Can I make the same comment that higher impedance is receptive to noise, in the same context that lower impedance adds distortion. Seems like most of the Class-D amps Stereophile measured included power ratings at 2ohms. It just thought it was weird they didn't include those measurements for the M700 amps. |
Can I make the same comment that higher impedance is receptive to noise, in the same context that lower impedance adds distortion.Probably not. The impedance of a 16 ohm loudspeaker will not affect noise floor at all. But many 16 ohm loudspeakers are also fairly efficient, and if there is noise efficiency means that you will hear it. |
thosb wrote:"..hopefully you have checked out the Thiel users group thread, lots of good discussion on amp pairing, lots of good discussion on how to get the most out of the CS5s, more focus on what listeners are hearing rather than technical debates..." Thank you for the reality check. There is a lot of good technical advice here from a variety of folks who responded on this thread. The problem, of course, is how much a non-tech type can absorb. For example, I still do not understand phase angle and its implications (among other topics). I guess I was hoping for a magic bullet to my original post but that, of course, is unfair to everyone. I am not sure the pocket book can deal with a switch to a more efficient speaker and all the opportunities/changes that might require; so I probably will wade through all 6800 plus responses on the Thiel Owners thread again...I am retired so that should not take too long...😊 Thanks for listening, Dsper |
dsperThese are the facts Dsper. you have a great speaker that demands in turn a great Linear amplifer to get the very best sound out them, not one that has compromises. 1:Stereophile bench tests the CS5 "Means that the amplifier with which it is used MUST HAVE ample TO SAY THE LEAST current capability, if the sound is not to become anemic. Amplifiers with limited current delivery to become starved in the low bass <2ohms, with a potentially disastrous effect on dynamics." 2: I have yet to see a Class-D measured by Stereophile to do what good linear amps can into loads <2ohms and that is to "almost" double wattage for each halving of impedance, 8 to 4 to 2ohms. 3: Stereophile I also do not think have ever shown a Class-D full power wattage into 2ohms without it freaking out or switching off, this proves they are not comfortable into 2ohms like linear amps can be. Cheers George |
Class D amps will have problems with 2 ohm loads especially if your in a condo or apartment building, since the switching transistors constantly modulate the current from the a.c. outlet and the available current can vary which time of day other tenants are using the most electricity. The solution? Stay away from class D amps that don't have large extra power supply boards that will handle low ohms when your current is low. For the money, the costly Nuprime Evolution One at $8K a pair has a massive bank of capacitors and will laugh at 2 ohm loads. No problem. Or their lower priced mono blocs, the ST-10M at $3200 a pair. It is always best to buy a Class D amp with a large power supply found in A/B amps. The Nuprimes are killer due to the fact their switching amps are custom designed in house protected by their own patents and former top design engineer at Spectral, Damien Martin, has been an ongoing consultant for the company. The Nuprimes are sleeping giants. |
