Small Home Drum Studio

Yep. That's exactly what I was thinking... - Stuart -

Hi guys, I think i've finally got this to work. You can download the REW test from here. Thanks for all your help guys. Let me know your thoughts on the test

Soundman2020 wrote:

Yep. That's exactly what I was thinking...

Does the new test seemed to have fixed this Stuart? It looks like it has to me. You can download the test from here if you missed it in the last post Thanks Alastair

Hey, Alistair, sorry about that! Missed the update... Well, the latest graph certainly shows a major improvement in that huge mode that you had at around 40 Hz, and a more consistent overall decay, but there are still some issues that you could probably improve, if you wanted to. (For example, there's a new mode that appeared at about 90 Hz. ) But the basic issue is that the two curves do not match. The "original" and "finished" curves look like they are from different rooms, not the same room before and after treatment. So something is not right. Did you have the speaker and mic set up in the exact same location for both tests? Did you use the exact same mic for both tests? Did you calibrate REW correctly, with the sound level meter? Can you explain roughly what you did to the room, and also post some photos of how you treated it? I looked back over the thread, and you had several plans for various things, but I'm not sure which ones you actually went with. But the key point is: how does the room SOUND now? - Stuart -

Soundman2020 wrote:

but there are still some issues that you could probably improve, if you wanted to. (For example, there's a new mode that appeared at about 90 Hz. )

I would be very interested in fixing them if I can.

Soundman2020 wrote:

But the basic issue is that the two curves do not match. The "original" and "finished" curves look like they are from different rooms, not the same room before and after treatment. So something is not right. Did you have the speaker and mic set up in the exact same location for both tests? Did you use the exact same mic for both tests? Did you calibrate REW correctly, with the sound level meter?

The reason the original and finished curves do not match are because they are using to different interfaces. The original interface broke somehow while doing the new tests so I couldn't use the same interface. I then used a different interface to do the new tests but had problems with the calibration because of the feedback loop. The speakers and mic were setup exactly the same way throughout and REW was calibrated correctly as far as i'm aware

Soundman2020 wrote:

Can you explain roughly what you did to the room, and also post some photos of how you treated it? I looked back over the thread, and you had several plans for various things, but I'm not sure which ones you actually went with.

The walls were covered in 4" thick insulation with a 1" gap behind. I then put insulation angled at 45 degrees covering the wall to ceiling corners. I just made these as big as I could for each section. The corners were then filled with Superchunks 62cm across the front face. Then I hung a 1.5x1.5 cloud from the ceiling which was made from a 18mm piece of MDF glued to a 18mm piece of plywood, with 2" of insulation above and below the hard back. I also created a air tight wall section ready to make into a slot wall at some point. I've attached some pictures of the finished room

Soundman2020 wrote:

But the key point is: how does the room SOUND now?

To my ears the room does sound a lot better. In terms of drum sounds, the snare has a lot less ring and there seems to be a lot less flutter echo on the toms. The bass also seems a lot more manageable. Before it was very over powering. I'll do a recording and upload in tomorrow so you can hopefully hear the difference with the kit sound Thanks Alastair

The reason the original and finished curves do not match are because they are using to different interfaces.

Tat should not make any difference at all: you did the calibration for both of them, and both the calibration files are in use, so any difference between the interfaces are irrelevant, since REW is correcting for them. And in any case, the difference are much, much bigger than can be explained by switching interfaces.

The speakers and mic were setup exactly the same way throughout and REW was calibrated correctly as far as i'm aware

Did you measure the exact positions of both speakers and the mic after the first test, accurate to 1/4", and make sure that it was exactly the same for the second test? It is critical to have the mic in the precise same location for every test: If not, then you can't compare the graphs. Each graph is still valid, for that position of the mic, but they are not comparable, since they are showing different locations. I think that's what happened here. Here's a comparison of the 2 SPL graphs so you can see the differences: And here are the two waterfall plots: As you can see, there are major differences, not explainable only by the treatment you did. The latest graphs look a lot better than the originals, but it just isn't possible to compare them directly, as they are so different.

I'll do a recording and upload in tomorrow so you can hopefully hear the difference with the kit sound

That would be great! - Stuart -

Soundman2020 wrote:

That should not make any difference at all: you did the calibration for both of them, and both the calibration files are in use, so any difference between the interfaces are irrelevant, since REW is correcting for them. And in any case, the difference are much, much bigger than can be explained by switching interfaces.

Ah ok I understand now. However there are several different REW files one of which has a different mic position to the other two tests. To make sure we're looking at the same test i'll link to them again below. If these two tests still don't match up then I don't really know what happened. I was very careful to make sure the mic and speakers were in exactly the same position each time. This test was using the wrongly calibrated interface that had the feedback loop. It was however using the same mic and speaker position as the correctly calibrated test below This test uses the same mic and speaker positioning as the above test and also has the correct calibration Hopefully this clears everything up. Apologies for all the confusion

I'll do a recording and upload in tomorrow so you can hopefully hear the difference with the kit sound

Here is the new and original drum kit samples for you to compare as well Original Drum Kit Sample New Drum Kit Sample Thanks again Stuart, sorry to have mucked you about a bit with all the confusing files. I really appreciate your help Thanks Alastair

Well, there sure is a major improvement evident in that final REW test, as compared to the original! The biggest remaining issue is the ringing at 90 Hz. That is possibly related to the length of the room, perhaps something going on between the windows and the far wall. It might be worth treating that, if it is annoying. It's sort of around the fundamental of a kick drum, depending on how it is tuned. I guess the big question here is: how does the room sound now? Are you happy with it, or is there some aspect that bothers you? - Stuart -