I find it impossible to work with the Neo3 PDR...

[fjhuerta]

Hi all!

I've been meaning to ask this question for a long time...

I've worked twice with the Neo3. I know it's a highly regarded tweeter, used in lots of implementations. Including MartinLogan speakers.

Thing is, I hate it. I can't seem to work with it at all.

I find it has a certain "sound" to it. I can't quite fully explain it, but lower highs just don't sound right.

I've never been happy at all with it. Everytime I've used domes, I've been satisfied. Never with the Neo3, in 3 different designs I've built.

Right now, I got back an old set of speakers using Focal 5N421 woofers and a Neo3 in an MTM configuration. I thought I'd give another shot to it.

Can't do it. It just sounds... weird.

Is the Neo3 a difficult tweeter to work with? I've used it flush-mounted and surface mounted, with metal woofers and poly ones, MTM, 2.5 ways...I've never been able to do anything I like with it.

I've attached a pic of its measured FR, on a 1.20 meters x 18 cms baffle. For the record, I've tried it in 3 different baffles, and each and every one measures equally awfully.



I'm stumped (BTW, I've used 5 different tweeters, so I don't think it's a manufacturing defect).

[dlr]

Very possibly baffle related

Is the Neo3 a difficult tweeter to work with? I've used it flush-mounted and surface mounted, with metal woofers and poly ones, MTM, 2.5 ways...I've never been able to do anything I like with it.

I've never actually used it, so I'm making a bit of an assumption.

I've attached a pic of its measured FR, on a 1.20 meters x 18 cms baffle. For the record, I've tried it in 3 different baffles, and each and every one measures equally awfully.

Besides the driver's native on-axis frequency response, it may have better lateral dispersion than typical dome tweeters. This will show up as differing, possibly worse diffraction signatures on the various baffles.

If you haven't yet tried diffraction control through baffle layout or can't alter the diffraction signature (don't have or don't want to use felt or a roundover), then I would suggest using either a slightly off-axis measurement, say 15 degrees left or right, to design. You could also make a single response file by using an average of several measurements that will tend to "mask" the diffraction. This should result in a somewhat smoother power response that may be the reason for your problem.

Using only the on-axis measurement when there is significant diffraction is very problematic.

[cjd]

Yeah, the rocky behavior sure looks like diffraction... check out Dave's pages on dealing with that.

C

[hdspeakerman]

Neo 3

I cannot speak to the issues you have with this driver but I can say that I have enjoyed it very much and have had several visitor comment about how much they liked the Neo 3 presentation. I am posting a link to designs by Lou C. He has quite a bit of experience with the Neo 3 and IMHO has been very successful with it. The "Cryolite" is the one I built.
Howard

http://www.lonesaguaro.com/speakers/

[Biff]

I am using it in an mtm with pl18s and got very smooth response, 2nd order @ 3k (IIRC) DM crossovers. He commented on the excellent vertical dispersion as wellas good horizontal, but said there was some small rippling due to cavity effect using the BG surface type mount plate, but that disappeared and gave what he felt was a nice clean power response.

[fjhuerta]

Thank you very much for your help.

I'll experiment this weekend with felt around the tweeter. I wonder how much effect that will have - hopefully a lot.

I still wonder whether I just dislike the sound of the Neo. I've read that it sounds pretty much like the RS28. To me, they sound completely different - the RS28 is completely transparent, while the Neo has a slightly nasal quality, IMHO.

I wonder what it is that I'm doing wrong.

[Jed]

Thank you very much for your help.

Neo has a slightly nasal quality, IMHO.

I wonder what it is that I'm doing wrong.

I wouldn't dismiss the mids contributions to these tonal imbalances. Remember the presence region 1-5k is the sum of both parts- mid/tweeter.

[kestrel]

You just don't like the BG NEO3s. I'll take them off your hands for 1/2 price. :T

[fjhuerta]

You just don't like the BG NEO3s. I'll take them off your hands for 1/2 price. :T

Strangely enough, I gave them to a friend yesterday. He wanted to use them because of their flat impedance (he's a tube guy). Hopefully, he'll find a use for them. I suspect I'm crossing them too low for their own good, and since all I own are metal woofers at the moment, this is not going to change.

I replaced them with the Madisound MB Quart titanium tweeters. Quite probably, I'll find them easier to work with. Hopefully, they'll like a 2 KHz 6th order crossover.

[gitarretyp]

Out of curiosity, were you using them with or without one of the face plates?