Cube Audio Nenuphar Single Driver Speaker (10 inch) TQWT Enclosure

Stephen,
Congratulations!
It’s interesting that this simple step reduces the DF by a factor of 10 and improves what was already a very high level of sound quality. This was an excellent suggestion from the knowledgeable Vinnie Rossi. It certainly does stimulate the curiosity of what happens if DF is reduced to 8. Fun stuff.

Cal,
Since an amplifier’s DF and output impedance have an inverse relationship I wonder if this output impedance is ’effectively’ increased with use of the resistors or is the nominal speaker impedance as seen by the amplifier decreased?
Charles

Speaking of DF, a couple of weeks ago I was cruising the intranets reading about damping factors and came across an article by a couple of guys who put together PA systems (which explains why they talk about speaker cable lengths of 50 and 100 feet).

At any rate, they noted that the DF decreases with longer speaker cables so I may try 8' versus 16' speaker runs. They provided some numbers:

50'    12AWG   8ohm   DF= 49.1
50'    12           4                  24.5
50'    12           2                  12.3
100'  12           8                  24.9
100'  12           4                  12.2
100'  14           4                    7.9
100'  16           4                    4.9

@charles1dad I know some Avantgarde Duo XD owners uses SIT-3. The Avantgarde’s nominal impedance is 18Ohm which is way too high for the SIT-3. Hence many uses another 12Ohm register (off-coarse based on Pass recommendation) in parallel for the amp to see a lower load impedance just under 8Ohms. Its interesting that adding a register in series lowers the damping factor but this will also increase the nominal impedance. I am now curious if this technique could be applied with the SIT-3 and Nenuphars to further reduce the damping factor. I guess the only way to find out is to write to Pass :-)

Hi debjit_g,
DF=Speaker impedance (In ohms) ÷amplifier output impedance. 
So to lower the DF either the amp output impedance must increase (Denominator) or the nominal speaker impedance is decreased (Numerator). Unless there's something I'm missing. With amplifier specifications the lower the output impedance the higher the amp's DF. This usually reflects the amount of NFB employed in the circuit. 
Charles 

Obviously a positive outcome regardless of the reason, but this discussion just makes me more confused. In the numbers posted above, doubling load resistance doubles dampening factor while VR indicates that adding 1 ohm to the load cuts damping but a factor of 10??

Does anyone know what might differentiate between a resistor changing output impedance vs changing amplifier load?  As I see it, this alters how much resistance is in the post-amplification circuit. Good that it worked, but color me confused.