Nagaoka MP-500 Cartridge Lab Report

Lab Report

Last tested over a decade ago [HFN Feb '11], Nagaoka's 'Moving Permalloy' pick-up has remained very consistent in production. By current standards, its output into a standard 47kohm load remains a 'middling' 3.1mV (the Ortofon 2M series MMs will achieve up to 7mV/1kHz re. 5cm/sec) but the channel balance is rather better than Nagaoka's conservative 1dB rating at just 0.3dB. I would still not recommend loading the MP-500 with a parallel capacitance of >100pF, however, as the cartridge's native response already shows a gently declining treble that falls 9dB from 10kHz to 20kHz following a 1-2dB boost through the presence region [see Graph 1, below]. Also, its compliance is rather higher than the rated 8.5x10-6cm/dyn at ~30cu suggesting the MP-500 is best suited to life in low-to-medium effective mass tonearms. VTA, too, is higher than anticipated at 30° so the latter, and the top-end response dip, might well be ameliorated by raising the tonearm slightly at the rear.

Otherwise there's much to commend this proven Moving-Permalloy mechanism. Tracking is excellent, even at a low 1.7g test downforce (a wide 1.3-1.8g range is specified) as the MP-500 sails through the top 80µm groove pitch and navigates the max. +18dB groove (re. 315Hz/5cm/sec) at <0.8% THD. The excellent symmetry of the MP generator is also a worthy 'feature', illustrated not only in the matching lateral/vertical response trends [Graph 1] but also in the uncommonly low lateral/vertical and stereo distortion vs. frequency [see Graph 2]. Very few pick-ups, of any type, achieve a sub-3% stereo THD from 20Hz-20kHz (–8dB re. 5cm/sec) and a peak of <7% , in this instance at 14kHz, with discrete lateral/vertical cuts. PM

223cart.lab1

Freq. resp. curves (–8dB re. 5cm/sec) lateral (L+R, black) vs. vertical (L–R, red) vs. stereo (dashed)

223cart.lab2

Lateral (L+R, black), vertical (L–R, red), stereo (dashed) tracing and generator distortion (2nd-4th harms) vs. freq. from 20Hz-20kHz (–8dB re. 5cm/sec)

Generator type/weight Moving-Permalloy / 7.8g
Recommended tracking force 13-18mN (17mN)
Sensitivity/balance (re. 5cm/sec) 3.11mV / 0.3dB
Compliance (vertical/lateral) 28cu / 30cu
Vertical tracking angle 30 degrees
L/R Tracking ability >80μm / >80μm
L/R Distortion (–8dB, 20Hz-20kHz) 1.6-4.8% / 0.7-2.8%
L/R Frequency resp. (20Hz-20kHz) +1.2 to –10.8dB / +1.1 to –8.5dB
Stereo separation (1kHz / 20kHz) 26dB / 14dB
Price £799 (£899 in headshell)

COMPANY INFO
Nagaoka Trading Ltd
Shibuya-ku, Tokyo, Japan
Supplied by: Sound Design Distribution Ltd, Cardiff
0800 0096213
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