Instructions for The NCS Fluency Enhancer

The National Center For Stuttering is pleased to present its Fluency Enhancer. Developed and manufactured in the US, the Enhancer is the recipient of several patents and the only device with FDA approval for the treatment of stuttering.

In this box you will find the following:
  1. A Fluency Enhancer.
  2. A small screwdriver.
  3. A large headset.
  4. A small headset.
  5. An AC adapter.
  6. This manual.
  7. A Motiv-Aider.
The large headset has one red plug and one black plug. The small headset has one plug.

The warrantees for the headsets are covered by their respective manufacturers.

Look at the Fluency Enhancer, more specifically, the endplate with the knobs and sockets on it.

From left to right are the following:

First, a black knob marked DELAY that controls the amount of the speech delay sent to the headsets. The range is from a 30 milli-second delay to one of 200 milliseconds. For most, a delay between 70 and 125 is typical for producing fluent speech.

Next, a socket labeled MIC. It is into this socket that the red plug from the large headset will be inserted.

Next, a small socket labeled CELL. It is into this socket that the plug from the small headset will be inserted.

Above the small socket is a red light that is on when the Enhancer is operating.

Next, a socket labeled EAR. It is into this socket that the black plug from the large headset will be inserted.

Finally, a black knob that controls the VOLUME of the sound sent to the headset.

To the left of the endplate on the long side of the Enhancer is a single socket with a pin in it. It is into this socket that the AC adapter plug will be inserted. The adapter is for use in a fixed location, such at a desk, and shuts off the internal battery, thus conserving its power.

On the opposite long side is a slide switch, which turns the Enhancer on and off and beneath it, a socket which can be used for hooking up the Enhancer to a telephone. For most situations involving the phone, however, the phone socket will not be used.

Look at the back of the Enhancer. There are two adjustable controls. A small screwdriver is provided to make these adjustments. The right control is marked, PITCH. This controls the amount of frequency shift that can be obtained. The PITCH can be raised or lowered by over an octave. In most instances we want a lower shift that sounds like a completely different person.

The other screwdriver-operated control on the back of the machine is labeled GAIN. This controls the sensitivity of the microphone for either headset. That is, we can make either headset microphone more or less sensitive to sound. It has been set at the factory and generally does not require adjusting unless you try a different microphone.

Note there is a clip on the back of the Enhancer for attaching it to a belt or waistband.

The last item on the back of the enhancer is the battery compartment, which can be opened by pressing on the ridges and sliding the plate in the direction indicated by the arrow. The Enhancer uses a standard 9-volt battery, which should provide between 25-30 hours of continuous operation before needing replacement. Rechargeable 9-volt batteries plus a charger can be purchased from Radio Shack, should you wish not to have to replace batteries.

Using The Fluency Enhancer

It is best to use the large headset to become familiar with the operation of the Enhancer. So unpack it and insert the two plugs into their respective correct sockets on the endplate and put it on. Note that there is a built-in volume control and on-off switch in the cord attached to the headset. For our purpose the volume will always be set to its highest level and all adjustments to volume will be made on the fluency enhancer. Similarly, we will turn the system on by using the on-off switch on the enhancer rather than the on-off switch in the cord going to the headset. Note that the microphone can be moved to any position. Place it to the side of the mouth.

Now move the slide switch on the side of the Enhancer up, turning the machine on. Note the red light goes on, signaling the machine is operational.

The first thing we will adjust is volume. Start speaking and adjust the VOLUME knob on the endplate of the enhancer to a level which is comfortable.

We are now ready to adjust the pitch or frequency shift. Using the screwdriver provided, turn the PITCH control on the back of the machine to the left as you experience a lowering of your voice. Adjust the pitch until the voice you are hearing in the headset sounds like James Earl Jones or Darth Vader. Don't go to the extreme of the low pitch range. Think of the low-pitch voice as a friend that accompanies you as you speak.

**** Before doing anything else, read out loud to someone from a book, magazine, newspaper, etc, for several minutes to acclimate yourself to the sound of the low-pitch voice. Experiment with the range of low pitches, selecting one you like best.

Now turning to the end plate or top of the machine, turn the left black knob to adjust the amount of speech delay. The Fluency Enhancer comes with the delay set at approximately 30 milliseconds. Rotate the knob so the point is facing the standard 70 millisecond delay. Notice that you suddenly experience something unusual with your speech. The delay creates an automatic slowing, with the greater the delay, the slower the speech!

