Hygeia Electron Co. - AMT's and Planar Ribbon tweeters - Page 3

OscarS · 11th February 2020, 01:38 PM

Yes, I can sell you the RT-50021's, but pricing has increased due to them now having modified diaphragms that reduce distortion even further without affecting freq response. In a USPS medium flat rate box, they would be $216 shipped. I will post graphs of distortion reduction in an hour or so. That way you can decide if you still want them.

uncola · 11th February 2020, 03:05 PM

is this a modification that you performed on them? any details on what lead you to do that?

OscarS · 11th February 2020, 04:57 PM

Yes, I do this myself, and I had to ruin about 4 or 5 diaphragms to arrive at my current iteration, so it was kinda costly, but it was worth it IMO.

Here are some charts that tell the story of how I was trying to tame the distortion caused by a resonance I measured, thus leading to these modifications:

Overall, I liked the "lesser" modification the best, so that is what I went with.

uncola · 11th February 2020, 05:04 PM

ok can I get a pair of the 4001 then? lol

OscarS · 05:11 PM

Quote:

Originally Posted by uncola

ok can I get a pair of the 4001 then? lol

I don't have any more 4001's, sorry.

If my price is too high for the modified RT-50021's, I can still sell you a bone-stock pair for $174.95 + $16 for USPS medium flat rate shipping. If you don't plan on horn-loading them and keeping them above 2,5 kHz the stock ones are still amazing. Once you try to get away with sub-2000Hz output is really when the modification really shines. Let me know.

kingfisher · 11th February 2020, 05:57 PM

You emailed the wrong person for this purchase... Hope you are able to score a pair.

OscarS · 11th February 2020, 10:30 PM

Modifications to the RT-20051's also yielded improvements. The large distortion spike from my initial measurements I have not been able to duplicate, and I always sensed it was an anomaly, and has not reappeared since. Perhaps a weird reflection or electronics interference at the time.

Both 2nd and 3rd order harmonic distortion are reduced.

Did I mention these respond awesomely to horn-loading?

11th February 2020, 01:38 PM	#21
OscarS diyAudio Member Join Date: Jan 2011	Yes, I can sell you the RT-50021's, but pricing has increased due to them now having modified diaphragms that reduce distortion even further without affecting freq response. In a USPS medium flat rate box, they would be $216 shipped. I will post graphs of distortion reduction in an hour or so. That way you can decide if you still want them. __________________ ____________ ► Hygeia Electrical/Electron Co, AMT Air Motion Transformer and Planar Ribbons for sale here ◄

11th February 2020, 04:57 PM	#23
OscarS diyAudio Member Join Date: Jan 2011	Yes, I do this myself, and I had to ruin about 4 or 5 diaphragms to arrive at my current iteration, so it was kinda costly, but it was worth it IMO. Here are some charts that tell the story of how I was trying to tame the distortion caused by a resonance I measured, thus leading to these modifications: Overall, I liked the "lesser" modification the best, so that is what I went with. __________________ ____________ ► Hygeia Electrical/Electron Co, AMT Air Motion Transformer and Planar Ribbons for sale here ◄

11th February 2020, 10:30 PM	#27
OscarS diyAudio Member Join Date: Jan 2011	Modifications to the RT-20051's also yielded improvements. The large distortion spike from my initial measurements I have not been able to duplicate, and I always sensed it was an anomaly, and has not reappeared since. Perhaps a weird reflection or electronics interference at the time. Both 2nd and 3rd order harmonic distortion are reduced. Did I mention these respond awesomely to horn-loading? __________________ ____________ ► Hygeia Electrical/Electron Co, AMT Air Motion Transformer and Planar Ribbons for sale here ◄

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Anyone looking to use Hygeia (Airborne) AMT tweeters in their designs?	OscarS	Planars & Exotics	40	24th January 2019 05:35 PM
FS: Peerless XLS 10 830452, Monsoon Planar Dipole Tweeters, HiVi SD1.1A Tweeters	bmwparts	Swap Meet	1	13th January 2018 07:32 PM
FS: Hygeia RT-3301 ribbon tweeters	Samppo	Swap Meet	1	17th November 2011 07:21 PM
Heil tweeters from Hygeia	Ambient	Planars & Exotics	0	1st February 2011 07:30 AM
Ribbon, Planar Tweeters for Sale	IceBadger	Swap Meet	1	30th December 2010 06:31 AM

New To Site?	Need Help?
Register to Participate Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

11th February 2020, 03:05 PM	#22
uncola diyAudio Member Join Date: May 2012	is this a modification that you performed on them? any details on what lead you to do that?

11th February 2020, 05:04 PM	#24
uncola diyAudio Member Join Date: May 2012	ok can I get a pair of the 4001 then? lol

11th February 2020, 05:57 PM	#26
kingfisher diyAudio Member Join Date: Feb 2010 Location: Eastern Ontario CA.	You emailed the wrong person for this purchase... Hope you are able to score a pair.