neodymium Seas tweeters

[Hans L]

The Madisound board seema clueless about these drivers, so I'm asking here: I'm looking for any experience with any of these neodym 25mm dome Seas tweeters:
http://www.seas.no/seas_line/tweeters/H614.PDF
http://www.seas.no/seas_line/tweeters/H623.PDF
http://www.seas.no/seas_line/tweeters/H615.PDF
http://www.seas.no/seas_line/tweeters/H625.PDF

I believe they will sound alike, apart from some glitched due to the faceplate dimensions. The motor seems to be the same for all four tweeters, just the faceplate and the dome material is different. These tweeters have been around for quite osme time, do I would think someone here must have heard/tried them.

Thanks

 

[Variac]

well, some were designed for autos which is probably why home audio people don't know much about them.

The ones with smaller housings would seem to be perfect for making coaxials out of regular woofers, by removing the dust cap and attaching them to the pole piece.

 

[Hans L]

well, some were designed for autos which is probably why home audio people don't know much about them.

Hi Variac,
I think it would be more accurate to say that in this case 'home audio people don't know much' But I know what you mean. The little round ones look like cheap $2.45 car tweeters, but judging from the specsheets they seem to be pretty good. I was hoping for some hands on info.

 

[Zaph]

The Madisound board seema clueless about these drivers, so I'm asking here: I'm looking for any experience with any of these neodym 25mm dome Seas tweeters:
http://www.seas.no/seas_line/tweeters/H614.PDF
http://www.seas.no/seas_line/tweeters/H623.PDF
http://www.seas.no/seas_line/tweeters/H615.PDF
http://www.seas.no/seas_line/tweeters/H625.PDF

I believe they will sound alike, apart from some glitched due to the faceplate dimensions. The motor seems to be the same for all four tweeters, just the faceplate and the dome material is different. These tweeters have been around for quite osme time, do I would think someone here must have heard/tried them.

Thanks

Hello,

I've used the H623. It needs to be crossed over over very high and steep to avoid sounding harsh. Considering that, it's roughly about as good as any other small neo tweeter.

If this is for a car, consider the LPG 26NA. I've used this and I think it's a better sounding tweeter. Same crossover issues however. 4th order acoustic at 3Khz is about the lowest I would go.

If this is for home usage, consider the Peerless 811435. It's impressively smooth with low distortion. Better than the rest of Peerless' crappy tweeters too, if you can believe that. And then of course consider the small flange Morels.

 

[5th element]

Out of all those tweets id go for the second on the list, the H623.

All of them seem to be pretty much identical with regards to power handling, resonance frequency, xmax. Obviously the faceplates are different. But all the tweeters seem to have pronounced ridges in the waterfall plots and in sensative areas too, at about 2k.

The 623 doesnt have any off these so for that reason alone I would pick the 623. Dont cross too low with these either. Although the resonance is really well damped I wouldnt go below 3khz with steep slopes. You would need a driver with a pretty large voice coil to mount them coaxially, 47mm voice coil probably and thats cutting it rather close. Plastic faceplates will make sculpting easy, but you wont be able to reduce the diameter anymore then then 45.9mm, but you will be able to remove the square bits on the non circular ones.

Infact I cant find any driver you could mount these on, in the middle of the voice coil. The only ones are the peerless XLS and some other large drivers not suitable for midrange application.

The only company that springs to mind is dynaudio, but in that case you would not want to damage the driver and probably partner it with a better quality tweeter.

 

[Variac]

I think Morel makes some smaller drivers with 75mm voicecoils -which look a lot like the Dynaudios! These were used in the Eggleston speakers I believe. Since the tweeters are only about 50mm, that allows a bit of tapering of the piece that holds the tweeter, like a phase plug. Too bad they really don't seem to be top of the line..

 

[Hertzschmerz]

Infact I cant find any driver you could mount these on, in the middle of the voice coil. The only ones are the peerless XLS and some other large drivers not suitable for midrange application.

