• Registered: 2017-11-08
  • Posts: 2

Topic: REW with Multiface II. How to connect the mic preamp?

Dear all,
I currently use REW as well as Holm impulse or SMAART to record sweep or similar impulses from my 4 way active speakers in order to build crossovers and FIR filters with Acourate. Up to now I've used as audio interfaces MOTU or Presonus devices that come with mic pres with phantom power. Unfortunately under Win 10 and thunderbolt 3 adaptors the drivers of the above mentioned hardwares give me annoying stuttering.
Now I would like to know if Multiface II, one of mine audio interface without mic input, also can be used to acquire impulses with REW. How can I connect my mic preamp to Multiface II? How the calibration of the Multiface can be obtained? And finally, how the reference channel on REW can be settled? I have inadequate knowing of Totalmix and Multiface as acquisition device and therefore your help it would be greatly appreciated.
GiAnt

  • ramses
  • DAW Mastermind
  • Offline
  • From: UTC+1
  • Registered: 2012-10-14
  • Posts: 13,401

Re: REW with Multiface II. How to connect the mic preamp?

via analog, adat or spdif ... put the other devices in kind of standalone mode with the required routing and then go.
Or let the other drivers still run / control the interfaces routing, and then use the mic pres of Motu or Presonus and connect them to the RME using analog or digital audio channels as required / possible.

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14

3 Reply by ramses (edited by ramses 2017-11-08 14:18:18)

  • ramses
  • DAW Mastermind
  • Offline
  • From: UTC+1
  • Registered: 2012-10-14
  • Posts: 13,401

Re: REW with Multiface II. How to connect the mic preamp?

This is how I used i.e. an RME UFX recording interface as a preamp on a RME RayDAT.
http://www.tonstudio-forum.de/blog/inde … ME-RayDAT/

Simply do smth similar.

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14
  • Registered: 2017-11-08
  • Posts: 2

Re: REW with Multiface II. How to connect the mic preamp?

Many thanks ramses for your reply.
Yes, connection of the mic preamp is effectively quite intuitive. My issue is actually the proper configuration of REW and corresponding routing of the channels in order to obtain the exact flight time of the the sound from the individual driver to the listening position (i.e. mic). My system, thanks to (((Acourate))), is actually configured with a vertical offset between the centre of the drivers within one sample other than drivers in phase at the crossover frequency. This outstanding precision is obtained thanks to a reference channel whose only difference with the channel capturing the impulse is the time of flight. Unfortunately REW can manage only an audio interface at a time and similarly asio drivers do not allow to manage two interface simultaneously.
With the MOTU 828 I solved in different ways, e.g with an Y cable or using the other channel of the same way looped with the second mic input or via internal routing.
If I connect the motu mic to multiface via adat or spidf I also insert in the system a latency due to the digital conversion and other with respect to the simple analog outputs of the multiface where are connected the individual drivers. My request of help was mainly directed to guys that have already solved this issue of measuring impulses (and therefore the corresponding delays) with REW, or even better with Acourate, using as interface the multiface II.
Hoping that I have been understandable
GiAnt

  • cyrano
  • DAW Mastermind
  • Offline
  • From: Belgium
  • Registered: 2015-04-28
  • Posts: 701

Re: REW with Multiface II. How to connect the mic preamp?

FYI:

http://audiovero.de/en/acourate.php

Reads like black magic to my uneducated eyes...

I mean, what's a "Psychoacoustic frequency response"? Munson curve?

MB Pro - 2 X FireFace 400, FF800 & DigiFace USB
ADAT gear: Korg, Behri, Fostex, Alesis...

cyrano's Website

  • cyrano
  • DAW Mastermind
  • Offline
  • From: Belgium
  • Registered: 2015-04-28
  • Posts: 701

Re: REW with Multiface II. How to connect the mic preamp?

giantquattro wrote:

My issue is actually the proper configuration of REW and corresponding routing of the channels in order to obtain the exact flight time of the the sound from the individual driver to the listening position (i.e. mic).

OK. This part is clear. It's the delay "in air" + converter latency.

My system, thanks to (((Acourate))), is actually configured with a vertical offset between the centre of the drivers within one sample other than drivers in phase at the crossover frequency. This outstanding precision is obtained thanks to a reference channel whose only difference with the channel capturing the impulse is the time of flight.

A vertical offset?

Within one sample?

If I connect the motu mic to multiface via adat or spidf I also insert in the system a latency due to the digital conversion and other with respect to the simple analog outputs of the multiface where are connected the individual drivers.

There is only one A to D conversion. The rest is purely digital. In sync.

I don't know how much added latency there is, but it should be minimal, eg 1 to 4 samples.

My request of help was mainly directed to guys that have already solved this issue of measuring impulses (and therefore the corresponding delays) with REW, or even better with Acourate, using as interface the multiface II.
Hoping that I have been understandable
GiAnt

It's not a problem that worries me on a daily basis big_smile

And I use a FF400, that probably shows different numbers.

If I understand correctly, it's a time correction for the physical distance between the mid, low and high speaker.

I worry more about room reflections big_smile

MB Pro - 2 X FireFace 400, FF800 & DigiFace USB
ADAT gear: Korg, Behri, Fostex, Alesis...

cyrano's Website