Hybrid Audio L1 Pro R2 Ring Radiator Tweeters

Up for test is the Hybrid Audio L1 Pro R2 Ring Radiator Tweeter.

Information from the manufacturer can be found here: http://hybrid-audio.com/le/

IMG_2475 IMG_2474 IMG_2482


Small Signal Parameters and Impedance

Results as measured via Dayton’s DATs measurement tool.  Which is a very little handy tool to have.  😉

  • f(s)= 639.90 Hz
  • R(e)= 3.48 Ohms
  • Z(max)= 6.84 Ohms
  • Q(ms)= 1.641
  • Q(es)= 1.702
  • Q(ts)= 0.835
  • L(e)= 0.48 mH

l1pro imp

Frequency Response

Frequency Response and the following Harmonic Distortion measurements were taken using Dayton’s OmniMic measurement system.

The frequency response measurements below are on-axis (0 degrees) and off-axis (15, 30, 60 degrees), measured at 2.83v/1m.

l1pror2 FR

To get an idea of the off-axis response vs the on-axis (0 degrees) response, I normalized the above.  What you get is the relative output level of each axis vs the on-axis level.

l1pror2 normalized

Harmonic Distortion Testing


Maroon – Fundamental

Blue – THD

Red – 2nd Order Distortion

Pink – 3rd Order Distortion

Green – 4th order

Teal – 5th order

Testing done in the nearfield to emulate 90dB and 96dB output at 1 meter.

l1pro r2 hd90l1pro r2 hd96


The Fs is measured at approximately 640hz.  To get an idea of what this means on the high-pass crossover, let’s evaluate the HD results.  At 96dB output the THD (blue) is 1.70% at 1khz.  The THD is less than 0.50% down to 1.8khz though there is a peak in THD of about 1.0% THD at 2.8kHz, which corresponds with the dip/peak shown in this region on the frequency response as well as a bump in the impedance at this same point, which means this could possibly be a chamber resonance.

Measured sensitivity is right around 86-87dB on average (note the rising response above 4kHz).  The response isn’t flat; it has approximately a 5dB rising response above 4khz, but this response is smooth. There is a 3dB dip (noted above) at approximately 2.4khz trending back up to a 1dB peak at 3.2kHz which correlates to a resonance in the impedance data. Given this is a area is largely comprised of a dip, though, the concern isn’t great.  At 30 degrees off-axis, the response is down approximately 4dB at 10khz.  At 60 degrees off-axis, the response is down approximately 7.5dB at 10khz.  Overall, the on and off-axis response looks quite good up to 10khz where the 60 degree measurement shows a strong dip centered at ~14.4kHz.  This dip doesn’t really concern me because it’s a dip, not a peak, and doesn’t show up in the other axes of measure which indicates this is not a modal issue; rather just a reflection (possibly a reflection off the surround).  While not ideal, I don’t consider it a deal-breaker.

Bottom line:  Really nice polar response.  Good use down to 2khz with a steep crossover.  Though, with the resonance at 2.4khz, I’d think 2.5khz with a 24dB electronic crossover would be a better use for these in a higher output system.  Obviously individual needs/results may vary.

PS:  If you would like to help me keep up funds for testing additional drivers, there’s a little ‘contribute’ button that goes through Paypal all the way at the bottom of every page.  Any little bit helps.

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