Help me to find Better Recording after DIY acoustic treatment

CatMalone

New member
Hello,

I record audio tutorial at my home studio and recently I moved to a new place and did DIY acoustic treatment to reduce the room reflections.
BTW I have no connection with music industry I just record audio tutorial.


I've done two sample recordings (each approx. 1 min long):
one "without acoustic treatment" and
the other one with acoustic treatment.

I listened to both the recordings but couldn't find much difference, may be, because I have multimedia headset so would you please help me to find out which recording sounds better. DAW is Reaper and I attached the RAW recordings:


FYI: First 10 seconds are room tone then I started speaking...


Recording without acoustic treatment
Dropbox - Without_acoustic.mp3 - Simplify your life



Recording with acoustic treatment
Dropbox - 3rd-with-acoustic.mp3 - Simplify your life

Please Note: While doing this recording at 5:30am some neighbors woke up and made some noise but I finished it fast so I was slightly close to the mic than the earlier recording thats why it sounds little loud otherwise I did both the recording at the same place, sitting at the the position and with the same mic.


1. Is file "with acoustic treatment" sound somewhat better?

2. Is sound muffled?



UPDATE Jan 20

I made many changes in my DIY acoustic treatment after getting your feedback and I hope it will work better than earlier:

Dropbox - jan 20_1st_take.mp3 - Simplify your life

This is a raw file.

I request our fellow members [MENTION=196982]keith.rogers[/MENTION] [MENTION=89013]TalismanRich[/MENTION] [MENTION=39487]mjbphotos[/MENTION] kindly have a look at it :)

Thanks in advance!
 
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I hear noticeably less echo in the "with treatment" version. It's going in the right direction and will be easier to listen to. I am curious what your DIY treatment is.

There's a fair amount of background noise that you might try to address.
 
I agree with Keith that 'with treatment' is better, less room reflections. ALso, for voice work like this, recording at the volume/closeness of your 'with treatment' sample will result in less noise being noticed between phrases.
 
Hi Cat. Good to see you're back.

The acoustic treatment definitely sounds better.

I don't hear it being muffled at all. The one with acoustic treatment also sounds a bit quieter in the initial part. I could hear your breathing and some of what sounded like you shuffling paper. If you're having difficulty hearing the difference, a good set of headphones may help. The typical multimedia headsets aren't necessarily designed to let you hear that level of detail.

Things have improved immensely since your initial posts this past summer.
 
I hear noticeably less echo in the "with treatment" version. It's going in the right direction and will be easier to listen to. I am curious what your DIY treatment is.

There's a fair amount of background noise that you might try to address.

Alright :)

1. Sure, let me share what I did under DIY treatment:

At my left, I hung a small size woolen bedsheet (but it was pretty thin) on the wall
At my back, I had a folded quilt, on top of it, a pillow and those all were covered with a bedsheet and then I put a think blanket on it followed by my left side.

For mic: rather keeping anything at back, I directly covered the "back" of the mic with 2 beanies (attached them with a friendship band)

I know it wasn't good DIY treatment but it was big leap for me to do this kind of stuff because I never wanted to do this but I pushed myself to do this uncomfortable thing.

Fortunately, it sounds bit better than without treatment.


2. I'd do something to fix the noise

and will also do something more to improve the acoustic treatment by hanging blanket etc...

I'd share my result with you guys.
 
I agree with Keith that 'with treatment' is better, less room reflections. ALso, for voice work like this, recording at the volume/closeness of your 'with treatment' sample will result in less noise being noticed between phrases.

Thank you for reviewing, I'm grateful to you.
 
Hi Cat. Good to see you're back.

The acoustic treatment definitely sounds better.

I don't hear it being muffled at all. The one with acoustic treatment also sounds a bit quieter in the initial part. I could hear your breathing and some of what sounded like you shuffling paper. If you're having difficulty hearing the difference, a good set of headphones may help. The typical multimedia headsets aren't necessarily designed to let you hear that level of detail.

Things have improved immensely since your initial posts this past summer.

Hi TalismanRich,

Likewise :)
Hope you're doing good.

I remember your suggestion about Reaper, in last summer you recommended me to try Reaper and at that time Reaper's interface and learning curve intimidated me because I was comfortable with audacity as I was using it for quite good time. BUT I taken your suggestion seriously at that time and started using and learning Reaper.

