Measuring room with RTA

Rooms and Treatments
1

I have gotten interested in finding out what’s going on acoustically in my room. I’ve been doing research and have learned quite a bit, but I’m still not sure about some things.

I have an app on my iPad called AudioTools which includes an RTA. The screenshot below was taken using this tool, playing pink noise with a C weighting, averaged over a couple of minutes. I believe that this is the right method, but please let me know if it’s not.

Test iPad 2025 internal
Test iPad 2025 internal2360×1542 172 KB

I don’t have an external mic that works with my new iPad (2025), so I use the internal one. When I start the RTA, I get a message “Calibration for device iPad 15,8 not found.” Is this a concern? The AudioTools manual gives directions for calibrating a mic, but it requires equipment I don’t have. I’m not trying to get anything super precise at this point; is the internal mic “good enough”?.

I don’t think these results are too bad for an untreated room — or am I being overly optimistic? The speakers are Magnepan LRS+ which are expected to go down only to 50 Hz; so it’s not surprising that there is a drop off at this point. I own a Victorian house (bay windows, pocket doors opening to adjacent rooms, etc.); the listening area is highly asymmetrical. Not being in a rectangular box is good because I don’t get standing waves or have a problem with early reflections off sidewalls. But I don’t have much leeway in terms of speaker positioning.

I’m considering a subwoofer that allows one to equalize the speaker output centered around five bands. If I use this to lower a couple of the peaks and raise a couple of the lower readings, would I be getting something reasonable? Given my complicated and asymmetrical room, I’m not expecting perfection, just something better than what I’m getting now.

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Yes, a subwoofer would be nice with the LRS+.
Just make sure you get a sub with a speakon connection that receives signal from an amp versus an rca or XLR from a preamp. REL is the recommended brand because they have that connection and claim that there is virtually no load on the amp with the speakon connection. The S/510 or S/812 subwoofers are what I would recommend.
Others in the past recommended REL but didn’t mention why, I have experienced a sound quality dropoff on the rest of the system when using multiple preamp outputs.

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Thank you; I will look at the REL S/510 or S/812. I have a BHK preamp and will only use one set of outputs (the XLR). I have read on this forum that RELs have an issue with humming when connected to a BHK250 in standby mode. There is a way around this, it seems, by purchasing a kit from REL. But I’d prefer not to make things any more complex than they have to be.

I’ve been looking at this sub designed for use with small Magnepans (I would need a pair, which seems to be a good thing anyway when dealing with subs).

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