Zilch's AK Design Collaborative - Econowave Speaker

nerdorama · Dec 11, 2008

Hi Skywave,

The aluminum cans are GE 97F5705, 5uF motor runs. I'm going to use them for the 4.7uF HF cap as a starter since I already have them. The white round caps are 10uF PP from BG Micro which I will parallel with some 2.2uF Daytons for the woofer caps.
http://www.bgmicro.com/index.asp?PageAction=VIEWPROD&ProdID=11511

Hopefully I'll be able to post again this weekend with pictures and some preliminary listening opinion. I'm going to start with some EV SP12B's for woofers but I also have some original Advents that I can press into duty if needed.

Regards,
John

skywave-rider · Dec 11, 2008

Nice!

Zilch · Dec 12, 2008

Russellc said:
The center brace will have to go. ( At least with this driver. The Selenium is flatter. ) It does fit the front opening. One more pic og the W'guide face down on the front baffle.

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 crossover 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?

djnagle · Dec 12, 2008

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.

nerdorama · Dec 13, 2008

OK, they're working

Preliminary report:
The woofers are EV SP12B's. Boxes are too small, but I stuffed them full of damping material and plugged the slot port. The best info I could find indicated about 94-95dB sensitivity, so I built the <95dB crossover version. Not enough high end so I converted to the >95 version and have the Lpads at about 50% rotation. Used Zilchnuts and solder to patch the xover together.

Sounding pretty good so far after about 4 hours run time. Kind of harsh and lifeless for the first few minutes. I think I will need to do some measuring tomorrow and tweaking. Maybe a zobel on the woofer to flatten the system impedance a trifle. Good dynamics compared to my direct radiator speakers, Lynn Olson ME2's, but the ME2's sound more refined.

Running them with my DIY tube amps, ~ 6-8 watts.

So far, so good. Will report more as news breaks.

Regards,
John.

Zilch · Dec 13, 2008

Excellent!

I've added you to the Official E'Waver List.

http://audiokarma.org/forums/showthread.php?p=2260584#post2260584

Seems the woofer may not be running optimally in that alignment. I know zip about SP12B; maybe Gordon or somebody who knows will chime in.

Those are handsome cabs. I'd want to find a woofer that'll work well in them. :yes:

Suggestion: crank the L-pad all the way down to hear how the woofer sounds playing alone. It may be necessary to tweak the lowpass; measurements will tell what's going on.... :thmbsp:

packrat · Dec 13, 2008

Selenium D210Ti ?

This driver is about $15 less expensive - I saw some earlier posts where it was found to be close to the 220 - has anyone here tried this driver out? Not worth the savings?

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=264-235

jackgiff · Dec 13, 2008

packrat said:
This driver is about $15 less expensive - I saw some earlier posts where it was found to be close to the 220 - has anyone here tried this driver out? Not worth the savings?

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=264-235

Although I have several pairs of D220Tis on hand for the projects that are in the mill, I just ordered 6 each of the D210Ti's from PE. Can't hurt to have a few spares. And it looks like they might be going away, since they are not in PE's new catalog, according to some folks here.

The D220Ti is perhaps the tiniest bit smoother. But you need to listen close to hear the difference. For all practical purposes, they are interchangeable.

Pio1980 · Dec 13, 2008

Zilch said:
Excellent!

I've added you to the Official E'Waver List.

http://audiokarma.org/forums/showthread.php?p=2260584#post2260584

Seems the woofer may not be running optimally in that alignment. I know zip about SP12B; maybe Gordon or somebody who knows will chime in.

Those are handsome cabs. I'd want to find a woofer that'll work well in them. :yes:

Suggestion: crank the L-pad all the way down to hear how the woofer sounds playing alone. It may be necessary to tweak the lowpass; measurements will tell what's going on.... :thmbsp:

I finally got lucky with a websearch and I am pleased to be able to contribute something for a change.
Master list of E-V vintage engineering data sheets;
http://archives.telex.com/archives/EV/Speakers/EDS/

SP12B:
http://archives.telex.com/archives/EV/Speakers/EDS/SP12 & SP12B EDS.pdf

Theil-Small parameters:
http://www.geocities.com/tadgesualdo/12trxbTSparameters.html

Trust this will help.
S.B.

Zilch · Dec 13, 2008

Pio1980 said:
I finally got lucky with a websearch and I am pleased to be able to contribute something for a change.
Master list of E-V vintage engineering data sheets;
http://archives.telex.com/archives/EV/Speakers/EDS/

Thank you for posting the links, S.B. It's a 16-Ohm driver, looks like, and accordingly may require adjustments to the lowpass filter.... :yes:

nerdorama · Dec 13, 2008

There are different versions of SP12B and mine say 8 ohms on the labels. Mine are newer than those shown in the links and have a different frame. This picture is similar to mine.

Zilch · Dec 13, 2008

nerdorama said:
There are different versions of SP12B and mine say 8 ohms on the labels. Mine are newer than those shown in the links and have a different frame. This picture is similar to mine.

Measure the voice coil DCR. If it's in the range of 5 - 6 Ohms, they're 8 Ohms nominal.

For a time, JBL played fast and loose with the impedance stated on foilcals. LE14A, for example, may say either 8 or 16 Ohms, but all have the same 8-Ohm voice coil; it's not even as if they're somewhere in-between.... :yes:

Pio1980 · Dec 13, 2008

nerdorama said:
There are different versions of SP12B and mine say 8 ohms on the labels. Mine are newer than those shown in the links and have a different frame. This picture is similar to mine.

I'm no expert on much of anything but did dig out some info for a lone orphaned SP-8C last week, your's look more like 'C'. If they have the treated fabric corrugated surrounds with whizzer cone along with cast frames I'd probably look at handling them as the later versions, here;
http://archives.telex.com/archives/EV/Speakers/EDS/SP8C, 12C, 15A EDS.pdf
S.B.

