Hi Torbjorn,
Very many thanks for your full reply explaining your situation and history (with Linn).
FYI I am aware that Linn SO has a generic ‘model’ for loudspeakers (type ‘Other’) and it is encouraging that you have access to an experienced Linn dealer and installer. Nevertheless if I might gently suggest that the Guru 28 will be compromised by modelling using type ‘Other’ as the detail available is less accurate positionally (limit of 1 cm) versus the Linn SO loudspeaker database entries which have the acoustic centres of (bass) drivers recorded to 1 mm.
Furthermore, the Space Optimisation database of loudspeakers has information that accounts for Ports and things like that. I note that the Guru 28 has two bass radiators on the rear. Did your experienced Linn dealer enter some special adjustments for these rear facing elements in your SO Room Design?
If not, I strongly recommend that your Linn dealer provides the necessary information regarding the Guru 28 to Linn Products Ltd. The dealers should have had the necessary training to capture the information from an example loudspeaker.
Failing that - if you wish to try to continue using Brand and Type ‘Other’ - I can give you some suggestions in the meantime.
I do not wish to persuade you away from your path with the WiiM and PEQ - but for information I produced three technical reports for Linn in 2024 because I had discovered problems with the reliability of Space Optimisation when used in my room which also happened to have some GIK Acoustic panels already fitted.
The outcome of this work was that Linn Products Ltd amended and clarified their guidance in the Room Design part of the Space Optimisation software.
At the same time, I developed a tuning method that uses REW with a calibrated microphone that allows users to correct for any drift in the filter estimates that Linn SO is generating.
This tuning method is available in the public domain on the Naim Forum by clicking this link here.
IMO @Simon-in-Suffolk and others have given excellent advice here (particularly the advice not to EQ the 600Hz to 3kHz region).
I agree that you should not need to go to DIRAC Live. My additional tip is that if you wish to continue with the PEQ method, do take a look at the phase curve under the SPL and Phase tab of REW in the region from 20Hz up to circa 100Hz.
The objective is to try to get the phase curve for both L and R as linear as possible - which is what Linn Space Optimisation does if set up correctly with correct data for specific loudspeakers and accurate Room Design(s).
Regards,
E of E