Bring Khorn Top Hats Into Room?

[KdAgain]

In his thread "P. Audio PH-4525 horn and BM-D750 (aka. K69)" Rudy81 has commented on how pulling his new speakers with the double bass bins into the room has greatly improved the soundstage. It got me to thinking that this could be done with the Khorns, except leave the bass bins in the corner where they need to be to properly perform.

In other words take the top hat off the bass bin and put it on some kind of stand that can be brought to a place in the room that gives the best imaging. It could be a little lower than the top of the bass bin to put the top hat near ear height. This of course wont help the low end imaging, but I think most of where we need improvement is from the mid to highs anyway.

Not sure if this obsacle in front of the bass bins might have any negative affect on its output? It also would worsen the existing time alignment problem between the bass bin and the mid/tweet. I plan to go to active crossovers this winter, so will then be able to deal with that issue.

Very curious if anybody has experimented with this approach, and what the results may have been? Or is this just a loco idea?

Rod

[soundbound]

Good solid idea. I've been thinking of trying that someday.

[Chris A]

Very curious if anybody has experimented with this approach, and what the results may have been? Or is this just a loco idea?

Interesting that you mention it...I've been progressively moving my Jubs away from the corners by using horn-loaded subs behind them, and now bass traps on the outside walls to move the Jubs closer to toward the center. The imaging is improved, but some thoughts on your thought:

1) anything that you do to move your Khorns out of the corners will decrease LF performance. I've addressed this problem by having horn-loaded subs behind them in the corners that not only make up for the LF loss, but also extend the response lower by about an octave. They cost me ~$500 in materials to build.

2) If you move top Khorn top hats closer to the listening position than your LF bins, you will create even more delay between the mid/tweeter section and the LF bins. I would more than just recommend using an active crossover (biamping your Khorns) to correct for the path length difference between the two parts of each speaker.

3) The Khorn crosses at about 400 Hz, which is pretty close to the frequency of an "A-440" tuning fork frequency. Moving the mid/tweeter section away from the LF bins means that all frequencies above and below tuning fork frequencies will be "split" into two locations, further confusing your stereo image.

I recommend as an alternative approach building false corners for your Khorns and then move the whole speaker into the room, then using a couple of good subs behind the Khorns to make up for the loss of LF (assuming your listening room is at least 15' wide), using them in the corners that you've just vacated with the Khorns.

Additionally, if you are bringing the Khorns closer to your listening position, the effect of the uncorrected Khorn internal time delays between the LF, midrange, and tweeter will stand in the way of resolving your soundstage image. Bi-amping or tri-amping using a digital active crossover can correct for this and allow you to get very close to your Khorns without loss of the coherency of the sound image.

My $0.02.

[Rudy81]

Up until a week ago, I still had my Khorns. I sold them after I built my DBB's. Had I not sold them, the first thing I would have done is to seal the back of the bass bin. When I was at Hope at the Pilgramige I had a chance to listen to the 60th Anniversary Khorns. I was really impressed with the bass ouput of those Khorns and they were NOT up against the corners. If you look at Picky's thread of the Pigramige, there are a few pictures of those Khorns next to the Palladiums.

I promise you that if you properly seal the back, you will be really imperssed. I would take a look at what Greg did to a set of Khorn bins and try to do the same. His pictues are here http://www.voltiaudio.com/flkhorn.shtml and if you have questions I'm sure Greg would be glad to help.

The idea is that you would then be free to move the Khorns away from the walls. Please let us know how it goes.

[KdAgain]

Thanks guys for all the good observations and suggestions - really appreciate the effort to help!

Interesting about the shift in location between the bass and mid further affecting imaging. No question that time alignement is needed and the system I use when I go 'Active'will allow that. But I am now wondering about imaging problems with a stock Khorn. Besides the long time for the lows compared to mid tweet, there must be some location confusion as a result of the mid tweet being direct and the bass feeding two walls which gives that enveloping low end.

Since we have a Danley DTS-10 monster sub moving the bass bins out may not be such a problem. The sub covers from 11 Hz up to about 100 (if desired). And being a tapped horn it does it with great authority! But since we only have one and it will end up on the side wall we shouldn't cross it too high because of directionality.

