Meridian MCD & MCD Pro CD players Manufacturer's Comment
Editor: The review of the Meridian MCD by George M. Graves raises a number of questions. Bob Stuart unequivocally states that Meridian has never produced an MCD with tantalum capacitors in the output. The 68µF capacitor used is of the solid-aluminum type mentioned by Mr. Graves as being used by Philips in his Magnavox player. While aluminum capacitors look very similar to tantalum capacitors, they are most suitable for audio use.
Moreover, the aluminum caps in the MCD are bypassed with polypropylene and polystyrene units. High-value capacitors for AC coupling of audio circuits remain a problem in the design challenge facing any audio engineer. Even at less than one-third of the required value, the polypropylene caps used by Mr. Graves are, as he himself pointed out, physically too large to be used in the MCD.
We are happy that Mr. Graves found the MCD to be "far superior" to the FD1000. As to improving the MCD, Mr. Graves will no doubt be happy to hear that the new MCD Pro is DC-coupled, with no capacitors in the output. This, along with a number of improvements to the digital as well as the analog circuitry of the MCD, enables the MCD Pro to set a new standard for the quality of CD playback. The original MCD, somewhat improved over the units shipped to reviewers a year ago, remains available as a less-expensive alternative to the $1400 Pro version. The sound quality of the current MCD remains unsurpassed among commercially available players except by its professionally oriented younger brother.
For the benefit of your readers, I would like to offer a caution to those who may consider modifying commercial products they have bought, a caution that goes beyond beyond the loss of warranty any such tampering produces. Mr. Graves is apparently technically competent to experiment with electronic circuits for himself and evaluate the desirability of the results in his particular system. The value of capacitance used, however, could result in significant variation at the low-end response of the MCD into some preamplifiers. Modifications that seemed to help in some ways in particular circumstances may very well not produce the same results in other environments. The average consumer would be unwise to presume that the original designer of his equipment was unaware of the possibility of the suggested modification. As often as not, the alleged improvements have been considered by the original designer and rejected due to a tradeoff of performance in other respects. As in everything, caveat emptor.—J. Michael Wesley, Madrigal
There continues to be disagreement between George M. Graves, who is an electrical engineer and who deals with electronic parts on a daily basis for Fujitsu, and Madrigal on the nature of the capacitor used in at least Mr. Graves' example of the Meridian MCD. Since Madrigal made the above point, GMG went back to the MCD to examine it; he continues to think that it uses tantalum capacitors.
It doesn't really matter too much: the important point was that the unit sounded much better when polypropylene capacitors were substituted. It is gratifying that no capacitors at all are used in the output of the MCD Pro, an example of which is here in Santa Fe and will be reported on quickly.
Mr Gates agrees with the next-to-last paragraph in Mr. Wesley's letter; the modifier must judge for himself the success of his modifications—not all results will be good, and no warranties will be valid!—Larry Archibald