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Review and Measurements of Lyngdorf RoomPerfect EQ

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amirm

amirm

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A comparison of the impulse response / energy time curve could be interesting to see as well.
I don't believe in ETC/impulse response measurements (they are quite misleading) so not going to encourage that by showing those results here.
 

stunta

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Thank you for the really well-written review. It is very easy to understand and is educational as well.

The first measurement shows about +15db of correction. As you mentioned, correcting up can overload amps/speakers. Does this unit take into account its own limitations? If yes, how can it take into account what load its driving? In other words, would 15db be too much and cause issues?
 

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I used an early version of Dirac a few years ago and had some problems with it. Not with its mic or measurements, but something about the kind of speakers I use. I have Linkwitz Orions, which are designed to interact with the room and light it up evenly. Something weird and phase-y happened when I ran Dirac to EQ the speakers. Now, possibly I'm just not accustomed to a smoother response -- I doubt I've ever had a room with decent acoustics since I started out in hi-fi in 1978. But another issue is that in my right ear, I have a hearing loss of several db at about 1-3khz, requiring some balance adjustment to get a stable center image. I couldn't seem to make that work out using the Dirac correction.

Anyhoo, I note that Amir has a big cancellation at about 65hz and peak at 110hz; I have the same basic thing in my room, though not quite as large, with some cancellation at about 50hz and a big peak at 79hz. What I've done instead is EQ through a software plug-in with my Mac Mini server running through Audio Hijack, or else using the new Roon parametric EQ. I just knock down the 79hz peak with a fairly high-Q filter at exactly 79hz. That removes the objectionable boominess. Everything else works pretty well with the dipoles bouncing stuff all over and the speakers well away from walls and fairly close to the listening position. That, by the way, is the Linkwitz MO. Maybe room correction and dipoles like the Linkwitz designs are not sympatico.
 
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Thank you for the really well-written review. It is very easy to understand and is educational as well.

The first measurement shows about +15db of correction. As you mentioned, correcting up can overload amps/speakers. Does this unit take into account its own limitations? If yes, how can it take into account what load its driving? In other words, would 15db be too much and cause issues?
Unknown. Its amplifiers are cool running/very efficient and pretty powerful so that is good. What load it is putting on the speaker, I don't know. This is why systems like ARCOS from Harman can be told the speaker model number and it uses that to know what is OK and not OK to do.

When I hand optimize things, I listen for the correction only in the trough and weigh the improvement. If it is tiny then I don't bother.

Note that there is no issue for bringing down the peaks. It is the dips that are potentially problematic.
 
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I used an early version of Dirac a few years ago and had some problems with it. Not with its mic or measurements, but something about the kind of speakers I use. I have Linkwitz Orions, which are designed to interact with the room and light it up evenly. Something weird and phase-y happened when I ran Dirac to EQ the speakers.
I turn off correction above 200 Hz in Dirac. That may have also worked in your situation. It is expensive software though so if the manual correction works, then no need to spend the money. :)
 

suttondesign

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Yup, and I may build the Linkwitz LXMini and just hand off everything below 90hz or so to a couple of big subs in corners, hopefully avoiding any EQ if I cross over steeply enough. Still thinking about it, since I've got a lot invested in the Orions, which have performed like champs for nearly 12 years.
 

astr0b0y

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I was under the impression that the 0 degrees position you have your mic in was for near field measurement of drivers and that for MLP measurement that includes room response a 90 degree positioning (along with a 90 degree cal file) should be used. Or does it not matter?
 
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I was under the impression that the 0 degrees position you have your mic in was for near field measurement of drivers and that for MLP measurement that includes room response a 90 degree positioning (along with a 90 degree cal file) should be used. Or does it not matter?
I usually point mine up or mostly up. However, in the video Lyngdorf has on their system they showed the mic pointing forward for the Focus point so I followed the same both there, and for my remeasurement:


There are differences in angle (and I think some calibration shops provide both angles). For my point of view, it is not that significant. Final judge is the ear in acoustics.
 

Blumlein 88

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This looks much like the later Tact results. I know Amir had/has one of the earlier units. The later units did the two chirps one for low/mids and one for upper/mid highs. The kind of correction looks similar. It wouldn't try to eliminate dips. I'm thinking they've made improvements, but it might be of a similar nature. The last Tact version in the XDM would prevent itself from overloading (earlier Room Correction pres would also if paired with the Tact amps) so I bet the Lyngdorf does as well.

Oh, for those who may not know, TACT and Lyngdorf were the same outfit at one time. Lyngdorf went his own way from Radomir Bozovic who was the guy behind the technical design of Tact. Even after the split there were many technical similarities between the two brands. I wonder if Boz is designing these for Lyngdorf again?

