Warm Audio WA-47jr User Manual

WA-47jr

FET CONDENSER MICROPHONE

• ENGLISH (PG 1) • FRANÇAIS (PG 11) • ESPAÑOL (PG 16) • DEUTSCH (PG 21)

THANK YOU!

Thank you for purchasing the Warm Audio WA-47jr FET condenser microphone. We feel this product
offers the best in terms of sound, function, and vibe from the classic era of analog recording. We
don’t cut corners when it comes to what goes into our products, and the WA-47jr FET is no exception.
The WA-47jr FET proudly utilizes a custom reproduction of the vintage k47 capsule that was used in
the classic ‘47 microphone. The Warm Audio WA-47-B-80v capsule is designed with the same hole
pattern and frequency response as the vintage capsule and is carefully manufactured by an Australian
capsule supplier custom for Warm Audio. The capsule’s precise engineering allows the WA-47jr FET
to be able to obtain a very similar sound to the classic ‘47 microphone but at a much lower price tag.
The Warm Audio WA-47-B-80v capsule is also used in our flagship WA-47 tube condenser microphone
which is a companion to the WA-47jr FET.

We believe the WA-47jr FET represents an unprecedented value and will provide a lifetime of quality
recordings. We are honored to have the WA-47jr FET join your mic locker.

Bryce Young

President

Warm Audio

Liberty Hill, Texas USA

Register your WA-47jr FET!

Before we begin, please take the time to visit www.warmaudio.com to register your product. To ensure
you receive proper and uninterrupted warranty support for your product, please register your unit
within 14 days from purchase.

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WARRANTY STATEMENT

Warm Audio warranties this product to be free from defect in materials and workmanship for two
years from the date of purchase, for the original purchaser to whom this equipment is registered. This
warranty is non-transferrable.

This warranty is void in the event of damage incurred from unauthorized service to this unit, or from
electrical or mechanical modification to this unit. This warranty does not cover damage resulting
from abuse, accidental damage, misuse, improper electrical conditions such as mis-wiring, incorrect
voltage or frequency, unstable power, disconnection from earth ground (for products requiring a 3
pin, grounded power cable), or from exposure to hostile environmental conditions such as moisture,
humidity, smoke, fire, sand or other debris, and extreme temperatures.

Warm Audio will, at its sole discretion, repair or replace this product in a timely manner. This limited
warranty extends only to products determined to be defective and does not cover incidental costs such
as equipment rental, loss of revenue, etc. Please visit us at www.warmaudio.com for more information
on your warranty, or to request warranty service.

This warranty applies to products sold in the United States of America. For warranty
information in any other country, please refer to your local Warm Audio distributor. This
warranty provides specific legal rights, which may vary from state to state. Depending on the
state in which you live, you may have rights in addition to those covered in this statement.
Please refer to your state laws or see your local Warm Audio retailer for more information.

NON-WARRANTY SERVICE

If you have a defective unit that is outside of our warranty period or conditions; we are still
here for you and can get your unit working again for a modest service fee. Please visit us at
www.warmaudio.com to contact us about setting up a repair or for more information.

With the proper care, your Warm Audio gear should last a lifetime and provide a lifetime of enjoyment.
We believe the best advertisement we can have is a properly working unit being put to great use. Let’s
work together to make it happen.

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NOW LET’S GET STARTED!

INTRODUCTION

The WA-47jr FET offers one of the most coveted classic microphone capsule designs in an affordable
microphone circuit. The WA-47jr FET uses a high quality discrete transformerless circuit with Toshiba
FET’s, Wima film capacitors and Panasonic electrolytic capacitors. The WA-47jr FET brings the tone
and character of the classic ‘47 style microphone to you through the most critical component (its cap­sule) and is able to maintain an aggressive price-point by simplifying the rest of the circuit topology.
The WA-47jr FET’s simplified circuit is in no way a low quality circuit but is simpler to build and uses
less components than a vintage tube microphone, which allows us to offer it at such a bargain price.

The WA-47jr FET uses the same capsule as our flag-ship WA-47 tube microphone and sounds wildly
similar to the WA-47.

FEATURES

1. Pattern Select Switch

This switch selects the polar pattern for the WA-47jr FET’s capsule. The three polar pattern options are:
Omnidirectional, Cardioid, and Figure-Of-Eight.

2. XLR Output

The WA-47jr FET’s output is a balanced, gold-contact 3-pin XLR which accepts a standard XLR to XLR
shielded microphone cable.

3. High Pass Filter Switch

This switch engages a 70hz high pass filter for reducing rumble and other subsonic information.

4. -10dB Pad Switch

This switch engages a -10dB pad within the active circuitry.

