Zilch's AK Design Collaborative - Econowave Speaker

[Vaughn]

first time post...

Hello all!

I recently picked up a pair of Altec Valencias at a local thrift store for $65, which I immediately fell in love with when I got them home and hooked them up to my Jolida 102b(now sold to fund a 2A3 diy project).

I have been an audiodork for 20+ years but this was definitely a pivotal moment for me, like when I bought a pair of Heathkit w5m's from an old gentleman for $30 and heard good tube equipment for the first time.

Anyway, I am now a "dyed in the wool" horn (waveguide?) guy. I have been
following this thread with much interest and have begun the slow(as my budget will allow) acquisition of the parts necessary to construct my own econowave. I just bought a JBL LE14a(just one so far!) and would like to
start designing my own cabinet for it. I have done some searches and found a couple of box size and vent dimensions I would like to run past you guys for your opinions; I found one(posted by Zilch) which describes a sort of
generic box good for the LE14xx series which is 3.38 cu ft with a 4" diameter port 8" long. Another I found was 3.4 cu ft with a 3" diameter port 4" long(tuned to 35HZ). Do either(or both) of these sound like good boxes/vents for this woofer or does anyone have a better suggestion.

Another question regarding box design; would it be advantageous to design in a step to the cabinet to time align the HF driver and the LE14A? I will initially be using a low power 2A3 amp to drive these but I suspect that I will be biamping later on and I know some of these processors allow some adjustment for time alignment.

Thanks for your help!

 

[Russellc]

Russel, those are very cool looking cabs, I could see those on top of my ESS ewaves. For all the others that got boxes today.....times'a wastin'. You will be greatly rewarded. Make sure to post good pics so the Zman can include you in the Who's built them so far link. Cheers.

I've already been put in that list, I'm to stupid to provide a link, but if you go to member projects, I think I was number four or so. There are other pictures of this system throughout the thread. Or do you mean the "Indignia thread" list? I'm not in that list yet. Soon though, soon!

As to the PE black curved cabs, they are for my indignia project....I'll have to use them with that project. But another set wouldnt be the end of the world, I'm sure PE has lots. I would need to come up with some "Cradle" contraption
to mount them and so forth.

They really are a well made piece for the money. Very nice fit and finish. The gloss black finish mine came in is very glossy and extremely well applied.

Russellc

 

[Russellc]

COOL!

Now that my letter is off to Santa, let's think a bit about integral crossover mounting options:

1) None: Just the driver in the box, with the leads brought out to the two terminals on the rear; crossover is external, or in the LF module.

2) Integral: The standard crossiver mounted inside, with a second set of terminals for the woofer output, and the L-pad, all on the rear, though bottom, recessed, would work too, probably.

3) Biamp: Three pair of terminals -- HF input, LF input, and woofer output. Inputs may be jumpered for single amp operation. A DPDTswitches to the high-efficiency comp filter, if desired.

4) Active Biamp: Woofer connects separately; there's more design work to do for this option....

Any thoughts?

The "Active Bi amp option" would involve the CX 3400? Or a DIY cross over for the low frequency leg of the crossover? The CX 3400 on the other hand has already been used in this thread. And its fairly inexpensive, maybe cheaper than simple DIY?

The "Bi Amp Option" also looks interesting, with lots of flexibility as well.


Russellc

 

[GordonW]

I also contend that, contrary to prevailing opinion, the OLA (Masonite) and NLA (steel-frame) woofers are NOT equivalent. Refoam a pair of the originals and see if that is not so, maybe.

They have the same cone and the same voice coil, with the same strength magnet. I've had them all apart and compared.

Unless there's diffraction differences (possible), then there should be no significant difference. And if there is diffraction issues, the newer ones should be superior (no "step")...

Regards,
Gordon.

 

[packrat]

got the JBL L55s....

Got the L55s on the weekend - cabinets are nicer than I was hoping for, so cutting the baffles up might be out of the question. I ordered surrounds from R Cobb. Both dustcaps are pushed in (how, why??) but I think I will cut the caps out when refoaming these and try to push them back out that way. The vacuum trick did not work. As well, both woofers measure between 6 and 7 ohms, but not from the push on connectors! One measures about 10 ohms at the push-on, the other 8 - but both measure ~6.5 ohms at the tinsel leads! I need to clean that connection some how. Anyone else with old JBL woofers notice this problem?

