A couple of issues back, we mentioned in passing that the Fidelity Research FR-1 Mk.3F was the only moving-coil cartridge we had heard (as of then) that we would give house room to. (The others had frequency-response problems which so colored the sound that their other strong points were not worth the tradeoff.) That first observation about the FR-1 was based on a couple of hours’ listening. Now that we have had an opportunity to live with one of them for a while, we can essentially confirm that first reaction, but with a few added qualifications.
This is in fact one of the few MCs that doesn’t suffer from a brightness suckout and a high-end sizzle. In fact, it sounds rather like a Shure V15-IV elliptical in tonal balance, even to the point of sharing that cartridge’s slight hardness. (The spherical G version of the Shure sounds more neutral.) But there the resemblance ends.
The F-R has a fairly high degree of internal damping, which holds the low-end resonance in an un-damped arm to around 6dB. (Arm damping reduces this further.) Compliance is moderately high—closer to 15cu at 12Hz than the 10 figure cited in the specs—which rather narrows the field when it comes to compatible arms. Even with the SME 3009 III, which is one of the lowest-mass arms available, the cartridge’s 10-gram weight places the arm/cartridge resonance at around 10Hz, which is close to ideal (12Hz is better). With most other arms, including Fidelity Research’s rather massive ones, the resonance drops to below 8Hz—into the range where the system is responding excessively to some record warps. The resulting subsonic interference can be filtered out, but the filtering sacrifices some low-end tautness, and cannot restore the imaging accuracy that gets messed up by the excessive stylus flexing.
We are also a little dubious about the FR-1 Mk.3F’s required 2-gram tracking force. This is nothing to worry about with a spherical-tipped cartridge, but with a biradial stylus, even a line-contact one such as this, contact pressure at 2 grams will be high enough to cause some groove wear with repeated playings. (With a spherical, disc and stylus wear virtually cease at tracking forces of below 1½ grams—assuming, that is, that the cartridge can track cleanly below that force.)
Because of its high compliance, the FRl-Mk3F is one of the few MC cartridges whose low-frequency tracking ability rivals that of the Shure. Unlike most MCs, it sails through those ridiculous’ cannon blasts on Telarc’s 1812 with nary a trace of distress. But, even with the SME tonearm’s highly effective damping system, we were forced to agree with some other reviewers who reported that the cartridge’s low end seemed a little lacking in impact. We could not ascertain a reason for this, and thus report it only as an unsupportable observation.
Measurements
The F at the end of this cartridge’s model number is supposed to stand for Flat. Neither of our two samples was. Our response measurements (fig.1), made with the CBS STR-100, STR-130, and B&K 2010 test records were in fact in sharp contradiction to the “calibration” curves supplied with the cartridges. They sounded more like our curves than like F-R’s. What more can we say?
Fig.1 Fidelity Research FR-1 Mk.3F, Frequency response (top) and crosstalk (bottom) (10dB/large vertical div.).