2. Yeah, I know but due to some reasons I'm not getting studio monitor headset, there are a few other priorities.

3. Thank you for the kind word. I don't have a formal education in music or sound so I consider myself a noob when it comes to audio but I've insatiable appetite to learn and get better in it (atleast to that extend so that I do good recording) but still sometimes LUFS, RMS, TruePeak, NosieFloor confuse me (even though I learned little bit about them) because slightly change in gain and mic position etc.. while recording, that change all these figures, anyways :)

Thanks for reviewing.

I'm grateful to you :)
 
UPDATE Jan 20

I made many changes in my DIY acoustic treatment after getting your feedback and I hope it will work better than earlier:

Dropbox - jan 20_1st_take.mp3 - Simplify your life

This is a raw file.

I request our fellow members [MENTION=196982]keith.rogers[/MENTION] [MENTION=89013]TalismanRich[/MENTION] [MENTION=39487]mjbphotos[/MENTION] kindly have a look at it :)

Thanks in advance!
 
It sounds like you have eliminated much of the room echo from your sound.

What I still hear is a fairly consistent whine in the noise floor. You can hear it faintly through the whole track. Its about 40 dB or so below your normal voice. I've isolated and amplified it so that you can hear what it sounds like. I'm not sure where it is coming from. It could be due to a lack of shielding. What mic are you using?

If you can't find the source, you can eliminate it using the ReaFIR plugin in subtract mode. Set your cursor in the silence section and read the noise for a couple of seconds. That will drop the background noise.
 

Attachments

  • jan 20_1st_take initial silence.mp3
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The spectrum of that noise has the fingerprint to me of a cheap (sorry!) 16 bit USB converter. The spike at 1kHz and the 'mess' further up the frequency scale gives it away. The 100Hz hum blip is from an active device of some sort with poor 50Hz mains filtering on its supply rails but is probably too low to be a problem.

These poor quality converters are usually found in small mixers but I suppose some internal soundcards could be to blame? That would tend to explain the hum. You can eleiminate to some degree the audibility of the whine by changing Windows recording levels.

Papers shuffled? !! Never give a reader a bundle of scripts! Put the words on large cards (called "idiot boards" over here) or at least pin individual pages up where they need not be touched.

Dave.
 

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The spectrum of that noise has the fingerprint to me of a cheap (sorry!) 16 bit USB converter.

No worries, I understand you're trying to help me and I'm happy with that and looking forward for suggestions.


The spike at 1kHz and the 'mess' further up the frequency scale gives it away. The 100Hz hum blip is from an active device of some sort with poor 50Hz mains filtering on its supply rails but is probably too low to be a problem.

These poor quality converters are usually found in small mixers but I suppose some internal soundcards could be to blame? That would tend to explain the hum. You can eleiminate to some degree the audibility of the whine by changing Windows recording levels.

Papers shuffled? !! Never give a reader a bundle of scripts! Put the words on large cards (called "idiot boards" over here) or at least pin individual pages up where they need not be touched.

Dave.

I answered to your questions below (and also tried what you suggested):




It sounds like you have eliminated much of the room echo from your sound.

What I still hear is a fairly consistent whine in the noise floor. You can hear it faintly through the whole track. Its about 40 dB or so below your normal voice. I've isolated and amplified it so that you can hear what it sounds like. I'm not sure where it is coming from. It could be due to a lack of shielding. What mic are you using?

If you can't find the source, you can eliminate it using the ReaFIR plugin in subtract mode. Set your cursor in the silence section and read the noise for a couple of seconds. That will drop the background noise.

Yesterday before posting when I listened to the recording, I also noticed the noise BUT as I never recorded in this kind of quite environment before so I had an illusion, I thought may be this is natural, this much noise happens in everyone's recording but at the same time I also had a doubt so I posted here because I was sure you guys would guide me in a right direction.

1. Last whole night, I tried to figure out, the noise source but I couldn't, I turned off my speakers. Looked at the whole setup and process precisely, I spent whole night switching off various devices and appliances and tested noise floor but nothing made any difference.


Let me share what else I did:

2. Windows Fix - I also reduced the recording level in windows, I came across this fix at YT, that sound engineer (YouTube) had a same issue so I reduced the recording level:
cropped.png
but it didn't work, the consistent whine in the noise floor is still there.


FYI: Gear: BTW I use MXL 770 mic + Scarlett Solo 2nd gen, having good quality XLR cable + Windows 10. The only thing which I changed is:


3. In winters, it is a pin drop silence at night time so I work at night rather than day time. Its massively quite than the day time.

- On top of it, I used to record on desktop PC but desktop has fan(s) which makes noise so to have better recording quality I switched to small fanless laptop :

Now I record at freshly installed windows laptop and it has only a few apps (rest all preloaded apps I uninstalled):
- Focusrite drivers
- Reaper
- Audacity
that's it...

Plus, after doing DIY acoustic treatment I set the gain at 65% whereas earlier it I had to set at 75% which I think should help to reduce the noise...
but not sure why there is a whine in the noise floor and How to eliminate that?


4. In previous post you said you heard shuffling paper noise, actually there are no papers around me when I record. The noise which you heard it's actually my vibration, as I'm sitting close to the mic (my mouth is approx, 2" away), as soon as I breath (inhale, exhale) mic picks up and also picks up sound of my mouth, even when I move my tongue, may be it also picks up saliva's sound. I myself noticed these things.

I stopped using pop filter and sit close to the mic (to have strong signal to noise ratio), I keep mic in front of my left eye so its not directly in front of my mouth so no plosives. My mouth direction is towards monitor so all air goes in other direction. I learnt this technique from a sound engineer in a paid course.


Lastly in my recent testing, I found when I record my room's tone (between 3AM to 5AM) the noise floor is always: -54db (at that time my distance from mic was 5" to 6")
and when I went close to my mic, even without speaking the noise floor floats between : -48db to -42db
It could be because noise of my breath, mouth sound or saliva's sound.


5. I tried to record by enabling ReaFIR plugin in subtract mode, I'm afraid, it sounds bad I could hear that in headset so I didn't share that in today's post.

I'm little frustrated :) because of endless night's work of testing and eliminating noise but at the same time I didn't give up, I'm also happy and grateful to you and other members who are at my back to help me.

I think may be I'm missing something but there must be a solution.

At least in winters I want to take some advantage and finish some work so :)

Is there any way to figure out step by step what is causing whine in the noise floor, is there any software which help to detect the problem or so?

 
Cat,

Don't use ReaFIR during recording. Use it post recording, just like you used the noise reduction in Audacity. That way you can play with the noise profile, and the FFT size to see what works. Usually the standard 4096 works pretty well. If you hear artifacts, just removed the plugin and then add it back and use different settings.

Below is the Jan 20 1st take file processed through ReaFIR.


Does the laptop have a hard drive? How far away is it from the mic? I've heard my hard drive in recordings before. You might try cranking up the recording level, and aiming the mic at various points to determine if it is indeed internal noise vs external noise. The Scarlett should be a fairly quiet interface. I haven't used the 770, so I can't comment on that one.
 

Attachments

  • Jan 20 1st Take with ReaFIR .mp3
    4.3 MB · Views: 33
The Solo cannot be a 16 bit device unless Focusrite are telling some big porkies about its dynamic range!

I could therefore be wrong about the reason for the 'whine', which, BTW cannot be removed by the reduction in rec' gain, merely pushed down into the noise floor where 'room' and other noises masks it. I suggest you do a 'silent' recording on the Solo. Nothing plugged in or out except the USB cable and keep the PC as far away as possible. Run for 20 seconds or so and post the result (320k best MP3 is handiest for me).
If that prodedure show the hash, ask Frites!

Dave.
 
Cat,

Don't use ReaFIR during recording. Use it post recording, just like you used the noise reduction in Audacity. That way you can play with the noise profile, and the FFT size to see what works. Usually the standard 4096 works pretty well. If you hear artifacts, just removed the plugin and then add it back and use different settings.

Below is the Jan 20 1st take file processed through ReaFIR.
Thanks, I'd remember that.
BTW personally, I'd prefer to remove the noise source because winters are going on and there is a pin drop silence at night, without the interference of ambient noise which comes from outside so this is a golden moment to figure out what cause noise and eliminate it. I am happy again after trying your this suggestion I learnt a lot.



Does the laptop have a hard drive? How far away is it from the mic? I've heard my hard drive in recordings before. You might try cranking up the recording level, and aiming the mic at various points to determine if it is indeed internal noise vs external noise. The Scarlett should be a fairly quiet interface. I haven't used the 770, so I can't comment on that one.
1. No, laptop doesn't have regular hard disk, it has Flash drive and it makes no noise as you might already know that inside flash drive there is nothing to revolve. BTW I keep mic around 6" away from it.



I've heard my hard drive in recordings before. You might try cranking up the recording level, and aiming the mic at various points to determine if it is indeed internal noise vs external noise. The Scarlett should be a fairly quiet interface. I haven't used the 770, so I can't comment on that one.

2. I tried your this suggestion and taken Massive action, I'm happy now as it was very good experience :).

The whole night I kept removing a device or a gadget which was either on my desk or around my desk (I unplugged them, detached them and dumped all of them in the other corner of the room)
and I removed each device one by one and simultaneously I was monitoring through headphones to notice when the whine in the noise floor goes away.

And After removing every single device I also recorded for almost 10 seconds 'the room tone' to keep track of what works and whats not!

When I listened to all the recordings I found all of them had whine in the noise except the twelfth no. track but the matter of the fact is after twelfth the next tracks I recorded, they had noise. They were recorded in the same situation, nothing was changed, in fact I removed more devices.

I compressed the Reaper project and attached it, would you please :) have a look at it, all the tracks are just a few seconds long.

I also named many tracks by the name of devices which I removed while recording so that we can track what works... for ex:

on Track 12
I removed small gadgets+removed router+without monitor+removed 2nd monitor+removed kvm+100%rec level win

This is Reaper project file name: Jan-22-testing.rpp

Dropbox - Jan-22-Removed-Devices-one-by-one.zip - Simplify your life

Note: Please download as a zip from dropbox and then extract it on your PC/Mac because it's complete Reaper project and I just noticed dropbox is silly because its showing .zip as a folder and showing all its files to download individually which I think in context of Reaper is wrong way.



Thank you so much :)
 
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The Solo cannot be a 16 bit device unless Focusrite are telling some big porkies about its dynamic range!

I could therefore be wrong about the reason for the 'whine', which, BTW cannot be removed by the reduction in rec' gain, merely pushed down into the noise floor where 'room' and other noises masks it. I suggest you do a 'silent' recording on the Solo. Nothing plugged in or out except the USB cable and keep the PC as far away as possible. Run for 20 seconds or so and post the result (320k best MP3 is handiest for me).
If that prodedure show the hash, ask Frites!


Dave.


>I suggest you do a 'silent' recording on the Solo. Nothing plugged in or out except the USB cable and keep the PC as far away as possible.
>Run for 20 seconds or so and post the result (320k best MP3 is handiest for me). If that prodedure show the hash, ask Frites!


Dave please clear this, as you suggested to do silent recording (and I'm more than happy to do that):

1. Should I unplug the mic or mic should remain plugged in?
2. Do I also enable the Solo button in Reaper while recording?

As soon as I get your reply, I'd do the recording and share the result with you :)
 
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>I suggest you do a 'silent' recording on the Solo. Nothing plugged in or out except the USB cable and keep the PC as far away as possible.
>Run for 20 seconds or so and post the result (320k best MP3 is handiest for me). If that prodedure show the hash, ask Frites!


Dave please clear this, as you suggested to do silent recording (and I'm more than happy to do that):

1. Should I unplug the mic or mic should remain plugged in?
2. Do I also enable the Solo button in Reaper while recording?

As soon as I get your reply, I'd do the recording and share the result with you :)

Have nothing plugged into the Solo but leave the mic gain set to approximately where you usually have it but that is not critical.

Yes, you need the Solo set as the input device in Reaper.

Dave.
 
Have nothing plugged into the Solo but leave the mic gain set to approximately where you usually have it but that is not critical.

Yes, you need the Solo set as the input device in Reaper.

Dave.


Dave,

I did exactly what you said. I unplugged the mic and there was nothing plugged into audio interface except the USB cable which is attached to computer.
In fact I tried my best to make things easier by doing 2 recordings:

1. First recording I did at Laptop (laptop is completely silent because it has no fan and also it has flash hard disk which makes no noise. It was approx. 4.5" away from interface)

2. Second recording I did at Desktop (desktop was about 7" away from audio interface, I could have placed it a few more inches away but sorry I forgot. I guess may be it doesn't make any difference because mic wasn't connected to interface)

and I also recorded my screen and created a video so that you can see what I did or may be you want to see Reaper's master meter when I did the recording, may be it's helpful to fix the issue.

The gain was set at: 65% (its my current gain these days)
I did both the recording at Solo mode.


1. First recording I did at Laptop:

Audio 320kbps: Dropbox - recorded-at-Laptop.mp3 - Simplify your life
Screencast (video): Dropbox - recorded_at_Laptop.mp4 - Simplify your life



2. Second recording I did at Desktop:

Audio 320kbps: Dropbox - recorded-at-desktop.mp3 - Simplify your life
Screencast (video): Dropbox - Recorded-at-desktop.mp4 - Simplify your life

Note: If you play the video at dropbox then select HD option (720p) or better download it because its full HD 1080p video whereas dropbox only streams it at 720p


If you watch the video you may also notice that Laptop and Desktop both showed slight variation in noise floor (in the Master Mixer in Reaper), not sure why.

If I made any mistake please do let me know I'll happy to do it again.

Thank you so much.
 
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I listened to the ZIP file, and definitely #12 is the one! There's no whine to it, just lower frequency room noise. That would suggest that the small gadgets you removed may be the issue. What were those gadgets?

Also using the spectrum data that Dave provided, I tried using a deep notch filter to see which band the noise was in. It appears that the peaks right around 1700Hz are the offending ones. I put a deep but narrow EQ filter at that point and it got rid of the whine.


As for the samples without the mic plugged in, they are all basically silent. Noise levels were in the -75dB range with no discernible whine or other sounds. That indicates that you're probably inducing the noise into the microphone itself. Since removing the gadgets also removed the noise, then unless those gadgets are making an audible whine, then they are somehow introducing noise.

I hope this info is helpful.
 

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I listened to the ZIP file, and definitely #12 is the one! There's no whine to it, just lower frequency room noise. That would suggest that the small gadgets you removed may be the issue. What were those gadgets?

Also using the spectrum data that Dave provided, I tried using a deep notch filter to see which band the noise was in. It appears that the peaks right around 1700Hz are the offending ones. I put a deep but narrow EQ filter at that point and it got rid of the whine.


As for the samples without the mic plugged in, they are all basically silent. Noise levels were in the -75dB range with no discernible whine or other sounds. That indicates that you're probably inducing the noise into the microphone itself. Since removing the gadgets also removed the noise, then unless those gadgets are making an audible whine, then they are somehow introducing noise.

I hope this info is helpful.

Yes it helps :)

1. Firstly thank you from the bottom of my heart :) for listening to the zip and trying the fix and also sharing screenshot of EQ filter, its awesome :)


>Also using the spectrum data that Dave provided, I tried using a deep notch filter to see which band the noise was in. It appears that the peaks right around 1700Hz are the offending ones. I put a deep but narrow EQ filter at that point and it got rid of the whine.
I have really no words to say you thanks, you taken my stress away. At least I've an EQ setting as a backup. I'd remember your favor.


> That would suggest that the small gadgets you removed may be the issue.
2. Yes, the small gadgets removed the noise and afterwards I recorded the twelfth track But as I mentioned to you in my last post, and you also might noticed that, immediately from the thirteenth track, the whine in the noise came back.

But After getting your confirmation about my recent reply which I made to Dave. Now I do understand that, I need to test this at my end because something is causing the issue here while recording and the audio interface is 100% working fine.




>What were those gadgets?
These were:
Multimedia Speakers on my desk

Under my desk:
there were old speakers
a pair of old headphones
2 extension cords
phone charging brick
In fact, I also removed a bulb, a pair of alkaline batteries, ear buds which was laying around (this may not cause any issue but I removed em)
I also unplugged laptop from extension cord and gave it a direct power supply from the wall.





Q1. Is it possible that this kind of issue caused by an XLR cable? Should I consider buying a new one?


>As for the samples without the mic plugged in, they are all basically silent. Noise levels were in the -75dB range with no discernible whine or other sounds. That indicates that you're probably inducing the noise into the microphone itself. Since removing the gadgets also removed the noise, then unless those gadgets are making an audible whine, then they are somehow introducing noise.


Q2. The last two sentences which I marked bold, I'm afraid I couldn't understand, would you please elaborate them?


Thank you once again :)
 
Attached is the spectrum of the 'silent' Solo and for comparison that of my Behringer 204HD (at min gain) with nothing plugged in.

The hum on the Solo and its spray of harmonics confirms to some degree a suspicion I have long held about these very basic (aka cheap!) one mic input interfaces? They are not built to the same standard as products further up the price range.

I agree that the hum level is well down but actually gives a noise floor of only -76dB fs peak whereas the 204HD manages -93dBfs peak. I would be rather disappointed to have bought the Solo!

Of course, these tests should be done with properly terminated, 150 Ohm, shielded XLR in place but even so, the picture is not a pretty one.

The good news is, the AI is NOT the source of the whine. Good luck tracking it down! I have a house to prepare for a visitor so will be no help until next Sunday...Sorry.

Dave.
 

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