Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How To Interpret Graphs - Page 360 - AVS Forum
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post #10771 of 10776 Old Today, 11:46 AM
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Originally Posted by AustinJerry View Post
It is not obvious from the room mode calculator that the 45Hz dip is associated with any of the room dimensions.
That's strange Jerry because the REW room sim clearly shows the 45hz dip...unless the sub is located in the back 1/4 of the room.
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post #10772 of 10776 Old Today, 12:32 PM
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I am not familiar with how the room simulator works. However, the formulas in the room mode calculator are simple mathematics, and are accurate.
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post #10773 of 10776 Old Today, 12:36 PM
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Originally Posted by jim19611961 View Post
That is easier said than done. Unfortunately, they dont explain how to graph the results in a comparative and helpful way. Instead, they want you to pay $75 for their analysis
Did you listen to the test signal over headphones? How does it compare to how it sounds when played back on your speakers?

Markus

"In science, contrary evidence causes one to question a theory. In religion, contrary evidence causes one to question the evidence." - Floyd Toole
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post #10774 of 10776 Old Today, 02:33 PM
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Originally Posted by AustinJerry View Post
I am not familiar with how the room simulator works. However, the formulas in the room mode calculator are simple mathematics, and are accurate.
the room mode calculator just tells you where the modes are, the rew room sim solves for modes and the listening position (and delays etc dialled into each source).

As far as I can see, placing the MLP and the sub at the same distances from each wall (at 1/3 the length) produces that dip at 45Hz. I'm not entirely sure why.

room_sim.JPG

It doesn't look a great room for 1 sub tbh, how big is the listening area? do you have multiple rows of seats? for a single seating position, sitting at 1/5 the distance from the rear wall and a sub in the corner looks about as good as you can expect.

room_sim_2.JPG
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post #10775 of 10776 Old Today, 02:57 PM
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OK, let's see if he tries that, and what the measurements show. It will be interesting to see how accurate the room simulator is. It should work reasonably well in a rectangular sealed listening room. I have an open floor plan, and such simulators are of no use whatsoever, unfortunately.
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post #10776 of 10776 Old Today, 11:03 PM
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Originally Posted by HDgaming42 View Post
I was shocked running REW with my new sub (empty room) to find a nasty nasty null. I've moved both my MLP and sub around to a number of positions and could use some guidance. My room's dimensions aren't THAT far off a recommended ratio--or so I thought.
Well... room dimensions ratio... My understanding...

A room (enclosed space) is going to have nodes - frequencies that produce standing waves due to reflections. A Cube is usually quoted as the worst, same nodes in all directions, so they reinforce each other. I suppose a sphere would be the ultimate bad room.


The recommended room dimension ratios don't eliminate nodes, but, the nodes for end to end, side to side, floor to ceiling, and the angular reflections, occur at a range of frequencies, not falling on top of each other, not reinforcing each other.

I suppose if the room is bumpy enough it looks smoother, as opposed to one with a few totally black holes in the response.

Close your eyes and see if what you HEAR is as bad as what you think you see when you MEASURE, and go from there.

Musical intruments are not one frequency, they have harmonics and overtones. The ear/brain is adept at filling in the gaps.

I have a big hole at 55hz, and never guessed until I measured it. Didn't notice anything wrong. Now chasing it. That's the hobby.

If you want no nodes, you need an anechoic chamber.

I see the science boys have created the blackest material yet, almost no reflectivity/emission for light. Maybe somebody is working on the same for sound.

https://en.wikipedia.org/wiki/Room_modes

I'll be back later...

equitech 1.5RQ -> various digital sources > benchmark > krell pre and monoblocks > reQuest

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