Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems MRC - Too many filters?

When you over damp mid-HF, it sometimes has the subjective effect of making bass sound even more prominent, as you've damped everything but the bass. Then, when you correct the bass, everything is effectively 'over damped' and could well sound thin and lifeless. If you have over absorbed mids-highs, no amount of speaker positioning or MRC adjustments will help, you'd have to remove some of the absorption. Not saying that is the case, you obviously need to play, but maybe worth bearing in mind? I take it you were fairly happy with your system before you put all the new acoustic treatments in place?

The stuff on the ceiling is:
75% Aurica Wedge Acoustic Foam
25% T'Fusor Sound Diffusors

The stuff on the walls is Bonded Acoustical Cotton

The walls are covered for about 60% of their area (from 2' to 8' above floor) with the panel above, the rest is just hardwall. Below 2' are the bookshelves that basically act as diffusors breaking up the reflections.

I have the old MSL and the new MSL and I am sending them out to some FMs who have asked for them.

As to the sound, I don't really feel that the mid/high is sucked out but let me do a critical listen again and revert with exact impressions.

I also plan to move the speakers closer to the wall (their earlier position) and do the MRC and listen. Will post tomorrow.

Thanks a lot and very happy to respond to all the PMs.

Regards,

Not that I think it's the cause of your current problem, but bookcases as diffusers is a myth.
E.g. Absorption and diffusion of bookshelves

I spent the last couple of hours doing the following

1. Moved the speakers back towards the wall. Now the gap is only 9" instead of 3 feet.
2. Moved listening spot forward correspondingly.
3. MRC again.
4. Filters at 400, 450ms
5. Finally chose 450ms with +1.5dB treble.

Things starting to sound familiar now. Let's see how it pans out over several sessions.

Thanks a lot for all the assistance.

Question- Is there a "right" decay time for a given room size?

Good to hear you are making some progress and getting better results
I like a 350ms RT60 cut off for the tightest bass , non MRC but it depends , some folk like more. It's a suck it and see type proposition.

Try fine tuning your seated position , a lot more effective than moving speakers , easier too , what with 8000's

I recently had a play with the room simulator in REW (Room EQ Wizard), I'm not saying it's totally accurate, but it might help narrow down rough positions for speakers/listening position which you could then fine tune.

NO, we all have rooms to listen what the industry have produced for us. And the industry have standard rooms with specified decay/reverbation times.

To hear records correctly, your reverbation times at your "listening" room have to be shorter to hear what the combination of record and sound engineer have stored on the CD or whatever storage medium.

So for listening room you should be in the range of 250 to 350 ms (milliseconds).

Not scientific, but based on experience, to me the pictures look like you have a combination of heavy absorption in the high frequencies (the ceiling), and reflectivity in the walls. I'd work on increasing the diffusion significantly.

I'd add some bass trapping first, most small-medium rooms need proportionately more bass trapping.