In Reply to: Alternative to the EV ST350 horn tweeter on EV Sentry IV-A's posted by Geary Lyons on October 22, 2013 at 18:27:53:
Well "hat's off" to Paul E. and grindstone. I built the EV recommended EQ circuit on daughter boards, as I'm out of real estate on the main boards. Not an issue as these boards are for testing the XO. It will all go on the final boards.Here is a comparison of the EQ and non-EQ XO's:
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Note there was a 1dB difference in the pink noise reference volume between the 2 measurements. (Non EQ 87dB, EQ88dB. Close as I could get with the stepped attenuator on my pre.) They were taken on different days.
This is just adding the EQ circuit to the current XO with the 450/4700hz cuts. The measurements were taken at the listening position, so the room plays in the FR.
I will try to do 1 meter measurements in the next few days. I have coils/caps to try the 3500Hz XO point, but just now I will spend sometime listening to this configuration.
Here is a progress shot on making them prettier. I will update the restoration threads with more pics over the next few days.
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I still have to refinsh the tweeters and mounts plus I have quite a bit of touch up and final polishing, but getting close!Here is a pic of the EQ daughter board in action!
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Follow Ups
- OK? That worked!!!! - Geary Lyons 11/11/1319:48:36 11/11/13 (5)
- RE: OK? That worked!!!! - Inmate51 09:02:44 11/12/13 (4)
- RE: OK? That worked!!!! - Geary Lyons 18:59:37 11/12/13 (3)
- RE: OK? That worked!!!! - Inmate51 20:44:30 11/12/13 (2)
- RE: OK? That worked!!!! - Geary Lyons 21:40:48 11/12/13 (1)
- Getting Ready to Dive Back In! - Geary Lyons 23:49:55 01/2/14 (0)