Kappalite coaxials!!

[5StringPocket]

Sorry if it came across as being snarky or rude. My point was that the Altecs look to come as a complete coaxial speaker, where the Eminence KL30XXCX speakers are the low frequency drivers only and need to be paired with a tweeter in order to produce a full range response.

Correct, and this picture shows the high frequency driver screwed into the back of the woofer's magnet structure.

 

[takeout]

This may be insane to consider, but could the 15" drop into an old Mesa Diesel 1x15 (the TL-606 ripoffs) and perform well, until such time as I could get around to building a proper (and lighter) box for it?

 

[Passinwind]

This may be insane to consider, but could the 15" drop into an old Mesa Diesel 1x15 (the TL-606 ripoffs) and perform well, until such time as I could get around to building a proper (and lighter) box for it?

FWIW, there was never any ripoff going on, E-V greatly encouraged OEM use of that design. They sold a whole lot of drivers thanks to giving those build plans away too.

My experience with the KL 3015LF in a 606 box was that the port sizing in my preferred stepdown mode config lead to nasty chuffing. I haven't run the numbers on the coax driver yet, but I'd give that a little extra attention before jumping in, at least.

 

[takeout]

Sorry, @Passinwind - was meant to be tongue in cheek.

My understanding is that these coax ones have more in common with the non-LFs than the LFs. Am I mistaken?

 

[takeout]

(Have owned LFs in the past, I remember how big a box and port area they wanted to see...)

 

[Passinwind]

Sorry, @Passinwind - was meant to be tongue in cheek.

My understanding is that these coax ones have more in common with the non-LFs than the LFs. Am I mistaken?

All good. I haven't tried modeling the coax one, but the long Xmax and low-ish sensitivity rating looked closer to the LF than the non-LF one at first blush. And any time I've used long throw woofers in DIY designs I've found paying extra attention to port velocity to be useful.

Still very much hoping that Duke gets a chance to work his craft on some cabs with these drivers, but I know he's had a lot of life swerves going on in the last year. I've had to swear off DIY cab building myself, but I'm looking forward to seeing what you come up with!

 

[agedhorse]

There was no rip off on the TL cabinets. In fact we were probably the largest user of raw EV drivers after EV themselves. The TL design was available to any commercial builder using the EV drivers. IIRC, they were not allowed to be used commercially if you did not use their drivers however. I don't recall any limitations for personal builds.

 

[Passinwind]

There was no rip off on the TL cabinets. In fact we were probably the largest user of raw EV drivers after EV themselves. The TL design was available to any commercial builder using the EV drivers. IIRC, they were not allowed to be used commercially if you did not use their drivers however. I don't recall any limitations for personal builds.

When I was looking at doing some commercial builds in the mid 80s the E-V rep just asked me not to call them TL-606s. He suggested TP-606 as an acceptable nomenclature, but the Passinwind TP-606 might be a bit much, even for me I reckon.

 

[agedhorse]

When I was looking at doing some commercial builds in the mid 80s the E-V rep just asked me not to call them TL-606s. He suggested TP-606 as an acceptable nomenclature, but the Passinwind TP-606 might be a bit much, even for me, I reckon.

I think that's the reason we named the cabinets the way we did.

 

[pie_man_25]

There was no rip off on the TL cabinets. In fact we were probably the largest user of raw EV drivers after EV themselves. The TL design was available to any commercial builder using the EV drivers. IIRC, they were not allowed to be used commercially if you did not use their drivers however. I don't recall any limitations for personal builds.

As far as I know the designs were pretty freely given away. Kinda hard to enforce what somebody does with that design short of not publishing them so openly in the first place as long as they're not selling the work. That being said, I'm not sure why they'd have been too worried about it - there was probably a boardroom meeting or several about it before they decided to publish it anyways.

 

[agedhorse]

As far as I know the designs were pretty freely given away. Kinda hard to enforce what somebody does with that design short of not publishing them so openly in the first place as long as they're not selling the work. That being said, I'm not sure why they'd have been too worried about it - there was probably a boardroom meeting or several about it before they decided to publish it anyways.

It wasn't a problem using the designs if you were also using their drivers, what they didn't allow (and I don't know how they enforced it, but I understood that they did) was using their design with other non-EV drivers. They owned the design, they were copyrighted and the drawings I have (somewhere in my archives) had this disclaimer printed right on the drawings.

These days it's not going to matter, they are way too old for any protections to remain on them.