GordonW · Dec 13, 2008

Zilch said:
Measure the voice coil DCR. If it's in the range of 5 - 6 Ohms, they're 8 Ohms nominal.

For a time, JBL played fast and loose with the impedance stated on foilcals. LE14A, for example, may say either 8 or 16 Ohms, but all have the same 8-Ohm voice coil; it's not even as if they're somewhere in-between.... :yes:

Apparently, the same is true of early LE10s. Got one here, that says "16 ohms" on the tag... DC resistance is 5.2 ohms. Right in spec for an 8 ohm model. Fortunately, that made it easy for me to match a cone kit that I had saved, to fix the other one (which had been reconed with a horrid Waldom kit in the 1970s, apparently)... :thmbsp:

Regards,
Gordon.

jackgiff · Dec 13, 2008

Thought I would post some pictures of my HT re-do. It may help some other people who want to change the front panel baffle layout of a pair of cabinets so they will accomodate EconoWaves. The front three cabinets were built several years ago, and used Stephens Trusonic drivers. They were extremely satisfactory, but the urge hit to convert them to EconoWaves. The rear pair is cut out, and front baffles for them are cut. They will be put together soon, and join the 5.1 HT.

The first couple pictures are the Center channel (Stephens Trusonic 80FR), and one of the Fronts (Trusonic 120FR and RT-1 Ring Radiator) before surgery. The Center channel drivers will become a JBL LE111H and an EconoWave using the six inch square waveguide. Since the hole for the 8 inch Trusonic is essentially centered, it will be filled, and epoxied into the baffle so the new drivers cutouts will not need to be compromised by it's placement. The Front channel speakers will now be driven by JBL LE14A's and the standard EconoWave, using the 12 X 6 inch waveguides.

I used round cutouts from other projects to fill the undesired holes in the baffles. They need to be sized just be a little smaller than the hole to be filled. The fillers for the two Front channel cabinets were cutouts made when baffles were cut to hold LE14A's. They just need a slight reduction in size to be perfect. The third picture shows all cabinets lying on their backs, with the fillers supported by a couple small pieces of wood which have been screwed on. The fourth picture shows how the back of the fillers was taped with duct tape, to keep the epoxy from running through the cracks.

The fifth picture shows the first step in filling the gaps around the filler plugs. Epoxy is poured into the cracks to fill and glue the new pieces to the baffle. The last picture shows the inside of the center cabinet after being epoxied. Two batches of epoxy are best, and a third if necessary to fill all the gaps and the old drivers mounting holes, if they will not be cut out when new driver cutouts are made. As shown, the duct tape is aggressive enough to hold tight to the old baffle, and not allow leakage of epoxy.

jackgiff · Dec 13, 2008

Once the epoxy is cured, the excess can be sanded off the baffle fronts, as shown in the first picture. Then the new drivers can be placed on the baffle, and their locations measured and marked. The second picture shows locations of drivers on the Front channels.

The third picture shows the driver placements for the Center speaker, and clearly shows how the old 8 inch speaker hole would have been right in the midst of everything. The fourth picture shows where any rework that has caused disruptions in the baffle face (such as removal of the old grille holding magnets) has been filled with wood filler. I use ZAR Wood Patch. It dries extra hard, and grips like crazy.

The fifth picture is after the final sanding of the baffle, and installation of the driver mounting T-nuts and port tubes. The cabinet edges have been masked for baffle painting. The last picture is after the bafflles have been sprayed with flat black paint. They are now ready for mounting the drivers.

jandg · Dec 14, 2008

Hello, I am itching to try the e-wave gig with a pair of JBL SR 4725's I have in home use with 45 SET driving. The drivers in the sr4725's are 2226H-2426H & 2370 horn. Can I use the 2426 drivers & just tape up the 2370 horn entry..?. The mount the e-wave assembly on top of cabinet..? Also where is everyone sourcing the PT-F95HF from..? I will need screw on adaptors I think as the 2426H are bolted. & finally is there a schematic in this huge thread somewhere. I did look, but can not find it. If anybody knows any XO adjustments that should be made to start off for this combo please let me know. The sr4725 driven with good to great tube gear are superb, so this will be a great A/B test. If the 2426H are not usuable, then please recommend another top flight CD's that would work with project in new or used form.
Thanks for any help.
J & G

dnewma04 · Dec 14, 2008

I heard Ross's advents for all of about 2 mins yesterday at a SMAC meet, I couldn't stay long but they sure did sound nice!

Bauhausler · Dec 14, 2008

dnewma04 said:
I heard Ross's advents for all of about 2 mins yesterday at a SMAC meet, I couldn't stay long but they sure did sound nice!

Thanks, Dave. It was a good meet. I hope you got to hear Wojciek's Azurahorns with modded Lowther DX4s, wood bulb phase plugs and Dennis's EV bass bins. That was quite the thing.

I'll be experimenting with the black foam plugs in the WGs. Keg took them out of Dennis's WGs, put them in mine and we forgot to remove them when we packed up and loaded out.

Room positioning made a huge difference with the Large Advent EWGs at Dennis's place as well as here. On low stands near the wall they're intolerably bassy but a few feet out from the wall they smooth out.

Kegger · Dec 14, 2008

Yes sorry I missed yu Dave, didn't realize you were not staying,

My sentiments follow Ross on the AdWaves, Keep the plugs Ross, as
I believe Dennis is in another area at the moment,

..I'll remake his

PS all your stuff and quite a bit mine is still at Dennis's place.
(Including some new to me BIG JBL's) "thanks Dan"

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