Newby Q about impedances etc.


Hi,

I'm a longstanding audiophile-wannabe, but I have very little actual knowledge. 

The system I've used for a long time is a Krell KAV 300i into Dynaudio Contour 1.1s. 
The Krell is fed through a Chord Hugo into a Microzotl2, a tube headphone amp that also doubles as a pre-amp. (Most of my recent listening has been on headphones)

Anyway, the Dynaudios are damaged and I want to replace them. 

I like the sound signature, and I have a small listening space, so I'm considering the Confidence C1s, which have the following impedance profile: 
Sensitivity 85 dB (2,83 V/1 m)
IEC Power Handling 170 W
Impedance 4 Ohms

Or, the KEF Reference 1:
Amplifier requirements 50-200W
Sensitivity (2.83V/ 1m) 85dB
Impedance 8Ω (min. 3.2Ω)

The Krell is kind of old, but it delivers 150W/ch into 8 ohms or 300W into 4 ohms.

Is the Krell powerful enough to power the Dynaudios? It seems like it should be, but I want to make sure. I found reviewers saying that it shouldn't go full-power into 4 ohms for extended period. Of course, my listening isn't going to be at full power, but I want to have headroom as well. 

Finally, I'm going to be auditioning these speakers, but I expect them to sound different in the store than they will at home. Anyone have any experience or comparisons between the two? 

Thanks a lot. 


zachawry
The specs of your Contours and other mentioned choices are so close as to be inconsequential.     If you're not changing rooms and expect to listen at the same SPLs as before, you shouldn't have any problems.
Totem Forrest will meet all of your expectations and will become your Krell's best mates. Your Krell is powerful enough to drive C1 and speakers you've mentioned. It's in fact one of the best Krell designs.

I beg to differ a bit....

the Confidence C1 are spec'd at 85dB/2.83V/1m, 4 Ohms.

so. really that's 2W into the speaker once you do the math. To normalize that to another 8 Ohm speaker, we will have to half the input power (down to 1W). This means that the sensitivity will drop 3dB.
So, the Confidence C1 are actually 82dB/1W/1m, 4 Ohms.
You can use this number as a direct comparison to the KEF Ref 1 (which is spec'd correctly since it's an 8 ohms speaker).

You have a 3dB difference in sensitivity bwtn these speakers. It might all work out just fine for you but Keep that in mind when you decide. 
Looks like the Contour 1.1 is also spec'd at 85db/2.83v/1m, 4 ohms, so 82db at 1 watt. With this low sensitivity I'm curious as to what is the damage to them and did it happen while playing? How do they sound currently?