How far back?

[KROCK]

Greetings everyone, I have a pair of LA Scala ll & can anyone tell me what would be the measurement from the outside of the cabinet to the rear of the woofer? I'd like to time align my set up.

Thanks in advance! Dan

 

[wuzzzer]

You'll need to know the unfolded length of the woofer horn.

 

But, didn't PWK say something like "do all the musicians stand in a straight line when playing?" when asked about time alignment?

[billybob]

1 hour ago, KROCK said:

Greetings everyone, I have a pair of LA Scala ll & can anyone tell me what would be the measurement from the outside of the cabinet to the rear of the woofer? I'd like to time align my set up.

Thanks in advance! Dan

 

Good morning!

Yes guess they are basically time aligned. Sure you will get some more information.

Thanks... ☕

[OO1]

9 hours ago, KROCK said:

Greetings everyone, I have a pair of LA Scala ll & can anyone tell me what would be the measurement from the outside of the cabinet to the rear of the woofer? I'd like to time align my set up.

Thanks in advance! Dan

 

 place the bass bin upside down  , remove the woofer-plug cover ,voila the measurements

[KROCK]

Thanks Randy, that's my last resort. I know someone here knows.

[wvu80]

46 minutes ago, KROCK said:

I know someone here knows.

I'm not that expert.  I used to own LS and Khorns and I did the poor man's version of time alignment.  I used an external horn and driver for the tweeter and moved it back along the top to align with the throat of the mid driver  (see pic of Khorn, below.  SEOS 12" waveguide and Denovo DNA 360).  I couldn't hear a difference and I don't know that it made any difference.

 

I've always heard that to time align LS each driver would need to be individually powered and then use a DSP.  After measuring, the DSP would implement the time delay needed for each driver. 

 

All of that is above my pay grade.  Sorry if I wasn't of much help.

 

[captainbeefheart]

We were discussing this in another thread a few months back and I believe we came to the consensus that a delay less than a few mS is not audible. Double blind tests have proven this and there was other empirical data that suggests the same thing.

 

If you are shifting the tweeter back and forth in alignment while you are listening you can hear that due to Doppler effect but when stationary it's not typically detectable by ear.

[captainbeefheart]

1 hour ago, wvu80 said:

I've always heard that to time align LS each driver would need to be individually powered and then use a DSP.  After measuring, the DSP would implement the time delay needed for each driver. 

 

This is true. My research and experience leads me to believe it's mostly an academic exercise unless the delay becomes too large and problematic. In a house I don't see it being a concern due to the fact sound waves through air travel at 13,335 inches/second, If you move the tweeter 12" the time difference is .8mS. Since you can't really start to detect a delay until maybe 3-5mS you would need to move the tweeter a lot. I just don't see moving it back 6" is any way detectable to the human ear.

[Marvel]

The mid/tweeter alignment is more audible and more critcal than the woofer/mid alignment.

 

Once you hear it locked in, why would you move it back. It was very audible and an improvement to the overall sound.

 

 

[KROCK]

This is how I have it now;

10" off the rear wall from what I've tried to gather off drawings on the net.

[OO1]

 The Altec  horn would  need to be moved  back 9.25 inches  based on the depth of the LS II bass bin of  25,25 inches , to get on top of alignment with the   bass bin .

 

http://assets.klipsch.com/product-specsheets/La-Scala-II-Spec-Sheet-v03.pdf

 

 

[OO1]

The tweeter magnet  needs to be aligned with the Midrange driver's magnet   -

[dirtmudd]

7 hours ago, KROCK said:

Thanks Randy, that's my last resort. I know someone here knows.

Light switch, yellow fever, crawling up your bathroom wall Singing psychedelic praises to the depths of a china bowl You've got venom in your stomach, you've got poison in your head You should have listened to the priest at the confession When he offered you the sacred bread He knows, you know, he knows, you know H e knows, you know, but he's got problems Fast feed, crystal fever, swarming through a fractured mind Chilling needles freeze emotion, the blind shall lead the blind You've got venom in you stomach, you've got poison in your head When your conscience whispered, the vein lines stiffened You were walking with the dead He knows, you know, he knows, you know, he knows, you know He's got experience, he's got experience, he knows, you know But he's got problems, problems, problems He knows... slash wrist, scarlet fever, crawled under your bathroom door Pumping arteries ooze their problems through the gap that the razor tore You've got venom in your stomach, you've got poison in your head You should have listened to your analyst's questions When you lay on his leather bed He knows, you know, he knows, you know H he knows, you know, but he's got problems Blank eyes, purple fever, streaming through the frosted pane You learned your lesson far to late from the links in a chemist chain You've got venom in your stomach, you've got poison in your head You should have stayed at home and talked with father Listen to the lies he fed He knows, you know, he knows, you know, He knows, you know, but he's got problems He knows, you know, he knows, you know, he knows, you know He's got experience, he's got experience, he knows, you know You know, you know, you know

[babadono]

Time alignment of drivers is not important or audible....that there is funny.

[babadono]

10 hours ago, babadono said:

Time alignment of drivers is not important or audible....that there is funny.

Tell @Chief bonehead the breaking news.

[Marvel]

17 hours ago, RandyH said:

 The Altec  horn would  need to be moved  back 9.25 inches  based on the depth of the LS II bass bin of  25,25 inches , to get on top of alignment with the   bass bin .

 

http://assets.klipsch.com/product-specsheets/La-Scala-II-Spec-Sheet-v03.pdf

 

 

No, it would be further back. You would need to add the two measurements in blue. It would need to be to the acoustic center of the woofer.

 

 

[Chief bonehead]

On 2/27/2022 at 8:40 AM, wuzzzer said:

You'll need to know the unfolded length of the woofer horn.

 

But, didn't PWK say something like "do all the musicians stand in a straight line when playing?" when asked about time alignment?

He did but then data and listening changed his mind. His friend Richard hyser changed his mind. 

[Chief bonehead]

22 hours ago, captainbeefheart said:

We were discussing this in another thread a few months back and I believe we came to the consensus that a delay less than a few mS is not audible. Double blind tests have proven this and there was other empirical data that suggests the same thing.

 

If you are shifting the tweeter back and forth in alignment while you are listening you can hear that due to Doppler effect but when stationary it's not typically detectable by ear.

My blind tests proved otherwise. 

[OO1]

22 minutes ago, Marvel said:

No, it would be further back. You would need to add the two measurements in blue. It would need to be to the acoustic center of the woofer.

 

I was referencing to back up the Altec 511B Horn as shown in this picture  ⏪  by 9.5 inches   , is that correct  , or should it be even further back  ?

 

[captainbeefheart]

22 minutes ago, Chief bonehead said:

My blind tests proved otherwise. 

 

I left room for the exception by saying it's "not typically detectable by ear".

 

There are many variables and of course a large enough time error will be audible.