Another Hundred Days of Jubilee Ownership

[Coytee]

Can you show me the rest of the floor plan.... it will be help me when I'm lurking about in the dark with your TAD's in my hands to know where all the furniture is hidden, lest I crash over something and wake you up.... [:|] [G]

Your dog doesn't bark does he/she? [&]

[Chris A]

Richard, I'd like to help you out, but...

BTW, Tommy is a real talker...he yodels. He'll demand to play ball until dawn...

Chris

Edited November 10, 2013 by Cask05

[whatever55]

Room position: About mid-summer, Roy Delgado mentioned that having anything between the the Jubs really affects imaging performance (...he wasn't kidding, BTW). I now have the Jubs pulled out from the front wall about 16" and pulled inwards toward the center about 5" from the side walls. The space behind the Jubs is now filled with tapped-horn subs in each corner, which forms a false corner behind the Jubs. The side gaps are now filled with bass-trap panels. This forms the other side of a false corner, but provides a gap behind the back of the Jub bin in which the mouth of the subs can feed with the back of the Jubs and the side bass trap panels forming a kind of tapped-horn path extension. I used Audyssey to set up the delays and the levels only, not EQ. Note that I'm using active crossover for the Jubs and the center channel. The difference in imaging is like that between the living and the dead.

How big is the sweet spot ?

How far apart are the Jubs / listening distance from center ?

I have a spot where they dissappear but if I even move my head too far to one side I hear more of that side.

What center speaker are you using ?

[Chris A]

How big is the sweet spot?

It's wider than the Khorns were in my room by a large measure. I'm assuming that you are talking about imaging with the center-channel images centered in front. The Khorns never really imaged like the Jubs do now, but this was probably related to that fact that I had the Khorns in the corners.

How far apart are the Jubs / listening distance from center?

The Jubs are currently ~14.5 feet apart (outside-to-outside of cabinets). The front-row listening position is about 10 8 feet from each Jub.

I have a spot where they disappear but if I even move my head too far to one side I hear more of that side.

That seems to be part of the stereo effect psychophysics and why center-channel speakers are used extensively. However, you can sit within a foot or so of center and still sense a centered image. You can walk toward the front of the room on centerline and still hear a definite centered image (like it is coming from the center channel speaker instead of the Jubs) up to within a foot from the mantle. It also sounds really good at the back of the room (~38 feet back).

What center speaker are you using?

Look in my profile listing.

[Chris A]

Room position: About mid-summer, Roy Delgado mentioned that having anything between the the Jubs really affects imaging performance (...he wasn't kidding, BTW). I now have the Jubs pulled out from the front wall about 16" and pulled inwards toward the center about 5" from the side walls. The space behind the Jubs is now filled with tapped-horn subs in each corner, which forms a false corner behind the Jubs. The side gaps are now filled with bass-trap panels...BTW, this technique will also work for Khorns, but you’ll have to push the Khorns back into the subs a bit tighter.

One thing that I didn't mention was that I added more absorption material between the Jubs to suppress reflections off of the masonry. The more that I add, the greater the imaging but the smaller the room feels--so there is a tradeoff. I'm presently using bass traps up against the masonry while I continue to look for a long-term solution. Controlling reflections off of the mantle and flat screen TV also increases imaging (vertically) by a large measure. I'm pretty sure that many people here didn't want to hear that, but...

Moving the Jubs toward the center very slightly results in reduced side-wall reflections from the K402s, and increased the imaging as much as moving the Jubs away from the front wall to get the K402 horns in front of the mantle, flat screen, and mansonry. This is fairly interesting in that the K402 horns can control their polar response down to well below their crossover frequency (about 400 Hz to the Jub bass bins). If this works for a K402, my guess is that it would work much better for a Khorn, which doesn't really control its polars in midrange down to 450 Hz. There is both ceiling/floor bounce and side-wall bounce present in Khorns that doesn't occur with the K402 horn.

Chris

Edited November 10, 2013 by Cask05

[Chris A]

On second thought, what kind of stuffing would absorb 45 Hz and below? [:^)] I'm assuming that fibrefill would have some effect (you can see the effects on the SPUD DIYaudio thread) but I'm not sure how to calculate the amount needed--if any.

I guess it's going to be cut-and-try to find out...[*-)]

Chris