12 replies to this topic

[RoyC]

OK, I did it...Curiosity got the best of me!

For the past 15 years my greatest audio related enjoyment has been derived from the restoration of "classic" speakers, especially early ARs, but I have been an inveterate "speaker tinkerer" for decades. With the positive reviews of the "Ewave" DYI project over in the Audiokarma forum, and the references made to the concept in recent techno-debates here at CSP, I just had to go for it. http://audiokarma.or...214#post1856214.

Below are some photos of a pair of Avid 102s, which have been transformed into what we old timers used to refer to as "horn" speakers. The modern term would be "waveguide" speakers. AK's "Ewave" is an economy/inexpensive do-it-yourself two-way speaker project, mating a pre-engineered waveguide/compression tweeter/crossover to an existing cabinet and woofer of one's choosing. Much thanks goes to "Kitchen" resident Zilch, co-developer of the "Ewave", for his guidance and crossover boards! The project was simple, but mating the woofer to the new tweeter is not as easy as connecting everything to the crossover board! Every woofer is different, and unless one has room measurement devices and/or some experience working with crossovers for tweaking purposes, it is probably best to go with a woofer already proven to work with the Ewave crossover and high range driver combo. I made adjustments to the the generic woofer section of the Ewave crossover.

I also went with the bi-amping option. Along with whatever advantages bi-amping offers, it separates the woofer circuit to make it easier for tweaking, or the experimentation with other woofers in the future. There are 2 Audiosource Amp 100s connected to them at the moment. (BTW, Audiosource amplifiers are inexpensive, high current amps, great for classic speakers...The AMP 100 level control, provides further flexibility http://www.parts-exp...tnumber=302-601 )

I have only been listening on and off for a couple of days, so I'm still getting a feel for them, but they are easily worth more than the effort it took to construct them! I am a fan of the late 70's Avids, and these are superior, to my ear, to the 102s they replace. The excellent Avid woofer and extremely "waveguide-friendly", wide Avid cabinet baffle made this project go very smoothly.

Uh, yes that is an AR pot level control knob installed on the l-pad, and I DO own other "unharmed" Avids.

Roy

[Zilch]

Every woofer is different, and unless one has room measurement devices and/or some experience working with crossovers for tweaking purposes, it is probably best to go with a woofer already proven to work with the Ewave crossover and high range driver combo. I made adjustments to the the generic woofer section of the Ewave crossover.

VERY nicely done, Roy! You "adjusted" the grille for the waveguide, no?

Advents, particularly, have also become a popular E'Wave upgrade platform on AK:

http://audiokarma.or...ad.php?t=196614

[Carlspeak]

Roy:
E-wave technology is based on a compression driver behind the waveguide. The KEY question is: how does the compression driver sound compared to a dome tweeter? Particularly with high quality acoustic recordings played thru them.

Second question: You converted a 3-way to a two way. Many of the e-wave projects over at AK are based on converting a 2-way to a 2-way. Was it difficult to compromise the crossover with the 3-way woofer?

[RoyC]

Roy:
E-wave technology is based on a compression driver behind the waveguide. The KEY question is: how does the compression driver sound compared to a dome tweeter? Particularly with high quality acoustic recordings played thru them.

Second question: You converted a 3-way to a two way. Many of the e-wave projects over at AK are based on converting a 2-way to a 2-way. Was it difficult to compromise the crossover with the 3-way woofer?

Carl, take a closer look at the first photo. The 102 is a 2-way speaker. The front baffle also contains the level control switch and fuse. (The very similar 103 is the 3-way version of the 102, and is one of my favorite classic speakers.) The 102s I used date to June, 1979 and are comparable to the Large Advent and AR-14.

It is too early in the game to make any (subjective) definitive statements, and the last thing I want to do is turn this thread into another debate. Having some experience with horn-type PA speakers, I can safely say that these do NOT sound like those...which was a pleasant surprise. The first thing that struck me was the excellent balance and clarity compared to the stock 102s. Another early observation is that the dispersion issue does not seem to be the problem I was expecting it to be...Then again, having experimented with a number of potential replacement dome tweeters for the AR-3a, I believe the concern about a modern 1" tweeter's ability to replace the 3a tweeter's dispersion attributes is overstated, so maybe I am not tuned into "dispersion" problems. The Ewaves sound fine in a number of listening positions.

Zilch...Thanks...and thanks again for your assistance and patience.
The Avid grilles are constructed of sturdy 1/2" mdf. I propped up the grille in one photo to show how it will look...will have to cut out a hole for the waveguide to make it fit properly, which means replacing the grille cloth.

Roy

[Carlspeak]

Carl, take a closer look at the first photo. The 102 is a 2-way speaker. The front baffle also contains the level control switch and fuse. (The very similar 103 is the 3-way version of the 102, and is one of my favorite classic speakers.) The 102s I used date to June, 1979 and are comparable to the Large Advent and AR-14.

It is too early in the game to make any (subjective) definitive statements, and the last thing I want to do is turn this thread into another debate. Having some experience with horn-type PA speakers, I can safely say that these do NOT sound like those...which was a pleasant surprise. The first thing that struck me was the excellent balance and clarity compared to the stock 102s. Another early observation is that the dispersion issue does not seem to be the problem I was expecting it to be...Then again, having experimented with a number of potential replacement dome tweeters for the AR-3a, I believe the concern about a modern 1" tweeter's ability to replace the 3a tweeter's dispersion attributes is overstated, so maybe I am not tuned into "dispersion" problems. The Ewaves sound fine in a number of listening positions.

