cartiage for Kenwood L07D genuine tone arm

08-09-15: Jagdzaku
If I used a higher compliance cartridges, for example, Van del Hul Frog ( 35 Micron/mN ); what's wrong with it?

Compliance is how flexible the cartridge's suspension is. The higher compliance, the more readily it "wiggles," which should correspond to the effective mass of the tonearm. The higher the compliance, the less the tonearm's effective mass should be; the lower the compliance, the heavier the tonearm's effective mass should be.

The combination of tonarm effective mass and cartridge compliance always creates a resonant frequency. This resonance should be between 8 and 12 Hz, ideally 10 Hz. A lower resonant frequency can cause "woofer pumping" and rob the music of a good bass. It can also make the tonearm more prone to jumping the groove. A resonant frequency above 12 Hz starts to interfere with audible bass.

Here is a cartridge/arm calculator. For effective mass, you combine the effective mass of the tonearm plus the weight on the cartridge. In the case of your 17g Kenwood arm plus 8.2g Frog, that's an effective mass of 25.2g. Compliance is 35. Enter those numbers, click "Calculate" and you get a resonant frequency of 5.359Hz, which is way low.

Use the second calculator to find an ideal compliance for ideal resonant frequency: For example, if you have a 6g cart mounted to the Kenwood tonearm, you have 23g effective mass. For an ideal 10Hz resonant frequency, you'd want a compliance just above 11. Altogether, the "safe" 8-12 Hz range allows compatible compliance from 7.648 (@12Hz resonance) to 17.2 @8Hz resonance.

Jagdzaku, I wouldn't let the stock tonearm discourage purchase of an LO7D. It is a superb TT, even without the arm. If you have access to a machinist, it is feasible to devise a generic turntable mount that will clamp down into the stock tonearm pod collet and accept pretty much any surface mounted tonearm(e.g. Dynavector, Trans-Fi, Talea, Kuzma, Schroeder.) I've had great results with Trans-Fi on L07D.

Jonnyb53,thanks for input. I have to admitted I did not considered it before
in some vintage preamp, there is a low frequency cut ( <20hz)；does it work?
Dgarretson，I will consider it on the second arm! :)

Jagdzaku,

Even if your phono preamp has a LF filter, an arm/cartridge combo with a native resonance of ~5-6Hz is asking for trouble. At a minimum, it would impair clean tracking and overexercise the suspension in the cartridge, possibly shortening its life.

Anyway, most LF filters do not operate as brickwall filters (unlike the HF filter in redbook CD players). SOME of that LF energy is going to make its way past the filter and into the amplification chain. At best, that adds sonic mud and raises your system sound floor. At worst, it may overstress amps or speakers.

Listen to Johnnyb53, he answered well.

Any and all low frequency "rumble filters" that I've tried robbed the musical presentation of a solid foundation and much of the life of the music.

Those LF filters were mostly for attenuating the "rumble" or motor noise of idler-driven turntables, and not for taming bad arm/cartridge mismatches, which can affect things (such as tracking) long before the result would reach the speakers.