To try the EcoWg out I can flip the L55s upside down (getting the LE14 up close to the horn), remove the beat up base and mount the horn on top, maybe in its own box but at least on a baffle, which I think it'll need. I think I have most of the crossover parts already from parted out speakers, except for some caps. Series 2 HPM 60s use a nice big 1.5 mH choke and have nice L-pads :thmbsp:.

....
Being in Canada poses an extra limitation on component selection. The JBL waveguide which sells for $9.60 from the distributor turns around for $30 at the dealer. The Pyle version is not available here at all, but ordering them from MCM works out close to $20 each.
...........

MartinQ, I'm in the same boat - up in Canada. What is the part number for the Pyle Pro horn at MCM? (53-970?). I'm going to order the drivers from Parts Express - are there any horns at PE that will work for this? Was $30 at a walk-in JBL pro service center/dealer? I'd go for that if they had them.

 

[Russellc]

Yep been reading it. :thmbsp:

Wish the low bass was a bit better, but as Zilch has said many times that is the
tradeoff with this efficiency, still wondering if there may be better woofer option.

What is interesting is my first thoughts before even reading anything was to take
the drivers out of those boxes and build a piramid shape, line up the drivers mirror.

But nothing will happen till after winter that is for sure around here, so for now its
play with what is there, see if there are any improvements an just use um.

Anyone have any thoughts on the tweets, how do they compare to others, can I
try them in my waves?

In terms of alternative woofers, I can firmly endorse the JBL 2235H. 2225H worked pretty dam good as well, just not as much bass.

Russellc

 

[Zilch]

JEEZ, E'Wave is HOT this morning!

Now I am wondering where to get adapters to run LE85 with the PT 1 3/8" threaded horns..?

I didn't get to checking out the LE85s this weekend, but I spotted them here; just need to rearrange some stuff to get to them. We're building prototype Indignia boards tonight, so it may not happen today.

The Selenium throat adapters from PE are fine:

http://www.parts-express.com/pe/pshowdetl.cfm?Partnumber=264-323

I just bought a JBL LE14a(just one so far!) and would like to start designing my own cabinet for it. I have done some searches and found a couple of box size and vent dimensions I would like to run past you guys for your opinions; I found one(posted by Zilch) which describes a sort of generic box good for the LE14xx series which is 3.38 cu ft with a 4" diameter port 8" long. Another I found was 3.4 cu ft with a 3" diameter port 4" long(tuned to 35HZ). Do either(or both) of these sound like good boxes/vents for this woofer or does anyone have a better suggestion.

I tune them to 30 Hz for an "extended bass" alignment. 35 Hz is more of a "high fidelity" option. Your choice. The smaller the diameter of the vent, the higher the vent velocity and the greater the likelihood of "chuffing" at higher SPLs. We're using dual 2" in Wiredbecker's C36s, 4.25" long. If there's a chuffing problem with that, we'll move to four longer ones.

Another question regarding box design; would it be advantageous to design in a step to the cabinet to time align the HF driver and the LE14A? I will initially be using a low power 2A3 amp to drive these but I suspect that I will be biamping later on and I know some of these processors allow some adjustment for time alignment.

Flat baffle is fine. Dial in the requisite delay once you have the ability to do that. I don't know what that would be, which is part of the problem; each combination must be measured to locate the acoustic centers.

As to the PE black curved cabs, they are for my indignia project....I'll have to use them with that project. But another set wouldnt be the end of the world, I'm sure PE has lots. I would need to come up with some "Cradle" contraption to mount them and so forth.

Santa's bringing me the 0.5 cuft ones, because I saw a conflict between the corners and the baffle mounting bolts in your pics. I'll report once he delivers.

The "Active Bi amp option" would involve the CX 3400?

Yes. Jack worked out how to do it using the standard E'Wave highpass and comp filter earlier in this thread.

They have the same cone and the same voice coil, with the same strength magnet. I've had them all apart and compared.

