Accidental 2-way: JBL 2226 + Altec 902/Martinelli Horn

[tubino]

By the way, Rick's crossovers started with some criticism from me also!!!

Well, the truth is that mine started by trying to copy the layout used by spkrman57 when he built a pair for someone else! Except I was using larger coils on a slightly smaller board... so I had to do it differently... and yeah, Ron had some good ideas. And that's after pointing out my goofs.

I'm happy with the path lengths. Without getting the inductors closer together (= bad), the only way I see to make paths much shorter (while keeping input and outputs at the back and Lpad at the front) would be to rotate the L-pad 180 degrees and I don't think it's worth the hassle.

Ron S, it's been playing all day in the workshop, and sounding pretty good despite the new components. The much sharper roll-off on the 2226 is immediately noticeable when I turn off the horn. I'll go check on it tonight to see what's happening, but I was enjoying it quite a lot earlier today.

Ron C, I don't know how much is in yours, but this one is 3rd order and 3rd order with a zobel (cap and resistor) and EQ (cap and resistor) One reason I used so many of those little blue mini-strips is so that I could switch out caps later to compare Solen etc. I don't know if I'll do it, but I was thinking... I've got another pair of 2.7mH coils, pair of Lpads, and lots of resistors, term strips, and big oil caps. For the price of 4 more modest value aircoils I could replicate these BUT use all oil caps instead of polypro film. Maybe I would hate the sound, but it would be pretty easy to find out for sure. I'd probably build them as real working crossovers with a lot of space, and to make component switching easy, about 3 times as many barrier strips as spkrman would approve of.

 

[spkrman57]

doucanoe's is a 1st order 3-way with many less components than your crossover has.

He has a coil, 2 caps and a L-pad.

When I was in Vocational Electronics in HS back in the early 70's we built transistor AM radio with a whopping 5 transistors. We had a schematic on paper that was laid out on a piece of wood and brad nails where used for tie points. The components were placed directly on the paper schematic so it was easy to build.

That was a long time ago, but when I build crossovers I like to lay the components out like they would be in the schematic. After they were laid out and I saw what size board to mount everything all I have to do is properly orient the coils to avoid mutual inductance.

For me to build a crossover on a PC board would be more problematic than the way I do it.

I guess I'm just a stubborn old cuss stuck in my ways!!!! LOL!!!

Ron

 

[tubino]

I'm glad I had yours to look at. Those are the second or third ones I did (one doesn't really count), and while they don't look professional, there is something honest and good about them.

If you really did layout like a schematic, though, you'd have a ground bus, probably down the middle! Which wouldn't necessarily be bad... it would run from the L-pad to the neg input from the amp, with connections one side for HF and the other for LF...

That might actually make sense for a third or fourth order with inputs at one end and outputs at the other.

I was just in the workshop and spun a CD. The break-in is noticeable! I turned the l-pad from 10 o'clock to high noon. The sound is wider now too. Funny how that works. And this is with a POS old Pioneer receiver. I'm going to have to haul up at least a reworked console amp.

 

[spkrman57]

Crossovers I built for Brad

I'm not one for pretty, just functional.

Ron

 

[doucanoe]

Rick, I will be doing a similar x-over for my next 2-ways so it is nice to see how the both of you went about it. They will more than likely consist of 2226hpl in 4507 cabs with the 2380 horns and EV 2" drivers.


I'm sure Ohio Ron will be here every step of the way to encourage and harass

I don' know why motor run oils wouldn't sound good in a 3rd order crossover. I keep hearing that they are not ideal for higher orders but I guess you and I are somewhat alike. I gotta try it for myself first before I make a decision.

RC

 

[doucanoe]

I'm not one for pretty, just functional.

Ron

It doesn't count as one barrier strip if you use the biggest dang one ever made Ron


RC

 

[tubino]

It doesn't count as one barrier strip if you use the biggest dang one ever made Ron

Heh - I like that.

It always seems odd to me when people can build something based entirely on someone else's build, ordering the same parts etc. and have it turn out THE SAME. How can you build something without deciding to use some wood you have, or some porcelain sockets you have, or some transformers or rubber/cork feet you have, or recycle some chassis, or use wire you happen to have, some pilot lights or meters you happen to have...

It's because I never start with nothing, I guess, and I enjoy direct recycling. Surplus strips, two matching squares of stained pine that were cut off when shelves were shortened, random pair of plates that came with L-pads in a batch of surplus electronics I purchased, blue flexi-blocks from a local surplus guy... even when I try to copy someone else's design, it still winds up looking like something I would build.

I think this time next year I'll be finishing up some amplifiers I started a long time ago, but put on hold till I could build the workshop I just finished. I'll be working on the workshop (organizing all my parts in there!) and speaker projects for the next months, but then dive back into electronics and make my own transmitting tube amps. And being me, I'll wind up using 95% parts I already own in some combination I can't foresee yet.

