I ran the NSD1095Ns on XT1086s at about 1.5k passive 2nd order and thought it couldn't quite deal with a 2nd order HP, mainly because it appears to have a high Q resonance down low around 900 hz that wouldn't permit clean operation anywhere near that area. It would need an LCR trap to flatten it out.
So no, I wouldn't run it that low, even with a steep filter, but with an LCR notch it could work. Above 1.5k with EQ to flatten it out, it sounds great. The 1086 tends to beam a little being a tractrix WG, but the treble Is very similar to a very nice metal dome. Obviously I'll have to see what the coax does to the response.
So no, I wouldn't run it that low, even with a steep filter, but with an LCR notch it could work. Above 1.5k with EQ to flatten it out, it sounds great. The 1086 tends to beam a little being a tractrix WG, but the treble Is very similar to a very nice metal dome. Obviously I'll have to see what the coax does to the response.
So now I have three different brands of screw on adapters (Eminence, PRV and some no name type) to make all my bolt on drivers work, but there are some let downs so far with the way the adapters run larger than the KL3021CX driver throat opening diameter. Its not just the adapters either as some screw on drivers also fit this way. Not sure why Eminence machines their screw on driver stuff to fit this way, but I'll have to at least get some measurements done to make a driver choice and get a crossover thrown together. My large 3 way project is taking much longer than I want, so I need at least something to get by while everything's in disarray.
That sounds strange. Could you measure the length? I have had no such problems with the beta coax and the eminence 1” tweeters APT50, ASD1001 and PSD2002 fits right in there. I did struggle a bit with the Selenium though but that was more on the thread size itself it seemed - not as smooth to screw in.
Here are the main 3 adapters i have. The best fitting one is the generic small 3 bolt adapter from a Chinese Ebay seller, which ended up having less than a .010" step inlet). Ironically its the best machine work of the 3, even compared to the Eminence B2SA. The worst one was the PRV plastic ABS adapter, yielding about just a little under a 1/8" (.100") lip on the throat entrance. Sadly I can't get the Ebay adapter anymore, unless there's a way to 3d print it (thread and all).
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The little waveguide is aluminum right?
I just bought this tool for a similar problem to widen the mouth of a plastic waveguide to clear the surround of a tweeter. Its tool steel so im sure it would cut aluminum, you’d need a good drill press and a jig to secure the woofer.
does 3/8“-2” Was $51.99 ……he has a couple more in stock.
I know the angle is opposite but much better than a ledge! food for thought
edit…..thinking about it, tool might not clear the threads though
edit 2 …….. unless one ground down the cutters just above the size you needed (and fit past the threads)
edit 3 ……. I suppose this would require removing the dust cap to protect the voice coil from shavings, at which point you might as well come in the topside with an automotive reamer, longer taper up to 1 3/8” I believe…….the taper would be the right way, and clear the threads on the bottom.
I just bought this tool for a similar problem to widen the mouth of a plastic waveguide to clear the surround of a tweeter. Its tool steel so im sure it would cut aluminum, you’d need a good drill press and a jig to secure the woofer.
does 3/8“-2” Was $51.99 ……he has a couple more in stock.
I know the angle is opposite but much better than a ledge! food for thought
edit…..thinking about it, tool might not clear the threads though
edit 2 …….. unless one ground down the cutters just above the size you needed (and fit past the threads)
edit 3 ……. I suppose this would require removing the dust cap to protect the voice coil from shavings, at which point you might as well come in the topside with an automotive reamer, longer taper up to 1 3/8” I believe…….the taper would be the right way, and clear the threads on the bottom.
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Thanks for the pics! Now I have a clearer understanding of the bad fit.
So, to fit exactly, what should the 1 3/8" adapter's ( inside diameter ) actually be to properly mate to the Eminence woofer ??
I'm wondering if my ( NLA ) Selenium ADM25-25 is any better.
- ( Looks like the Selenium is 25mm right-on. I.D. /// using a clear plastic see-through ruler to eye-ball the hash marks ) .