Unless there's diffraction differences (possible), then there should be no significant difference. And if there is diffraction issues, the newer ones should be superior (no "step")....

My contention derives from the fact that the lowpass filters are very different in NLA vs. OLA, which may relate to different tweeters, as well. It's easily evaluated in OLA cabs, which will accept both versions.

To try the EcoWg out I can flip the L55s upside down (getting the LE14 up close to the horn), remove the beat up base and mount the horn on top, maybe in its own box but at least on a baffle, which I think it'll need.

No baffle required, it would seem. Watch for what I do with the stock PE cabs for the waveguides here.

My standard LE14 test boxes are upside-down L55s. It was a bitch stripping the original foot off, as it was attached with machine wire staples. I ended up cutting them with nail nippers.

Measure the tuning with the stock port and "shrink" it as required.... :yes:

 

[Bauhausler]

Update on ULA EWave tuning

This morning I took the drivers out of my Utility Large Advent EWaves to make a slight crossover adjustment*. I took the opportunity to add some more stuffing to the boxes. I had a little under 2 lbs of heavy pink fiberglass in there originally. They sounded under-damped some of the time, and anywhere near a room boundary the bass level boomed way out of control. While I had them open I added about 3/4 lb of Dacron material that I had taken out of a B139 transmission line. The cabinets are still not 'packed' but are fully stuffed. I now have them experimentally 14" off the floor on tilted stands and about a foot from the back wall. The bass balance seems about right in this initial listening. I'll have to listen to more recordings before I decide that this is the final recommendation but I'm leaning toward a pretty heavy fill for these Advent cabinets.
At Dennis's house on Saturday they were overwhelmingly boomy when back against the wall and that's just not right.
Eventually I'll try them on 24" level 'stands**' and flat against the back wall. If that works, I'm done with the box tweaking.

<UPDATE>

I placed them against the back wall raised up quite high. The horn center is now at ear height: 48" up, putting the woofer center about 38". This is good positioning for this room because of unavoidable obstacles. I'm running the lpad of the horn backed off about 45 degrees. The back wall now gives just enough reinforcement to support some 'socko' in the midbass. Man, the ease and openness of this horn is outstanding. It's hard to imagine someone not liking the mids and treble from this system.






* polarity
** Marantz HD-77 cabinets

 

[jandg]

K, i just got off the phone with JBL & ordered the 338800-001 PT's & came to a woppin $ 27.28 & shipped out today. I am also eyeballing another Ashely active XO, 2001 maybe..? I had a 4001 before & liked it. Has anyone done E-wave with a Ashley yet..? I will be usieng my SR4725's w/ 2226H & just disconnecting the internal passive XO & also the 2426H cd. I might try the 2426H on the PT, but will order the CD used in regualr E-wave, I would like to go active because I want to play with other set ups with the sr4725 cabs etc down the road. I can easily build the passive high eff version of XO but really looking to go active. I plenty of tube amps, PP SET SEP etc, etc, so that is covered. SS are dime a dozen if needed on bottom end. MY PP amps should do well for the 20x20 room this is in. It will be curiouse to A/B agaist the stock sr4725 with 2226H 2426H & 2370 horn which on it's own is surprisinglly very nice with 45 SET etc,..The Ashley active 001 series XO's are everywhere for good prices. I think I will go 2001 this time instead of 4001. Should be fun & will report back. To bad the 2426H driver is not sutible for this E-Wave gig as it to me is a superb driver. smooth & very good.
J & G.

 

[wiredbecker]

We're building prototype Indignia boards tonight, so it may not happen today.

Uhhh my car is 'in the shop'. Might have to do the build tomorrow night if I can't get the new coils installed this evening if indeed that is the problem. I'm bummed! I want to get wrenching on speakers not cars!

 

[Zilch]

To bad the 2426H driver is not sutible for this E-Wave gig as it to me is a superb driver. smooth & very good.
J & G.

It IS suitable, of course, but somebody's gotta work out the HF comp for it. Sorry, not me right now; I'm working with vintage LE85s. :yes:

I placed them against the back wall raised up quite high. The horn center is now at ear height: 48" up, putting the woofer center about 38". This is good positioning for this room because of unavoidable obstacles. I'm running the lpad of the horn backed off about 45 degrees. The back wall now gives just enough reinforcement to support some 'socko' in the midbass. Man, the ease and openness of this horn is outstanding. It's hard to imagine someone not liking the mids and treble from this system.

