Avantgarde modifications?

Let me offer you what I know, which may not answer your question. Mapleshade made a few heavy duty frames for the Duo back in the day to accomplish two things; rigidity and the ability to separate the horns from the integrated woofer. There weren’t many made and those that were are scarce. You can, with the right craftsman or welding skills, fashion your own.

I took a different approach- I didn’t dissemble my Duos but added subs-a pair of 15 inch Rythmiks which supplement the otherwise intact factory speaker. I run them in parallel with the main system, DSP’d the subs at low cost and it integrated well.

The Duo presents a dilemma-- get them to produce bass and they sound discontinuous with the mid horn. Blend them to cohere with the mid horn and they are bass shy.

If you don’t want to take your speakers apart and fashion a new frame, leave ’em be, and add big subs. I DSP’d the subs, and they run from a separate output from my line stage. It took a little effort to blend the subs to the integrated woofers, but it is well within the capability of the units as they come from the factory. If the integrated woofers die, Rhythmik also makes a mid woofer which should work perfectly as a replacement for the integrated woofer. (I’m not sure they will give you foundational bass but will accomplish what you ask) The advantages:

• you are not frankensteining your Avantgardes;
• you can place the mid subs wherever you want, as long as you have a jumper to reach them;

the real foundation is laid down by the bigger subs- I don’t regard the integrated woofers as subs, more as woofers. I DSP’d the subs without any additional electronics on the main speakers. It wasn’t that hard to get the subs to cohere with the integrated AV woofer system- phase, gain, crossover frequency and slope. (I run the subs at around 50-55 hz with a 24 db/octave slope).

This gives me a full range speaker, intact, with the additional benefit of bass supplementation that the AV’s simply can’t do. The system, which started in 2006-7 sounds more like real music on acoustic instruments-- jazz- than it ever has.

Maybe this will cost more money than detaching your Uno’s from the bass modules, but I found this a good workaround. And if the plate amps in the integrated woofers die, I will buy that mid bass woofer from Rhythmik and hook them up instead of the factory woofer system, leaving it to function as part of the frame.

Does this make sense to you?

It doesn’t address tweeter placement. Jim Smith has posted about his experiments with that. The newest version of the Trio has a sliding platform to align the tweeter, front to back, for better time alignment. You might look into that as well.

The retail price of these speakers has gone haywire. So, an older pair of Avantgardes in good order is a fine starting point. I have not experimented with moving the tweeter, but it can be done. Look at the new Trio for a starting point.

Interesting: If low, flip horns upside down to keep/aim 'higher' tweeters to seated ear height would definitely work, however,

you might consider turning them sideways, tweeters inside, mid horns outside to preserve height dispersion relative to any furnishings and keep the mid horn reflections higher above the floor and at same ear height as tweeters.

Keep woofers close to horns, as bass overtones become stereo, and thus you want bass emanating from ’same’ location for imaging. 

Toe-In of course to preserve both equal volume dispersion (like published measurements) and avoid/minimize side wall reflections.

If listen with a friend, i.e. two chairs off center, add skid material or 3 wheels to easily alter toe-in of horn section: aim left speaker at right chair/right speaker at left chair, preserves Imaging much better than primary toe-in for single centered chair.

If possible, you could attach the two 'sideways adjacent' woofer/horns so altering toe-in moves bass with horns, important only for directional upper bass from your sub-woofer cabinets. Not too important, just a consideration.

Thanks for those response which have given me further thoughts to consider. If I do proceed with modifications I will report on the results.