@mountainman bob - the danger of getting something into the VC gap is too risky for me grinding the excess lip. It would have been nice if it was the other way around, having the opening into the coax larger and just enlarging the adapter while maintaining the correct tapee. There is a way to protect the opening by shoving in a small squished together chunk of memory foam (the kind used to make earplugs) and letting it expand into the cavity in order to protect the VC gap. I may try that if I feel courageous enough. The other option is removing the dustcap, but again that's alot of work. The dustcap on this driver isn't the most acoustically transparent IMO. There are better ones, but finding a better one isn't as easy as it seems. No dustcap at all would be better, but that would make the cone look weird having the glue marks left over or possibly tearing the surface... not sure if they come off that easy.
@EarlK - Measurements taken (with calipers) from the coax and adapters.
PRV plastic adapter - 0.945" dia inlet, 1.075" dia outlet, 0.925" total depth, 8 deg total average
Ebay 3 bolt adapter - 0.995" dia inlet, 1.030" dia outlet, 1.010" total depth, 2 deg total average
Eminence adapter - 0.998" dia inlet, 1.050" dia outlet, 1.010" total depth, 3 deg total average
KL3012CX-8 WG - 1.025" dia inlet (give or take a few thousandth). This (or slightly smaller) is your target exit dia for a screw on driver.
The taper angles were averaged as the adapter flares weren't exactly cone shaped.
The Ebay 3 bolt adaoter would be my first choice, but it won't accomodate a 2 or 4 bolt driver. It is the most precision made piece IMO, allowing for a lot of correction to suit a specific driver exit angle, but also for initial fit. This won't be an exact science. As precise and defined as the taper in the pole piece is, the step and gap created by the VC to cone interface will affect things (negatively) far more than anything else IMO.
The Eminence would be the next best choice, depending on the driver exit angle. The PRV adapter isn't very well made. The bolt holes don't line up well on it and the main issue for me is that its plastic, so no good for a heavier driver and won't allow for a solid and secure mechanical coupling in general. The massive step in the throat it creates in the KL3012CX will certainly cause issues in the upper HF FR range. The mismatch with the Eminence adapter could be negligible, but that would have to be verified using various drivers. I suspect it will be noticeable, but the inner design of the coax itself may overshadow that considerably. We'll see...
@EarlK - Measurements taken (with calipers) from the coax and adapters.
PRV plastic adapter - 0.945" dia inlet, 1.075" dia outlet, 0.925" total depth, 8 deg total average
Ebay 3 bolt adapter - 0.995" dia inlet, 1.030" dia outlet, 1.010" total depth, 2 deg total average
Eminence adapter - 0.998" dia inlet, 1.050" dia outlet, 1.010" total depth, 3 deg total average
KL3012CX-8 WG - 1.025" dia inlet (give or take a few thousandth). This (or slightly smaller) is your target exit dia for a screw on driver.
The taper angles were averaged as the adapter flares weren't exactly cone shaped.
The Ebay 3 bolt adaoter would be my first choice, but it won't accomodate a 2 or 4 bolt driver. It is the most precision made piece IMO, allowing for a lot of correction to suit a specific driver exit angle, but also for initial fit. This won't be an exact science. As precise and defined as the taper in the pole piece is, the step and gap created by the VC to cone interface will affect things (negatively) far more than anything else IMO.
The Eminence would be the next best choice, depending on the driver exit angle. The PRV adapter isn't very well made. The bolt holes don't line up well on it and the main issue for me is that its plastic, so no good for a heavier driver and won't allow for a solid and secure mechanical coupling in general. The massive step in the throat it creates in the KL3012CX will certainly cause issues in the upper HF FR range. The mismatch with the Eminence adapter could be negligible, but that would have to be verified using various drivers. I suspect it will be noticeable, but the inner design of the coax itself may overshadow that considerably. We'll see...
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@EarlK - Pleaae measure your Selenium adapters if you get a chance. I'd be curios how those fit.
Do you happen to know of any 3D cad design guys who could come up with some kind of STL model to print based on the optimum dimensions? That may be the best option if it could be printed in reinforced PETG or even good quality PLA. i just don't know how to design the thread for the model and don't have the software either.
