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Discussion Starter · #1 ·
Hello:

Sorry, my english is not good, and I use an software.

This is my first post in this forum. Greetings to all members from Spain.
I'm trying to leave my room recording their best to help me with REW. I leave the last measurement waiting if anyone can comment on what looks interesting.
It is a small room: 4.68 (length), 2.78 (broad), 2.00 (High) (in meters)
The measurement is made with a special micro for measurements located about 30 cm away. The band of this measurement is from 70 to 20 KHz.
The goal I have set myself to reach the current state is to leave the room well for Spanish guitar recording. For this reason I have placed the microphone on this measure fairly close to the monitor. By that I capture many harmonics of the source definition and a compromise between the proximity effect and the living environment (in a small room with its modes is always problematic) effect. It is a Quested S7 monitor.
The measurement is made remotely, from other room. I used a PC card RME 9632 and a preamp Lavry Blue.
If you can, you look at the data of minimum phase and impulse response to see how you consider it.

The room is equipped with acoustic resonators made by me, both as membrane and Helmholtz (in total there are 23). The floors is of wood and ceiling too, with half of its surface with mineral wool.

In the band ranging from 90 to 150 Hz there is a clear enhancement. If I place the microphone farther may disappear. Do you think that is problematic?

Thanks!
 

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the microphone should be placed in the listening position (in your case at the point where you do your work digital) the principle response environment is not bad (with the limits of the monitor that does not fall in the low range).
I think that the volume used is a little low, and I do not see nor calibrate the sound card it that of the microphone (assuming you're using a microphone with individual calibration).
there is a fault in the impulse, and as if it had the proper swep.



this is a pulse correct




on the other hand you have an excellent ETC!
 

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Those small peaks ahead of the main peak are nothing to worry about, they are distortion images and are mainly visible because the signal to noise ratio of the measurement is very good. The distortion is mainly 2nd harmonic and well below 1% above 200 Hz.

The room is very well damped and the response very even, well done!
 

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Discussion Starter · #6 ·
Hello giordi60:

Thank you very much for your help.
I calibrated my room at first for recording. That is, preparing the room to the point of microphone placement I chose the frequency response is best.
I will then calibrating monitors since, although it is not the right thing, use the same room to record and mix. I'll make it to record and then calibrate and equalize monitors the situation in the room that is left.

For that reason now place the microphone closer to the monitors, but also do tests on other distances.
I'm glad you find the ETC well.
It seems that the previous peak at t = 0 do not like, is it? Could you explain what is wrong.
Regards!
 

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Discussion Starter · #7 ·
Hello John M.:

Sorry, my english is not good!

I appreciate your comments. Glad to know that you think that the room is well equipped.
I have used acoustic resonators made by me, and a wooden floor and a wooden ceiling with half of mineral wool. Before LF traps bass business, and the truth is that I have not served because absorb high frequencies and do not the same with the bass.
Best regards!
 

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Discussion Starter · #8 ·
Hello giordy 60:
Well, I'll make a new measurement down a notch to avoid distortion. The command you tomorrow. Now jump must sleep in Spain.
Thanks !!
 

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Discussion Starter · #10 ·
Hello:
I back up a new measurement in which I have tried to correct some details that you have told me, and I again raise the issue of the peaks in the pulse before t = 0.
As you see now I used a calibration file for micro ECM8000, and the sound card is calibrated (one RME 9632).
In the first measurement using 96 KHz, but this measurement employment 44.1 KHz.
As for the peaks before t = 0 You can see that now appear two, but before appeared more. After making several measurements rising and falling input levels have never achieved the peaks disappear. What I do is I managed to appear only two when using 44.1 kHz. Which I think is because the SRC delivers less samples per second.
According to the program documentation REW I understand that peaks before t = 0, are caused by distortion of each harmonic, and that is normal, that is, that can not be avoided. In any case, as one told me one of you, it is not something to worry about if the rest is fine.

Thank you
 

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if I can give you my opinion I find all excellent measures, but do not understand the impulse response, but no matter.
I find that the volume at which you generated the sweep is low.
(My opinion)

:T
 
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