Tuesday, November 27, 2012

Nine Easy Steps To Fit A Turntable Cartridge

Fitting a cartridge to one’s turntable may seem to be a dying art in the hi-fi world, but does the nine easy steps shown proof that it doesn’t have to be?

By: Ringo Bones

Given that leading legal commercial digital music download sites have yet to make their music wares sound as good as the Redbook spec 16-Bit 44.1 KHz sampled CDs offered by Mobile Fidelity Sound Labs and other music outlets catering to audiophiles, it was the supposedly dead music format – in the form of the vinyl LP – that made the biggest revival in the second decade of the 21st Century. Most entry-level turntables are supplied with a cartridge already properly fitted in by the manufacturer as a complete package. But even if you happen to buy an upmarket turntable without a cartridge from a specialist hi-fi dealer, it’s very unlikely to leave the shop without one being properly fitted – especially if you’re a first time buyer or just a vinyl LP novice.

Fitting a cartridge these day and age can be considered a dying art, but careful installation is vital to ensure a good sound. Simply attaching one at random to the front of the tonearm is likely to do more harm than good, severely damaging your records; So one should follow the proper simple guide for perfect results every time. For the benefit of those who were not yet born – or were too young to remember - during the vinyl LPs heyday during the 1960s and 1970s, here’s nine easy steps to fit a vinyl LP cartridge to your newly acquired turntable.

1  )      Loosely fit the cartridge to the slotted grooves in the headshell of the tonearm. Tighten the mounting nuts and bolts, but leave enough slack to reposition the cartridge by hand.

2  )      Using a pair of tweezers - fit the four color-coded wires from the tonearm onto the appropriate color-coded pins at the rear of the cartridge.

3  )        Place the turntable on a level platform. Remove the stylus guard from the cartridge. By moving the rotating counterweight to be found at the rear of the arm, attempt to balance the cartridge, so that the arm floats freely along the horizontal plane. Set the free-spinning dial on the counterweight to zero and dial in the tracking force of the cartridge by moving the entire counterweight assembly. The tracking force is usually given in the cartridge manufacturer’s specifications and is typically between 1.5 grams and 2 grams.

4  )      Place an old record on the platter but do not set the platter spinning. Place the arm on the record. By sight, try to make the cartridge parallel to the record. Replace the arm on the rest and adjust the Vertical Tracking Angle of the cartridge by raising or lowering the pillar at the rear of the tonearm.

5  )      Adjust the overhang and tracking of the cartridge using an alignment protractor like the Polestar. Take great care to get the alignment correct, as care and attention at this point reaps great sonic rewards. Once this alignment is correct, tighten the cartridge bolts so that there is no more play and the cantilever is the only part of the cartridge that can still move. Re-check the alignment, in case it has been moved accidentally when tightening the mounting bolts.

6   )      Repeat steps 3 and 4 with greater care and attention.

7   )      Position the anti-skating dial (or adjust the hanging weight) to match the downforce of the cartridge being used.

8   )      Clear away all the tools, sit back, relax and play a record. The cartridge will normally take many hours to run in – if you are impatient, leave the cartridge tracking through a locked groove (like The Beatles’ Sergeant Pepper) for a weekend. This will help to bed the cartridge properly.

9  )      Remember that most moving magnet cartridge have a removable styli that should be replaced every two to three years, depending on use. Unfortunately, moving coil cartridges do not have removable styli and need replacing – or retipping – every two to three years or so.

Tuesday, November 20, 2012

The Microphone: High Fidelity Audio’s Final Frontier?

Though a topic more likely to be discussed and reviewed in a professional-audio magazine than in a hi-fi magazine does the microphone truly represent the final frontier in our pursuit of high fidelity sound?