Do you happen to know of any 3D cad design guys who could come up with some kind of STL model to print based on the optimum dimensions? That may be the best option if it could be printed in reinforced PETG or even good quality PLA. i just don't know how to design the thread for the model and don't have the software either.
I've decided to cut down the thread height on the Eminence B2S adapters and recheck fit with the KL3012CX. It looks alot better and I've also moved the acoustic center closer together by doing so, which is a bonus. The amount to remove from the adapter thread is .200", which requires the bolt holes to be countersunk, so you will need tapered head M6 fasteners as well. It took me about an hour to modify the adapters, but now things look much better. Removal of material moves the opening further up the taper in the adapter, reducing the hole diameter by about .030" in my case. Now I can test the other drivers.
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As it stands now, I have these drivers on hand to test with - (yeah, likely have a slight case of driver hoarding, lol)
Faital Pro HF10AK
Faital Pro HF108
18Sound NSD1095N
B&C DE250 16 ohm
Celestion CDX1-1745
Celestion CDX1-1430
PRV D260MY-B
Peerless DFM2535
I have high hopes for the Faital HF10AK and HF108...
Faital Pro HF10AK
Faital Pro HF108
18Sound NSD1095N
B&C DE250 16 ohm
Celestion CDX1-1745
Celestion CDX1-1430
PRV D260MY-B
Peerless DFM2535
I have high hopes for the Faital HF10AK and HF108...
While waiting for the weather to clear up down here, I've done some quick and dirty manual FR sweeps with the HF10AK coupled to the KL3012CX.
The CD is SMOOTH AND EXTENDED well past 14 -15k and the LF cone loads the driver evenly way down to 550 hz. Everything in between is balanced with the predictable few wiggles around 10k. No weird distortions or other typical non linearities around the CD cutoff as far as my trained ear can perceive. The LF driver sounds shockingly linear with just a small bump of 2-3 dB between 3.5 - 4k as reflected in the Eminence data and measurements. Its quite a nice driver for the price if you compare it with other pro coax drivers.
This is all currently based on what my sine generator and my portable RTA with small IMM6 mic is telling me, but I'd say it's very promising until I get some more factual measurements outdoors. Its definitely enough though to keep me excited about the whole project. What blows me away is how clean the HF10AK sounds through the cone as a WG. I played some solo trumpet and alto sax stuff through it (Miles and Cannonball) with a series 20uf poly cap and wasn't expecting to hear how clean, snappy and full it sounded, specifically the reach down jnto the mid 100s of the CD without the usual artifacts you hear with coax setups like this. These drivers are pretty nice.
The CD is SMOOTH AND EXTENDED well past 14 -15k and the LF cone loads the driver evenly way down to 550 hz. Everything in between is balanced with the predictable few wiggles around 10k. No weird distortions or other typical non linearities around the CD cutoff as far as my trained ear can perceive. The LF driver sounds shockingly linear with just a small bump of 2-3 dB between 3.5 - 4k as reflected in the Eminence data and measurements. Its quite a nice driver for the price if you compare it with other pro coax drivers.
This is all currently based on what my sine generator and my portable RTA with small IMM6 mic is telling me, but I'd say it's very promising until I get some more factual measurements outdoors. Its definitely enough though to keep me excited about the whole project. What blows me away is how clean the HF10AK sounds through the cone as a WG. I played some solo trumpet and alto sax stuff through it (Miles and Cannonball) with a series 20uf poly cap and wasn't expecting to hear how clean, snappy and full it sounded, specifically the reach down jnto the mid 100s of the CD without the usual artifacts you hear with coax setups like this. These drivers are pretty nice.
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Sorry for the delay Juhazi. Broke my foot a few days ago and haven't been abe to cut out the test baffle yet. Also got distracted by the complementing LF driver I planned to use with the coax, so it can be part of the baffle layout. Hoping to resume once I can at least get my foot back into a closed shoe. I ended up ordering some Eminence KL3012LF drivers in the mean time.