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8351 calibration advice

eljf, modified 1 Year ago.

8351 calibration advice

Youngling Posts: 11 Join Date: 1/3/11 Recent Posts

Hi there. I just used GLM to calibrate two 8351A. The corrected sound lacks bass.

I remember calibrating the Genelec Small Environment system 5 years ago. The result was similar, lack of bass (even with the sub on that system).

Of course if the bass is cut by the GLM EQ, the speakers can concentrate on the mids and highs more. This typically brings more clarity to mid-range, which contains detail of insturments/voice. However, if the bass is lacking, obviously I will mix in too much bass.

The blog post by Lund says that after GLM EQ, often people find the sound too bright. So he recomends a 3db roll off at 10k. https://www.genelec.com/blog/frequency-response-and-personal-preference

However Lund's advice leaves even more mid-range. It still lacks bass (GLM EQ cuts bass, my original problem), and now Lund's advice cuts highs --> which leaves a very clear mid-range, but the sound is not balanced.

I assumed the GLM will make everything sound better, but the opposite is true: it's better for me with GLM bypassed.

  1. Has anyone had similar experiences?
  2. Here is my graph. Any advice for sound treatment? I have DIY panels all around the room. All Auralex: 2" + 4" (walls) + LENRD bass traps (corners).
  3. My graph has a massive dip at 100 Hz. GLM EQ doesn't seem to have any correction here. This could be the cause of the weak bass. Any advice to flatten this out?

 

 

eljf, modified 1 Year ago.

RE: 8351 calibration advice

Youngling Posts: 11 Join Date: 1/3/11 Recent Posts
graph attached here
manutal, modified 1 Year ago.

RE: 8351 calibration advice

Jedi Knight Posts: 172 Join Date: 4/25/14 Recent Posts

I recommend to try different speaker positions if possible, maybe have the rear of the speakers closer to a wall or a corner of the room. This will boost the lower freqs somewhat.

If theres still not enough bass for your like then I would suggest to get a 7370A sub added to your system.

eljf, modified 1 Year ago.

RE: 8351 calibration advice

Youngling Posts: 11 Join Date: 1/3/11 Recent Posts
 

I recommend to try different speaker positions if possible, maybe have the rear of the speakers closer to a wall or a corner of the room. This will boost the lower freqs somewhat.

If theres still not enough bass for your like then I would suggest to get a 7370A sub added to your system.

Hi Anders,

can you please explain more about what GLM measures and corrects? To me, it seems to measure frequency response at listening position(s), and correct with an EQ.

The phase reading in GLM is for subwoofer alignment only. I do not have any subwoofer, so there is no phase measurement / correction for my 8351A (stereo pair).

Is this correct? So GLM is not measuring/correcting reverb times etc.

kind regards,

ian

manutal, modified 1 Year ago.

RE: 8351 calibration advice

Jedi Knight Posts: 172 Join Date: 4/25/14 Recent Posts

Read the manual ;) https://www.genelec.com/sites/default/files/media/Studio%20monitors/Software/GLM%203/glm_3_system_operating_manual.pdf

GLM AutoCal is a powerful monitoring system calibration algorithm running inside the GLM software
Sweeps are generated by each monitor in a group. Responses are recorded with the GLM measurement microphone into your computer.
The computer analyzes the sweeps and calculates the frequency responses for all monitors and subwoofers, then optimizes level and delay to compensate for differences between monitors, and sets equalization for the individual room responses to remove colorations caused by the room and the location where the monitors have been installed. The end result is to have sound from all monitors arriving at the listening position at the same time, same level, and compensated for the effects of the room acoustics, resulting in very accurate imaging and reliable monitoring.

Yes, Autophase is only for subwoofers.

 

 

eljf, modified 1 Year ago.

RE: 8351 calibration advice

Youngling Posts: 11 Join Date: 1/3/11 Recent Posts
manutal:

Yes, Autophase is only for subwoofers.

 

 

Hi Manutal,

thanks for that. Do you know if GLM system uses IIR or FIR filters?

 

manutal, modified 1 Year ago.

RE: 8351 calibration advice

Jedi Knight Posts: 172 Join Date: 4/25/14 Recent Posts
FIR filters atleast.