www.neumann.com
Forums:
Email:









Re: Difference NS 69i and NS 69k?
Author: Uwe Sattler/NeumannUSA
Date: 03/25/2011
Before you sold the CU48, did you have the opportunity to make comparisons to the NS69/SM69fet performance? I hope you were able to confirm that there physically and technically can not be any difference at all. Just because some theories may sound plausible to some and are expressed with confidence, does not make them real!... However, as David has valiantly tried without stepping on anyone's toes, a basic understanding of electronics and the ability to read and correctly interpret the schematics of the devices involved are all that is necessary to debunk the false theories proposed by some 'experts'.
1. As David pointed out repeatedly, the path for the audio signal is identical and direct for either the NS69 or the CU48 with 48V phantom supply.
2. The advantage of alleged better headroom, dynamic range and 'current reserve' claimed for the NS69 VS CU48 quickly evaporates when examining the schematic diagram of the SM69fet, The 120v from the NS69 is reduced to 33V by Zener diodes and current limited by 180kOhm series resistors. Similarly, the 48V phantom power is reduced by the very same zener diodes through a 22kOhm series resistor (in series with another diode and the 2 parallel 6.8kOhm phantom recovery resistors. The stabilized 33V is then filtered by the R/C-combination of a 10 kOhm resistor and 10uF capacitor. Thus, regardless whether the microphone is powered by 48V phantom power or by the 120v from a NS69, internally any peak power reserve can only be satisfied from the 10 uF filter capacitor via a 10kOhm from the fixed Zener regulated 33V source.
3. With only neglibile current needed for the capsule bias circuit, there is no audible or measurable difference whatsoever between the NS69 and CU48.
I keep wondering what some golden ears claim to hear, but that no physical reality can explain or verify...  
 
Reply
Herman Grimme
05/02/2006
David Satz
05/02/2006
Herman Grimme
05/03/2006
David Satz
05/04/2006
Herman Grimme
05/04/2006
David Satz
05/04/2006
erik sikkema
05/04/2006
Herman Grimme
05/04/2006
erik sikkema
05/04/2006
Klaus Heyne
05/08/2006
Herman Grimme
05/10/2006
David Satz
05/10/2006
Herman Grimme
05/10/2006
Klaus Heyne
05/11/2006
G M Le Roy
03/24/2011
Herman Grimme
03/25/2011
Uwe Sattler/NeumannUSA
03/25/2011