 

[pie_man_25]

It wasn't a problem using the designs if you were also using their drivers, what they didn't allow (and I don't know how they enforced it, but I understood that they did) was using their design with other non-EV drivers. They owned the design, they were copyrighted and the drawings I have (somewhere in my archives) had this disclaimer printed right on the drawings.

These days it's not going to matter, they are way too old for any protections to remain on them.

Sorry big guy, I meant more on the non-commercial home-builder end of things. It's my understanding that they were pretty widely distributed. Enforcing, or at least having a reasonable expectation to legally enforce the use of their designs when used on a commercial basis would have probably been straightforward enough. What I'm intending to say is that it's hard to realistically enforce what a guy might do in his garage on a completely non-commercial basis, at least with regards to using EV drivers in an EV cab.

 

[agedhorse]

I don't recall any limitations on non-commercial use, just commercial.

 

[pie_man_25]

I don't recall any limitations on non-commercial use, just commercial.

And I'm just trying to talk about reasons as to why

 

[5StringPocket]

… continuing the Eminence KL3015CX-8 cabinet build. Time to wire up the jacks, switch, crossover, and L-Pad. I imported a picture of the components into Visio and added the wiring. It saved time and turned out better than expected. Most of the green wiring is white but green shows up better on the light background. 16 gauge stranded wiring was used except for two 14 gauge leads to the woofer and all wires were labeled.

One thing to mention is that inductors in close proximity like this should be mutually perpendicular to minimize unwanted coupling. Think of the cabinet width, height, and depth like X, Y, and Z axes. The driver voice coils line up with the Z axis and the crossover is mounted with the solid core inductor vertical along the Y axis and the air core inductor sideways along the X axis.

I used 3.5" mineral wool batts to stuff the inside before mounting the electronics. Here is what it looked like before mounting the drivers:

This turned out to be a failed experiment. Stuffing that mineral wool into place was a real hassle and when I tested the cab it had unacceptable vibrations, much less volume than expected, and just sounded choked. Not good, so I opened it back up to find the mineral wool was contacting the back of the cone (acting like a mute) and the crossover was not fully secured on its standoff mounts. I removed the mineral wool, tightened the crossover mounting screws, and added a 2nd layer of acoustic foam to the back. Here is what it looked like before reassembly:

 

[agedhorse]

What exactly are you trying to achieve with the switch. It looks a LOT more complicated than necessary.

My hunch is that it will sound a lot better without the iron core inductor used as a 1st order LPF, simply short across its terminals. I don't think that woofer needs it, or benefits from it.

 

[4Mal]

Yep..That cab looked way over stuffed. I would try a thin skin of poly bat and see if that is enough. i think the last stuff I used was quilt stuffing from Wally World. Maybe .5 to.75 thick. 3m spray adhesive to tack it down.

 

[5StringPocket]

What exactly are you trying to achieve with the switch. It looks a LOT more complicated than necessary.

My hunch is that it will sound a lot better without the iron core inductor used as a 1st order LPF, simply short across its terminals. I don't think that woofer needs it, or benefits from it.

I wired the switch to avoid any voltage back feed to the crossover when bypassed. A SPDT directing voltage to either the crossover input or the woofer input would have been simpler but I thought there might be a conductive path back through the HPF inductor. If not, then simpler is better but the switch as shown works. What would you recommend?

I wanted to try the Eminence 2-way crossover to roll in the HF driver earlier at 2.6 KHz to see what it sounds like. With this freq response it might be better to just use a 3.5 KHz high pass filter
like I did with the KL3012CX-8.

 

[5StringPocket]

Yep..That cab looked way over stuffed. I would try a thin skin of poly bat and see if that is enough. i think the last stuff I used was quilt stuffing from Wally World. Maybe .5 to.75 thick. 3m spray adhesive to tack it down.

My go to shown in the last cabinet photo is 1.5" acoustic foam with adhesive backing. It's about 1.4" at the peaks and .75" in the valleys. It has worked well for me for years and the pre-applied adhesive with peel off backing is so much more convenient than messing with adhesive spray. I have used polyfil for a sealed enclosure before but it was too loose so I wanted to see if mineral wool would hold it's shape better - too far the other direction.

 

[agedhorse]

Since the HPF's inductor is on parallel with the L-pad after the series cap, and there's no attempt at impedance correcting Zobel type networks (a good thing IMO) it's going to be simpler to just switch the + lead to the tweeter. Leave the L-pad fully up, doesn't matter.

I would suggest just using the HPF section with that woofer. By the time you get 30 degrees off axis there will be some rolloff of the 2.5-3kHz response already.