Amp/Preamp Asylum

Posted by rfarris (A) on July 19, 2008 at 14:59:50

This is a review of the Musical Fidelity kw500 and kw550 integrated amps for those interested in these integrateds. Apologies to those who might feel this is dated or covers well trodden ground.

First, the disclaimer. I like MuFi products. I own and greatly enjoy a Nuvista M3 and, to cut to the chase, I bought the kw500. As I write I am sitting here being blown away by it.

Today’s comparison was on a pair of PMC EB1i speakers with an Esoteric CD/SACD player. I don’t know what cabling the dealer was using.

The 500 struck me immediately with control. Control was my wife’s first impression as well. Increase the volume as you will and all that changes is, well, the volume. This amp gives extreme clarity and separation of musicians and notes in space. Space is abundant. The soundstage is deep and broad. Add volume and all of that stays utterly unchanged as does tempo. The 500 is highly transparent and tonally extremely neutral. Its trite, but true to say that my wife and I were surprised to discover things we had never heard before on CDs we thought we knew very well. The 500’s control produces highly tactile music. Bass is tight and taught. Guitar strings have pluck and punch. Piano keys have attack. I was just almost blown off the sofa by the kettle drum intro of Robert Plant’s “Some Like It Hot” my wife just threw on. The end result is fantastic level of realism.

The kw550 is a different animal. Its presents more punch and drive in bass and percussion that makes it more forward. At first listen it is seems more exciting and seems to give a bit faster pace. However, this comes with a loss of clarity and transparency. All that bass weight and warmth covers up a touch of detail in the mid-range and treble. Although we sensed this almost immediately, the magnitude of coloration is far from being a fatal flaw. It took several rounds of A/B comparison to convince ourselves we were right about this. And the visceral punch of the 550 is awfully attractive. I can see some people preferring the 550 over the 500. Ultimately we preferred what we felt was the accuracy of the 500 over the 550.

MuFi vs. Naim. We first heard the PMC EB1i speakers through a Naim 500, its matching pre-amp, and a Naim CD550. They offered very little competition to the MuFi kw500/Esoteric combination. The Naim amps seemed noisier, less transparent and detailed, and certainly lacked the sheer control and tactile power of the MuFi amps. I don’t know if it was the amps or the CD player, but the Naim system sounded a bit shrill whereas the MuFi/Esoteric combo offered purity. This applied to the kw550 vs. the Naim even if the kw550 sounds colored relative to the kw500.

Finally, the kw500 vs. the Nuvista M3. The 500 just does everything better. More punch, clarity, transparency, and control through the frequency range. The result is a jump in realism. All that said, I have been pleasantly surprised that the M3 is hardly an embarrassment next to the kw500. It is simply a slightly less powerful version. I feel the kw550 is a more colored amp than the M3. I had planned to sell my M3, but I increasingly think its moving from the sound room to duty in another room in the house.