amp or preamp to extend upper end

Evolving: in my experience the preamp has more influence on the upper frequencies than does the amplifier. At least when you get to a certain level of performance. I don't have any experience with Musical Fidelity components so I can't talk about their sonic signature. But yes, going from a Krell to just about anything, you better not rely on anything but your own ears, because Krells do have the reputation of NOT being soft or rolled off in the top end. Good luck.

06-02-15: Zd542
Try turning the high frequency contour adjustment on your 3's up 1db.

+1 (meaning that I agree with ZD's suggestion, as opposed to suggesting that another db be added to the 1 db he suggested :-)). I took a look at John Atkinson's review of the Vandersteen 3 in the March 1993 issue of Stereophile. He states:

Although I found that the tone-control settings that gave the flattest measured response were HF -2dB, and MF, + 1dB, this sounded consistently too dull. I ended up setting the HF control either at 0dB or +1dB for most of my listening.

He also mentioned that the woofer and mid-range needed to be worked hard over the course of a very extended break-in period before they sounded good. If by any chance your speakers weren't used a great deal around the time of the transition between amplifiers, perhaps some re-breakin is necessary, possibly contributed to by age-related stiffening of the surrounds, or some other comparable effect. Keep in mind that the crossover between mid-range and tweeter, nominally at 5 kHz, is first-order, meaning that the mid-range driver will be receiving frequencies at significant amplitudes well into the top octave.

Regarding the other subject that has been addressed in the thread, FWIW my perception in recent years is that in initial quality surveys and long-term user satisfaction surveys, while most of the big-name German manufacturers seem to place not much better than the middle of the pack among all manufacturers, Porsche is just about always at or very close to the top, even though recent models are loaded with all kinds of high-tech electronics and other such things. Also FWIW, my 2014 Cayman S has been all that my wife and I had hoped for when we purchased it about a year and a half ago, although for many people its two seats, very limited cargo capacity, and stock high performance tires that can't be driven on snow or ice would rule it out as a practical choice. And no doubt any repairs that may be necessary after its 4 year warranty expires will not be cheap.

Regards,
-- Al

ZD, I detected failed transmission solenoid $60 part(car
would not engage reverse gear). the customer already signed
repair order to replace transmission. Now figure out how
much money you can spend on BMW repairs factually. You can
spend thousands of $ for $60 part. Well, I do not.

In my experience, I have found that a pre and the amp each work best if they come from the same manufacturer. Sometimes if they aren't you can end up with surprises. The same manufacturer designs these things to work together..

06-06-15: Stringreen
In my experience, I have found that a pre and the amp each work best if they come from the same manufacturer. Sometimes if they aren't you can end up with surprises. The same manufacturer designs these things to work together..

From my experience, I find as long as the pre (low impedance) can drive the amp properly, it's a good match. They don't need to come from same manufacturer.