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Passive preamps and poweramp's input impeadance

I have a Rotel poweramp with 33khoms input impeadance, and thinking about driving it with a Creek OBH-14, which is a passive preamp/DAC combination. I have been advised that the Rotel's input impeadance may be too low..
How would this affect the sound etc..., and would it be a bad idea? (I'm unable to test before buying). The Creek would also be driving a NHT SA-2 sub amp.. which I do not know the input impeadance for.
Your comments would be greatly appreciated.
arni
tom_nice
387 posts
 
Two comments: (1) I've successfully used a 10K ohm passive with a Pass Aleph power amp, input impedance 23K ohms, and Nelson Pass told me that others report the same success, (2) if you can rig up a simple resistor network, you could find out whether a passive will work with your Rotel amp. Details on request if you're interested. A little soldering would be required, and four RCA jacks, and two or three pairs of resistors.
hackmaster
102 posts
 
Well maybe Nelson pass says it's ok but I sure as hell wouldn't run a 10k ohm preamp into a 23k ohm amp. Just my two cents worth. Sure it'll work - but it's not going to sound as good as if the impedance were matched better.
unsound
7,315 posts
 
I think Symphony Sound is right. Working and optimizing are birds of a different feather. Arni, the Rotel's input impedance does make for a classic candidate for a passive pre. Not knowing the source specs or cableing prohibits a defintive answer. The fact that it will be driving a sub amp as well, doesn't bode well.
unsound
7,315 posts
 
Arni, please forgive me. I made a huge error in my previous post. It should have read as: "the Rotel's input impedance does *NOT* make for a classic candidate for a passive pre."
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