RSS265HF-measured preformance in a TL

[dlneubec]

I thought that some of you might be interested to see what the impedance and FR of the RSS265HF looks like as measured in the TL for the HOSS project (see the HOSS thread for info on the TL configuration).

The attached graph shows the nearfield output of the woofer and TL terminus, overlaid together. The driver was measured in the center between 1/4" and 1/2" from the dust cap and the terminus was measured in the center, right at the outside wall plane.

From simply a FR standpoint (not considering distortion) I was surprised at how flat and extended the RSS265HF was. It looks pretty good all the way out to 800hz or so.

I thought this might be of interest to anyone contemplating the RSS265HF for use in a 3way or open baffle.

Regards,

Dan

[TacoD]

Wow great service! Measurments show indeed a flat response. IIRC the german magazine HobbyHifi showed a severe breakup, but maybe they used a different scale.

[joecarrow]

The sharp dip and peak look to me like breakup that you'd want to stay away from. Still, the nice level frequency response so high is quite promising. You'd need to check linear distortion to be sure.

I read that the Hi-Vi M8a behaves very pistonically until immediately before its breakup, whereas the Dayton RS180 starts to have some linear distortion problems significantly before the frequency response is noticeably out of whack. This driver's cone may be more like the M8a, which would be a very good thing.

I think the RSS drivers need a little more examination for dipole duty. Monte Kay's investigation of the 12" was helpful, but I would love to see it get into Mark K's or Zaph's hands as well.

[Dennis H]

Zaph tested the 12" but only up to 200 Hz.

http://www.zaphaudio.com/tidbits/