EconoWaveguide Utility Large Advent Build Thread
- Thread starter Bauhausler
- Start date
Altair
New Member
Hi Pete,
I was estimating by ear only... But I just connected the function generator to confirm the numbers, and the result is that I have a nice smooth response down to 20 Hz ! with a slight peak at 45-50 Hz, and a bigger one at 80 Hz. That last one is surely what I "thought" was the one at 40-50 Hz.
As you say, it's probably a room mode.
My amp is a NAD 214 of 80W/8ohms 120W/4ohms.
The preamp is a highly modified NAD 1300.
The room is around 22' x 15', well stuffed, lots of damping materials and things all around, so not much reflections from the back.
Altair
I was estimating by ear only... But I just connected the function generator to confirm the numbers, and the result is that I have a nice smooth response down to 20 Hz ! with a slight peak at 45-50 Hz, and a bigger one at 80 Hz. That last one is surely what I "thought" was the one at 40-50 Hz.
As you say, it's probably a room mode.
My amp is a NAD 214 of 80W/8ohms 120W/4ohms.
The preamp is a highly modified NAD 1300.
The room is around 22' x 15', well stuffed, lots of damping materials and things all around, so not much reflections from the back.
Altair
This might help with room tuning; I don't agree with all of Ethan's theories but this is a start:
http://www.youtube.com/user/EthanWiner#p/u/15/lbLVjHfHahg
Free, simple RTA program:
http://www.libinst.com/SynRTA.htm
http://www.youtube.com/user/EthanWiner#p/u/15/lbLVjHfHahg
Free, simple RTA program:
http://www.libinst.com/SynRTA.htm
I don't see much talk of Room EQ Wizard here, do many use it?
http://www.hometheatershack.com/roomeq/
http://www.hometheatershack.com/roomeq/
Here's a stupid question:
What would be lost/gained if I were to put the Econowave horns on top of some standard Utility New Large Advent cabinets, versus modifying the existing ones? I am not the best woodworker, but would like to build a set of these.
What would be lost/gained if I were to put the Econowave horns on top of some standard Utility New Large Advent cabinets, versus modifying the existing ones? I am not the best woodworker, but would like to build a set of these.
Sir.Byrd
Lunatic Member
just disconnect the tweeter, and flip on their sides to get the woofer the closest to the waveguide.
Good to know.
last stupid question:
Would bridging the terminals on the Zilch crossover (if I built it up with biamp capability) revert it to single amp driving?
I have used it to analyze my room and setup my BFD
but I actually saw more results from multiple sources of bass and some rigid fiberglass bass traps. EQ will get it better in one position, but the bass getting louder and softer as I move around was helped more by the latter.
eratosthenes
Active Member
I am seriously considering e-waving a pair of original Advents. But I have two concerns: 1. The woofers are not original, they are some kind of Utah branded 12" of unknown specification. Certainly more sensitive than the original woofer as they are totally mismatched with the fried egg tweeters. Unanswerable, I'm sure, but how flexible is the ewave design? Can it handle this unknown woofer?
2. I was planning on using a Bottlehead SEX amp as the source. Will the e-wave have the sensitivity (95dB +) and impedance curves needed for a fair match?
2. I was planning on using a Bottlehead SEX amp as the source. Will the e-wave have the sensitivity (95dB +) and impedance curves needed for a fair match?
Bauhausler
Rational Subjectivist
As you suspected, it totally depends on teh woofer. If it was designed for a 2-way system, probably. If it's for a 3-way system it might not have enough top end response to get out to 1600 hz.
The Advent woofer is very good and they're common enough to be available at reasonable cost. One solution would be to get a re-foamed pair of Advent woofers and go that way.
As far as sensitivity, it depends on how loud you want it. The pair of ewaved Advents that I built for the Make magazine article are being used with Audio Note Quest SE 300B amps (around 5 usable watts) and have plenty of volume. I have a power meter on my Ewaves at home and rarely exceed 1W in normal listening.
I haven't done measurements, but I'd guess the sensitivity of the Ewave Advent to be around 86 - 89 db.
As you know, low power tube amps impose severe restrictions on speaker selection.
Gimme a minute and I'll run an impedance sweep and post it.
**** EDIT ****
The curve below should be fairly representative of an ewaved Advent.
