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ND25FW-4 , tweeter. What are + and -? Red-black?

DanielT

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I was going to plug them in later today. But there is no marking on the connectors where I will attach speaker cables. The small bass element I have is excellent with red and black maked respectively, but nothing on these tweeters. One connector on the tweeter is a little narrower, see picture. Is there a standard that the narrower is....what?
IMG_20221017_104957.jpg

IMG_20221017_104916.jpg
 
Larger terminal is positive according to Parts Express staff.


Look down this page for answered questions.

1665997734444.png
 
Larger terminal is positive according to Parts Express staff.


Look down this page for answered questions.

View attachment 237565

Larger pin is positive, smaller is negative... like this one;

View attachment 237566


JSmith
Thank you both for your help!:)

Edit:
It was as I suspected, but it's always best to check.:)
 
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Nice tweeters, ND25FW-4:)
They will be even better when I mount them in a better way. Right now I'm just test driving them.:)
Small speakers Goodman M100 that I got from a friend because they lacked a tweeter. I plugged that tweeter hole (doesn't look like that in the picture, but it's heavily plugged) and only use the 5 inch paper bass driver in them.

LD X223 crossover between those elements. I'm going to try some different crossover settings. HK 330C plus NAD C 720BEE drive Goodman M100 bass and
ND25FW-4 tweeter plus an active sub Yamaha YST 90. Right now no HP plus LP filter between sub and speaker but I can fix that.

The package in the picture. I won a bidding on a microphone stand so now I can start working with the UMIK-1.:D

IMG_20221017_120237.jpg

Speaker cable out via the port:
IMG_20221017_122247.jpg
 
Here's a Mawes that measured them:

Here is a measurement I just made. Outdoors, 2m to microphone (Line Audio OM1), 250mm*550mm baffle with beveled edges, recessed element.
Screenshot_2022-10-17_122613.jpg



Various measurements on them including distortion:
Screenshot_2022-10-17_123007.jpg



Great price on them!:)
Screenshot_2022-10-17_122826.jpg



....
But keep in mind that you can't get everything, ...not a lot of power:

Power Handling (RMS): 20 Watts
 
Touch a 9V battery to the terminals and watch the deflection. Positive always pushes out.
 
Touch a 9V battery to the terminals and watch the deflection. Positive always pushes out.
Or even 1.5 volts. 9 volts could be a bit much for this tweeter with 20 watts max and only 3.2 ohms DC resistance.
 
Or even 1.5 volts. 9 volts could be a bit much for this tweeter with 20 watts max and only 3.2 ohms DC resistance.

Even a brand new 9V battery aint going to kill a tweeter. It's only connected for a split second, just enough to see the deflection. 9V batteries are not capable of sustaining much more than a few hundred milliamps. Short circuit, out the packet, maybe 2-3A for a second or two. That's it, then they are done.
 
Good tips with the battery restorer -john! I'll try that later.:)


BUT why doesn't Dayton add a little red dot?:oops: It would make it easier instead of guessing, going by practice and/or taking out batteries?! Would it be that hard to do for Dayton, a little dab with a red marker pen and it would be done?
51dIK2gqmXL._AC_SX679_.jpg

That even if it is standard what JSmith says.

Still fascinating here. Here they tweeter again:

Parts Express C-Note MT Bookshelf Speaker DIY Kit Review.jpg


ND25FW-4
The tweeter itself, spec:
Power Handling (RMS): 20 Watts
Impedance (Z): 4 Ω
Sensitivity: 91 dB 1W/1m

But those C-notes have a only 83 dB sensitivity. Thus, the efficiency of ND25FW-4 has been dampened (with some resistors, I can guess), but despite that at 96 dB and these 20 W RMS ND25FW-4 , there will be no more distortion than:
Parts Express C-Note MT Bookshelf Speaker DIY Kit Distortion Mesaurements.png

Parts Express C-Note MT Bookshelf Speaker DIY Kit In-room Frequency Response and Distortion Me...png
 
Now I have tested and compared. I was lucky as hell! I have a pair of QLN ONE speakers. The Dayton ND25FW-4 fit EXACTLY in the hole where the existing SEAS 25TNF/T tweeter sits. I mean exactly, edge to edge with the baffle. How is that even possible? Screw holes in the same place too.:)

I know you can't (or shouldn't) change tweeters at random. There is a lot that has to be right then with crossover, sensitivity tweeter vs bass/mid, Ohms that can differ, different frequency response on/off axes and so on. Nevertheless, since I could do it so easily, switch that is, I did. It worked surprisingly well with the Dayton ND25FW-4.A nice little tweeter that Dayton ND25FW-4.:)

With a little miscellaneous fixing, maybe with miniDSP and one amp that power bass/mid and another amp for the tweeter as well as trickery with finding a sensible crossover point (plus measurement with a microphone then) that QLN ONE with Dayton ND25FW-4 could perhaps become a really good speaker.:) That IF it weren't for the fact that they have hopelessly bad, almost non existent, bass. Almost as if there was something wrong with them. When I turned the tone controls and turned on the loudness with the Luxor 7082A amplifier I tested with, they sounded okay. Those QLN ONEs are suitable to be placed in corners, or placed directly against the rear wall for bass support, that's my guess. :)

I plugged in an XTZ Tune 4 speaker on one channel and the other a QLN ONE. I set all tone controls to neutral. Then turn the balance on the amplifier. Listened to one speaker then the other. QLN ONE didn't stand a chance. XTZ Tune 4 is much better. Much more homogenous speaker with sensible FR.
(XTZ Tune 4 is an active speaker with which I tested with the amplifier not installed).