One of the odd experiments I tried with the later Tact was using two different speakers. A Soundlab ESL on one channel, and a Hales Signature Two sealed box speaker on the other. The system could correct enough in the sweet spot it sounded fine. Balanced, good imaging. Overall not quite the signature of either speaker, but if this were behind a curtain you'd never expect two different speakers in use. That impressed me mightily as for the benefits of room correction.

I've used Dirac quite a bit, and it does a good job. It does better over a wider listening area. From before and after measurements done by mitchco it looks like some other systems may do correction that is closer to the target curve.
 

Blumlein 88

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One comment about your listening room Amir. Do you use that same shag rug in the camper van? I could ask Thomas I suppose. :)

That is a nifty reel machine there. And you dressed things up nicely with red and white reels while displaying a split screen of mostly red and white on the flat screen. Okay two comments then.
 
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One comment about your listening room Amir. Do you use that same shag rug in the camper van? I could ask Thomas I suppose. :)
The carpet is called "modern shag." :) I especially picked it to be thick to eliminate floor bounce and to reduce RT60. It worked wonderfully for that. It is also great to sit on it to assemble computers and such. But boy, you better not lose a screw in there. It will never be found as they to go screw heaven! :D
 

Blumlein 88

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This is how you use "modern shag" for that pesky roof bounce. :)

1550384503093.png
 

Frank Dernie

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My room and speakers were set up by a friend of mine using MLSSA about 15 years ago. He is a specialist in room correction but I didn't have any electronics to do it so the speakers were positioned to minimise the magnitude of the excitation in the first place.
I did consider getting a Tact amp at one time and have had a demo of the Lyngdorf home theatre system and heard the superb Steinway-Lyngdorf Model D system at a dealer not far from here. I thought the Model D was absolutely amazing but the theatre system back then didn't seem so special to me, considering its price. They have changed a lot since then adding a lot of new stuff, only the model D seems unchanged.
https://steinwaylyngdorf.com
I do have a DSPeaker anti-mode 2.0 but because I use an integrated amp with mainly CD but also LP and a bit of streaming from a computer on USB and via ethernet I have no way to connect it so it works with all inputs so it is "resting" at the moment, though the improvement it wrought was not "must have" in my room.
 
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Krunok

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I fired up Room Eq Wizard (see my tutorial on REW here: https://www.audiosciencereview.com/...om-measurement-tutorial-for-dummies-part-1.4/). For microphone, I used my USB UMM-6 from minidsp with its calibration file (although I don't necessarily trust the SPL values shown). I placed the mic more or less where the focus measurement point was for RoomPerfect. I then connected to Lyngdorf TDAI-3400 using a USB cable and use it as a "DAC" to drive the speakers with and without RoomPerfect enabled. Here is a comparison of the system without equalization and with RoomPerfect set to "Focus:"

View attachment 22073

Very interesting review! :)

Can you please clarify in more detail how you got this graph? Did you make a sine sweep from a single position with both speakers playing and then applied 1/12 smoothing?

How many measurements did Roomperfect require and how large was the area you covered when moving mic between measurements?
 
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soundwave76

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Thanks and nice to see your gear and room. I agree 100% to what you say about room correction benefits. Have you ever considered to simplify your system with active speakers that have a built in DSP room correction?
 

Krunok

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That's very much true as wavelength of sound approaches the distance between our ears. In bass frequencies, the wavelength is much, much larger so singe mic measurements are reflective of what we hear.

If you move mic to a new position 20cm away and redo a sine sweep you would get different curve, so what exactly are you hearing as your ears are also 20cm appart? :D
 

Juhazi

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Some remarks,
- typically below 200Hz we measure modal response, so moving the mic a little doesn't induce great changes, but still we get very much different measurements from L vs. R speaker.
- when we measure L+R, we see summed response down low, then comb filtering wiggles. How high summing extends depends on speaker separation,+mic distance, and most of oll room dimensions.
- we hear (psychoacoustics) low frequencies by steady state response more than by direct response and first reflections.
- it is impossble to change reflections, room decay and modes with eq or FIR. Speaker and mic placement have a small effect.

I think that Lyngdorf has a made a wise decision to use different parameters for corrections above 200Hz.
Below is my measurements of L and R separately from different mic locations, and the average. I have eq'd that 50Hz bump, but it sounds too thin then (minidsp 4x10HD and 4-way diy speakers).
 

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Krunok

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Here's how it looks with my room and speakers, all graphs are with 1/12 smoothing.

Both (red), left (green) and right (blue) RTA response:



Left and right RTA response:



Left RTA vs sine sweep:



Right RTA vs sine sweep:

 
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