Attachments
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eratosthenes
Active Member
Thanks for the info. I will post pics and numbers on those woofers when I can.
eratosthenes
Active Member
princeoftides
Born in Charleston SC
Back in the "good old days", when I built speakers for myself I used to always get a very high quality pair of high quality grey wool felt rings to try out on my tweeters. Heck years and years ago I once even covered the whole baffle in wool just to see what difference it made.
The ones I used back looked fike wool, now I'm not so sure if they were. Maybe just something recycled from something like what they call "fluff" now But they were much more substantial looking than this:
http://www.madisoundspeakerstore.com/acoustic-damping/dampers-felt-defraction-ring-for-tweeters/
Usually, in regards to imaging at least, they seemed better, sometimes not, in those days you had to listen and make up your mind, all this fancy computer measuring stufff wasn't avaiable then. But I always would try them out and usually would like the change. When you couldn't flush mount the driver it was a good way to deal with the screws holding the tweeter.
Are builders using felt rings anymore? The designer at this page seems to think they matter and can be a positive.
http://www.speakerdesign.net/felt/felt_ring_vs_blocks.html
That desingner seems to think they matter and sometimes in a good way. Just seems to me something that retailers would want to offer the option their customers if they're positive. Or is this whole subject one like the "cable debates"? A path that a lot of people prefer they not go down?
The ones I used back looked fike wool, now I'm not so sure if they were. Maybe just something recycled from something like what they call "fluff" now But they were much more substantial looking than this:
http://www.madisoundspeakerstore.com/acoustic-damping/dampers-felt-defraction-ring-for-tweeters/
Usually, in regards to imaging at least, they seemed better, sometimes not, in those days you had to listen and make up your mind, all this fancy computer measuring stufff wasn't avaiable then. But I always would try them out and usually would like the change. When you couldn't flush mount the driver it was a good way to deal with the screws holding the tweeter.
Are builders using felt rings anymore? The designer at this page seems to think they matter and can be a positive.
http://www.speakerdesign.net/felt/felt_ring_vs_blocks.html
That desingner seems to think they matter and sometimes in a good way. Just seems to me something that retailers would want to offer the option their customers if they're positive. Or is this whole subject one like the "cable debates"? A path that a lot of people prefer they not go down?
princeoftides
Born in Charleston SC
Oops wrong thread. I'll put it in the right one.
AuralAbrasns
Member
An older thread but I think that this would be the most appropriate one for my question. I'll be checking out a pair of Advents this weekend with a $40 asking price and they'd make great candidates for my first ewave project, especially since all the hard work has already been done in this very detailed thread. My question is in regards to stuffing the box, I know that fiberglass isn't that expensive but I have a bunch of Roxul (rock wool) sitting around and was wondering if it would make a suitable replacement? I know that it's denser than fiberglass but perhaps that means that I don't have to stuff it as much?
This is very much a budget build for me and I'll be re-using as many components as possible and doing a point to point crossover in order to keep costs to the absolute minimum.
This is very much a budget build for me and I'll be re-using as many components as possible and doing a point to point crossover in order to keep costs to the absolute minimum.
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I just picked up a set of $10 Utility New Advents yesterday and this thread came immediately to mind. I actually heard Bauhausler's originals when he brought them to a SMAC meet years ago.
I've been messing about a bit E-waving various speakers here in an attempt to find something to replace my Altec A7s, but so far, I haven't found anything up to the task. Not that the ewaved speakers didn't sound nice; it's that when level matched, I prefer the A7s.
FWIW, the A7s replaced my original Ewaves, which are Project #11 on the list, and about the only thing I dislike about them is their size. Since I already have the components and have modded the crossovers from my LE14A, it's basically a woodshop project for me with a free box as I had no plans to restore the ULAs beyond refoaming the woofers and flipping all the drivers.
We have had LOTS of Advents pass through here....:yes:
I've been messing about a bit E-waving various speakers here in an attempt to find something to replace my Altec A7s, but so far, I haven't found anything up to the task. Not that the ewaved speakers didn't sound nice; it's that when level matched, I prefer the A7s.
FWIW, the A7s replaced my original Ewaves, which are Project #11 on the list, and about the only thing I dislike about them is their size. Since I already have the components and have modded the crossovers from my LE14A, it's basically a woodshop project for me with a free box as I had no plans to restore the ULAs beyond refoaming the woofers and flipping all the drivers.
We have had LOTS of Advents pass through here....:yes:
