Ortofon today and tomorrow 

The best way to sustain the Ortofon heritage is to develop new products and introduce new technology.

Ortofon measurement technique, Part 1

We would like to hereby present the Ortofon approach on how the tests of cartridges are being performed along the production process. We would shed light on the following areas of the test system:

• The measurement chain and the records used
• The quality of the test system

The measurement test chain 

The Ortofon measurement test set-up is a PC based test system. Prior to testing, the cartridge is mounted on a special headshell, that has been optimized for repeatable and reproducible use. The cartridge is connected to an amplifier, which is adjusted for an input impedance of either 100ohm, 200ohm or 47kohm/220pF (cable capacitance incl.) depending on two elements:

1. The impedance characteristics of the cartridge
2. The type of the cartridge, i.e. Moving Magnet or Moving Coil

Then the signal is amplified with a gain of +40dB for MM and +60dB for the MC types.The amplifier has a switch for measurements with/without RIAA-equalization. For low frequencies below 1kHz the test is being performed with the RIAA equalization curve set to ON/automatic switch. For high frequency tests the switch is set to OFF allowing maximum bandwidth since the records have been cut linear and non-equalized.

Subsequently the signal is converted through an AD-converter and filtered for optimal use of the PC capacity. The data is finally stored on a hard disk.

For each MM/MC model a set of limits, reflecting the performance of the cartridges, is being used.

After the system has been hooked up, a calibration sequence is initiated and the data stored. The sequence compensate for changes in temperature, humidity etc. The calibration sequence also compensates all cables, impedances, gain etc in the measurement chain from the headshell to the PC.

Three sequences of the test

1. Testing sensitivity, channel separation and balance: we are using track 1 and 2 on DUAL PVK 321. The measurements are performed at 1kHz with a speed of 5cm/s. The AD-sampling is at 40 kHz, an average of 1000 measured data is used. The filter is a Bessel IIR Band Pass of 6th order with cutoff frequencies of 50Hz and 10kHz.
2. Testing tracking: we are using track 4 on DIN 45549. Detection of tracking is performed at 315Hz. It is chosen to register on the 4th, 5th and 6th harmonics in an FFT signal analysis. The filter is similar to what is applied in the first test sequence.
3. Testing frequency response: we are using Technical Record Series from JVC -1005 track 1-6. For this test the sampling is performed at 250 kHz, an average of 3000 measured data figures is used. The filter is a Bessel IIR Band Pass of 3rd order with cut off frequencies of 500Hz and 80kHz.

After testing, the product is approved by the quality control if the product performance data meet the given test specifications. All Ortofon cartridges are subject  to quality control and test.

Measuring chain

The steps in the measuring chain are subsequently:

1. Cartridge mounted in test headshell and/or tonearm 
2. Amplifier with RIAA switch
3. AD converter
4. BandPass filter: 6th order Bessel (IIR)
5. PC (Results for QC)
6. Store data on HDD

Test equipment (subject to changes):

Test records used:

Calibration equipment (subject to changes):

Ortofon-Serato S-120 DJ cartridge 

Ortofon is proud to announce the release of a revolutionary new high performance cartridge for DJs, co-developed with Serato Audio Research.

The new Ortofon-Serato S-120 DJ Cartridge has a patent pending design using a unique suspension system. This patent pending technology can probably be used in future HiFi products.

All vinyl DJs will benefit from the extreme tracking ability delivered by a revolutionary new cantilever suspension. With 4.0 gms of vertical tracking force, the Ortofon-Serato  S-120 achieves an amazing tracking ability of 120 μm compared to the conventional 80 μm at 315Hz. That is a 50% improvement on standard DJ cartridge performance.

Mr. SPU Robert Gudmandsen   

Robert Gudmandsen, known by most as Mr. SPU, is the father and founder of Ortofon large pickup program, which is still the world's largest by a single manufacturer.

Robert Gudmandsen began to work with Ortofon on December 6th, 1941 and remained in the company for more than 50 years. On the occasion of his 50-year anniversary with Ortofon, Robert Gudmandsen was awarded Her Majesty Queen Margrethe II meritorious medal.

Robert Gudmandsen started his career as a radio engineer in a company where his father also worked, and from there he was brought to Ortofon by Arnold Poulsen, one of Ortofon's founders. Initially, Robert Gudmandsen worked on production of a dynamic amplifier for a local radio station.  Later he was also involved in the production and development of condenser microphones.

In 1945-46 Ortofon started production of cutting heads for the mastering of new LP records. This led to development and introduction in 1948 of the first SPU - Stereo Pick-Up, which was the first Moving Coil pickup in the world. This first stereo pickup actually consisted of two parallel-mounted pick-ups. The armature was connected to a common cantilever via an extremely complicated universal joint with sapphire bearings. (Universal joint design is no longer applied for production of Moving Coil pickups). SPU also has a new elliptical needle, which gives somewhat lower wear at approx. 4-g needle pressure.

Along production of MC cartridges, Ortofon also developed Moving Magnet pickups.
These were initially somewhat clumsy and with a very low output. Robert Gudmandsen was involved in developing of Variable Magnetic Shunt principle that solved many problems; among other things obtained a high output and very low moving mass.  A contributing factor to the success of VMS pickups was a specially developed rubber suspension, which together with the low mass secured a very large frequency range.

The VMS pickups, although well received, were replaced with new technology in the 80s, whereby even higher output of the MM pickup was obtained.

For many years Robert Gudmandsen brought the pickups home to try them. It was something that both neighbors as other local residents enjoyed. Today Robert Gudmandsen has many other hobbies outside of audio. When he does choose to enjoy music, he prefers opera, for example Prisoner chorus from Verdi’s Nabucco and also the Norwegian soprano Sissel Kirkeboe.

Today Ortofon has the world's largest program of pickups in all price ranges and all types, but despite the development of the new pickups from Ortofon, Robert Gudmandsen, as well as a legion of music aficionados, prefer the sound of the good old SPU. Robert Gudmandsen enjoys his retirement in the small town of Præstø, located between Copenhagen and Ortofon's headquarters in Nakskov.

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• Measurement technique, part 2
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• Individual cables
• New product range