When you open the saved file, there’s a lot more info than there is shown in the picture in the reply above.
Here we have exactly what you do see.
That should work too unless there is a gap in the loop. You can create longer files by amending the sequence length, too long is better than too short.
The graph looks a lot better than your previous one, the lumpy bass is probably wall related, mine is similar. The SPL seems a bit low though - you don’t need to move the mic around when setting the 75dB level.
I used kitchen chopping boards to move my speakers about easily to reduce any bass boom. Some toe-in changes also reduced the bass boost by 1.5dB. The rest I deal with using DSP in Roon, with separate Parametric for each channel.
In case it helps, the mic is omnidirectional so does not need to point towards the speakers, making it easier to hold and move whilst measuring if you are doing that way, But hold at the far end of the body trying to keep your hand/arm well away from the tip, and not between tip and reflective surfaces etc - e.g. if measuring close to your ear hold with the hand against the front of your shoulder and rest of arm tucked against your body. Ideally you should be holding the tip very close to your ear and moving your head and mic simultaneously.
You can also take static measurements with the mic held by a stand or clamp, positioned beside your head, taking readings in mulitiple positions, to see the variability.
1 Like
I feel like I’m getting somewhere with this now!
The playback of the PN file seems to be seamless but I’ll do new files with extended play time.
The thing that really stands out to me is the trough starting at 100 hz.
Are the bass peaks at 45hz and 70hz cancelling the 100 to 125 hz range?
The Umik comes with a separate calibration file for using a 90 degree if you wish to use it in that manner.
I’ve got a trough too at around 100Hz 
If you move your speakers around by a few inches or so you could end up with a more balanced response. Best practice seems not to attempt to fix deep troughs so I’ve only corrected for spikes.
Currently testing a convolution filter…
I’m standing behind the listening position, holding the mic in the provided tripod/holder at arms length, spiralling the mic slowly, back and forth in the space where the listener’s head would be.
Now I know that I’ve got a proper baseline reading, I’ll have a go at fixing those low frequency peaks.
I had planned on building floor to ceiling bass traps in corners anyway. Now that I have proper measurements confirming the need for them, I’ll get on with them happily, knowing that I’m not wasting my time and money.
I’m not aware that bass traps will go down that low? 
Just had a look on the Gik website.
Their Monster Bass Trap with Range Limiter seems particularly effective at 80hz, so that would be great for the second peak on my graph.
You’re right about the 45hz though. The same Monster bass trap barely touches the 45hz range.
1 Like
Just added some updates. Hope it’s all clear.
1 Like
Am I correct in thinking that the EQ bit that you’ve just added creates a file to be used with something like Roon?
I have nothing like that for two channel listening, apart from if I were to use HEOS on my AV Receiver.
Yes, this bit is if you were wanting to add a Convolution or Parametric filter on Roon. So not currently any use to you 
1 Like
What are the chances that my setup isn’t actually playing the frequencies shown in the trough?
(I did say that I’d have no shame in asking stupid questions)
However, deep troughs indicate missing music in the range affected. Fixing generally requires repositioning of speakers and/or listening position (in my case a fundamental rearrangement of room), and if the best that can achieve is insufficient then bass traps covering the relevant range, though latter can be bulky, and/or expensive. But the one thing never to try is boosting frequencies electronically to remove deep troughs instead of tackling the root cause (room/positioning) if they are due to cancellation, as that is a surefire and rapid route to speaker destruction (every 3dB boost doubles the amplifier power, a deep trough risking driving the amp to clipping, which is a common cause of speaker failure).
2 Likes
As with @Slug’s system I have deep but very narrow trough around the 110Hz point that I eliminate from the DSP calculations. For me I think it’s most likely the size of the room and the distance between the speakers, I’ve done a fair bit of moving speakers to smooth the bass response (always listening first and then confirming with REW), then adjusting toe-in to get some depth whilst ensuring that vocals still sound clear. Even the toe-in adjustments changed the bass response for the better.
Only then did I add a bit of DSP with Roon.
1 Like
Having digested what I’ve learned recently, I’m going to try and track down the cause of the null.
When I get a spare hour, I intend to make a recording of the problem frequency and play it on a loop, whilst wandering around the room with the UMIK-1 watching the SPL meter.
Once I find the loud spot, I then need to decide whether to reflect it back where I want it, or absorb it.
I could of course be talking nonsense too. Feel free to correct me.
1 Like
I found it quite illuminating playing test tones or slow sweeps, finding places in the room where some tones disappeared completely (but not necessarily the same places if speakers moved).
Well, this is entertaining. Not able to spend a lot of time on it for the near future, so I just streamed a couple of tracks (Suzanne Vega “Calypso” and Al Stewart “Year of the Cat”) via the Allo+nDAC though my 82 to the 250 driven active SBLs, and just let the RTA window run. And it looks like this:
(Dire Straits, “Ride Across the River”)
with a nice big hump around 50Hz.
I think I’m going to have fun with this toy - especially when I get to the Aktiv Briks!
More like a dip betwee 60 & 100 Hz… However of course what you don’t know is the content of the music - to do that you could feed the output from your source to the computer, and run the same, then compare.