you'd be surprised at how "off" some are. But they still make music and  
still work. It's no surprise to synth techs that many instruments do not give  
off pure sine or square waves.

 
BrianK