2. speakers
  3. 125390-84368

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
8 responses Add your response
oleschool's avatar
oleschool
722 posts
 
Amp should be fine .But if you have a nice set of headphones it will take some mula' to get to that level imho 🙏
zachawry OP
7 posts
 
The Contour 1.1s suffered from me being a $%@#$%^ idiot and brushing the tweeter, impacting it.  :(

It sounds listenable, not that bad. But I've been lusting after some new gear anyway. Also, I've gone down the rabbit hole with headphones for the past couple years, and the sound I got out of my Contours even before impacting the dome is so far below what I get with my headphones. 

I know I would have to spend more than what the Confidence C1s cost to approach the sound I get out of my Ethers (headphones), but I'd like to close the gap. 

Thanks everyone for their input. 
erik_squires
16,056 posts
 
I think you'll be fine.  The biggest issue with small listening rooms is early reflections and higher room modes.

Try it, if the amplifier isn't adequate you'll know very quickly.  For testing reviewers have to pre-heat the amps at 1/3rd rated power and then do full power testing.  That's kind of torture, but it ensures the amps are compared fairly. The cost and heat saving approach of NAD, Carver and others to use amps that can only handle full power for short durations is very smart for music. The top transients only occur very briefly.  The point is, I wouldn't worry about that. Go entirely by your ears.

But don't fall into the "discerning" trap.  Some speakers have very low impedances deliberately so you can go "OH, wow, these speakers totally show how much better amp X is vs Y!!" Buy speakers that are like the girl next door, sweet and amiable with everyone. :)

Best,

Erik
stevecham
3,340 posts
 
Did you blow or burn the tweeters? The reason I ask is that, if you are serious about either of these two speakers, you always run the risk of repeating the same damage, regardless of power ratings and amp capability.  If you need to listen at 95 dB or above (permanent ear damage is a certainty), make absolutely sure that 1) the speakers are rated to play that loudly given the volume of your room and 2) that your amp won't be clipping at the output required to drive them to such levels.  Remember, dynamic peak requirements at any given moment at high levels can overburden the power supply of even a Krell, and, if the speaker receives even a momentary DC, it is likely to cause a coil burnout in one or both speakers.
tls49's avatar
tls49
1,351 posts
 
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?

bombaywalla's avatar
bombaywalla
1,958 posts
 
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. 
czarivey
5,946 posts
 
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.

rodman99999
6,130 posts
 
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.
Log in to respond
More to discover
80x80
Infinity Intermezzo 4.1t
80x80
Focal Diablo Utopia Colour EVO Focal Diablo Utopia Colour EVO
80x80
Von Gaylord Audio VG-8 MK II Speakers