Your natural tendency will be to want to raise the loudness of your voice. Try not to do this. Instead, soften your voice as you focus your attention exclusively on the low-pitch voice.

**** Before doing anything else, read to someone for several minutes with the delay set to 70 to acclimate yourself to it. Keep your voice very soft. Then try adjusting the delay to find one you like best and which also produces the greatest degree of fluency.


As you read under delay, I want you to make a special effort to slow the first word of each sentence. Slowing the first word is extremely important because there is no sound before the first word to start the Enhancer. Because of this it is important to give the Enhancer a chance to work by starting each sentence slowly. Here are 2 tips to help you. 1) If the first word is a monosyllable, think of it as having a comma after it. Putting the comma in puts the brakes on you. For example: Read this sentence out loud. 'I see the dog'. Now read it like this: 'I, see the dog'. The difference is clear. Tip 2) If the first word is a multi-syllable, think of it as in a dictionary, where the syllables are separated by dashes to indicate syllabification. 'Yes-ter-day I took a walk' would be a good example. Practice this, sounding as natural as you can. Also, since the first word is slowed, hide it a bit by making it the softest word in the sentence and not the loudest. Beginners tend to make it the loudest; we don't want you to be a beginner. After the first word, you are to speak the rest of the sentence completely normally in every respect. Practice this as you read to become comfortable slowing the first word of every sentence. One final point: In so far as your brain is concerned, every time you take in a new breath, what follows is a new sentence. The brain does not pay attention to punctuation. So, in a long sentence, if you take a breath in mid-sentence, the word that follows must be spoken slowly since it has become the first word of a new sentence.

When you are weaned off the device, the slowed first word will be extremely important in maintaining your fluency - so learn it now.

Adjust the amount of delay to one that is comfortable but also one which clearly slows the speech of your low-pitch voice (typically, somewhere between 70 and 120 on the DELAY dial). When you have found such a setting, leave it, and continue reading.

I would like you to read each day since reading speeds the process. Read anything that interests you. Read sports, cook books, homework, comic books - anything, as long as you remember to read softly and slow the first word of each sentence. Pointer: Choose several pages and, with a read pencil, put a comma after mono-syllable word start and underline each syllable of the first word when the sentence begins with a multi-syllable word. Practice reading these pages, paying attention to the visual cues for slowing. Do not use excessive emphasis when slowing first words. Say them naturally, say them softly, say them slowly. Speak them, do not intone them. Everything should be spoken as naturally as possible, while slowing the first word of each sentence. Naturalness is the key.

After a while, slide one earphone off your ear, leaving it on your temple. Now you are experiencing the low pitch, delayed voice in only one ear. Because of this you may have to increase the amount of the delay slightly to get the same effect. You may want to use this arrangement for phone calls.

Now try the smaller headset.

Turn off the Fluency Enhancer by moving the slide switch down.

Remove both plugs from the large headset and insert the single plug from the smaller headset into the socket under the light, the one marked CELL.

Turn the Enhancer on and place the small earpiece in either ear. Readjust the volume on the enhancer so the volume is the same as before. If there is insufficient volume, adjust the gain control on the back of the machine.

Continue reading with the small headset, always paying attention to the low pitch, delayed voice and the soft, slow start. Remember that since you are using only one ear, you may have to increase the delay somewhat to have the same effect. The frequency shift can be left as is.

Begin now to have conversations with friends, family, etc. Remember to keep the voice very soft and try to slow the first word of each sentence! Try it on the telephone as well.

If you experience difficulty, contact the Center and Dr. Schwartz will help you.

The special helpline number is: 1-212-532-4445.

Use the Motiv-Aider after the first month of practice to facilitate transfer of Fluency Enhancer Speech into real world speaking situations. Set the Motiv-Aider to go off once every 15 minutes. Wear it for several hours each day. When you feel its prompting vibration, speak in the manner to which you have been conditioned to do by the Fluency Enhancer.

With the OK of your physician, you can begin implementing the nutritional suggestions.

Gradually, after a while, you will stop anticipating difficulty speaking. At that point, you can begin to lower the sound in the headset. After a period of time, the sound in the headset will be so low it will be barely audible. At that point you will no longer need the Enhancer and transference will have been complete.

As a protection, it is always a good idea to speak out loud for 20 minutes each week, using the Fluency Enhancer. This will tend to prevent any slippage of your conditioning.

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