fitero
Member
Again, thanks for the multiple suggestions. I have had REW loaded in my server computer for a year or so but didn't have the initiative to learn DRC until recently.
You might like to download the trial version of AcourateDRC and play with it over it's trial period.Thank you for the suggestions.
As always, there are so many ways to skin a cat. I'm usually stuck for some time, like a deer in the headlights, agonizing until I make a decision.
I think I will buy Mitch Barnetts' book , a calibrated mic and play with REW a bit before spending money unnecessarily.
The Harman DSP not only acts as the crossover and driver correction, it also can optimize for the room including up to four subs run independently. It also of course supports many more channels and makes sure all of them are optimized for subs. I don't know of any other solution that can do this automatically. Alas, the room optimization is dealer only so not a DIY friendly solution.
Thanks! I haunt that site often, thinking about buying their preamp. I never noticed the trial version of the software. Ha!You might like to download the trial version of AcourateDRC and play with it over it's trial period.
I did and it gave me a bit clearer picture of things when I was trying to grasp a better understanding.
http://www.audiovero.de/en/acouratedrc.php
Driving that many speakers is not the key thing. What Harman ARCOS does is to drive each subwoofer differently as to optimize their sum with all the other speakers. They have patented this so I am pretty sure Genelec doesn't have it. See my article on it here: https://audiosciencereview.com/forum/index.php?threads/computer-optimization-of-room-acoustics.12/@amirm , you wrote:
«I don't know of any other solution that can do this automatically».
Genelec’s SAM system can do full DSP for up to 30 speakers. I guess that could be two for stereo and a bass system of 28 subs...:
I plan to start a new JBL M2 thread very soon. I got a little side tracked with a new subwoofer array. I will post my new measurements next week. @mitchco says he has listening position MDAT files from an M2 owner. Hopefully we can overlay the frequency and step plots to see how Audiolense does compared to the Harman crossovers and EQ. My money is on Audiolense.
I heartily recommend either using Acourate or Audiolense with the M2 and dumping the Harman DSP. You can’t use DIRAC because it does not do crossovers. IMO, Audiolense makes the most sense because you get great results (equal or better than Acourate) and it’s much easier to use and install the filters.
Again, Michael's Audiolense tuned M2 plus integrated sub tracks the ideal phase response virtually perfect.
Thanks Mitch! My step should improve a little more when I integrate the 2 high frequency stereo subs in my new 4 stereo sub array. It will eliminate pretty much all Allison effect reflections below 200hz.Here are a couple of overlays of the factory M2 versus Michael's M2 using Audiolense.
View attachment 10585
I have included the "ideal" speaker fr in blue as a reference. In this example, flat from 20 Hz to 20 kHz with a 4th order Butterworth roll off at 20Hz to simulate a vented enclosure. Given speakers are minimum phase devices, so is the filter. Michael's response includes subwoofer integration. As a side note, it is really too bad in the AVSForum shootout that in-room frequency response measurements were not taken. At the very least the relative differences between the M2 and Salon2 would have been revealed and likely account for the subjective tonal differences being heard.
View attachment 10586
Step response first 20ms - the factory M2 is not time aligned. The tweeter spike arrives first, followed by the woofer. Note how closely Michael's Audiolense tuned M2's track to the ideal loudspeakers step response.
View attachment 10587
Zoomed in view of step over 5ms. Here one can see clearly the factory M2 does not come close to the ideal step, which Michael's M2 is almost a perfect match.
View attachment 10588
Again, Michael's Audiolense tuned M2 plus integrated sub tracks the ideal phase response virtually perfect.
Same speakers, different rooms. But the room would not change the initial peaks in the step. Room reflections come back to the microphone much later.These are the same speaker in the same room, one using JBLs EQ and the other audio lense?
Keith
I am waiting on a couple more subs this week. I’ll finish setting all four subs up. I also moved one of my speakers. So I’ll post a new thread with new measurements. I’ll also overlay the JBL 4367 with the M2. I’ll show the basic steps of how I used Audiolense to generate the filters and install them in Roon.Wow! And where do I read the subjective swooning over how great it sounds now?
I need to learn how to do this with mine!
How big is your room?I can't fit a pair of M2's in my listening room so I'm gonna go for the LSR 708P's. I've been going around in circles, looking at the Revel bookshelfs, etc but this thread has helped me finally make up my mind.
To be perfectly honest, I quite enjoy my LSR308's and while I haven't heard the 708P's I'm taking a gamble that they will be a significant improvement and work better at higher volumes.
How big is your room?
I can tell you that M2's will work in that room without a doubt.It's a relatively large 19 by 16 ft "upstairs lounge" that opens to bedrooms, etc and has loads of irregular nooks and a staircase.
I'll do a Visio drawing this evening and post in a new thread.
The 308's would probably work well in a smaller room - hoping that the 708's better drivers and DSP/ amplifiers and drivers result in a step up.