Zilch's AK Design Collaborative - Econowave Speaker

[westend]

Hi Spec. right after I found those, I found a pair of ESS AMT 1c. I bought them just for the big Heil tweeters for my main system, then looked at the bass cabs and thought, what the hell and made eWaves out of them. At that point I put the 4500 in a closet and just now remembered I had them. I have a TT and three amps in the cue before I get to the 4500 eWave project. I HAVE to get some of these half done project off the bench. The 5000 have MUCH better woofers and think they would make great eWaves. both of them have great bass that crosses much higher than the eWave project calls for. Good luck.

Temporary hijack in operation/

Dennis, I'm going to be breaking out the Heils for an upcoming speaker project. Did you find a crossover point you liked with the Heils? I'll be using Altec 802 on 811 horn and using the Heil AMT1's for the top end.

Hijack ended\

 

[Russellc]

Good thought, but isn't pro stuff usually BIG? Recall I have a small listening/home theater/computer/hobby room, and was thinking 12" wide econowaves.

While people have done all sizes of woofers here, myself, I wouldnt bother with anything smaller than 12 inches. That's just my own take, and may not be your thing. I like the High efficiency slam of the larger (Pro) stuff. It is a little larger, 4507 cabs are 5 cu ft, large, but much smaller than the Altec A7s on the other system. Wayne over on The Pi forum uses 15 inch woofers and aligns them in a box around 3 cu ft with excellent results. He shares plans and you can download programs there too. LOTS of excellent reading, Wayne's diatribes about crossovers, horns and waveguides and everything to do with them and their interaction with each other, are all a must read! these systems are very similar to E'wave here
and could be combined with it as well for a reasonable size package with large slammin pro type drivers.

On the other hand, several members have had excellent results with every thing from AR to Bose. You might also want to read up on these same guy's use of the smaller square wave guide that is "E'wave certified." Its square in shape and while many here have used a lot of them, I dont know a thing about it, other than it can work!

Russellc

 

[Russellc]

Temporary hijack in operation/

Dennis, I'm going to be breaking out the Heils for an upcoming speaker project. Did you find a crossover point you liked with the Heils? I'll be using Altec 802 on 811 horn and using the Heil AMT1's for the top end.

Hijack ended\

High jack temporarely re-opened: Interesting. I bet I know what you're going to drive those with! Snag a pair of these cheap guides for later use (If they ever get out of backorder status).....Cheap fun I tell ya!

High Jack transitioned to normal E'wave status....nothing further to report


Russellc

 

[Russellc]

Lest anyone be discouraged, I'll reiterate that both of these combinations sound very good as-is. As Skywave observed, we're giving this waveguide a higher level of scrutiny in system optimization, is all.... :thmbsp:

I checked the first page to make sure, but figured it would be way too early to have links to the new crossovers. I guess there is a version derived from the original E'wave crossover, and also a LR crossover. I've seen some examples of these that Jack and You have worked on, but was wondering if you could post up the latest versions....understanding of course that nothing is finalized and so forth. I recall a version of the LR being posted, I don't recall seeing the original version tweek posted. I think I read a description below a frequency response chart post including some parts changes? I've got lots of parts laying around to wire nut together.

Thanks,

russellc

 

[Russellc]

Yes, yet today, maybe, though I'm having some difficulty keeping promises here of late....

This sim of another project from the Zaph website illustrates what I believe we may have going on:

I am working with some suggestions from NHT's Jack Hidley and "The one who knows." I have been able to move the forward axis down a bit by making the eWave highpass third-order per Wayne's design, and am next working on the lowpass. The Rane tech note suggests that a classic symmetrical third-order Butterworth's -15° downward tilt may be useful, Fig. 1a:

"Cancellation Axis" = forward null, for those following what's going on with these design adjustments; the view is from the side, showing the vertical pattern.... :thmbsp:

Wow! What kind of super equipment is required to get those vertical baffel showing the lobes and null points? That's really cool if its an actual measurement, which it appears to be? ( From the Zaph speaker )

Who's "The one who knows" ?

