ROYER Labs Model SF Stereo Ribbon Velocity Microphone Operation Instructions Manual & User Guide Made in U S A
TA BLE OF C ONTEN TS Model SF Stereo Ribbon Velocity Microphone Table of Contents page 1 Introduction page 2 Description page 2 Users Guide page 2 Amplification Considerations page 3 Recording Techniques: -Conventional X-Y Recording page 6 -Mid-Side (M-S) Recording page 7 Applications page 9 Care and Maintenance page 11 A Little Bit of History page 12 Features page 13 Specifications page 13 Wiring Diagram page 14 Frequency Response and Polar Pattern page 14 Warranty page 15
Introduction Congratulations on your purchase of a Royer Labs model SF-12 ribbon microphone. The SF-12 is a handcrafted precision instrument capable of delivering superior sound quality and overall high performance. This operator’s manual describes the SF-12, its function and method of use. It also describes the care and maintenance required to ensure proper operation and long service life.
intelligently. 1. The SF-12 is a side-address, bi-directional microphone and the rejection in the “dead” areas is very strong. Due to this directionality, ribbon microphones should be placed at 1.3 times the distance normally used with omni-directional microphones, or about the same distance used for cardioid microphones. This method is used to achieve the same ratio of direct to reflected sound. 2.
“dynamic” microphones will relate to moving coil dynamics. All condenser microphones have a built in preamplifier called a head amp and therefore put out a hefty signal. Because the signal is buffered through the head amp, the output impedance is rather low and less affected by the input impedance of the microphone preamp.
stereo or multi channeled microphones, such as the SF-12. Ground loops can develop in the preamplifier with any stereo microphone, regardless of the type (i.e. condenser, dynamic, ribbon). A ground loop manifests itself as unwanted noise, buzz or hum (usually 120 Hz). The condition is brought on when the left and right transducer elements are plugged into two inputs of a stereo or multi-channel preamplifier.
Hum Noise and Mic Orientation All dynamic microphones, including ribbons, utilize powerful magnets in their motor assemblies and matching transformers, and are, to some degree, susceptible to picking up stray alternating magnetic fields. Power transformers (such as those found in guitar amplifiers) and alternating current motors are the most likely sources of radiated noise. Building wiring and electrical utility transformers are other likely sources.
sound curtain with sources outside this included angle appearing to be outside of loudspeaker placement. Figure 1 shows the alignment of polar patterns when the microphone is oriented this way. Because of the “togetherness” of the transducers, sound will arrive at both microphone elements at the same time. This means that the two channels can be summed to mono with no comb filter effects, and room reverberation (undesirable in mono) is cancelled to a surprising degree.
front of it as before. Now the S microphone will respond to the source, but the M microphone will not. If the sound source moves to the left of the microphone, again the S microphone will respond but the M unit will be silent. The important fact to note is that the output of the S microphone will be 180 degrees out of phase to what it was when the source was at the right. Please keep this in mind, because it’s crucial. Examine the block diagram of Figure 4a.
for reasons already stated. Now we move the sound source to the “left”. The signal falls off somewhat as heard by the M microphone, but picks up at the S microphone. Because of the electrical phase of this signal, it adds to the M signal feeding the “left” channel, making the sound appear to be coming from the left. Signal also feeds the “right” channel, but out of phase with respect to the M signal that also feeds the “right” channel.
produced by switches and adjustments. Its small size and matte black chrome finish create a minimum disturbance of the visual field, especially important where the microphone must not obstruct the view of an audience or of a motion picture or TV camera. The SF-12 is easy to use, robust and reliable. Neither temperature nor humidity affects it. SF-12 has numerous applications.
This microphone does not suffer from overload because there are no integral electronics. Therefore, the available dynamic range is determined solely by the characteristics of the preamplifier with which it is used. In summary, the SF-12 is truly a microphone for all seasons and is a refreshing change from the philosophy of “dedicated” mics geared to specific instruments or voices. Care and Maintenance The SF-12 is a well-built precision instrument.
CAU TION! Keep recorded tapes spring wound watches and personal credit cards using magnetic coding away from the microphone to prevent possible damage caused by the transducer’s magnets A L i t t le Bi t o f H i st o r y The ribbon-velocity microphone design first gained popularity in the early 1930s and remained the industry standard for many years. Their characteristic sound signature can still be appreciated today in recordings of the 30s, 40s, 50s and early 60s.
Features • • • • • • Wide, Smooth Frequency Range Closely Matched Characteristics Negligible Off-Axis Coloration Excellent Separation and Imaging True Figure-8 Polar Patterns X-Y or M-S Recording Specifications Acoustic Operating Principle:Electrodynamic pressure gradient Polar Pattern: Symmetrical Figure-8 Generating Element: 1.8 micron aluminum ribbon Frequency Response: 30Hz - 15000Hz ±3dB Sensitivity: > -52dBv Re.
W i r i n g D i ag ram Polar Pattern Frequency Response 14
Warranty Royer Labs warrants its products to be free from defects in materials or imperfect workmanship. This warranty is offered to the original owner without time limit. Royer Labs will repair or replace any product that fails to meet published specifications during the warranty period. This warranty does not apply if the product has been damaged by accident or misuse, or as a result of repair or modification by other than a Royer Labs customer service facility authorized to service this product.