Original tweeters in QLN ONE:
(data on those in the attached images)


Sorry for the blurry pictures:
IMG_20230729_142309.jpg

No screws inserted in this picture. I sat in them later. BUT check edge to edge with the baffle.:)
IMG_20230729_142317.jpg


The Luxor 7082A amplifier, with the tone controls set when I listen to the QLN ONE. Then they sound okay. Those QLN ONE probably require proper, serious EQ to be good.
IMG_20230729_142340.jpg
 

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Now I have tested and compared. I was lucky as hell! I have a pair of QLN ONE speakers. The Dayton ND25FW-4 fit EXACTLY in the hole where the existing SEAS 25TNF/T tweeter sits. I mean exactly, edge to edge with the baffle. How is that even possible? Screw holes in the same place too.:)

Lots of tweetres have the common 104mm flange, makes it easy to swap stuff. dx25, xt25, d27, lots of scan speak stuff is the same.
 
Lots of tweetres have the common 104mm flange, makes it easy to swap stuff. dx25, xt25, d27, lots of scan speak stuff is the same.
Hooray for the agreed standard!:)

Besides, without accepted standards it would be difficult with many (most) things in today's society.Now I'm talking outside the small world of HiFi. :)
 
Not everyone plays ball, SB has lots of tweeters that are just shy of 104mm which makes things annoying when trying stuff.

I think the ND25fw is a shockingly good tweeter that frankly sounds better than just about every flat faceplate tweeter I've tried.
 
Not everyone plays ball, SB has lots of tweeters that are just shy of 104mm which makes things annoying when trying stuff.

I think the ND25fw is a shockingly good tweeter that frankly sounds better than just about every flat faceplate tweeter I've tried.
That sounds good. What you say and what I now hear from one of them. :)

What do you think about this? FatalPRO or Peerless?
I have a few different drivers and I was thinking of building a three way speaker. When I get time to do it, that is.
In general, what do you think about the potential of two Peerless SLS10 bass drivers in each box together with either:

8 Ohms Faital Pro 4FE32 and ND25fw

...or ND25fw paired with Peerless TC9FD18-08?


I'm going by what Kimmosto says about the C-C distance with the mids and tweeters. #2 in the thread:

"Minimum c-c is 1.0 x wave length and maximum about 1.4 x wave length at XO frequency " (with 24 dB filter, if I understood correctly)


Crossover point around 2.5-3.5 kHz, which I can change whenever I want because I'm not building with a passive filter. With a crossover of 3.5 kHz, the appropriate C-C distance is reduced, but I still have some room to play. Plus a relatively wide baffle, which is still will be the case with SLS 10 in the boxes and properly rounded baffle corners. Properly rounded baffle corners is maybe overkill when the ND25fw has a WG? ...But still, why not build them that way.
I will power the drivers respectively, with dedicated amps, so three amps for the solution I'm considering.


That, I hope, can be a really nice speaker.:)
IMG_20230801_195520.jpg
IMG_20230801_195458.jpg
 
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smaller waveguided tweeters seem to benefit from minimizing the baffle around them, like the chamfer on the DXT MON diy speaker design. I put one on a wide baffle and didn't really care for it.
 
smaller waveguided tweeters seem to benefit from minimizing the baffle around them, like the chamfer on the DXT MON diy speaker design. I put one on a wide baffle and didn't really care for it.
Okay BUT isn't it mostly about taste? How you prefer how the speaker spreads the sound? I mean #6 in this thread, it turns out that with a 25 cm baffle, the FR looks really good, so way not that kind of configuration, that kind of baffle width?

Wait now, the ND25FW-4 with a 104mm diameter should by itself without being mounted in a baffle be enough for crossover at 3.3 kHz, right? Wavelength at 3.3 kHz is then 104mm.
(that apart from possible baffle edge diffraction effects that may be present then)
 
Okay BUT isn't it mostly about taste? How you prefer how the speaker spreads the sound? I mean #6 in this thread, it turns out that with a 25 cm baffle, the FR looks really good, so way not that kind of configuration, that kind of baffle width?

Wait now, the ND25FW-4 with a 104mm diameter should by itself without being mounted in a baffle be enough for crossover at 3.3 kHz, right? Wavelength at 3.3 kHz is then 104mm.
(that apart from possible baffle edge diffraction effects that may be present then)

I mean I guess, but my preference and some of the research out there tells us people like speakers without dispersion errors. If one is going to expend the effort to DIY, I think it's worth doing it right. My wide baffle experience has me disinterested in wide baffle speakers honestly.

I ran the tweeter at 2500 and then tried 3000, it just didn't seem to have much width like it does on the say the c-note kit. The edge diffraction being so far from the source is probably what hurt it, on a smaller speaker the diffraction products are closer to the tweeter and tend to not be as detrimental IME. If one is going to use a WG on big baffle, large roundovers ala Grimm LS1 seem necessary.
 
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