Thread Rating:
  • 3 Vote(s) - 5 Average
  • 1
  • 2
  • 3
  • 4
  • 5
New loudspeakers & room digital correction service
#81
(30-Aug-2017, 11:26)Hifi_swlon Wrote: I'm also more than happy to attenuate the whole signal to bring everything more in line with an ideal house curve. I don't notice any lack of dynamics personally - far from it the sound is far better. I guess in my setup the boom and L-R mismatch are worse than any negative I'll get from EQ. I've got plenty of room on the amp too so more than happy to run it louder.

Agreed. Initially the -9dB attenuation in signal was confusing : do I lose something ? 
Actually with 64bits processing you don't, -9dB is only 3 bits... 
Still there seems to be a bad feeling about having to set the volume much higher. Our nerd brain says "this signal is weaker than it was before this convolution thing". In the Devialet configurator, I have increased the "volume at start" setting by 9dB which removed the frustration Smile
 Roon Air / convolution HAF / Devialet Expert D400 / Speaker cable DIY "PTT" - Speakers DIY Atohm EURUS 1.0 + DIY active SW 
Reply
#82
Hi Guys,
I recently treated myself to a Umik-1 with a view to generating some curves and sending them off to Thierry so that he can generate some correction files. I have one question: when measuring the sweet spot, one uses the left hand speaker, then the right. I know that the Umik-1 is omnidirectional, but do you aim the mic at the speaker, or straight ahead?
Any other pointers would be greatly appreciated.
TIA,
Alex.
Project Eperience X Pack with Ortofon Rondo Red MC, Oppo BDP 105D, Sonos Connect, QNAP HS251+ NAS, Mutec MC-3+USB, Mac 5K running Roon, iPad Pro 12.9" for remote control. Devialet 440 Pro, Sonus faber Olympica ll, Rupert Neve Designs headphone amp.Denon AH-D5000, Sennheiser HD600 and HD800 with Cardas cable,  Van Den Hul The First Ultimate interconnects, GSP Audio Spatia speaker cable.
South Coast England
Reply
#83
Point the mic between the two speakers, at tweeter height. Check your UMIK is calibrated with the 0_deg file.
The alternative (which I prefer as it led to more robust results in my case) is to use the 90_deg calibration file and point it to the ceiling.
In any case d'ont move the mike between Left and Right measurements at a given spot.
Keep us posted on the results !
 Roon Air / convolution HAF / Devialet Expert D400 / Speaker cable DIY "PTT" - Speakers DIY Atohm EURUS 1.0 + DIY active SW 
Reply
#84
(05-Oct-2017, 06:28)Alec_eiffel Wrote: Point the mic between the two speakers, at tweeter height. Check your UMIK is calibrated with the 0_deg file.
The alternative (which I prefer as it led to more robust results in my case) is to use the 90_deg calibration file and point it to the ceiling.
In any case d'ont move the mike between Left and Right measurements at a given spot.
Keep us posted on the results !

Thanks Alec. I thought the 90° orientation was for 5.1 systems, but if it worked better that way for you, so be it.  What were the differences in measurements? Do others use this method? Obviously, I want to get this right, as I guess different sets of measurements will be charged for.
Project Eperience X Pack with Ortofon Rondo Red MC, Oppo BDP 105D, Sonos Connect, QNAP HS251+ NAS, Mutec MC-3+USB, Mac 5K running Roon, iPad Pro 12.9" for remote control. Devialet 440 Pro, Sonus faber Olympica ll, Rupert Neve Designs headphone amp.Denon AH-D5000, Sennheiser HD600 and HD800 with Cardas cable,  Van Den Hul The First Ultimate interconnects, GSP Audio Spatia speaker cable.
South Coast England
Reply
#85
(05-Oct-2017, 12:49)Axel Wrote:
(05-Oct-2017, 06:28)Alec_eiffel Wrote: Point the mic between the two speakers, at tweeter height. Check your UMIK is calibrated with the 0_deg file.
The alternative (which I prefer as it led to more robust results in my case) is to use the 90_deg calibration file and point it to the ceiling.
In any case d'ont move the mike between Left and Right measurements at a given spot.
Keep us posted on the results !

Thanks Alec. I thought the 90° orientation was for 5.1 systems, but if it worked better that way for you, so be it.  What were the differences in measurements? Do others use this method? Obviously, I want to get this right, as I guess different sets of measurements will be charged for.

For speakers+room correction measurements it is in my view better to use the mike in 90° configuration (pointing to the ceiling).
This is the recommendation from miniDSP for "DiracLive" applications. 
http://support.minidsp.com/customer/en/p...the-umik-1-
We don't want to measure the speaker but what you hear at the listening position coming from everywhere, direct and reverberated sound.

