Hello. Does anyone have experience setting up a UMik-1 USB mic with the REW software with a DCS dac like the Bartok? I’ve just bought one and I’m afraid to do some mistakes. Many thanks. F.
There shouldn’t be any obvious problem for making acoustic measurements. You won’t be able to use USB2 as that is configured for flash drives. AFAIK the UMik-1 runs as 24/48 so I would see no obvious difficulty running the signal source software installed on the computer into USB 1 which I am presuming is what you initially want to do. Just keep the volume control down on the amplifier until you are sure that it is working OK and that you do not blow your tweeters inadvertently.
Do you mean that you have just bought a UMik-1 or just bought a Bartok?
Incidentally, what do you want to do with the measurements ultimately? I am imagining that you have a purpose.
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Franco, not a problem per se, but there are a couple of settings to be aware of that could impact REW’s results;
- Turn off the Bartok’s Buffer - It doesn’t affect the frequency response directly, but the buffer delay will affect REW’s chirp gating for the FFT
- Set Filter to F1 (PCM) - REW expects a standard brick-wall filter, any other filter setting will likely give you a somewhat skewed results due to their varying transient response, and phase/group-delay measurements
- Set upsampling to DXD - Not a big issue, but REW’s response results will likely deviate if the analog conversion is via DSD
Happy measuring!! 
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Thank you. My purpose is to correct my room acoustics. But I’m a real newbie in this field.
Good luck. There are basically two ways to look at this area :
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To actually correct the room’s acoustics by material means ( adding diffusers, absorbers etc). This can require proprietary solutions of which there are a number available to home audio enthusiasts. However much can be also done simply with normal room furnishings e.g. the placing of a filled or part filled bookcase or using curtains( drapes) and carpets or rugs.
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Alter the frequency response of the speakers ( usually electronically) to inversely mimic the room’s acoustic characteristics.
The first course is IMO the only truly successful route as it deals both with problems in the time and frequency domains and provides a correction at most points in the room.
The second course will only provide a correct frequency response at the point of measurement ( and thereby) correction. There is also a question of compatible audio quality when dealing with very high end reproducing equipment such as Bartok.
So If it were me I would pursue the first route in preference. In fact I do to a small extent by using diffusers at my room’s far end ( the speaker end).
If you do go the electronic way then try to use a component of broadly similar qualities to Bartok. In particular I would not advise using any solution that means that you have to use the USB input to Bartok as this is inferior to the network input and what you gain by having a quasi flat response at the listening position will be offset by the overall quality in comparison to use of the network connection.
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Not technically true these days actually 
.
Tools like Dirac Live can correct in both the frequency and time domains (digitally) when coupled with a compatible standalone DSP platform, like those from MiniDSP. It can work quite well for anyone who has no choice but to room correct actively.
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@Anupc is right. If you like to read a very comprehensive article on Dirac 2 (link after the quotes):
Can we make an already great sounding speaker sound better in my room? And by better I mean smoothing out the low frequency response below the room’s transition (Schroeder) frequency, making small, broad band tonal adjustments in the midrange and top end to be a bit smoother and finally a timing correction of the impulse response.
The short answer is yes we can. We can see the improvement in the measured frequency and timing response. I can also hear an audible difference with a tighter, more clear sounding bass, smoother overall frequency response and a more coherent timing response (i.e. stereo imaging and depth of field) across a larger sweet spot.
With Dirac 2, designing and generating a partial correction from about 600 Hz on down below the room’s transition frequency is as simple as it gets. The sonic benefits are instant, much smoother bass response with no huge peaks and dips that plague virtually every room below Schroeder frequency. Full range correction comes with improved phase response (i.e. imaging and depth of field) covering a wider sweet spot, more on that in the subjective listening section.
[…] Well folks, it is 2020 and if you are not using digital room correction, at least partial correction to smooth the bass frequencies in your listening room, you are missing out on a simple but audible optimization.
From:
Thanks Pete. I’m trying to go for the first solution (ie, room correction) but I want to do things right. Hence the idea of the UMIK. I’d love to hear somebody’s experiences doing this exercise through the Bartok.
The UMIK-1 is a low cost measuring microphone compatible with the free REW software. The combination is normally used as an analysis tool.
For the room correction itself, you need either create a filter from your REW measurement and use this with a streaming software and a plugin on your PC (Bartok only used as Upsampler/DAC; I did not yet try this method out) or an external room correction hardware (e.g. miniDSP Dirac Live Units).
In the latter case the problem with dCS gear (i.e. Bartok, Rossini, Vivaldi Upsampler) is, that you cannot insert an external room correction unit between the streaming function and the upsampling function/DAC. Using dCS gear for streaming would require a separate Network Bridge.
Basically I would not recommend using a room correction with analog I/O (i.e. between DAC and amp) because of the necessary additional AD/DA conversion, where the DAC involved can almost certainly not match the Bartok’s.
Room correction hardware plus software available are miniDSP Dirac Live Series (e.g. DDRC-22D with Dirac Live 3 software and UMIK-1 for approx. USD 700), Trinnov ST-2 Pro or HiFi with optional 4-element microphone (ST-2 Pro for approx. USD 4400 plus approx. USD 750 for the mic, ST-2 HiFi costing somewhat more) and Accuphase DG-68 (for approx. USD 25’000 in the US, EUR 14’690 in Europe).
IMHO a miniDSP DDRC-22D with UMIK-1 package would be a reasonable and affordable starting point. The actual room correction uses Dirac software, but you can still verify what you have done with REW.
Using UMIK-1 with REW and Bartok:
Go to minidsp.com and download the calibration files for the serial number of your UMIK-1.
There are two of them: one for pointing the UMIK-1 towards the speakers and the other one for pointing the UMIK-1 towards the ceiling.
Install the dCS USB driver for your Bartok. Select this driver as standard audio output in Win10-Settings-System-Sound.
Connect a USB cable from your PC to the Bartok and select USB as input.
Connect the UMIK-1 to a second USB on your PC.
In the REW select standard audio output and the UMIK-1 as input. Load the calibration file.
You should now be able to get an REW signal output on your speakers (start with low volume!).
After adjusting the levels you can do your first measurment.
There is more information and tutorials about REW on
AV NIRVANA.
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