• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

REW measurement of FIR filters in Roon's convolution engine

Olli

Senior Member
Forum Donor
Joined
Mar 6, 2018
Messages
333
Likes
245
I would like to verify simulated results for REQ that I get in a software called Audiolense with REW.

Is there a way to get REW’s signal playing through Roon (’s convolution engine)?

This is my set up and how I measure:

Set Up:
Mac Mini with Roon – USB – RME ADI-2 Pro FS Channels 1 +2 going into 2 Subs; channels 7+8 via SPDIF into a Benchmark DAC3B into 2 Amps.

Measurement:
Recording: Calibrated Behringer EMC8000 – IMG Stageline MPA 102 – Analog XLR Input ADI-2 PRO FS
Play: Laptop running Windows 10 and Audiolense XO 5.5 – USB – USB Input ADI-2 PRO FS

Audiolense only works in Windows machine, hence the Laptop. I then import the generated filters into Roon’s convolution engine as described here: https://community.roonlabs.com/t/audiolense-convolution-filters-in-roon-resolved-build-298/35603/10
 
1554974477435.png
 
As for me, I export the sweep signal to a .WAV file.
Then configurate REW I/O to use a soundcard that will record but is not connected in RCA out for playback
Then play the WAV in foobar2000 or JRiver (using the convolution file) with the other soundcard I use for playback & 1 second after start the measurement in REW.

REW thinks it records its own signal, but in fact it records the convolved signal.
 
As for me, I export the sweep signal to a .WAV file.
Then configurate REW I/O to use a soundcard that will record but is not connected in RCA out for playback
Then play the WAV in foobar2000 or JRiver (using the convolution file) with the other soundcard I use for playback & 1 second after start the measurement in REW.

REW thinks it records its own signal, but in fact it records the convolved signal.

Thanks. I'll try that.
 
Last edited:
Thanks. I'll try that.

The easiest way to do it is with file that has timming reference signal included. Timing reference is checked by default after you press "Save file" in generator (like shown on the photo @March Audio posted) so it will be included at the beginning of the measurement sweep file.

When doing measurement V5.20 Beta 7 will also by default be waiting for timing reference signal when you choose playback From File.

After you do measurement it is always good idea to go to Controls/Estimate IR delay and press Shift IR. That way you will get IR aligned to zero at time axis and correct phase response.
 
Were would I find this function? There is no menue called Controls in REW 5.20 Beta 8...
 
Last edited:
Got it. Thanks.
 
That worked. Here's a comparison of an Audiolense Multichannel Sub/Mains setup/measurement (Subs MiniDSP SHD, Mains Weiss 202 DAC, both connected to a MiniDSP UDIO-8 - red), a Dirac (MiniDSP SHD) 2 CH setup (blue) and a non REQ'ed measurement (MiniDSP SHD - green). Please note that the Target curves are not identical in Dirac vs Audiolense (need to copy the Audiolense target curve in Dirac when I have some time) and that I could not figure out how to measure L and R channels seperately in REW on short notice.

Mains are TAD CE-1, Subs JL Audio E112, Amp March Audio P252. XO is at 110 Hz (TADs are on top of Subs).

Screenshot_MS190411_ALvsDirac.jpg
 
So Roon can use FIR filters configured externally. If I am using a Roon Endpoint device, I assume those filters will be applied to that device but would be housed in Roon Core. If I have more than one Endpoint device, does Roon allow me to have different filters for each device or does one set of filters apply against all endpoints?

Thank you.
 
So Roon can use FIR filters configured externally. If I am using a Roon Endpoint device, I assume those filters will be applied to that device but would be housed in Roon Core. If I have more than one Endpoint device, does Roon allow me to have different filters for each device or does one set of filters apply against all endpoints?

Thank you.
You can have different filters per endpoint. And it will remember the device specific filter when you switch the endpoint.
 
Back
Top Bottom