I know that some users are measuring with the mike pointing at the speakers and 0° calibration file, with success.
In this fantastic tutorial on REW (in French sorry) by PDA0, he states that he has tried both techniques, leading to similar results for room correction. So maybe don't bother too much Smile 

One last little thing... the UMIK-1 is clearly not directional until 1KHz (check both calibration files, values are the same until roughly 1Khz). This means that even if you use the wrong calibration file, the room modes will be properly corrected... At 10Khz there is a 3dB diffenrece in calibration though, so if you want your room curve to be precise, use the proper calibration file.
 Roon Air / convolution HAF / Devialet Expert D400 / Speaker cable DIY "PTT" - Speakers DIY Atohm EURUS 1.0 + DIY active SW 
Reply
#86
Hi Axel,

In the field of DSP, I always considered Mitch, the Canadian blogger who has written this small ebook: https://www.amazon.com/Accurate-Sound-Re...curate+dsp which I Highly recommend, as a reference.

Here is what he is writing about measurements:
[img][Image: 220420ScreenShot20171005at145800.png][/img]

I always followed his methodology with a lot of success and consider, as Mitch, that pointing the mic toward the speakers is the best way to do. What is of major importance is to set-up a reflection free zone (move the furniture out of the zone you are measuring).
Reply
#87
Very good book!

I think it is important to measure the room in the configuration you will have for everyday listening, not moving furniture away for the sake of measurements only, and putting them back. I have a small glass table between the sofa and the speakers that is generating a strong reflection way above the -20dB threshold mentioned by Mitch. This is bad and clearly audible, the soundstage is is clearly more crisp if I take the table away. BUT: my wife loves this table, and it's heavy (the table, I mean...). So it stays here, and I ran the measurements with the table. Same with the (heavy) curtains: sound is better when they're shut, but I usually listen to music during the day, so 2 out of 3 curtains are open. I did the measurements with the 2 curtains open. I wish I had a dedicated room!
 Roon Air / convolution HAF / Devialet Expert D400 / Speaker cable DIY "PTT" - Speakers DIY Atohm EURUS 1.0 + DIY active SW 
Reply
#88
(05-Oct-2017, 15:57)Alec_eiffel Wrote: Very good book!

I think it is important to measure the room in the configuration you will have for everyday listening, not moving furniture away for the sake of measurements only, and putting them back. I have a small glass table between the sofa and the speakers that is generating a strong reflection way above the -20dB threshold mentioned by Mitch. This is bad and clearly audible, the soundstage is is clearly more crisp if I take the table away. BUT: my wife loves this table, and it's heavy (the table, I mean...). So it stays here, and I ran the measurements with the table. Same with the (heavy) curtains: sound is better when they're shut, but I usually listen to music during the day, so 2 out of 3 curtains are open. I did the measurements with the 2 curtains open. I wish I had a dedicated room!

Hi Alec_eiffel,

I was quoting Mitch because his recommendations are kind of 'state of the art' in making measurements. You might have your own habits, but he has a considerable track-record in this field. He suggests to make measurements with furniture removed for a reason, which is not to correct the installation for the reflections which are linked to the furniture.

[img][Image: 206360ScreenShot20171005at181946.png][/img]

So you should, if you want to make the measurements as recommended by experienced people, remove the chairs of your listening area as well as the coffee table before making the measurements.

Just my 2c
Reply
#89
(05-Oct-2017, 17:03)SwissBear Wrote: Hi Alec_eiffel,

I was quoting Mitch because his recommendations are kind of 'state of the art' in making measurements. You might have your own habits, but he has a considerable track-record in this field. He suggests to make measurements with furniture removed for a reason, which is not to correct the installation for the reflections which are linked to the furniture.

So you should, if you want to make the measurements as recommended by experienced people, remove the chairs of your listening area as well as the coffee table before making the measurements.

Just my 2c
Your recommendation makes sense clearly. I'll check with Thierry about his view on what is best for "coffee tables and chairs", that are generating reflections in the first 10ms.
PROS for removing furniture in the reflection free zone :
- better segregation direct field VERSUS reflected + reverb field
- better speakers phase measurements  --> better phase correction
CONS
- "spectral" behaviour of early reflections changing overall  tone balance ?
- frequency spectrum of reverberated field wrongly estimated and therefore not properly corrected ?
 Roon Air / convolution HAF / Devialet Expert D400 / Speaker cable DIY "PTT" - Speakers DIY Atohm EURUS 1.0 + DIY active SW 
Reply
#90
Thank you all for your replies. This has given me the knowledge I need to get the measurements done accurately.
Project Eperience X Pack with Ortofon Rondo Red MC, Oppo BDP 105D, Sonos Connect, QNAP HS251+ NAS, Mutec MC-3+USB, Mac 5K running Roon, iPad Pro 12.9" for remote control. Devialet 440 Pro, Sonus faber Olympica ll, Rupert Neve Designs headphone amp.Denon AH-D5000, Sennheiser HD600 and HD800 with Cardas cable,  Van Den Hul The First Ultimate interconnects, GSP Audio Spatia speaker cable.
South Coast England
Reply


Forum Jump:


Users browsing this thread: 2 Guest(s)