NuEar

Compression for LOOK, INTRO 3, 2, and Main, Imagine 2, Imagine VS, and Imagine Products

Compression makes discrete, frequency-specific adjustments to threshold kneepoints and compression ratio per memory and channel. Compression is a decrease in gain as the input sound gets louder and threshold kneepoint is the input level where compression begins to reduce gain. Compression ratio is the degree to which loud sounds are reduced. For example, a 3:1 compression ratio indicates that for every 3 dB change in input there is a 1 dB change in output. Adjustments can be made to each individual channel, to groups of channels labeled low frequencies, mid frequencies or high frequencies, or to all channels simultaneously. The current compression thresholds and ratios per ear side for individual channels can be displayed.

Threshold kneepoint preset changes the compression thresholds in all channels simultaneously based on the Long Term Average Speech Spectrum (LTASS). The options available range from Low (Soft Speech) (50 dB SPL) to High (Loud Speech) (74 dB SPL), with two additional levels for Moderate Speech in between. Adjustments are made via radio buttons in 8 dB increments. More discrete adjustments can be made to all or select frequencies via up and down arrows in 4 dB increments.

Compression ratio adjustability is directly impacted by gain and threshold kneepoint settings. When adjusting the compression ratio, the step size will vary according to the loud gain adjustment based on the threshold kneepoint. For example, if the threshold kneepoint is low, the compression ratio step size will be very small. If increasing the compression ratio (more compression), the loud gain will be decreased above the threshold kneepoint. If decreasing the compression ratio (more linear), the loud gain will be increased above the threshold kneepoint. The minimum compression ratio is 1.0 and the maximum is 3.3.

  1. Connect and select the desired hearing aid(s) to adjust compression settings via Get Started.

  2. Click on the New Session or Load a Previous Session radio button and then click .

  3. Click Compression.

  4. Compression

    Note:  If Default Performance Values Region Open is selected via General Preferences, all numerical values display. If not selected, all numerical values are hidden.
  5. Click Click to view compression thresholds and ratios to display the numerical values for compression threshold kneepoints and ratios for all channels.

    Note:  For products where channels are grouped together, the average numerical compression threshold kneepoint and ratio values per frequency range displays.
  6. To adjust the compression time constants, click on the words Compression time constants and a pop-up window displays.

    Note:  This feature is only available for select products. The options available are Slower, Medium, and Faster. The default is Medium. If this feature is not available, continue at step 7.
  7. Click on the red, gray, or blue radio button representing the desired time constant for the right hearing aid only, both hearing aids, or the left hearing aid only.

    Note:  This adjustment is applicable for all memories.
     
    Tip:  Click Click to view gain and output values to hide the numerical values.
  8. Click on the specific memory to adjust if applicable or click to adjust all memories simultaneously.

  9. Inspire automatically defaults to a binaural Select Binaural view if applicable. To adjust only the right or left hearing aid, click Select Right Only or Select Left Only.

  10. Click on the frequency or group of frequencies to adjust.

    Tip:  To select a sequential group of frequencies, click on the beginning column header or frequency cell, press and hold Shift and click on the ending column header or frequency cell and all columns or frequencies between the two clicks will be selected, or press and hold the left mouse button and drag to the left or right until the desired group of frequencies are selected and then release the left mouse button. To select a non-sequential group of frequencies within a row, press and hold Ctrl and click on the desired frequencies. To select a specific frequency range, click the column header (Low Frequencies, Mid Frequencies, or High Frequencies) or click Select all frequencies for adjustment to select all frequencies. Selected frequencies are represented in bold (purple, green, blue, or black) on the fitting graph and teal on the table.
  11. To increase or decrease the threshold kneepoints in 4 dB increments per ear side or binaurally, click the up or down arrow keys. To increase or decrease the threshold kneepoints in 8 dB increments for all channels regardless of the frequencies selected, click on the red, gray, or blue radio button representing the desired threshold preset for the right hearing aid only, both hearing aids, or the left hearing aid only.

    Note:  The threshold kneepoint preset options available are Low, Moderate, and High. The default is Low.
     
    Tip:  Soft and loud gain adjustments can be made graphically by dragging and dropping points on the frequency response curve. These adjustments do not affect the threshold kneepoints but do affect the compression ratio settings.
  12. To increase or decrease the compression ratio per ear side or binaurally, click the up or down arrow keys.

    Tip:  Compression ratio adjustments can also be made graphically by dragging and dropping points on the frequency response curve.

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