Help with Measuring My Room without Blowing up Speakers

[Touch The Universe]

I'm trying to measure my room. It says to match 75db but something isn't right. The audio is maxed out on my computer and focusrite 2i2 and at max it's 65-70 db and it's very loud. Doing the test at this level nearly blows the sub/speakers. It clips to silent as it sweeps. I have to turn it down by half to get a measurment that is one sweep that isn't broken.

Is there a way to effect volume sensitivity. What am I missing?

Here is the image going at volume level 50dbish. Now that I look at it, I think the sub might be turned up too loud since that part looks at 80db (duh). Will try again and post a video if the problem is still there.

 

[Touch The Universe]

Not sure what's up, I lowered the volume on the sub by 6db (as well as the speakers) and it seems to fix the issue. I lowered the volume by the same amount, so not sure why it is okay now.

Thoughts about the image?

Room is roughly 24 by 12 (variable).

 

[Touch The Universe]

Okay, this time I increased the rokit 5 monitor speakers by 6db each but left the sub level as is. Is this better? Is the goal to have a flat line?

 

[Touch The Universe]

Should I lower my subs a few db?

 

[Touch The Universe]

Krk Rokit Sub 10" lowered by 6db seems to give a flatter response. Is this what I want?

 

[Touch The Universe]

nm

 

[Touch The Universe]

This should be more helpful. Clearly, there is a lot of stuff that needs fixing.

Good news is there seems to be no major phase issues, l and r speakers look identical.

So, how can I start fixing things? How do I use an eq to do so until I can treat my room?

 

[Touch The Universe]

 

[John Mulcahy]

I'm trying to measure my room. It says to match 75db but something isn't right. The audio is maxed out on my computer and focusrite 2i2 and at max it's 65-70 db and it's very loud.

If it's very loud then it isn't 65-70 dB! If you aren't using a USB mic with a calibration file including sensitivity REW has no way to know how to translate the data values from the mic into SPL figures. You tell REW how to do that through the SPL calibration process. Best also read the Check levels process, paying particular attention to the first few sentences:

REW measurements are usually made at a level of about 75 dB SPL. This is not very loud, it is the same level aimed at by most receivers to adjust speaker trims. Using very loud test signals is likely to damage your speakers and your ears. Do not use test signal levels any higher than you would be comfortable listening to for long periods.

 

[Touch The Universe]

I'm using the umik mic with a calibration file. I've attached the collaboration file. The charts I took are around 150 db. Is the collaboration file not working?

 

[John Mulcahy]

The UMIK may not have been selected as the input device and input in your first measurement and there is no input selection in the zoom.mdat file, in both those cases REW can't apply the sensitivity info. The UMIK was correctly selected in the 4.mdat and 5.mdat files you posted so those were actual levels. Note that if you unplug the UMIK while REW is running the input selection will be lost.

You have also loaded the mic calibration file as a soundcard calibration file. That is wrong, and REW gives you a message to tell you so. Clear the soundcard calibration file in the REW soundcard preferences. There is a guide that covers using the UMIK in the downloads area, worth looking at.

 

[Touch The Universe]

Reading the manual now, it says to use an hdmi cable or rca cable? I have my monitors connected use 1/4 and xlr cables into my sub. I don't see this as an option anywhere in the manual. Am I still good to go?

 

[Touch The Universe]

I removed the soundcard calibration file. Hopefully, this looks good. I have the umik selected as the input using Java (should I try ASIO instead?).

I noticed its impossible to get flat with a sub connected, is this normal? I'm much closer to flat without the sub! If the goal is to monitor flat, does it make sense to use the sub in my room? I make edm so the low end is crucial. At the end of the day, I may need to just go by ear. It sounds like this in my room, it sounds like this on pa speakers/club, so I should cut, keep the same, increase etc.

With Subs

Without Subs

Superimposed (with and without)

 

[John Mulcahy]

You have a very wide graph range (150 - 200 dB depending on the graph), so things look much flatter than they are. Use the Limits button at the top right of the graph to set a range of 60 dB - have a look at Matt's video for more on that:

Flat in-room responses do not exist, you may get flattish curves by applying a lot of smoothing or setting a very wide SPL range but every room has peaks and troughs, particularly in the low end. Here is your response with a 60 dB range and minimal smoothing (best for seeing what the low end is doing):


There is a very big peak at 50 Hz, which is probably mostly due to positioning of the sub and/or your listening position. The REW room simulator can help with getting an idea of how different positions will look if your room is rectangular. The sub is also well above the rest of the response so needs bringing more into line by reducing its level. Some gentle downward slope from low frequencies to high is normal for listening position measurements, but yours is more of a mountainside just now

 

[Touch The Universe]

I believe I improved things. I had my setup with the speakers facing the side, but, with a lot of effort, moved my setup so the speakers are facing the length of the room and an interesting thing happened. It flattened the bass. There are still quite a few things to improve, but I'm making progress. I can still ski on the thing but the speed down would atleast be manageble. Anything else I can try, besides acoustic treatment? Adjusting the sub levels improved the flatness to a small degree only.

 

[Touch The Universe]

Managed to smoothen things out a bit afterall adjusting the subs, now, no parts deviate from midline by 10 or so, much better than the 30 db I was at previously!

 

[John Mulcahy]

Looking a lot better! A parametric filter would tackle that 72 Hz peak without much drama. Those ripples at the top end suggest you had both speakers playing and they are at slightly different distances from the mic position. You'll see a smoother top end measuring each speaker on its own.

 

[Touch The Universe]

You are right! Cool that you can notice that This looks good to my untrained eye with no room treatment. I'm going to start treating my room, any recommendations? I don't want to break the bank and it looks like it might not need too much work. I'm going to move soon so the stuff needs to be portable and reusable.

 

[John Mulcahy]

For treatment best looking online at the options, GIK Acoustics (for example) have explanatory material alongside their offerings that should help figure out what might help.

 

[Touch The Universe]

These are cool. Any others top of mind?

 

[John Mulcahy]

Not really, I'm no expert in treatment options.