# First REW set-up help. dBx rta-m+Fiio usb dac



## bzhei (Nov 12, 2013)

Hi guys,

New to REW. 

I just want to ask for the expert opinion if what I have is useable for a beginner's REW set-up. My basic application for the REW is setting up my listening room acoustics as well as the family's home theater system.

Here's what I have right now:

1.) MSi laptop with RealTek HD soundcard
2.) dBx rta-M measurement mic (planning to calibrate using cal file found here in the forum)
3.) Shure X2U xlr to usb converter
4.) FiiO E10 usb dac/headphone amp with line-out
5.) Yamaha 5.1 receiver/tuner/amp
6.) AudioControl SA3050 stand alone rta and SPL meter with calibrated CM-10 microphone (calibrated by audiocontrol themselves)

What I did was the ff (on the windows xp sounds and audio devices control panel):

Recording: dbx rta-m mic ----> Shure X2U ----> usb of MSi laptop (recording set-up was set to Shure) 
Playback: FiiO E10 usb dac ---->MIT Matrix 6 RCA with 1/8 jack adapter ----> Yamaha 5.1 receiver ----> DIY Focal/Vifa bookshelf

My first question is that can I rely on the FiiO E10 as the external soundcard? It has the WM8740 dac chip and a line-out that bypasses the headphone amp section.

Secondly, is there a need (or a way) to calibrate the usb dac or more importantly 'Sync' the Fiio with the dbx mic?

I'm unsure if there would be issues with 'timing' since they are separate I/O devices using different usb ports on the laptop. Quite different than using an external usb sound card with integrated I/O ports

Thanks in advance.


----------



## Phillips (Aug 12, 2011)

bzhei said:


> Hi guys,
> 
> New to REW.
> 
> ...


First of all what are your intentions e.g use EQ etc?

You talk about calibration of the dac and Sync Fiio but going to use a generic mic calibration file. You need to either get the DBX calibrated (cross - spectrum) or buy a calibrated mic for things to be accurate, but if intentions are just to see what the room is doing, that's fine.

Sorry don't sure about the rest.


----------



## bzhei (Nov 12, 2013)

Hi Phillips,

My intention is what you latter mentioned, just to see what the room is doing, but I do plan to use that data to check changes in the room response when I add acoustic treatment to the room. Will it still be helpful even with a generic cal file?

I'm from Asia and can't seem to have the dBx calibrated locally.

However, I have this AudioControl SA3050 stand-alone RTA which I use in my car audio shop. The kit includes this CM10 calibrated microphone. The CM10 mic is calibrated by Audiocontrol when we purchased it and had it shipped here. But am I right into thinking that their calibration is for their own unit? Can't I use it for the REW instead of the dbx unit? Would be great to know as it would keep my cost down.

Thanks


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

bzhei said:


> However, I have this AudioControl SA3050 stand-alone RTA which I use in my car audio shop. The kit includes this CM10 calibrated microphone. The CM10 mic is calibrated by Audiocontrol when we purchased it and had it shipped here. *But am I right into thinking that their calibration is for their own unit?*


That is correct - see here for relevant information.

I think you’d have better luck with the dbx mic and the generic calibration file available on this Forum– you should be able to do a search and find it. Since you seem to be mainly interested in seeing the effects of acoustic treatments, you don’t really need dead-on accuracy. That’s really only necessary if you intend to apply manual equalization – obviously you wouldn’t want to equalize based on anything but a perfectly accurate graph.

Regards, 
Wayne


----------



## bzhei (Nov 12, 2013)

Thanks Wayne,

Very helpful link. 

After some digging in the forums, I decided to make a purchase in the next week or so for a new rig to assure my measurements are reliable.

I might go for Tascam US-122mk2 which I can get locally but still thinking about the mic.

Anyway, I talked to our Audiocontrol distributor and they said they can supply me with the new microphone Audiocontrol has to offer, the CM125 microphone kit.

Their kit comes with a USB key that has a FRD calibration file. Can this be used with REW?

Reason I'm shooting for Audiocontrol is that the country supplier here in Asia can provide us with one, complete with warranty which is very important to me. Plus since I'm an Audiocontrol city dealer, I can get them at good price from the country distributor. 



I'm just weighing between the Dayton EMM6 and the Audiocontrol CM125.

The Dayton is proven here in the forums but I still have to pay for international shipping plus customs tax which can really get ridiculous sometimes. Warranty is also important to me especially I've experienced DOA shipments before.

The Audiocontrol CM125 hasn't been mentioned (or i might have missed it) but it has a USB key with a FRD calibration file. This I can get through our country distributor complete with warranty and at a good price. Plus they'll be the ones to arrange with Audiocontrol should the product be DOA.

Any thoughts? 


For the meantime though, I'm getting myself familiar with the REW user interface using my current dBX/FiiO set up.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

I think a FRD file can be converted to a .txt file that REW can use; if you decide to go with the AudioContol mic you could open a new thread and probably get your answer.

It sounds like you’d be able to get the CM125 cheaper than ordering something from Cross Spectrum here in the States, but keep in mind that the AudioControl mic’s calibration file, according to their website, is only 1/3-octave resolution, so it won’t be as accurate as one of the mics from Cross Spectum. 

However – once again, this is only an issue if you intend do to manual equalizing based on an REW frequency response graph. If your only interest is measurements for acoustics data, as you noted in your first post, then the CM125 will work fine for that.

Regards, 
Wayne


----------



## JohnM (Apr 11, 2006)

REW can read FRD files.


----------

