After doing some reading on REW Room Acoustics Measurement and how it has helped many NAIM users on this forum to better understand the pitfall in the rooms and look into treating them, i am intrigued to give it a go. Would like to do it before going ahead with some acoustic room treatment gears such as bass traps, absorption panels and diffusers so that i have a reference point before and after room treatment. Also to be used to get better advice on what to use and where.
From what i could understand, you only need a mic such as the MiniDSP UMIK-1. Is that all?
On the miniDSP website, it mentions that you need a cable to connect from your laptop head phone to the pre-amp. How is this done? What type of cable is needed? And do you also require a DSP such as the miniDSP 2x4 HD as suggested in one of the online videos i watched?
I have never used a cable to connect my Windows PC laptop to my NAIM system since i have always used uPnP (NAIM CORE) or streaming services such as Tidal and Qobuz, and recently using ROON from my laptop.
You need to buy a calibrated microphone, prefereably with USB interface and connect to your PC running running REW. REW will be expecting the configuration file of the microphones measured performance so as to correctly interprete the info sent by the mic,
UMIK-1 is a popular affordable option.
You also need to stream quality pink noise into your audio equipmentā¦ create a file and play from usb is what I do.
You then need some patience and trial and errorā¦ to build profilesā¦ it is not an an exact process if you want it to sound natural, ā¦ (our sears donāt behave as a single microphone) ā¦ much on the web about this. Keep filter changes minimal so as to limit other distortion and smearing issues.
You can also connect the output of the computer running REW to an analogue amp input, and play pink noise, or frequency sweeps directly controlled by REW, which is a very simple and convenient process, albeit possibly limited at frequency extremes depending on the computerās sound card.
You can but I donāt find the DACs and output stages of PCs/laptops really very goodā¦ and this needs to be as accurate as you can get for it to work correctly, and best obviously to use the DAC that you will be using for playback, otherwise your calibration will be out.
The simplest way is cable with a 3.5mm stereo jack plug to twin phono (RAPCA) plugs, going to the preamp. In REW if you play a tone direct, you can then tweak the laptop and preamp volumes as necessary to give you a clean signal with lowest background noise (usually as high a level as the computer will give without distortion), but in reality it is likely to be useable over quite a range. The cable does not need to be anything fancy. In the computer you will need whatever output setting gives an unmodified output - i.e. any tone control selections disabled. The appropriate output might be called something like āspeakers largeā, though the headphone setting probably would also suffice,
Sure, but if you canāt do it properly I suggest itās not worth doing at all, especially if you are going to put the filter kernel in your replay chain, as not doing it right has risk of really mucking the quality of your audioā¦ and if using Naim them most will be sensitive to this.
But sure as an idle curiosity that is not going anywhere near your replay chain then any general pink noise would doā¦ and you wonāt need a calibrated microphone like the UMIK-1ā¦ you could use your laptop built in mic.
Yes, it depends what it is being used for. Everyone I have a
Encountered using it has been to check and assess in-room response to assist with speaker and listening position placement and/or room treatment requirements, or to set up a sub.
Certainly if the intent is to play music through it, using it for room equalisation, then it would need the same consideration as other components in the digital sound chain, and certainly not use the computerās DAC for music replay. I had overlooked this use because I havenāt come across anyone using that way. I donāt know what the OPās purpose is?
My primary need for REW is for fine tuning speaker placement and for deciding the best way to go with acoustic treatment. This is my living room and not a dedicated listening room, hence looks are crucial (well, more for my wife than I).
I would like to see the reverberation numbers on various frequencies and see where the problems are so that i can go around fixing them. I know that i can send REW data to companies like GIK or Vicoustic and they can tailor make a solution.
I also want to keep reverberation curves during each stage of acoustic treatment, even if simple things like changing a curtain to an acoustic grade curtain which is something i am currently looking at.
I live in Dubai and hence not easy to order or test any of those products.
Once I get the hang of REW, i can also then look at room EQ, but to do that, i probably need Audioquest Dragonfly or something similar on my laptop to produce a better signal to my pre-amp since this seems imperative for EQ.
That sounds like a plan! And yes, sort out the room as best you can before considering EQ - and you may find it is not necessary, depending how flexible you can be with speaker and listening position in particular. If you do go down that path be very wary of boosting frequencies to fill dips in response: remember that each 3dB means that when that frequency or range is playing the amp will be putting out double the power, and you can very quickly reach the point of driving the amp into clipping if playing loud, with associated risk of speaker damage. And if a dip is a room cancellation, no amount of power will bring it up as the cancelling reflection increases identically.
Thank you @Innocent_Bystander and @Simon-in-Suffolk for your advice, i have ordered the miniDSP and just received it today. Will be doing some reading on how to use it with REW, and hopefully should start using it and do a speaker placement measurements soon.
Connected UMIK1 through USB to my laptop, and downloaded from the internet Pinknoise, copies to USB and plugged into my NDX.
Very informative, shows i have a big drop between 50 and 60 Hz, i guess this is due to room geometry, will get this over to GIK and seek their advice on some room treatment to take care of this.
Will be doing some reading on this, there is a sea of information.
Hi, the drop or equally often peak (boom) around this range is as you say down to room geometry and reflectionsā¦
You may find moving the speakers or listening position radically changes this bass responseā¦ it wonāt necessarily sound bass light, which in my experience is around 100Hz to 400Hz, but you may feel itās light on the deep bass or what some people I think calle āslamā of the sound.
I would ignore anything below 30Hz is there is little or no info there, and most commercial music has this filtered off.
The area that appears critical is the 500 to 3000 part, where there is much information. The higher end of this can be prone to reflections causing a comb like response of constructive and destructive interference. This can be the difference between a system sounding natural or artificialā¦ room furnishings and speaker placement can affect to. Yours appears well behaved, I suspect your system might give you a slightly warm sound?
My room is a weird setup since it is a living room and not a dedicated listening room.
As you can see in this picture, the music system is in the left part of the room where there are sofas, the right side of the room is occupied with a pool table. This is an very setup since i have a left sidewall, but the right side wall is far away from the speaker and on the other side of the room. So i guess there must be an issue of timing since the reflections are not symmetrical.
My plan is to order movable sound absorption panels that can stand on the floor and hence somehow create a sort of right side wall to the speaks, this i guess will enhance the current warmth of the sound and allow it to open up. Bit of a hassle though since i have to move them back and forth when doing serious listening. If i do this, i can do i on both sides, left and right of the speakers.
Hello @Simon-in-Suffolk, i have a question regarding your recommendation to play sweep pink nose direct from USB on my NDX2 since my laptop is not wired to my Preamp. My question is, when i click measure in REW, i have only two options in Playback, either āFrom REWā or āFrom fileā. There is no option to disable playback option, what is the best way around this? Tried searching online but could not find any way around this. My laptop does not have audio out, only mic input.
Use REW to create the fileā¦ play from USBā¦
On the PC playback, just turn down the volume or mute, you wonāt be using itā¦ and at the same time hit play on the streamer for the USB
