Ortofon OM20

Type: Moving Iron (MI)
Stylus: Nude Elliptical
Compliance: High
Price: £160-175

HIGHLY RECOMMENDED

Background

Not far into my renewed interest in vinyl, I became aware that the Ortofon OM20 was well regarded amongst audiophiles. Browsing eBay one day, I noticed NOS examples of the Ortofon TM20 for sale at a knock-down price and bought one – this is a ‘p-mount’ cartridge that sports the same stylus as the OM20. I also bought an OM5E, one of the cheapest cartridges in the OM range, in order to obtain an OM body for my ‘Stylus 20’. I first tried the OM5E which was not without its merits, but its slightly coarse sound left me in no doubt that I was listening to a cheap cartridge. However, fitting the Stylus 20 to achieve an OM20 resulted in a transformation – a fuller, smoother and generally more refined sound. I have used the OM20 on several turntables but now deploy it on my Technics SL1200 Mk5. Note that this is mainly a review of the OM20 with the standard OM body rather than the ‘Super OM’ body, although the Super OM20 is also mentioned.

Equipment

Turntable: Technics SL1200 Mk5
Phono Pre-amp: Musical Fidelity M1 ViNL (with 200pF capacitance)
Amplifier: Yamaha A-S501
Speakers: Q Acoustics 3050

Sound Quality

The OM20 is a mid-priced cartridge with a nude elliptical stylus and therefore ought to offer some refinement over budget models, and this is certainly the case over its much cheaper sibling, the OM5E (which sports a bonded elliptical stylus of slightly lower compliance).

Treble: The treble is crisp, precise and nicely detailed, not being too forward but giving the sound a sense of air. There is certainly a refinement to the treble as compared with cheaper cartridges, such as the OM5E, and it strikes a good balance between sparkle and delicacy. 

Midrange: The mid-band is open and full-bodied, with a fair level of detail, giving a natural feel to vocals. The midrange is not particularly forward but has good presence. The handling of sibilant vocals on poor pressings is not amongst the best but is acceptable.   

Bass: The delivery of low frequencies is impressive. The bass is deep and assertive, providing a solid foundation for the sound. All the positive descriptions of bass that you can think of probably apply here. This is one of the best Hi-Fi cartridges I know for bass.

The overall sound can be described as solid and clean, thanks to the well-defined bass and treble. The balance is fairly neutral, perhaps a touch on the warm side of neutral. Dynamics are nicely delivered and timings are pretty tight, yielding a highly entertaining sound with good separation of instruments and an excellent sense of control. There is a nice flow to the sound and a smoothness that is achieved without being dull or overly warm. The result is a very pleasing performance that is easy on the ear and unlikely to induce listening fatigue.

The OM20 is sold in some territories in the form of the Super OM20 which employs the enhanced ‘Super OM’ body that was introduced for the more expensive OM cartridges (10, 20, 30 and 40). The Super OM body takes the same stylus as the standard OM body but renders a brighter sound. For me, the treble of the Super OM20 is too forward and the magical balance of the OM20 is lost. The Super OM20 could prove tiring to some people, although it may well suit a dull system.

Tracking

The tracking-force range for this cartridge is 1.25-1.75g with a normal value of 1.5g, which is the setting I use. Its tracking ability is obviously extremely good, as evidenced by the clean, precise sound. It falls apart a little on sibilant passages, but is far from the worst in this respect.

Compliance

This cartridge has a dynamic compliance of 25 cu (at 10Hz). As such, it is a high-compliance cartridge designed for low-mass arms. While I currently use it on my Technics SL1200, with an effective arm-mass of 12g at the low end of medium-mass, I have used it to very nice effect on strictly medium-mass arms, such as that of the Pioneer PL12D. I therefore wouldn’t hesitate to choose this cartridge for a low-mass or medium-mass arm.

Capacitive Load

The recommended range of capacitive loads for this cartridge is wide, being 200-600pF. I use a setting of 200pF on my phono pre-amp, which puts the total load capacitance (including 125pF cable capacitance) at ~325pF. This is consistent with using one of the many 200 or 220pF phono pre-amps available on the market. The cartridge would also perform well with one of the lower-capacitance phono pre-amps that have an internal capacitance of around 100-150pF.

Note that the above assumes a phono-cable capacitance of 125pF for the Technics SL1200 Mk5. This value may be higher (likely) or lower for other turntables. Typically, a value in the range 150-200pF is assumed.

Comparison

As already mentioned, the OM20 offers a definite improvement over its cheaper siblings in the Ortofon OM range, such as the OM5E and OM10 (although the latter is a respectable cartridge). I believe that it represents the sweet-spot of the OM range, as the differences that the OM30 brings do not justify the significant price jump. In the £100-200 price range, it is difficult to identify a cartridge that I could recommend more highly than the OM20, as I believe that it produces a sound that few people would not appreciate. If the skilful tracking of highly sibilant pressings is a priority then an Audio Technica cartridge with a MicroLine stylus may be preferable, but its sonic characteristics may not be as satisfying as those of the OM20.

Availability

The Ortofon OM20 is no longer promoted by Ortofon on their website – they prefer to push the 2M Blue instead, which would be the equivalent (with nude elliptical stylus) in the current 2M range. The OM20 cartridge is not generally available in the UK, although it is in some territories (such as Germany) in the form of the Super OM20 with an ‘enhanced’ cartridge body. I prefer the standard OM20, which is actually fairly easy to obtain.

The ‘Stylus 20’ is readily available in the UK and elsewhere, as are the cheaper OM cartridges (1S, 5S, 5E). Some vendors even sell the OM body alone (without a stylus) and a used OM cartridge can also be easily procured via eBay. Thus, an OM20 can be assembled from the body of one of these OM cartridges and the Stylus 20, bought separately.

It is also worth noting that many modern turntables (particularly from the Pro-ject brand) come fitted with an OM5E or OM10 as the stock cartridge. It is then a simple and effective upgrade to replace the stylus with a Stylus 20 to achieve an OM20 (and set the tracking force to 1.5g).

Conclusion

The Ortofon OM20 is a very pleasing cartridge which performs impressively well in virtually every respect. Its main characteristics are a solid, well-etched sound across the frequency spectrum, with a marginally warm tone built on a deep, punchy bass. As a relatively accomplished tracker, it has a remarkably clean delivery. Although high-compliance, it works well with medium-mass as well as low-mass tonearms. In my view, it is a notable improvement over sub-£100 cartridges, while more expensive £200+ cartridges won’t necessarily bring a significantly better or more entertaining sound. I consider the (standard) OM20 to be a pretty safe recommendation, as it’s difficult to see what is not to like about it.

If you need help with any of the turntable and phono-cartridge terminology used in this review, please visit the Terminology & Concepts page.