INPUT/OUTPUT IMPEDANCE


Hello pro's,

I don't want to over think this, but I just pulled the trigger on a power amp rated at 10k(RCA) 15k(XLR) input impedance. Problem is I don't know the output impedance of my pre/pro(Marantz av7705). I looked everywhere and even called Marantz. My gut tells me all is ok...or is it!  I know you should be within the 1/10 ratio. So, does it make much difference whether your 1/10 or 1/100 ratio?

Thanks,
Anthony
antho768

Showing 2 responses by mapman

Ok but practically to keep tube preamp options open it’s much safer to go with an amp explicitly designed to handle that which spec wise means higher input impedance than 10kohm more like 60-100kohm typically with most products I have seen.
Bel Canto ref amps are a good example. Older models with stock Icepower modules only had 10k input impedance and users with tube preamps reported poor results. Newer models since cost more but added custom input section with 100kohm unbalanced input impedance. Those like the ref1000m amps I use with ARC tube pre-amp are a match made in heaven.
Either is likely fine from an input impedance perspective. 

Usually it is tube pre-amps that have higher output impedance that some SS amps can handle better than others typically with input impedance ~ 40 to 60 Kohm or higher. 

Anthem amps are products I have heard recently that I would consider owning. Have not heard Parasound but those are also highly regarded in general. Either should work well and sound good it seems in your case.

If you think you would ever consider using a tube preamp with the amp you choose I would choose the amp with the higher input impedance which sounds like the Parasound, all other things being equal.