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TECHNICAL SPECS

Cardioid at 1kHz

Omni at 1kHz

Figure - 8 at 1kHz

• Modern transformerless version of the highly coveted classic ‘47 microphone

• Custom made Warm Audio k47 style 34mm capsule (model# WA-47-B-80v)

• Capsule make: gold sputtered, dual large diaphragm, single backplate, 6 microns mylar

• Fully discrete signal path, Toshiba FET’s, Wima film capacitors, Panasonic electrolytic capacitors

• Polar Patterns: Cardioid, figure of eight, and omnidirectional

• High-pass filter: 70Hz

• Pad: -10db

• Self-noise: 9dBA

• Dynamic range: 138dBA

• Maximum SPL: 147/157dB (@1kHz 1kOhms 0.5% THD, 0/-10dB)

• Frequency Range: 20 Hz~20 kHz

• Sensitivity: 10mV/Pa or -40dB

• Output Impedance: 100 ohms

• Rated Load Impedance: ≥1kOhms

• Maximum output: 16dBu @1kHz, 1kOhms, 0.5% THD

• S/N Ratio: 85dBA (IEC651)

• Equivalent Noise: 9dBA (IEC651)

• Dynamic Range: 138dBA (IEC651)

• 48v phantom powered

• 3-Pin Gold-Plated XLR

• Weight: 1.1 lbs

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TIPS AND INSTRUCTIONS

MICROPHONES: IN THEORY AND PRACTICE

In this chapter, we will go over some general descriptions and advice on how to use your
WA-47jr microphone. We will begin with what the WA-47jr is and is not, and then briefly
discuss different applications and ways to get the best results from your WA-47jr.

The WA-47jr is primarily a studio condenser, which is to say it is a microphone that requires +48v
phantom power and a balanced XLR to XLR microphone cable, and a preamp with a 3 pin XLR
microphone input.

The WA-47jr is capable of delivering three polar patterns: cardioid, omnidirectional, and figure of
eight. We will go into the benefits of each pattern in greater detail shortly. The WA-47jr is considered
a side-address microphone in the sense that it’s capsule is mounted upright, projecting outward from
either side of the microphone when the microphone is stood upright or suspended upside down. The
front face of the microphone body is the side which bears the Warm Audio (WA) badge, and this is
considered the ‘front side’ of the capsule, with the opposite side of the microphone being the ‘back
side’.

GENERAL USES IN CARDIOID MODE

The classic ‘47-style microphone is known first and foremost as a lead and backing v
ocal microphone. It has been used to capture powerful vocal performances in rock, country,
hip-hop, gospel, blues, metal, voiceover/spoken word, and just about every other genre out
there. Two ‘47-style microphones for drum overhead recording, either in an X-Y configuration,
or as a spaced pair, is a classic choice. Likewise, a pair of ‘47-style microphones in an
X-Y configuration is a great way to achieve a big acoustic guitar sound. A single ‘47-style
microphone is a good choice for capturing many guitar amps, either alone or in
conjunction with additional dynamic or ribbon microphones. Since the pioneering days of
Joe Meek, ‘close mic’ing’ a sound source has become the norm in most genres outside of
classical music. This has made near cardioid pattern-only recording a fairly common practice. The
downside to this technique is an exaggerated proximity effect and lack of perceived space to an
instrument, the advantage is much greater isolation and control of individual instruments in a
mix. Close cardioid mic’ing’ also tends to capture less reflections and other unwanted information.

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TIPS AND INSTRUCTIONS

USES IN FIGURE-OF-EIGHT MODE

Figure of eight pattern recording is often used with pairs of the same microphone for advanced
recording techniques such as the Blumlein Pair array; but has several more common practical
applications as well, some of which only require a single microphone. One figure-of-eight application is
to record a ‘duet’ or group vocal with a single microphone. Two or even four vocalists can stand on either
side of the microphone, each getting the full attention of one side of the mic capsule. A variant of the duet
application is when someone plays an instrument, such as acoustic guitar, into one side of the
microphone while a partner sings into the other side.

USES IN OMNIDIRECTIONAL MODE

Omnidirectional pattern is most often associated with room mic recording, be it a room mic on a
drum kit or an ambience mic placed farther out from a guitar or bass cabinet, or other instrument.
Omnidirectional stereo recording is also sometimes associated with ‘live’ recording techniques and
classical recording. Additionally, an omnidirectional mic can be one ingredient, along with a figure-of-eight
microphone, in creating a Mid/Side stereo recording array. It is also worth noting that most
condenser microphone capsules are, by nature, designed to be omnidirectional devices. For this reason,
omnidirectional patterns tends to yield the most linear frequency response and suffer the least from
proximity effect.

MICROPHONE PLACEMENT & SPACING

When it comes to distancing a microphone from its sound source, one may think of this process,
among other things, as choosing a desired ratio of original sound source to reflections and acoustic
space. The closer to the source, the less space and ambience will be captured. In some cases, this
is fully desirable; and ambience will be added in later via the magic of digital delay and reverb. In
other cases, natural acoustics are critical. A great illustration of this is the recording of a gunshot or
cannon fire: at very close range, the sound is surprisingly thin; however, at a distance, the sound
becomes more full and explosive. This is a great reference to keep in mind; because to some degree,
this phenomenon holds true with anything where natural acoustics is an important part of the sound,
most notably with percussion. Beware that all processes do have boundaries and microphones do have
a maximum SPL level they can be subjected to without distortion. Both microphones and preamps have
a signal to noise ratio that tends to get poor in cases where more gain is required to make up for a
distant signal. It’s generally good advice to place a microphone about 12 inches from a source, and to
fine-tune it from there until you have exactly what you are looking for.