I like that.

 

[doucanoe]

Heh - I like that.

It always seems odd to me when people can build something based entirely on someone else's build, ordering the same parts etc. and have it turn out THE SAME. How can you build something without deciding to use some wood you have, or some porcelain sockets you have, or some transformers or rubber/cork feet you have, or recycle some chassis, or use wire you happen to have, some pilot lights or meters you happen to have...

It's because I never start with nothing, I guess, and I enjoy direct recycling. Surplus strips, two matching squares of stained pine that were cut off when shelves were shortened, random pair of plates that came with L-pads in a batch of surplus electronics I purchased, blue flexi-blocks from a local surplus guy... even when I try to copy someone else's design, it still winds up looking like something I would build.

I think this time next year I'll be finishing up some amplifiers I started a long time ago, but put on hold till I could build the workshop I just finished. I'll be working on the workshop (organizing all my parts in there!) and speaker projects for the next months, but then dive back into electronics and make my own transmitting tube amps. And being me, I'll wind up using 95% parts I already own in some combination I can't foresee yet.

I like that.

Wood I have. It's the "other" I need to start stock piling but each new one requires different components I may or may not have more than likely. Other than the L-pads and inductors I got from PE, everything else came from my local electronics surplus place for my x-overs. Pretty much a hodge podge of the readily available.

Part of the fun of it for me is putting your own twist on things as long as it doesn't stand in the way of the physics and sound practice too much. Speakers are pretty much that way for me. My combinations of basement available drivers, enclosures and x-overs have worked out pretty well for the most part but have ruffled the feathers of a few purists and meter readers. Which by the way, is fun also

RC

 

[spkrman57]

Using what I had on hand

It doesn't count as one barrier strip if you use the biggest dang one ever made Ron


RC

I would rather have used 3 pairs of binding posts instead, but I needed them for another project.

I'm goint to try and cut down the big barrier strips to make several smaller ones for more convenience in the future.

I'm looking at building a similiar crossover in the future for a 2-way utilizing a JBL 2240H 18" driver in a 6 cu ft cab tuned to 40hz crossing over to a EV DH1A 2" compression driver on a short cast aluminum horn.

Due to the rising response of the 2240H, I plan a 3rd order LF at 500hz and a 3rd order HF at 800hz. My experience in the past says I should have a smooth blending, even with the split crossover frequencies.

Attenuation/EQ will be dealt with after hearing the basic system with L-pad to hear the basic system response and then I will determine how much EQ I want to use to suit to my liking.

Ron

 

[doucanoe]

I would rather have used 3 pairs of binding posts instead, but I needed them for another project.

I'm goint to try and cut down the big barrier strips to make several smaller ones for more convenience in the future.

I'm looking at building a similiar crossover in the future for a 2-way utilizing a JBL 2240H 18" driver in a 6 cu ft cab tuned to 40hz crossing over to a EV DH1A 2" compression driver on a short cast aluminum horn.

Due to the rising response of the 2240H, I plan a 3rd order LF at 500hz and a 3rd order HF at 800hz. My experience in the past says I should have a smooth blending, even with the split crossover frequencies.

Attenuation/EQ will be dealt with after hearing the basic system with L-pad to hear the basic system response and then I will determine how much EQ I want to use to suit to my liking.

Ron

I look forward to hearing what you think of those horns I sent your way. Did you ever get a handle on who made them?

RC

 

[tubino]

I'm looking at building a similiar crossover in the future for a 2-way utilizing a JBL 2240H 18" driver in a 6 cu ft cab tuned to 40hz crossing over to a EV DH1A 2" compression driver on a short cast aluminum horn.

What software do you use for modeling the woofer/cab? I just downloaded WinISD Pro last night and started monkeying with it. Seems okay, but I sure don't see how some people figure on getting 26hz out of a 2226... But it suggested that those ~200 liter boxes I got from you, Ron S., would work well for 2226!

 

[spkrman57]

26hz at how many db down?

What software do you use for modeling the woofer/cab? I just downloaded WinISD Pro last night and started monkeying with it. Seems okay, but I sure don't see how some people figure on getting 26hz out of a 2226... But it suggested that those ~200 liter boxes I got from you, Ron S., would work well for 2226!

Basically the 2226 works down to 45hz -3db and -10db at 35hz.

In the real world they often start rolling off gradually at around 60hz and much faster below 40hz.

I like them as most of my music tastes have very little below 40hz.

BTW Just thought I would post a pic of my quick prototype 2-way system:

JBL 2035HPL in 3 cu ft ported to 30hz(wrong tuning, but needed a box to break in the drivers for now), 1.6khz crossover to EV DH1A 2" compression driver on some unknown to me cast aluminum horn.