By: Ringo Bones

During the Golden Age of Stereo, all audio recording equipment – even one’s destined for domestic use – were all equipped with microphone inputs to facilitate do-it-yourself recording for the audio enthusiast. And as time went on – as in around the 1980s, every audio recording gear destined for consumer/ domestic use – like hi-fi cassette tape decks and later recordable CD decks, mini disc, DCC and even DATs – seem to forego the inclusion of a microphone input as a feature. Given that virtually all music and audio recording that we will eventually be listening to our home audio gear was first captured by microphones, does the microphone truly represent the final frontier in our quest for high fidelity sound that’s indistinguishable from the one that occurs naturally? Or does existing microphone technology actually “hear” music the way our ears do?  

As stated by Stereophile magazine editor John Atkinson during the recording of their Encore CD in the January 1998 issue of their magazine, there is absolutely nothing natural about recording an acoustic event – let alone making it sound as natural as possible. As a testament as being the engineer of the scores of recordings commissioned and sold in Stereophile, Atkinson – and probably every other experienced recording engineer like him – is ready to admit that microphones don’t “hear” music in the same way that our ears do. And far from being natural, are actually chosen for their sound during sound recording / music recording.

As an example in the live Classical Music recording session world – if one is recording violins, the polar distribution of the radiated power along the axis of the violins’ top plates is such that it will overwhelm any other sounds the microphones are intended to record – so one is forced to record from any position but one along that axis. Most recording engineers choose to raise their microphones well above it since that solves other problems relating to the way microphones perceive – or “hear” - the musical instruments on a performing stage.

To cite Atkinson’s another example: Simply by using spaced omni-directional microphones, a recording engineer can create an illusion of spaciousness that may not truly exist in the recording venue. The distance between the microphones affects lateral time cues on the recording; the perception of spaciousness can be profoundly influenced simply by varying that spacing.

The rather novel microphone setup known for its unrivaled naturalness in capturing the sound of the recording venue used by John Atkinson on all of the Stereophile live music recordings made in the 1990s are compared to “multi-way speakers” by other recording engineers since the microphone setup is optimized to pickup either the lower or the upper part of the audible spectrum. They consist of two outrigger B&K omnis that were hung by their leads from the ceiling 8-feet from the stage and 13-feet from the floor. A central pair of B&K cardioid microphones was mounted on a stereo bar, and hung by their leads from the center of the ceiling 11-feet above the level of the stage and the same 8-feet back the omnis. The two cardioids were used in what is called an ORTF configuration: the mikes angled at 115-degrees, their tips spaced about 7-feet apart. The ORTF microphone technique was developed in France and gives a nicely defined soundstage, but the tonal balance lacks low-frequency bloom. The spaced omnis, on the other hand, give a wonderful sense of bloom and very accurate tonal color, but have mediocre stereo imaging. Such rather elaborate setup results in a Classical Music recording that has the sound-staging of a minimally-miked recording with a tonal naturalness of a multi-miked recording.

Unfortunately, such recording set-up that works very well in the Classical Music recording world doesn’t work very well in the heavy metal / rock world – which requires quite a different microphone, recording  and mixing set-up altogether. One of the problems is purely technical: To create a clean heavy metal / rock recording with excruciatingly loud electric guitars is extremely difficult when the guitar amps, the drum kit, and the vocalist via a loud PA system used as a monitor are all going at the same time in the same room / acoustically unisolated recording venue.

 Because the sound of the instruments leaks into the microphones used to record the sounds of the other instruments, a muddy sound is the result. Given that most bootleg heavy metal / rock concert recordings made from the 1970s and the 1980s have their sound captured by a microphone set up that resembles the one intended for minimally miked Classical Music recording, most bootleg heavy metal / rock recordings tend to be unbearably muddy sounding in comparison to their studio recorded counterparts – or a live concert recording “overseen” by a skillful FOH mixing engineer. In conclusion, we still need skillful live music recording engineers / FOH mixing engineers to make existing microphone technology sound as natural as the way our own two ears hear music – whether Classical or heavy metal rock.