(((I will say I’m a bit surprised about RV’s questioning of a manufacturer’s specified input impedance not being as stated, )))
It’s not about trust or questioning or what the input impedance spec in the owners manual reads.Its what the voltmeter reads plain and simple.
The reason this is misunderstood is some amps have
J fet drivers some bipolars which measure slightly different at 1000 vs100 hz or 80 hz
((The absolute only way is to confirm is with an AC Volt meter not an owners manual))
Install red and black voltmeter probes in amp speaker binding posts turn down volume in pre amp play Vandertones CD track 27 1000 hz with Voltmeter set to AC millivolts adjust pre-amp volume slowly up till it reads 1V AC then play track 30 for 100 hz Vandy five, seven, Quatros, etc or track 31 for 80 hz Vandy 2W 2WQ or new Sub 3 if your xover dip switches are set properly or installed at amp factory it should read .707 If not start from the begining adjust dip switches untill you have it set properly.I also think you are fine with the Rogue Pharaoh if you confirm above or your amp was done at Rogue and measured as above.
Best,JohnnyR,Vandersteen Dealer
It’s not about trust or questioning or what the input impedance spec in the owners manual reads.Its what the voltmeter reads plain and simple.
The reason this is misunderstood is some amps have
J fet drivers some bipolars which measure slightly different at 1000 vs100 hz or 80 hz
((The absolute only way is to confirm is with an AC Volt meter not an owners manual))
Install red and black voltmeter probes in amp speaker binding posts turn down volume in pre amp play Vandertones CD track 27 1000 hz with Voltmeter set to AC millivolts adjust pre-amp volume slowly up till it reads 1V AC then play track 30 for 100 hz Vandy five, seven, Quatros, etc or track 31 for 80 hz Vandy 2W 2WQ or new Sub 3 if your xover dip switches are set properly or installed at amp factory it should read .707 If not start from the begining adjust dip switches untill you have it set properly.I also think you are fine with the Rogue Pharaoh if you confirm above or your amp was done at Rogue and measured as above.
Best,JohnnyR,Vandersteen Dealer