Ron

 

[Russellc]

To those who commented on adding HF compensation to the crossover for the horn, Rick put these together as a quick "throw together" system. He will build a more refined crossover for the future utilizing Wayne Parham's new and improved Pi 2-way crosover when time permits.

Ron

I hope he keeps us posted on that setup. It should really shine:yes:

russellc

 

[Russellc]

And in fact, that's what I did. I made two of these, and hooked them up.

The L-pads are quality units I picked up with nice metal wall plates. I was able to screw them right into a block of wood, and voila, I have them solidly mounted and easy to adjust. You can sorta see it in this BEFORE photo.

They work, too! Too cold to stay out in garage workshop for long, though.

Like the little bitty terminal blocks there! An alternative to "Zilch nuts" for on the fly crossover assembly.:yes:

Russellc

 

[Russellc]

Rick, I will be doing a similar x-over for my next 2-ways so it is nice to see how the both of you went about it. They will more than likely consist of 2226hpl in 4507 cabs with the 2380 horns and EV 2" drivers.


I'm sure Ohio Ron will be here every step of the way to encourage and harass

I don' know why motor run oils wouldn't sound good in a 3rd order crossover. I keep hearing that they are not ideal for higher orders but I guess you and I are somewhat alike. I gotta try it for myself first before I make a decision.

RC

Very interesting project. I also use the 4507 box, and have tried both 2225H, which is very similar to 2226H ( not sure the diff b/w 2226H and 2266hpl ), as well as 2235H and both worked great. I'm sure your driver will be excellent as well. The big JBL horn with big EV driver is very interesting. Keep all posted on this one.

Russellc

 

[doucanoe]

Very interesting project. I also use the 4507 box, and have tried both 2225H, which is very similar to 2226H ( not sure the diff b/w 2226H and 2266hpl ), as well as 2235H and both worked great. I'm sure your driver will be excellent as well. The big JBL horn with big EV driver is very interesting. Keep all posted on this one.

Russellc

The specifications are the same for the 2226H and 2226HPL other than the private label (_PL) designation from what I understand. I do also have a pair of the EV HP940 horns that were originally used with the EV DH1A's so that might be the route to go. The JBL 2380 horn is just a little smaller and cosmetically appealing to me.

I can just hear Ron (ohio) now after reading that though. "There you go again, Being more concerned about being pretty before you even know if it works... "



I hope to be able to use it as a 2-way with the higher potential HF extension of the DH1A with compensation but we shall see I guess.

RC

 

[tubino]

Last night I hauled a Dyna SCA-35 and variac up to the workshop and hooked it up instead of the filthy old Pioneer receiver. The variac decided not to work (???) and I was impatient, so even though I hadn't played it in almost a year, I plugged her in and let her rip.

(Years ago I replaced the coupling caps (Vit Q) and the first filter cap, and replaced the 60 ohm resistor in the CRC with a 1.5 or 2H choke to make it CLC. Replaced the cheap nasty diodes with 1200v 6A hexfreds.)

It worked, but I had to shut down (family commitments) and come back later when everythign was really cold. Sound was just okay at first, but after ~20 minutes it started to open up. By 30 minutes it was definitely sounding better than the Pioneer in every way. One thing that was striking was how much more visceral the bass had become by switching from a 20 watt SS unit to a 20-watt tube unit.

Started layout for a version of the crossover using big oil caps, just for the hell of it.

 

[spkrman57]

Tube amps always sound better to me, but just my opinion.

The higher efficiency the speakers, the better a tube amp sounds to me at least. With SS, I find lower efficiency works better if you have big watts!

Off Topic: On my quick 2-way, I pulled out one of the ports leaving a 3" dia hole at 3/4" and plugged the other port. The tuning raised up plays much better. I do have to say that while the JBL 2035 is a bargain compared with the 2226, the 2226 is much better with the detail and such.

Ron

 

[tubino]

A little update: today I got one B&C DE250 driver (the second is coming in a week or so...), and hooked it to an Edgar 650 hz tractrix horn. I replaced the Altec/Martinelli with this on one side.

Initial impressions are very favorable! The soundstage/dispersion are quite different between these two horns, and it's kinda weird to be listening to music with one of each, but I flipped the signal to mono and alternated between them a little.

I didn't think I would wind up using the workshop so much as a place to experiment with speakers and crossovers, but I can see now there will be a LOT of that. I'm going to have to come up with a decent single-ended amp to use out there...

 

[tubino]

Surprise! The second B&C DE250 came today, along with PE parts, so I am able to hook up the B&C's to 1) the Martinellis, or 2) Edgar 650hz tractrix, or 3) to Selenium adaptors and the $9.90 JBL CD waveguide used in the Econowave Guide project. I think I'll make the stock EWG crossovers and go from there, but I'll be listening to the Martinellis while I make them.