Acapella vs. Avantgarde

Any placement behind the horn will exaggerate time arrival issues.

Most often shows up as cancellation (dip in freq. response) somewhere between the woofers and the horn, based on distance as well as the chosen crossover point.

Technically, from a timing standpoint, the woofer should actually be forward(!) of the horns.

Since the woofers are crossing as high as the do (shorter wavelengths), too much time offset will detrimentally affect the sound hanging together from horn to sub.

That said, I've placed them futher back on occasion because the bass was so abysmal where they "should" have gone, that the correct time arrival was offset by truly bad bass...

So it's almost always a trade-off...

Best regards,

Jim Smith

Jim, are you agreeing with my sub placement as an acceptable trade off. How do you set your subs and horns in your room. Could you please include dimensions. As others have stated earlier I really appreciate hearing your recomendation and opinions. Are you enjoying the audio world at the user level more now than you did at the business end of it. What a crazy fun hobby. Couldn't go without it.

Steve.

Jim, are you agreeing with my sub placement as an acceptable trade off.

Unfortunately, I can't agree or disagree. Without being in your room, and seeing what placement works best, I can't possibly know.

Have you tried inverting the polarity on all 4 subs, to see if that's an improvement? Sometimes with them located behind the horns, it'll help.

If you can't run pink noise with a 1/3 octave RTA, then play some recordings with simply miked solo vocals. If female vocal, use one that's fairly low. The ubiquitous Diana Krall can work.

Listen with all of the subs in one polarity. Note how present the vocalist is.

Then invert the subs. Without adjusting the volume control, play the same recording again.

Very often, one way will sound a bit hollow, and the other way will sound more palpable and present. Hollow is phase cancellation, so you don't want that configuration.

If you're using a jumper to go over to a pair of subs per channel, just invert the polarity at the amp end. It'll take care of both. Obviously, do this for both channels.

How do you set your subs and horns in your room. Could you please include dimensions.

What happens in any room is only a function of that room, and usually will have little bearing on another installation. So I'd prefer not to introduce any potentially confusing tips that may likely cause more trouble than they solve...

Incidentally, this technique is not at all unique to Avantgardes. I remember going through a similar process with the Mark Levinson HQD (Hartley subs, Quad mids, Decca tweeters) system in 1978. And countless systems since.

A lot has changed since then, but the basic laws of physics still have to be obeyed... :)

Best regards,

Jim Smith

Thanks Jim, I'll try that. My pre went back to the factory for some up dates. My system will be down for a while. I'll give that a try as soon as it gets back.
Steve.

I own a pair of AG UNOs and agree with many here, specially regarding proper placement, top-notch electronics (no - you wont save on amps if you get AG - I have been there) and the sub-horn alchemy.

i) AG is quite directional, I am still fine tunning after six months!
ii) AG cables make a difference in the subs, I have tried a dozen, Siltech worked for me.
iii) AG are addictive, whatever I hear, including a friends pipedreams or Avalon Eidoleons, sound boxed and laid back in comparison - (eg. yes, there is an AG "sound").

My next step is to try Magellan VIII subs (thanks for reading this post) - A good friend of mine is comming tomorrow to compare my system with his (Acappellas involved) - will post his remarks shortly after.

Enjoy!

Fernando