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TIPS AND INSTRUCTIONS

A BRIEF WORD ON ROOM TREATMENT

Room acoustics can be just as important as the microphone you choose. Even the best
microphone won’t sound great if you are picking up unwanted reflections that can smear or comb-filter
the sound you are recording. Just because a microphone is set to cardioid pattern will not always
mean that it is not picking up unwanted room reflections or outside noises such as street traffic,
footsteps, or air condition vents. Though a walk-in vocal booth is hardly necessary for most situations;
a good quality ‘vocal shield’ type of product can make an enormous difference, often making the
difference between a demo quality and a professional quality recording. Likewise, when recording
combo amps and other instruments, using gobos or other acoustic isolation products can be hugely
beneficial. Getting proper isolation and just the right amount but not too much room ambience
is one thing that really cannot be effectively corrected later in the process. It is of the utmost importance
to put in the extra time to set things up well in the beginning.

SIGNAL INTEGRITY

In professional audio a chain is only as strong as its weakest link. When it comes to microphone cable, a
quality cable can make a difference. Though not as critical as with instruments or dynamic microphones,
a thin, poor quality, or worn XLR cable can affect the sound of a microphone. With extreme age or wear,
gaps can form in the foil or spiral shield of a microphone cable, allowing RFI and EMI to leak through, or
shield wiring can begin to make intermittent contact with the signal wire. XLR pins can corrode after many
years of exposure, or solder joints break at the stress points inside an XLR barrel. Occasional cable testing
and maintenance is good practice, and worn XLR pins can often be given new life (if not past the point
of no return) by spraying liberally with a contact cleaner such as DeOxit and worked through several
insertions. It is good practice to not use a cable much longer than what is needed for the job at hand; if
a 20 ft. cable will work, little good can come from using a 35 ft. cable. Though condenser microphones
are far better equipped to survive longer or lesser quality cable runs than dynamic and ribbon mics, audio
can begin to attenuate or become contaminated beyond a certain threshold.

Not all phantom power is created equal. Though practically all preamps, mixers, and interfaces on the
market today conform to the +48v/10ma industry standard; phantom power, traditionally, has been set
as low as 10v on some legacy devices.

If in doubt, check the literature of your preamp to ensure proper phantom power is being provided.
Another point worth considering is that phantom power, being DC, can have the tendency to
attenuate over extremely long cable runs. Some engineers have observed that some demanding
condenser microphones appear to perform better when a quality phantom power source is moved closer
to the microphone.

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TIPS AND INSTRUCTIONS

If, for example, you find you are recording the WA-47jr across multiple cables or over 200+ ft. of audio
snake; investing in a quality external phantom power supply to keep closer to the microphone’s side can
be a worthy addition to your engineering toolkit. To protect the WA-47jr, always connect all microphone
cables before engaging phantom power; and for best results, give the WA-47jr about two minutes after
engaging phantom power to fully optimize, in order to get the highest quality sound. Always disengage
phantom power and allow the microphone to discharge for several moments before disconnecting the
microphone from its XLR cable and preamp.

When recording vocals, it’s a good idea to use the nicest pop filter you can afford. This not only
protects the microphone; it protects the recorded tracks by keeping plosives (a clipping that occurs
from sudden air pressure on the capsule) to a minimum. Pop filters can also be creatively used in other
situations where sudden air pressure changes can occur, which include large loudspeaker movement,
the sound hole of a kick drum, or the gap between the two brass pieces of a hi-hat cymbal. As a gen­eral rule, a higher quality pop filter will have less audible impact on the sounds passing through them;
while less expensive, improvised, or foam windscreen type filters can sometimes have a muffling effect
on high frequencies.

Microphone placement is as much an art as it is a science, and takes a great deal of patience,
attentive listening, and trial and error. The more music you record the greater instinct you will
have for knowing which microphones to first try for given situations, and how to place them.
One thing to keep in mind is that what a microphone hears will often be radically different from
what a casual observer hears when standing several feet back from where a microphone is. It’s
good practice to get down and put one’s ear close to a speaker cabinet or right in front of a bass
drum’s resonator head, and hear what that microphone is hearing from its position. Get a sense
for how different your source sounds close up, farther back, and from different angles. Begin to
move a microphone around very slowly and listen for the changes in sound that you get. Notice
how a small change in mic position can make an under-snare microphone go from bad to good.
Notice how moving a guitar cabinet mic further to the side of the center cone, or further off
axis will affect the sound.

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