Finally decided to have a go at some room measurements (wish me luck)!
Stage 1 completed - successfully downloaded REW software.
About to order DSP UMIK microphone.
To connect laptop to my 272 can I use USB from laptop to front USB input on 272 or will I need to go from headphone out to RCA inputs?
Many thanks
Stu.
If the 272 USB input is similar to that on the Nova, it will not accept a USB signal acting as an audio âline outâ from a computer, as it is only meant to be used to connect an external USB storage device like a thumb drive or external HD. Also, I seem to recall (although I admit it has been a while since I looked) seeing something in the REW instructions that you should use the headphone out on your computer.
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Many thanks Maison
The 272 USB input is a bit different to the one on the Nova, but neither if them will do what you want. You can play from an iOS device into the 272, but not from a laptop.
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I unwittingly swopped to the âListening Room Realityâ thread which now seems to have disappeared. A few people had asked me to post my findings so will continue on this thread.
I am still learning so bear with me.
I have know idea this compares to most rooms with minimal treatment. I can obviously see there are some differences between right and left speakers due to room asymmetry.
I have a big peak and long reverb time at 30hz. I wonder how relevant this is as most of the music I listen to wonât go below 40hz on bass guitar. I will take some further measurements over the next week or two and try and make more sense of them.
I really donât think my room sounds too bad, I just wonder if it is possible to get a slightly more even bass response.
One subjective thing I perceive is that bass seems to perform better when the room is warmer. I will try and take some objective measurements to see if this is correct?
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Looks like I have posted 3 images of the same SPL graph. Blue line being both speakers.
Stu,
Whilst I donât know how your measurements were taken and can see results have 1/6 smoothing applied they look pretty good 
.
Iâd be surprised if you donât hear 31hz peak in some tracks but if it isnât an issue no point in trying to solve it, unfortunately mine was too noticeable.
I couldnât resolve mine without applying some DSP which goes against grain for Naim - signal purity and all that - but was worth it for me. The filter I used was a like a virtual bass array (mirrors the effect of twin sub woofers) with two stereo speakers designed by a chap called Obsessive Compulsive Audiophile who has a YouTube channel to provide instruction and best of all itâs free 
.
Good luck however you decide to go.
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Not sure what happened, but the Listening Room Reality thread is there now, so only a tempoeary glitch
I havenât been following this here or in the other room, but the things that strike me most apart from the huge (approx 15dB) peak centred around 30Hz are another hump around 130Hz, though only about half the size, and dip of about 5dB around 260Hz. But the 1/6th octave smoothing will probably be making them all look smaller and broader than they are. The waterfall shows the long decay time of the 30Hz, likely to give a very boomy sound to anything down there.
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Following because I just bought the same microphone to get some in-room measurements for my new subs (REL S/510 stereo pair. I have the software installed, and plan to use the headphone output from my M1 MacBook pro into my NDX2 for this.
Thatâs as far as Iâve gotten.
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I agree with StuW. Unless your into bass heavy music it looks pretty good. Can you get an impulse plot so we can see how the timing looks. However i suspect it will be fine. When i did it i couldnât work out why the speakers were 180 degrees out of phase, until i noticed one had the wires reversed, silly me!
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Thanks for the feedback I really appreciate it as this is all pretty new to me. I will look at the impulse plot and post later today.
I played some bass test tones last night and listened at different points in the room. In my listening position 40hz seemed to be the most prominent frequency. I didnât check 30hz but will do this today. I was under the impression that my ATC SCM40 donât output much around 30hz but they clearly do from rew results.
What was really interesting is that at ear height in the sitting position most frequencies sounded pretty uniform. Moving around the room keeping my ears at sitting height did produce dips and peaks but at standing height there were some very high peaks from 40 to 100 Hz. The most problematic areas being the corners as we know but also the wall corresponding with the left speaker which is a bare wall. I have used some absorption here for first reflection point but never above 1200mm height. I will try raising absorption here and see what happens.
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Here are the SPL and Phase and the impulse graphs.
I must admit I am completely phased by the phase plot (physics was never my strong point) but will read more to try and understand it.
Wasnât sure what smoothing to use as there seems to be a variety of options recommend from what I have read.
I also have ordered a mic and intend on doing some measurements when it arrives. So will be watching this thread with interest
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I have been planning to do this for quite some time but figured it would be too difficult as my IT skills are pretty poor. I actually found it pretty easy to set up and take measurements as there are plenty of instructional videos and literature to follow.
I am starting to understand the results, however improving the room is going to be the challenge. The encouraging part is that my room doesnât seem too bad.
I ran some more bass tones again today and from my listening position 30 and 60hz are probably the most prominent frequencies. Listening to music there still seems to be some boost around 40hz area.
I have adjusted the spikes on the speakers as they werenât levelled correctly and this seems to have given a more even response in the other bass frequencies. Will do some more testing this week.
You are unlikely ever to get an even response throughout the room unless you create an anechoic chamber⌠The only area you need to worry about is where you listen. (But treating on key places reduces the reflections that cause peaks and troughs.)
Meanwhile Iâm curious - you say youâre waiting for a microphone, so how are you measuring at the moment?
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Thanks IB, yes the listening area is key and I wondered if trying to find areas of increased bass resonances would be areas to focus treatment.
I have my UMIK and looks like haydj is waiting for his mic
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Im expecting a parcel today
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I have my mic, but stumped at the moment trying to connect my MacBook to the ndx2. At this rate I may have to re-commission my dac-v1 and connect it into my nc52 as I know that does work.
Using bluetooth and airplay didnât seem to work very well
Are you connecting from headphone out to RCA input on your preamp?
Iâm not yet sure how I am going to connect my M1 MacBook Pro (or the M2 MacBook Air I am getting soon) to my system for using the software. The older Intel-based MacBooks had headphone out that doubled as optical out and I could have used a 3.5mm optical to Toslink cable (which I still have) as in input to the NDX2. Sadly, the newer Macs no longer have that.
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