Russellc

 

[Russellc]

I have been able to move the forward axis down a bit by making the eWave highpass third-order per Wayne's design, and am next working on the lowpass. The Rane tech note suggests that a classic symmetrical third-order Butterworth's -15° downward tilt may be useful, Fig. 1a:

I figured he was on to something with that 3rd order HP, his measurements are pretty flat on his 4 PI, which is very similar to the larger E'wave here and as you know, uses that driver. Bravo to you and Jack for going the extra mile once again, to flesh out this great combo.:thmbsp::thmbsp::thmbsp:

Russellc

 

[Spectrum77]

...The 5000 have MUCH better woofers and think they would make great eWaves. both of them have great bass that crosses much higher than the eWave project calls for. Good luck.

Thank you, Dennis. For $30 I might just pick them up- if not for me, for enlightening a mate.
Occasionally let the KPM (HPM-100) E/W out for a run around the yard, but I forsee the 15" 2226H reigning as The Supreme Overlord here for quite some time yet...

 

[Guest158]

After hearing some VOTTs recently I want horns in the house! I've read maybe 1/4 of the posts on this thread I guess now is the time to ask questions.Alot of the tech & measurements are beyond my grasp. With that being said, can average Robert competently assemble the crossover? I have the schematic & parts list for the higher eff. woofers-Altec Model 14(96.? eff.) Doesnt "look" to tough if I can get some practice soldering? .Cabinets are Madrids modded with the tweeter moved above the Model 14 woof.My thought plan is to flip the baffle & grill so woof is near top,dont want to mod as grill is made like a baffle & I like.Will add a port tube of sorts where tweet was.Will build a box same width & depth as cabinet to get Model 14 or 19 look.Now comes the crazy part,thinking of using the Selenium 220ti with the Pyle Pro PH612 s big brother the PH818 7.6 x 17.6 x 6.9.I think it would at least look impressive, not looking for sound prefection like the pro's here. This project wont take place until after holidays so plenty time to prepare.
Thanks for any input, Robert

 

[Spectrum77]

...thinking of using the Selenium 220ti with the Pyle Pro PH612 s big brother the PH818 7.6 x 17.6 x 6.9.I think it would at least look impressive, not looking for sound p(er)fection

From one novice speaker builder to another- if you want to experience what the Econowave project can offer, stick with the standard waveguide and X/O that's been tested. You'll not be dissapointed and won't be second guessing your decision to deviate from the standard waveguide. (I'm speaking from experience of having tried alternatives...) It's a really easy job, even for first timers!

 

[Zilch]

With that being said, can average Robert competently assemble the crossover? I have the schematic & parts list for the higher eff. woofers-Altec Model 14(96.? eff.) Doesnt "look" to tough if I can get some practice soldering?

AKer Wiredbecker shows you here:

http://www.youtube.com/watch?v=lw7pTwpx0K0

 

[Guest158]

Thanks for the info guys! Great video!

 

[Zilch]

Bose 301 MiniWave:

So what did he think of them and was there any testing involved???

Quick and dirty, not on the test stand, even:

460149/8410=54.7145​

 

[Zilch]

Is it a null or the forward axis?

Back to DE250 and DC300 in the PE Trap box, still with the ZilchNutted kludge 3-pole eWave crossover, trying to ascertain if I'm on the forward axis or in a primary null:

With the HF driver inverse polarity, minimum phase measured at what I believe to be the forward axis, 6" above the waveguide center:

With the HF driver in positive polarity, minimum phase measured at what I believe to be the lower null, 12" below the waveguide center:

Just the nulls, inverse at forward axis only:

Notes:

1) With inverse polarity, the null is ~0 Degrees phase at 1.7 kHz.

2) We can clearly see the vertical directivity of both the woofer and waveguide over the measured span of +/- 12" (+/- 15.26°) from the waveguide axis.

