What you have not told us is what the measurement conditions are. Is this far field? It is gated MLS type? Pink noise? Sweep? How far away is the mic? Is the mic calibrated?
Every combination of measurements tells us something different. What the above graph tells me is your sound card works. Without understanding what you are measuring and how, it tells me nothing else. Are the speakers ported or sealed? In line with the tweeter or woofer?
Wondering , why do you want an SPL meter? Not very useful for speaker design and tuning.
Every combination of measurements tells us something different. What the above graph tells me is your sound card works. Without understanding what you are measuring and how, it tells me nothing else. Are the speakers ported or sealed? In line with the tweeter or woofer?
Wondering , why do you want an SPL meter? Not very useful for speaker design and tuning.
You are measuring the room, not the speaker. Measure at about 300mm and at 1M and see what the changes are. You still did not tell us how this was made. Is it an MLS pulse ( go download ARTA ) or is this pink noise, or is it a sweep. Each method is useful for different things. Unless the speaker is on a 30 foot pole in the air, you are measuring the room.
To understand measuring, pick up a copy of Measuring Loudspeakers ( clever name eh? ) by Joe D-Apolitto.
If you are not doing health and safety inspections, I don't know what a calibrated SPL meter is good for. I have one. I think the only thing I used it for in the last 10 years was to show a local bar owner he was endangering his employees health by letting bands control their own volume. Never used it for speaker design.
To understand measuring, pick up a copy of Measuring Loudspeakers ( clever name eh? ) by Joe D-Apolitto.
If you are not doing health and safety inspections, I don't know what a calibrated SPL meter is good for. I have one. I think the only thing I used it for in the last 10 years was to show a local bar owner he was endangering his employees health by letting bands control their own volume. Never used it for speaker design.
Looks like REW so it should be a logarithmic swept sine measurement I'd guess. I'd also be suspicious about it being a three way with the need for the mid to be reversed in polarity 
(having been there done that with my first measurement ---> http://www.diyaudio.com/forums/mult...orkshop-microphone-invaluable.html#post273443 )
edit. that new plot doesn't look as bad, did you change the mic position to be closer to the speaker?
Tony.
(having been there done that with my first measurement ---> http://www.diyaudio.com/forums/mult...orkshop-microphone-invaluable.html#post273443 ) edit. that new plot doesn't look as bad, did you change the mic position to be closer to the speaker?
Tony.
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You really need to change to MLS type measurements. Sweep is great for below 200, but above that, to separate the room from the speaker, you need a gated pulse. Download ARTA and measure at one foot and one meter as well as your listening position. You will learn a lot. Remember, measurements are to give you a hint to make it easy to tune for your ears in your room. My complements you realize it is your speaker in your room to your ear. So many get carried away with the measurements hay forget this most basic advantage of DIY.
The above sweep looks darn good. 500 Hz is within the range of absorbers. The only time I have had a room with a single big peak it was a cavity next to a fireplace. I put a door over it and it smoothed out. ( about 1K) Have you moved the speakers around a little? It is a bit of an art making a living room into a listening room while maintaining WAF. It is worth the effort as you will learn so much about acoustics, as well as the benefits of WAF.
The above sweep looks darn good. 500 Hz is within the range of absorbers. The only time I have had a room with a single big peak it was a cavity next to a fireplace. I put a door over it and it smoothed out. ( about 1K) Have you moved the speakers around a little? It is a bit of an art making a living room into a listening room while maintaining WAF. It is worth the effort as you will learn so much about acoustics, as well as the benefits of WAF.
I can't express how much I hate this book, I spent a year studying this thing about 8 years ago, and I came to the conclusion that it is very poorly written. In order to understand it, you have to already know it.
It's nearly impossible for beginners to grasp it.
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