Zilch...Thanks...and thanks again for your assistance and patience.
The Avid grilles are constructed of sturdy 1/2" mdf. I propped up the grille in one photo to show how it will look...will have to cut out a hole for the waveguide to make it fit properly, which means replacing the grille cloth.

Roy

Ooops, sorry Roy. I didn't enlarge the pic of the orig. before the mod. The level control area just looked like another driver to me.

[Zilch]

http://howto.wired.c...intage_Speakers

[dingus]

dang Zilch, they should have got you to do the how-to video. after watching it i think it actually is as easy as it looks. i'll have to give it whirl one of these days, but first i'll have to find some boxes with bumpin' bass.

[Zilch]

I'll have to find some boxes with bumpin' bass.

It's a technical term, actually.

You gotta measure to be sure you have it.

(Clue: look for a Qtc of 1.0 or above.... )

[Pete B]

Sorry, off topic:
The obvious high end woofer would be a JBL type, but have you considered the offerings from
John and Nick of AE? These are mighty impressive drivers at a good price. They have very long
throw, but also shorting rings and cones designed so that they'll play with low distortion up into
the midrange.

These with the Ewave horn should be rather amazing. They make many variations on their
10, 12, 15 inch drivers and there were some older models that worked well in small sealed
boxes. They'll do the older drivers if you ask for them, and 4 ohm types also. I've not tried
them yet. Any experience with them Zilch?
http://www.aespeakers.com/

Thread at DIYaudio about them:
http://www.diyaudio........&highlight=

One designer said this about them:
"I have to jump on John J.'s bandwagon here - the Lambda woofers he is making are very special drivers, capable of doing things that most drivers can not begin to touch. For example their ability to reach deep in the bass with a good Xmax, and at the same time maintain extremely low non-linear distortion values into the midrange are pretty much unprecedented. The 12" I used had the Le of 4" driver and had a flat response on-axis to 2.5kHz. The Lambda will give you bass slam and a low distortion mid that can cross effectively to a dedicated midrange that you will not get with hardly any other woofer."

[Zilch]

Hi, Pete!

I have no experience, but Dave Newman on AK is working with them, and Augerpro on AVS is running some tests, next week, I believe. John's a member there, and may have some comments on the results. They're certainly high on my "Try next" list, along with some of the newer JBL woofers.

I've also got a bunch of other compression drivers and waveguides lined up here, and more coming in all the time. In preliminary testing, I liked the B&C DE250s, and want to get the 18-Sound ellipticals running in something here soon. It's looking like those are going in AR1s....

[chicks]

(The very similar 103 is the 3-way version of the 102, and is one of my favorite classic speakers.) The 102s I used date to June, 1979 and are comparable to the Large Advent and AR-14.

It is too early in the game to make any (subjective) definitive statements, and the last thing I want to do is turn this thread into another debate. Having some experience with horn-type PA speakers, I can safely say that these do NOT sound like those...which was a pleasant surprise. The first thing that struck me was the excellent balance and clarity compared to the stock 102s. Another early observation is that the dispersion issue does not seem to be the problem I was expecting it to be...Then again, having experimented with a number of potential replacement dome tweeters for the AR-3a, I believe the concern about a modern 1" tweeter's ability to replace the 3a tweeter's dispersion attributes is overstated, so maybe I am not tuned into "dispersion" problems. The Ewaves sound fine in a number of listening positions.

I picked up a pair of the Avid 102's for < $30 at the GW, they sound quite nice to me, comparable to my NLA's. I've looked at E-waving these, but the price, to me, is not exactly "econo". So, I'm curious as to whether this mod has improved the 102's to the point where you prefer them to the 103's, or even AR-3a's, or some other higher-end speakers. Would also be interested in how much of the improvement is due to the horn, and how much can be attributed to bi-amping.

The real test, I suppose - have they become your primary speakers?

Thanks.

[RoyC]

I picked up a pair of the Avid 102's for < $30 at the GW, they sound quite nice to me, comparable to my NLA's. I've looked at E-waving these, but the price, to me, is not exactly "econo". So, I'm curious as to whether this mod has improved the 102's to the point where you prefer them to the 103's, or even AR-3a's, or some other higher-end speakers. Would also be interested in how much of the improvement is due to the horn, and how much can be attributed to bi-amping.

The real test, I suppose - have they become your primary speakers?

Thanks.

The e'waved Avid 102s have not replaced any of my favorite speakers, such as the 103. My "primary speakers", however, change quite often as I complete restorations, and I enjoy a variety of systems on a regular basis. I used the e'waved 102s in a small room at low to moderate volume levels, and found them to be very satisfying. They also seem less affected by room placement than my other speakers. One downside is that the upper midrange gets somewhat harsh at higher levels, especially compared to the reticent, classic ARs. Bi-amping did not prove to make a difference in my application.

I found the project interesting and worthwhile, but, being a restoration guy, I am not one to encourage you to tear into a popular design like the Avid 102 if you are enjoying it as is.

Roy

[chicks]

Thanks, RoyC. I'm probably as much econophile as audiophile; I can certainly hear the differences between my Advents, AR-2a's and Avids, but quite enjoy the sound of all three. I'm much more able to put time than money into these, though the Avids haven't required any restoration time (rubber surrounds, near-perfect vinyl veneer and grilles). Enjoyed every minute of the many hours spent redoing the AR-2a's, though - very rewarding and satisfying hours. Just wish I had the room to rescue more of these classics from the thrifts and CL.