Congratulations on your purchase of The Sound Professionals battery module. This power supply will allow you to get the best possible performance from any microphone that uses 9-12 volts bias power, also know as ‘plug in power’.

The battery module is a self-contained power unit. To access the battery (included and already installed) for replacement, simply remove any screws that are installed on the cover of the battery unit and remove the cover (on the -8, -10, -11 and -12 models, the cover slides off). The battery can now be lifted out and replaced when necessary. It is recommended that you change the battery at least once per year or more often if needed. See our website for battery run times on each model and labeling of inputs and outputs.

Bass Roll off models only

Before making your first important recording, it is suggested that you experiment with your new microphones and battery unit a bit. There are 7 different bass roll-off frequencies to choose from: 16Hz, 69Hz, 95Hz, 107Hz, 160Hz, 195Hz and 888Hz. You will find that different recording situations require a different bass roll-off frequency to produce the best results, depending on many factors such as the type of microphone you are using, the venue itself, shape of the room, your position in the room, speaker placement (if any), and many other factors. You should experiment with the different roll-off frequencies to see which one(s) produce the sound that you like the best. To set the roll-off frequency, set the switches according to the following chart:

Your desired Roll-off Frequency                                   These switches set to the “off” position (also known as "open" on some modules)

16Hz (no roll-off)














It is usually desirable to have the left and right switches set to the same frequency; however, they can be set independently if desired. The best way to determine the best setting for a given recording situation is through trial and error, starting off with the 16Hz setting and working up in frequency until the desired amount of bass is achieved in your recording. Remember, setting the switches to higher numbers removes more bass from the recording.

Here are some general guidelines: For louder, bassier situations, try higher settings; for smaller, quieter situations, use lower settings. If the venue has bad acoustics, use higher settings; for venues with better acoustics, use lower settings. If you are using cardioids, use lower settings; for omnidirectional mics, use higher settings (cardioids reduce bass somewhat when compared to omni’s as a function of their more directional pickup pattern). The audible differences between settings are subtle, so you won’t destroy a recording by using the wrong setting. There is no ‘right’ setting…what sounds right to your ears is ‘right’.

Preparing to make a recording

Using the module with a Sound Professionals microphone

If you are using the battery module with one of our microphones, simply plug the microphone’s connector into the battery module’s input jack. The microphone is now receiving power from the battery module, and you are ready to proceed. This module is NOT to be used with the SP-MICRO series microphones.

Using the module with other microphones

If you are using the battery module with a microphone other than a Sound Professionals microphone, the procedure for its use is the same as noted above. Be sure the microphone is designed to use at least 9-12 volts DC bias power (or plug in power) and has a 1/8” stereo phone plug.

Now you may plug the 1/8” stereo output cable into your recorder using one of the following procedures:

1.    If you are going to record very quiet sounds, (nature sounds, human speech, chamber music, meetings, etc.), it is suggested that you use the microphone “in” jack of your recorder using the -20dB setting (if you have one). This should produce excellent results with these types of sources. You may find it necessary to change to the different -dB setting if you have to turn the recording level controls up near their maximum settings at the -20dB setting. Important note: If you DO NOT have a mic sensitivity switch or setting on your recorder (some SONY MD recorders), you may need an optional attenuator cable for sounds that are too loud for the mic input and not loud enough for the line input. This cable is available at your local Radio Shack or on our web site part # SP-ATEN-1. If you have the level control option, you don’t need the cable-the level controls perform the same function more effectively.


2.    If you are going to be recording loud sounds (rock concerts, full orchestras, close miked instruments, etc.), it is suggested that you use the “line in” jack of your recorder. This will produce excellent results with these types of sources.  Rule of thumb is to always try the line input first. If you can get levels strong enough to use the line input-use it, as you will generally get cleaner recordings using the line input.


You may now begin recording, following the directions provided by your recorder’s manufacturer. After a few minutes of recording, stop the recorder and listen to the recording you have just made. Adjust the microphone placement, recording levels and the bass roll-off frequency as needed. Repeat this procedure until you are satisfied with the results. You are now ready to make that once-in-a-lifetime recording!

Remember to unplug the microphone from the battery box when not in use to conserve battery power. As long as the microphone is plugged in, the module is “ON”.

Level control model only

If you have the level control option, you will be able to adjust the output of your microphones at any time, even while recording. This will have the same effect as adjusting the recording level on your recorder or lowering the mic sensitivity.

When you are ready to begin recording, follow the directions provided by your recorder’s manufacturer to set your recorder into the “record” mode. Set the recording levels on your recorder at or near maximum gain.  While viewing the record level meter on your recorder, adjust the level controls on the battery module to achieve the desired recording level.  The level controls may be adjusted at any time while recording. After a few minutes of recording, stop the recorder and listen to the recording you have just made. Adjust the microphone placement, recording level and the bass roll-off frequency as needed. Repeat this procedure until you are satisfied with the results. You are now ready to make that once-in-a-lifetime recording!

Care and Maintenance

Your Sound Professionals product has been designed and manufactured to provide a lifetime of trouble-free service. When necessary, you may wipe the battery/filter module with a soft cloth.

Questions and help

If you have any questions regarding the use of your microphone system or require help with these instructions, please feel free to call us at 1-800-213-3021.


The Sound Professionals will repair or replace, at our option, for a period of two years from the date of purchase, any Sound Professionals manufactured which in normal use has proven to be defective in workmanship or material, provided that the customer returns the product to us prepaid with proof of purchase. The Sound Professionals will not be responsible for any asserted defect which has resulted from normal wear, misuse, abuse or repair or alteration made or specifically authorized by anyone other than The Sound Professionals. Under no circumstances will The Sound Professionals be liable for incidental or consequential damages resulting from the use of this product. This warranty is The Sound Professionals sole warranty and sets forth the customer’s exclusive remedy, with respect to defective products; all other warranties, expressed or implied, whether of merchantability, fitness for purpose, or otherwise, are expressly disclaimed by The Sound Professionals.