If not "Keepers," it sounds as if these are at least approaching "Benchmark" status in your collection, and you've rolled through just about every speaker known to man there.

E'Wave is just plain silly good.... :thmbsp:

 

[Vaughn]

I tune them to 30 Hz for an "extended bass" alignment. 35 Hz is more of a "high fidelity" option. Your choice. The smaller the diameter of the vent, the higher the vent velocity and the greater the likelihood of "chuffing" at higher SPLs. We're using dual 2" in Wiredbecker's C36s, 4.25" long. If there's a chuffing problem with that, we'll move to four longer ones.

Thanks Zilch, is that a 3.4 cu ft cabinet on the C36s?

 

[mrTT]

Wow! This post is keep on growing. It has become a legendary post for sure. Outstanding!

 

[SPAM]

The Center channel drivers will become a JBL LE111H and an EconoWave using the six inch square waveguide.

Please do share your results, especially if you decide to tweak the low-pass filter from its default values.

 

[Bauhausler]

It IS suitable, of course, but somebody's gotta work out the HF comp for it. Sorry, not me right now; I'm working with vintage LE85s. :yes:

If not "Keepers," it sounds as if these are at least approaching "Benchmark" status in your collection, and you've rolled through just about every speaker known to man there.

E'Wave is just plain silly good.... :thmbsp:

Agreed on 'silly good'. I'm sitting here listening to my modded Audiophile Grade Sony SCPH-1001 PS-1 as a CD player, obsolete Yamaha C-2X preamp and intellectual property violating Rowland copy MOSFET amp with the ULA Ewaves and it's just absurd how good this sounds for how cheap/simple/easy it all is.

It almost makes me want to do a 'cost no object' version with JBL woofers, fancy cabinetry, expensive compression drivers and snake oil crossover parts but that conflicts with the spirit of the EWave project to produce high sound quality/dollar.

I do still have a few more famous speakers to make my way through. I've never owned DQ-10s (!?!1) so I'm working on getting a couple of pairs of those to renovate and fool with. There will be an interesting tale to tell if this deal goes through.

Also I"ve never had Quads here so I'm going to renovate a pair for a friend this Spring. Reportedly these will come with all of the original 1960s Quad tube electronics, as purchased by the friend's deceased father. That will be a lot of fun/work.

 

[dnewma04]

Skip the JBL woofers, jump up to Lambda's.

Nothing wrong with taking the econo out of these waveguides and doing something special with them.

 

[Zilch]

Thanks Zilch, is that a 3.4 cu ft cabinet on the C36s?

http://www.lansingheritage.org/images/jbl/plans/c35-c39/page2.jpg

It almost makes me want to do a 'cost no object' version with JBL woofers, fancy cabinetry, expensive compression drivers and snake oil crossover parts but that conflicts with the spirit of the EWave project to produce high sound quality/dollar.

There are plenty more 1" drivers to try with the $9.90 E'Waveguide; the big jump is to the "real" 1.5" PT-F95HF w/BMS 4555, a $500 combo. Wish they made a Nd version of that driver.... :yes:

 

[jaybird]

Is there a waveguide that would work well with my Altec 299-16a drivers?
Been trying to post pics of pc boards I'm making the "old school way" with the bad chemicals and cabinet options I have but can't seem to figure this dam computer stuff out!

 

[Zilch]

Is there a waveguide that would work well with my Altec 299-16a drivers?

1.4" exit?

Not from JBL, no, alas. ity:

You could fab a short throat adapter to 1.5", but I couldn't guess what angle to use. Dave'll know, maybe.... :yes:

 

[dnewma04]

If you don't mind the more limited coverage angle of the 18sound XT1464, it's a more than viable option to look into. Measurements look impressive with their 1.4" drivers, not sure how the Altec would compare.

I don't have any experience with the XR1464, but it's probably more up to the task of holding something as heavy as a 299-16A. (not that the XT is underbuilt, for plastic, it's remarkably heavy duty).