Use the chart below as a starting point when selecting resonator sizes for saxophone pads. The final resonator size may vary depending on the pad, key cup, tone-hole position, desired clearance and the player’s preferences.

New Series III sizing information is also included below.

Optional Maximum-Coverage Fitting Method

For professional players or musicians seeking a more powerful rock-and-roll sound similar to Junior Walker’s, you may want to fit the largest practical resonator to each pad.

1. Index the Pad

Place the pad into the key cup and make a small indexing mark on the edge of the pad with a pen. Position the mark in line with the key cup arm.

This mark allows you to return the pad to the same position after removing it from the cup.

2. Test-Fit the Pad

Press-fit the pad into the cup without using adhesive. Mount the key or keys on the instrument body and lightly “kiss” the tone hole against the pad.

Use only enough pressure to leave a visible impression showing where the tone hole will contact the pad after installation. Remove the key or keys from the instrument.

3. Determine the Maximum Resonator Size

Remove the pad from the cup and select the largest resonator that will fit inside the impression left by the tone hole.

The resonator should not touch or extend into the tone-hole contact ring. Leave approximately:

• 1/32 inch, or 0.8 mm, of clearance for a closer fit
• Up to 1/16 inch, or 1.6 mm, of clearance when more room is needed

If the player uses significant finger pressure, allow clearance closer to 1/16 inch.

4. Evaluate the Tone-Hole Position

The tone hole will often contact the pad off center. Some side-to-side adjustment may be possible by carefully bending the key. We refer to this direction as north to south.

Front-to-back adjustment, which we call east to west, is more difficult and may require elongating the mounting hole in the pad. Extensive testing did not show enough benefit from east-to-west centering to justify the additional work.

Center the relationship between the pad, resonator and tone hole as well as reasonably possible. Then select the final resonator size while maintaining the necessary clearance or reveal around the tone-hole impression.

5. Install the Resonator and Pad

Permanently secure the resonator in the pad using the appropriate staking tool.

Use the indexing mark to return the pad to its original position in the key cup, then install the pad as usual. Refer to the Saxophone Pads instructions for additional installation information.

Resonator Coverage and Performance

Using a larger resonator reduces the amount of soft leather exposed to the sound wave and air column. This may enhance sound projection, although the effect can vary by instrument, setup and player.

Larger resonator coverage may also help extend pad life by reducing the amount of leather exposed to moisture and other environmental conditions.

Testing resonators that barely fit inside the tone-hole opening, including the time-consuming process of precisely centering them, did not produce a noticeable improvement.

In 2005, a retired Selmer engineer offered the following guidance:

“You need only cover slightly over 80% of the exposed pad surface in the hole, and you have done all you can do.”

Following that principle can provide effective resonator coverage without adding unnecessary fitting time.

Common-Use Resonator Sizing Chart

Use the chart below to identify commonly selected resonator sizes for each pad size. Treat these measurements as a practical starting point and confirm the final fit using the actual pad, key cup and tone-hole contact area.

Special Bundy and Signet Sizing Notes

The sizing guidelines above reflect how Ferree’s Tools produced its pads and Selmer pads. Certain Bundy and Signet applications used larger resonators than the standard ranges shown in the chart:

Resonator #1 was used on pads up to 23.5 mm.

Resonator #3 was used on pads up to 32 mm.

Resonator #4 was used on pads up to 37 mm.

Resonator #5 was used on 41.5 mm pads.

Resonator #7 was used on pads up to 45.5 mm.

Resonator #8 was used on pads up to 49.7 mm.

Understanding the Recommended Sizes

Some technicians consider the sizes in the chart to be the largest resonators that should be used for the corresponding pad ranges, subject to the special Bundy and Signet applications listed above.

Ferree’s catalog traditionally recommended slightly smaller resonators. These more conservative recommendations allowed for unusual tone-hole sizes and provided a more universal fit across instruments from different manufacturers.

Always confirm the resonator size against the actual pad, key cup and tone-hole contact area. Instrument construction, pad-cup dimensions and tone-hole placement can vary considerably between manufacturers and models.

Allow Additional Time for Custom Sizing

Custom resonator sizing requires additional measuring, fitting and installation time. Technicians should generally allow at least one additional labor hour beyond the standard job price for custom sizing.

Installing resonators other than the standard B53R models may require approximately one more labor hour. Additional time is needed to maneuver leveling tools around the resonators without scratching, marring or otherwise damaging their surfaces.

A job involving both custom sizing and nonstandard resonator installation may therefore require approximately two additional labor hours. Include this time when preparing the repair estimate. Additional service requires additional labor and should be priced accordingly.

Selmer Series III Resonator-to-Pad Sizing

The Selmer Series III specifications are listed in the next chart. These resonator sizes differ significantly from the earlier, pre-Series III sizing guidelines, so confirm the saxophone model and pad application before selecting a resonator.