3) "Zilch Effect" is in evidence: the lower null occurs above the on-axis crossover frequency, and vice-versa.

4) Forward axis is 6" (+7.77°) above waveguide center at 44" mic distance from baffle, upper null +24" (+28.6°), and lower null -18" (-22.25°) from there. The forward lobe is 50.85° tall, and somewhat asymmetric. The upper null is outside the waveguide (and woofer) vertical pattern.

 

[Bauhausler]

3) "Zilch Effect" is in evidence: the lower null occurs above the on-axis crossover frequency.

If my squinting and head scratching are correct this means that the virtual acoustic centers of the drivers are slightly closer together when measured at the lower null than they are when measured on-axis.
Since the null occurs when the path length difference is 1/2 wavelength, then a higher frequency of occurrence (shorter wavelength) means the path length difference is less, as it would be if the drivers were moved closer together.
Not knowing how to interpret the acoustic center of a woofer whose dustcap appears to be about about 1/2 of the wavelength at the xo freq (lambda =8") I have no answer for this.
I wonder if changing to a smaller dustcap, or removing it and installing a phase plug, would make a difference.

 

[Bauhausler]

Stopped by Bauhausler's today and saw another set of big Advent eWaves in the works. Looking forward to seeing the progress.

Luckily someone else is restoring the NLA cabs for that pair.
I hate wood work.

LA Ewave set #4 is already in the works. I plan to put DE250s and QSC WGs into a pair of ULA cabs. The QSC WGs should arrive in a week or 2. Woofers are ready to drop in. They'll get external XOs for tweakability.
It's a good fit mechanically and I already know everything I need to about these cabs & woofers. The WGs will be surface mounted on the cab rim at the sides and have filler strips under the upper and lower edges, moving the waveguide front surface about 1.125" forward of the baffle. That pair may get some internal damping and bracing to reduce resonance.

Otherwise the whole project would be just too easy...

 

[Zilch]

Since the null occurs when the path length difference is 1/2 wavelength, then a higher frequency of occurrence (shorter wavelength) means the path length difference is less, as it would be if the drivers were moved closer together.

Dunno. When it happened before over on DIY audio several months ago, I gave it a name for the sake of legitimacy, claiming it had something to do with harmonic convergence.

[I doubt it warrants a Nobel Prize... :tongue: ]

 

[skywave-rider]

Back to DE250 and DC300 in the PE Trap box, still with the ZilchNutted kludge 3-pole eWave crossover, trying to ascertain if I'm on the forward axis or in a primary null:....

If you are looking at the acoustic forward axis, shouldn't you should see the waveguide lose pattern control and increase in response around crossover frequency as you explore the edges? I think it's unlikely the nulls are exactly at the edge of the vertical pattern. But I don't see any response bulge.

 

[donprice]

Can average Robert competently assemble the crossover? I have the schematic & parts list for the higher eff. woofers-Altec Model 14(96.? eff.) Doesnt "look" to tough if I can get some practice soldering?

Get the circuit boards for the crossover from Zilch. The instructions are easy to follow and you will get a very professional looking crossover when you are done. Real easy and real pretty.:thmbsp:

Order your parts now since Parts Express seems to have a hard time keeping the eWave components in stock.

 

[ROSSO]

Thanks for the info guys! Great video!

Why not just make new baffles? E-waved Madrids: View attachment 151990

 

[Zilch]

If you are looking at the acoustic forward axis, shouldn't you should see the waveguide lose pattern control and increase in response around crossover frequency as you explore the edges? I think it's unlikely the nulls are exactly at the edge of the vertical pattern. But I don't see any response bulge.

The response is remarkably stable within +/- 15° of the forward axis. From the yellow curve in the nulls plot, the upper null is clearly outside the pattern of both sources at this frequency. Occuring at 34.3° (arctan 30/44) above the waveguide axis, that makes sense; I believe it was you who first observed this.... :thmbsp: