Troubleshooting audio reverb in small space

[amrak]

Hi,

I have a small room i use for recording and there is this strange sound that is present in most music.

i have uploaded a very short clip, but you can imagine how this would be annoying. Is this some sort of reverb or reflection ? Im not super versed in audio.

 

[amrak]

it is a B3 at 242Hz right at 20 seconds of this video is when it starts

 

[TLS Guy]

it is a B3 at 242Hz right at 20 seconds of this video is when it starts

I have played that video on my big rig and it plays perfectly, with nothing amiss at all.

Your first post, I have no idea what it is and it just plays back as random noise it seems to me.

I suspect you have got a decoding error or some incompatibility in your system.

I don't know what you mean by recording, but if you are into digital recording then you really have to know what you are doing. You have have said you are not versed in audio, and on the basis of what you have submitted to far, I would have to agree.

 

[highfigh]

The recording level is very low but if you want to find out if whatever you're hearing is in the room, gong or electronics, repeat this outside, away from buildings and large objects with parallel walls.

 

[amrak]

So the consistent bit of noise of fans is not what im talking about. There is 3 distinct humms that take place in the recording, i posted the picture of the bowl because the noise this makes is the exact same.

I am unsure how you are listening to this, but if you cannot hear this sound at each of the hot spots on this graph then maybe your speakers are not able to play this frequency? I speak not to the consistent whiteish metallic noise, but the 3 hummmms you can hear that you are looking at above. These are the rogue noises which are appearing seemingly from nothing. The recording device is set to a very high gain and in this clip if i were typing on the keyboard it would be very loud. So the sound of the fans is very loud, but in the room they are not loud. I pumped the gain so you could hear the hum.

So in my recordings, it is not loud, but it is present if you are listening for it. Which is effectively making the space not usable.

My main question, is this something that could be caused by a room's harmonics, like fan sounds reverberating or something causing normal sounds to clash in such a way. Or would it more likely be something creating that sound particularly, possibly a failing AC/DC converter or some failing capacitors or something.

 

[amrak]

I have played that video on my big rig and it plays perfectly, with nothing amiss at all.

Your first post, I have no idea what it is and it just plays back as random noise it seems to me.

I suspect you have got a decoding error or some incompatibility in your system.

I don't know what you mean by recording, but if you are into digital recording then you really have to know what you are doing. You have have said you are not versed in audio, and on the basis of what you have submitted to far, I would have to agree.

Im saying i can hear this myself in the room. Its the humming noise, not the constant fans, but the 2 distinct and 1 trailing hum that occur in the recording. This was captured using a linear PCM recorder at a very high recording level. Nothing is wrong with the recording, its the sounds in the room that im concerned about.
Say you are recording a podcast and you have this very low volume hummmm, hhuummmmm, hhummmmmmmmmm that takes place all the time. I'm trying to nail down the source of this.

Do you think it is something generating the noise directly, or could it be a combonation of noises from fans clashing in a room that are reflecting in such a way that it generates these hums naturally.

 

[TLS Guy]

Im saying i can hear this myself in the room. Its the humming noise, not the constant fans, but the 2 distinct and 1 trailing hum that occur in the recording. This was captured using a linear PCM recorder at a very high recording level. Nothing is wrong with the recording, its the sounds in the room that im concerned about.
Say you are recording a podcast and you have this very low volume hummmm, hhuummmmm, hhummmmmmmmmm that takes place all the time. I'm trying to nail down the source of this.

Do you think it is something generating the noise directly, or could it be a combonation of noises from fans clashing in a room that are reflecting in such a way that it generates these hums naturally.

I have no idea what to make of this. I really have no clue what you recorded. It is an mp3 file of just nasty noise that varies in the points marked. I suppose you could call it hum, but I have no idea where it is coming from in your reproducing chain. That recording sounds like mainly distortion to me.

On general principles, if it is truly hum you are complaining about, then you likely have a ground loop due to resistances between grounds.

 

[amrak]

I have no idea what to make of this. I really have no clue what you recorded. It is an mp3 file of just nasty noise that varies in the points marked. I suppose you could call it hum, but I have no idea where it is coming from in your reproducing chain. That recording sounds like mainly distortion to me.

On general principles, if it is truly hum you are complaining about, then you likely have a ground loop due to resistances between grounds.

Yes it is a nasty noise - but it is ever present. The ground loop idea, seems probable. Another symptom of this would be like sparking when plugging in plugs? Just small spark, not an arc. The recording has static because im recording with a DR-40X linear pcm recorder at full gain. There is network equipment in the room and fans are running. However if you can get past the hiss/gray/static noise. There is a tone that goes in and out, matched up perfectly with those hot spots on the recorded graph.

So to rule out this being a ground loop, i could use a portable battery and then just plug a speaker into this and see if the tone is still present. If it is, then the ground loop idea is not the answer ?