How does rake adjustment affect sonics?

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jimbill

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I put my spiked speakers on 1" planks so that they are easier to move on our wooden floors. Also, our sofa has noticeably "deepened" in the sweet spot sitting position. So I raised the back of the speakers about half an inch.

In theory, does this change the presentation or the sound?
 

Russr

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Howdy, fellow Houston-ite!

First question: Which speakers?
Secondly, describe or show pics of this sliding apparatus - might be having a bigger impact on your sound than the potential benefit of the rake.

Russ
 

jimbill

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13a's. Simply a 1x12 piece of finished oak approximately the same size as the bottom of the speakers. The spikes are sitting directly on the solid piece of wood.

Regardless, my question was how does changing the rake angle affect the sound of the speakers in general?
 

Brandon Hartwick

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13a's. Simply a 1x12 piece of finished oak approximately the same size as the bottom of the speakers. The spikes are sitting directly on the solid piece of wood.

Regardless, my question was how does changing the rake angle affect the sound of the speakers in general?
My experience with electrostatics is that they're very sensitive to placement, changing the rake angle could definitely have an impact on cound stage. I would recommend playing with it a bit and see what you like best, try one position for a week and so on.
 

Brad225

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I would suggest placing a carpentry framing square on the center, in both directions on the face of each speaker panel.
Adjust so the face of the speaker is 90 degrees to your ear. The top leg of the square should be pointing directly at your ears.

That will at least give you a signal that is arriving to you at the same time. If the speaker is leaned back and you’re listening to the bottom of the speaker everything is arriving at a different time, although fractions of a second, it does make a difference.

Try it and see
 

sgordon10

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"EVERYTHING can make a difference" also means "If you can hear a difference, then there is a difference."

Lowe's sells many different packages of inexpensive shims. I had to measure the distance to the ceiling,
with a laser, to try to create a level surface in my converted-garage listening room. These shims can adjust the rake, also. It is apparent (to me) that barely measurable changes can make all the difference in delivering emotionally-satisfying music, from the Expression ESL 13a!

Remember the killer line, repeated a few times, in the movie "Thelma and Louise?"
YOU GET WHAT YOU SETTLED FOR
 

sleepysurf

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The ideal rake angle is highly dependent on distance to your primary listening position, as well as speaker distance from front wall, toe-in, and seat/ear height, so you need to experiment with your specific room.

I've found it easiest to measure the angle of the panel using a digital protractor like this... https://www.amazon.com/Johnson-Leve...73500&s=hi&sprefix=johnson+,tools,170&sr=1-24. It doesn't matter whether you place it flat against the top or bottom of the panel, as the angle is constant.

My main listening position is ~10 ft from each speaker. I'm currently using a 5° backward rake angle, but have also used 3° in the past.
 

Robert D

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The ideal rake angle is highly dependent on distance to your primary listening position, as well as speaker distance from front wall, toe-in, and seat/ear height, so you need to experiment with your specific room.

I've found it easiest to measure the angle of the panel using a digital protractor like this... https://www.amazon.com/Johnson-Leve...73500&s=hi&sprefix=johnson+,tools,170&sr=1-24. It doesn't matter whether you place it flat against the top or bottom of the panel, as the angle is constant.

My main listening position is ~10 ft from each speaker. I'm currently using a 5° backward rake angle, but have also used 3° in the past.
I'm guessing the farther back you are ,the greater the rake angle?
 

Robert D

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Correct.

I just used a tape measure to set mine up, just gotta be very particular on how you measure and what you measure to.
Is there a way to calculate the angle needed? I guess it's probably just best to go by how it sounds. I've never messed with it. My Prodigy speakers just sit as they do from the factory.
 

rrussell

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IF the 90 degree hypothesis is optimal, an easy and precise way to achieve it is to take a laser pointer with a flat back end and place it on the middle of the panel and adjust tilt angle until the beam is at ear height.
 

