Dayton Audio RS28F-4



The RS28F-4 is a 4Ω tweeter from the Dayton Audio Reference series.

It offers a very sturdy build quality with a metal faceplate and a grill covering the silk dome.

It has a tuned rear chamber, supported by a rugged diaphragm assembly. It has excellent power handling and a low-distortion motor system with a lot of copper in the right places. It has a low free-air resonance and it supports very low crossover points (1200-1500Hz), depending on the used filter design.

This very nice tweeter not only measures well, but also sounds great and matches mid-woofers which need low cross-over points perfectly.

Dayton Audio Spec sheet: RS28F-4

T/S Parameters:


An average of about 150hz higher free-air resonance than manufactorer spec sheet.









Free air impedance measurement:

Sample 1 = Green

Sample 2 = Blue

The two samples are not a perfect match. The samples differ by 80Hz on the resonance frequency and sample 2 has a more damped resonance frequency peak.





Frequency measurement conditions:

The tweeter is measured mounted in a 8 liter Dayton Audio enclosure (PartsExpress part #302-701) baffle with the following conditions:

Baffle size (WxH): 19,05×30,48cm (7,5″x12″)

Driver position: Mounted on center-line with driver unit center 8cm from the top of the baffle.

Mic position: 1m distance, on tweeter-axis.

Smoothing: No smoothing applied.

0deg tweeter-axis
Sample 1 = Blue
Sample 2 = Red

Virtually the same frequency response between the two samples. At 3.5kHz the baffle diffraction is noticed as a dip in the frequency response. This dip is reduced in the off-axis measurements. The tweeter has a slightly rising top-end frequency response in the on-axis measurements.

0deg = Blue
15deg = Red
22.5deg = Green

30deg = Blue
45deg = Red
60deg = Green



Measurement setup:

  • Tweeter near-field measurement at 10cm
  • Frequency Range Tweeter: 500-10000Hz
  • Baffle size WxH: 19,05×30,48cm (7,5×12″)


The distortion measurements are done in near-field and the amplifier output level was adjusted for each driver so that the fundamental is 85dB at 1m and 90dB at 1m. This setting simulates normal to medium-high listening levels.


Sample 1:

85dB at 1m










85dB at 1m








Sample 1:

90dB at 1m









Sample 2:

90dB at 1m










The odd-order harmonics are low throughout the tweeters usable frequency range. The harmless 2nd order harmonics is a bit elevated compared to the odd-order harmonics, but is still very low. To sum up, this is a very low distortion tweeter and it can be used as low as 1.5kHz with an appropriate filter.