I think false corners are probably the proper answer, but since we don't need the bottom end from the Khorns I'm going to consider enclosing the bins a la 60th anniversary edition. Thanks for the links on that. Only thing I'm wondering is that I vaguely recall reading something about losing some upper register bass as well as the lowest end. Think it was around 200. Not sure why this might happen though. In any case enclosing the bins looks like the cheapest and easiest (?) approach and one that hopefully will work fine for us.

We are madly trying to get things ready on our boat for our month long cruise in July. Wont have much internet connection while were gone, so if I ignore any posts here please understand.

Rod

[Chris A]

Since we have a Danley DTS-10 monster sub moving the bass bins out may not be such a problem. The sub covers from 11 Hz up to about 100 (if desired). And being a tapped horn it does it with great authority! But since we only have one and it will end up on the side wall we shouldn't cross it too high because of directionality.

I think that the one DTS-10 will be enough. I'd think about putting the mouth of that sub in a room corner, at least as a test. If you can instrument the response using REW or something like that, you may be able to see the effect.

My guess is that you will be able to cross over at a lower frequency than 100 Hz with the Khorns and DTS-10 even though the Khorns are pulled out in false corners. I'm not sure what frequency that it should be crossed at I'd bet that 50-80 Hz would take care of LF losses due to Khorn repositioning.

The big item, though, is time delay compensation. There is a 7.8 ms delay between the midrange and bass bin (which is huge). There is about a 1.7 ms delay between the tweeter and the midrange (which is significant at that crossover frequency). Correcting these time delays should significantly improve imaging, transient performance (percussion, etc.), and bass performance (bass drum, etc.) while sitting fairly close to the Khorns.

Chris

[twistedcrankcammer]

Very curious if anybody has experimented with this approach, and what the results may have been? Or is this just a loco idea?

Interesting that you mention it...I've been progressively moving my Jubs away from the corners by using horn-loaded subs behind them, and now bass traps on the outside walls to move the Jubs closer to toward the center. The imaging is improved, but some thoughts on your thought:

1) anything that you do to move your Khorns out of the corners will decrease LF performance. I've addressed this problem by having horn-loaded subs behind them in the corners that not only make up for the LF loss, but also extend the response lower by about an octave. They cost me ~$500 in materials to build.

2) If you move top Khorn top hats closer to the listening position than your LF bins, you will create even more delay between the mid/tweeter section and the LF bins. I would more than just recommend using an active crossover (biamping your Khorns) to correct for the path length difference between the two parts of each speaker.

3) The Khorn crosses at about 400 Hz, which is pretty close to the frequency of an "A-440" tuning fork frequency. Moving the mid/tweeter section away from the LF bins means that all frequencies above and below tuning fork frequencies will be "split" into two locations, further confusing your stereo image.

I recommend as an alternative approach building false corners for your Khorns and then move the whole speaker into the room, then using a couple of good subs behind the Khorns to make up for the loss of LF (assuming your listening room is at least 15' wide), using them in the corners that you've just vacated with the Khorns.

Additionally, if you are bringing the Khorns closer to your listening position, the effect of the uncorrected Khorn internal time delays between the LF, midrange, and tweeter will stand in the way of resolving your soundstage image. Bi-amping or tri-amping using a digital active crossover can correct for this and allow you to get very close to your Khorns without loss of the coherency of the sound image.

My $0.02.

Chris,

Did you read the post about putting your sub in the fireplace??

Roger

[Chris A]

Chris, Did you read the post about putting your sub in the fireplace?? Roger

Not in detail - I just glanced at it some time ago. I'd imagine that one got some "flaming" (pun intended).

I remember the same sort of flaming when I proposed putting my TV and center Heresy above the fireplace. BTW - the Heresy and the TV work out well there: they stay cool (I have a thermally reflective barrier on the Heresy, and the mantle blocks the convection from the fireplace). They allow us to watch the fire flicker in the winter when whatever's on the TV gets really boring.

[|-)]