Welcome, Guest
Username: Password: Remember me

NOTE: This is a "Community" forum. Please be mindful that community members are here to help as part of a community effort. We therefore appreciate your effort in keeping this forum a happy place!

If you have a specific issue (e.g. hardware, failure) and want help from our support team, please use our tech support portal (Support menu - > Contact Us).
Thanks a lot of your help in making a better community.

TOPIC: REW soundcard calibration: include OpenDRC?

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12730

  • phranky
  • phranky's Avatar
  • Offline
  • Junior Boarder
  • Posts: 25
  • Karma: 0
Hi guys, I recently bought an OpenDRC-AN for music production purposes and set it up running fine putting it between my soundcard (NI Komplete 6) and my monitors (Yamaha HS80M). Now I want to start measuring in Room EQ Wizard (5.01 beta17).

My question is about the soundcard calibration in REW, which is normally done by a loopback cable from the soundcard's output to the measuring input. In my understanding the OpenDRC might have its own sound characteristics because of the A/D and D/A converters, right? Let me know if I'm wrong here already...

My question now is:

1. Should I include the OpenDRC to the loopback measurement for the soundcard calibration (to calibrate the whole signal chain at once), sending the signal from my soundcard into the OpenDRC and from the OpenDRC's Out back to the soundcard's In?
2. Or should I just calibrate the soundcard itself and then discover and equalize the OpenDRC's own characteristics alltogether with my room measurements and room EQs?

I hope you know what I mean :)

Here's a screenshot of a calibration measurement including the OpenDRC (dotted line). The solid line is my crosscheck (as mentioned in the REW help) after implementing the calibration, which looks good with a flatness of max. 0,2dB:

Attachment NiKomplete6OpenDRCKalibrierung.jpg not found



But REW gave me this warning message:



...which I think is caused by the sum of the soundcard's + the OpenDRC's characteristics and thus ignorable - also because my crosscheck validated the measurement itself.

Now I'm not sure, if my chain of thought is reasoned. I just have to know, which of the above mentioned ways is the right one :)
Thank you very much in advance!! Cheers, Phranky

This message has attachments images.
Please log in or register to see it.

Last Edit: 6 years 4 months ago by phranky. Reason: clarity
The administrator has disabled public write access.

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12739

  • john.reekie
  • john.reekie's Avatar
  • Offline
  • Platinum Boarder
  • Posts: 3731
  • Thank you received: 1578
  • Karma: 140
What does it look like if you include just the soundcard?
I am not miniDSP support.

"You must ask the right questions." - Dr. Alfred Lanning's hologram.
-> Have you read the User Manual??
-> Have you drawn and posted a diagram?
-> Have you posted a screenshot?
-> Have you posted your config file?
The administrator has disabled public write access.

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12741

  • phranky
  • phranky's Avatar
  • Offline
  • Junior Boarder
  • Posts: 25
  • Karma: 0
This is just the soundcard's measurement:

Attachment NIKomplete6FeedbackMessung.jpg not found

This message has an attachment image.
Please log in or register to see it.

The administrator has disabled public write access.

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12742

  • john.reekie
  • john.reekie's Avatar
  • Offline
  • Platinum Boarder
  • Posts: 3731
  • Thank you received: 1578
  • Karma: 140
It's kinda hard to read the scale. Is that -0.6 dB at 20 kHz?

For future reference, you can use the REW camera button to generate an image of just the plot ;)
I am not miniDSP support.

"You must ask the right questions." - Dr. Alfred Lanning's hologram.
-> Have you read the User Manual??
-> Have you drawn and posted a diagram?
-> Have you posted a screenshot?
-> Have you posted your config file?
Last Edit: 6 years 4 months ago by john.reekie.
The administrator has disabled public write access.

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12744

  • phranky
  • phranky's Avatar
  • Offline
  • Junior Boarder
  • Posts: 25
  • Karma: 0
Oh sorry, you're right ;) Graphs updated:

Soundcard + OpenDRC. Dotted line: measurement. Sold pink line: crosscheck after calibration:


Soundcard only measurement:


edit: still hard to read. yes it's -0,6 at 22,1 kHz

This message has attachments images.
Please log in or register to see it.

Last Edit: 6 years 4 months ago by phranky.
The administrator has disabled public write access.

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12751

  • phranky
  • phranky's Avatar
  • Offline
  • Junior Boarder
  • Posts: 25
  • Karma: 0
An interposed question / idea:
Is it possible, that the REW soundcard calibration feature is only made to exclude the frequency response of the soundcard's Mic In preamp? In my mind this is the only point of the measurement chain, which has a meaningless influence on the measurement. I mean, if the outputs of the soundcard and OpenDRC themselves have own characteristics / freq.responses, they would be part of the measured result and as such alltogether rectified by the room EQs, right?
Actually my question is just a logical one ^^
The administrator has disabled public write access.

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12794

  • phranky
  • phranky's Avatar
  • Offline
  • Junior Boarder
  • Posts: 25
  • Karma: 0
Any hints here? :)
The administrator has disabled public write access.

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12797

  • curryman
  • curryman's Avatar
  • Offline
  • Platinum Boarder
  • Posts: 792
  • Thank you received: 181
  • Karma: 101
To be honest I am wondering about the measurement including soundcard and openDRC. As far as I can see its 3dB down at around 37Hz. Also the lowpass at high frequencies is a bit extreme if the scale is really 1dB per div.. Are you really sure no filter is activated in the openDRC during this measurement?

In general your thought from your last post is correct. You'd want to correct only your measurement system (soundcard+mic). Everything else should be accounted for in your EQ.

kind regards, Daniel
The administrator has disabled public write access.
The following user(s) said Thank You: phranky

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12803

  • phranky
  • phranky's Avatar
  • Offline
  • Junior Boarder
  • Posts: 25
  • Karma: 0
Yeah I'm sure that there were no filters active on the OpenDRC. Perhaps it's really the sum of all the converter's behaviours.

Anyway, if it's generally the wrong idea to include the OpenDRC in the calibration, I won't further think about that. Thank you very much! :)
The administrator has disabled public write access.

REW soundcard calibration: include OpenDRC? 6 years 4 months ago #12873

  • devteam
  • devteam's Avatar
  • Online
  • Administrator
  • Posts: 8748
  • Thank you received: 1123
  • Karma: 161
If you're 100% sure it's not a measurement mistake (i..e happens to us all the time.. :-) Almost could sound like an impedance issue with your PC + OpenDRC.. just a wild guess.
I really don't think that you'd have an issue.

DevTeam
miniDSP, building a DSP community one board at a time.
The administrator has disabled public write access.
Moderators: devteam