Measuring Frequency Response of Nearfield Monitors.

[solo2racr]

Found this Wiki page yesterday and thought it rather informative....Loudspeaker measurement - Wikipedia, the free encyclopedia. I also thought this bit from the page to be relieving....." While the very best modern speakers can produce a frequency response flat to ±1 dB from 40 Hz to 20 kHz in anechoic conditions, measurements at 2 m in a real listening room are generally considered good if they are within ±12 dB"

 

[ecc83]

Found this Wiki page yesterday and thought it rather informative....Loudspeaker measurement - Wikipedia, the free encyclopedia. I also thought this bit from the page to be relieving....." While the very best modern speakers can produce a frequency response flat to ±1 dB from 40 Hz to 20 kHz in anechoic conditions, measurements at 2 m in a real listening room are generally considered good if they are within ±12 dB"

Which is in tune with my earlier point about room EQ.No way you can correct a 12dB dip AND pay the lekky bill!

Dave.

 

[solo2racr]

Agreed. Trying to EQ for room compensation is a futile effort. On the other hand, the point I was making was to compensate for monitor deficiencies or to emulate a home stereo speaker (boosted highs and lows) can be a worthwhile effort.

 

[solo2racr]

I was kinda hoping that someone would measure their monitors from their listening position and post the resulting FR graph, but alas.....

 

[bouldersoundguy]

I was kinda hoping that someone would measure their monitors from their listening position and post the resulting FR graph, but alas.....

Here's a series of measurements I did a few months ago:



The "waterfall" graph is especially interesting:

 

[solo2racr]

Thanks. I'll take some measurements of mine later today. Looks like you are using REW and so will I. I am also working on another pair and the model looks fairly good. Below is the simulation graph. The woofer FRD file I created with 6db/oct smoothing and were measured in their enclosure and in place where they will be used. In other words, it includes the baffle step and room. The FRD file for the tweeter is mfg generated. The graph simulates the baffle step on the tweet but not the room. I should have the tweets in a couple days and will post their FR graph as well.

 

[solo2racr]

I took some measurements from my setup from a number of places within about a foot of where I would normally be listening. All either up/down or forward/back. No left/right. I also scaled it to match yours and did a waterfall of the last one as well. Here is what I have.

 

[solo2racr]

I know....looks pretty crappy. I have been working on it and learning a fair bit in the process. The major dip around 2K was a major brain fart on my account. The tweet polarity was normal were it should have been reversed. DUH! The dip around 100hz is also a phasing problem, mostly (part of it is room). I can sorta clean it up just using the phase switches on the sub amp but, it is limited to 0,90,180 270.

I also finished up the new ones that I posted the XO sim of. Already they are better than what I have been using, which are the ones I posted the FR graph of. Two totally different monitors and you can definitely see the room influence when they are measured. Both have dips and peaks in the same places. Knowing that will help in treating the room better, to the extent that I can (no knocking down walls).

I'll post more FR graphs as I get more dialed in on the best they can do.

 

[solo2racr]

Been working on the system response. Playing with crossover points, phase and a little EQ, you can see it's much better than the previous graph I posted. The dip centered around 300hz is room dimensions (I believe) which I can't really do anything about. Measurements were taken within approx a 1 cu/ft. area centered around where I would listen from. Looks like I could pull down the sub level a bit though.