Monacor SPH-200KE has a 50mm diam. voil coil and can be used up to 2 kHz. Together with the horn loading effect of the woofer cone... Any volunteers?

 

[Hans L]

Re: Re: neodymium Seas tweeters

I've used the H623. It needs to be crossed over over very high and steep to avoid sounding harsh. Considering that, it's roughly about as good as any other small neo tweeter.

I read your comment on th TM025F1 at your website. Thanks for the warning. All of a sudden these little neo's don't look as good.

If this is for home usage, consider the Peerless 811435. It's impressively smooth with low distortion. Better than the rest of Peerless' crappy tweeters too, if you can believe that. And then of course consider the small flange Morels.

You got my attention with the Peerless tweeter! It's very cheap (which actually makes me hesitate). I hadn't noticed this tweeter before. Btw, I thought the 811815 sounded pretty good considering its price. For the sake of reference, how does the 811435 compare to the Seas tweeters you've used in your projects? I've heard quite a few Seas tweeters (like you I really like Seas), but only the Excel 001 and 002 for extensive periods.

I'm currently experimenting with modifying the frontplate of a couple of Vifa XT19's, also a version with a short horn in it... if that doesn't work out, I will need a high value and quality alternative with a small faceplate. The Peerless you mentioned could be it.

Thanks!

 

[5th element]

I think Morel makes some smaller drivers with 75mm voicecoils -which look a lot like the Dynaudios! These were used in the Eggleston speakers I believe. Since the tweeters are only about 50mm, that allows a bit of tapering of the piece that holds the tweeter, like a phase plug. Too bad they really don't seem to be top of the line..

The Seas tweeter isnt really top of the line either. I would be hesitant about removing the dustcap on a 5-6" driver thats 3"+ in diameter itself, clearly this represents a much larger portion of the radiating area then a standard dustcap over a 25-33mm voicecoil. It could make quite a difference to the drivers frequency response and maybe muck the whole thing up. Polepiece needs to be vented so the tweeter wires can go somewhere.

I would personally just prefer to buy the TPX/PP 6.5" seas coax unit, it would probably come out cheaper (those morels are not cheap) and are guaranteed to work. However if you like a challenge and this is more to do with you wanting to have a go, then by all means go for it.

 

[Variac]

Actually I meant that the tweeters weren't top of the line.
I agree that this project would be for those of the experimental sort.
I am mighty tempted by the Seas Coax- you have me figured out there!BUT I'm wondering if having the tweeter extended a few inches out from the polepiece might sound better than using the big cone to kind of horn load the tweeter as in the Seas Coax.

 

[Zaph]

Re: Re: Re: neodymium Seas tweeters

For the sake of reference, how does the 811435 compare to the Seas tweeters you've used in your projects?

Like most neo tweeters, it is high Qts and does not have very good low frequency ability. I've used it 2nd order at 3.2khz and 4th order at 2.7khz. Second order is achievable with a single cap and a notch filter. You can get to 4th order using 2 caps and a coil. Probably this coming weekend I might do another design with it. The 811815 is actually a lesser tweeter with frequency response problems and a top octave that is rolled off a bit too much.

Just about all standard flange sized Seas tweeters have lower energy storage in the critical 2khz to 6khz range, which gives a greater clarity and transparency. But still, the 811435 is a lot better in this regard than many other neo tweeters. If small and cheap are in the requirements, this tweeter fits.

Here's a cumulative spectrum decay for the 811435.

 

[Zaph]

And for comparison, here's the CSD for a Seas 27TDFC. Notice the lack of light red and orange in the 2khz to 6khz region, and in fact at frequencies below 2khz.

 

[Hans L]

Great! Thank you for those measurements! The plots indicate quite a difference in soundquality, which makes my decision relatively easy. Seas neo are out, the Peerless probably too... even if it is much better than its competitors. Too bad though. Morel would probably be a high quality alternative, but my wallet thinks otherwise. I think I will be better off modifying the standard faceplates of 'conventional' tweeters. Back to the workshop, but first I need to get some sleep
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Trying to dream of clean CSD plots