Tenacity

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I would suggest placing a carpentry framing square on the center, in both directions on the face of each speaker panel.
Adjust so the face of the speaker is 90 degrees to your ear. The top leg of the square should be pointing directly at your ears.

That will at least give you a signal that is arriving to you at the same time. If the speaker is leaned back and you’re listening to the bottom of the speaker everything is arriving at a different time, although fractions of a second, it does make a difference.

Try it and see
Good point hadn't thought of it that way, but have mine adjusted like that from listening tests.
 

ttocs

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I've got one of these. Easy to use. Just plop it down, unlock the laser, and it emits a plumb line, and level line. Point it at the speaker just a few inches away and measure high and low on the stat panel to get the difference at a known distance. For example, if you measure two points separated by 24", then, when the top measurement point is back from the bottom measurement point by 7/16", it is a few ticks over 1º of rake. A difference of 7/8" is 2.09º, 1-1/4"=2.98º so it's right at about 3º, and so on.

laser-level.jpg



Here are examples of degrees to inches conversion when using 2' rise (the vertical part of the equation) if you want to know what the degree of rake is, or what you want to aim for:
1.06º = 7/16"
2.09º = 7/8"
2.98º = 1-1/4"
4.01º = 1-11/16"
5.06º = 2-1/8"

These measurements are close enough. But a dimension that's much closer to 1º is 27/64", which actually equals 1.01º. So just use 27/64" and multiply by however many degrees you want, then convert to an easier number more commonly seen on rulers. More precision than is needed, but fun to know.

I just measure the offset from plumb, match both speakers, then tweak that with a flashlight from my seat to get the reflection at the same height by eye.
 

Tenacity

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When I'm stood doing things in the listening room the sound is slightly off. However when sat to listen the sound is all there as I have set the the panels to get the best sound when sat. It is sounds great when you take the time and trouble to adjust the rake. Just wish I'd had a pair of helping hands to make the adjustment that bit quicker ;-D. I'd even thought they might sound even better slightly tilted forward as my head is rested back on the chair, but that might be a lean to far.
 

Russr

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Question for y'all: Once you've established optimal rake angle, how do you make it permanent, and how do you isolate the speakers in a way that does not introduce low frequency vibrations from extra pieces of wood, etc.?

In my case, wih SL3's and Aerius's, I have the spikes resting on 80lb pavers that sit on top of a wood floor. Not ideal, but it seems to have good results. I'm wondering if you can just use the spikes (screwed in to different depths front vs. rear) to get the desired angle?
 

JETHRO

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My experience with electrostatics is that they're very sensitive to placement, changing the rake angle could definitely have an impact on cound stage. I would recommend playing with it a bit and see what you like best, try one position for a week and so on.
I am very close to my 13s and found raking the speakers more forward made an enormous improvement. I am looking forward to improving it even more with techniques shared here.
 

Tenacity

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Question for y'all: Once you've established optimal rake angle, how do you make it permanent, and how do you isolate the speakers in a way that does not introduce low frequency vibrations from extra pieces of wood, etc.?

In my case, wih SL3's and Aerius's, I have the spikes resting on 80lb pavers that sit on top of a wood floor. Not ideal, but it seems to have good results. I'm wondering if you can just use the spikes (screwed in to different depths front vs. rear) to get the desired angle?
Well I have mine stood on Townshend Isolation Platforms, they are level and speaker spikes give the rake and superb sound.
 

Brandon Hartwick

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I am very close to my 13s and found raking the speakers more forward made an enormous improvement. I am looking forward to improving it even more with techniques shared here.
The biggest recommendation is just to mess around with placement and make sure to record your results. I have found my Aerius I speakers react to placement much different than any other speaker I've used, so don't be afraid to try some placements that might seem counterintuitive.
 

JonFo

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Good discussion and great suggestions so far.

I'll add that the ideal is a pure vertical rake, as that engages the fewest room reflections. So for some of the newer, shorter models, one thing to consider is placing them on a riser that places your seated ears at roughly 2/3 of the way up the panel height.
 

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