The Listening Room Reality

Hi @Mark63 ,

To answer your question : no, don’t buy new speakers, at least not yet.

Your measurements aren’t so bad. It could be worst, trust me.

I wouldn’t worry too much about the low end as you won’t be able to really correct that. I would worry a lot more about the 250 Hz – 1 kHz range…

There are some rooms posted on System Pics 2020 that probably measure even worst, and their owners seem to be satisfied.

This tells us a lot about how our brain can manage and reconstruct all that mash (fill the gaps, attenuate, and so on…). Pretty amazing, isn’t it?

In a regular room, untreated, what reaches your ears is roughly 50%-60% reflections and only 40%-50% of the speakers’ direct sound.

Listening fatigue is a sign that you’re brain is working hard to reconstruct what you’re hearing :wink:

Treatment will change that ratio. The more treatment, the more you’ll listen to your speakers. It is that simple. And you might discover that your speakers aren’t so bad. But you may find their limitations as well.

As for your measurements, I suppose you have a calibrated microphone and use it correctly. Be aware that measuring isn’t an easy task. But there is a lot of information available.

What you want to look at when measuring is roughly the following :

A - peaks and nulls (the graph you posted)
B - decay time (waterfall graph)
C - RT60

This will be your baseline for treatment.

A and B are mandatory. You want A as flat as possible and B as even as possible.

C is a matter of taste.

  • First thing first, the listening position is the very first thing you need to sort out.

  • Then speakers positioning.

  • And finally treatment.

If you’re limited in speakers positioning and listening position , then you may somewhat compensate that with the appropriate treatment.

In your context that means covering the back and front walls with something like GIK Monster Bass Traps, and the ceiling with GIK 244. Or an equivalent setup.

If your not limited with positioning then place the speakers length wise.

Now treatment :

  • 2 or 3 panels won’t do much.

  • You’ll need a significant amount or treatment in order to achieve your goal : listen to you speakers.

  • Avoid foam and acoustic curtains, at least at first.

  • Go for 6 inches thick (or more) Rockwool, or Fiberglass, broadband traps (like GIK Monster Bass Traps).

  • Avoid diffusers! Diffusion is really nice, but you’ll need a lot of surface to get a result. Start with broadband traps (like GIK Monster Bass Traps).

  • Symmetry is key.

  • First reflections points is a good target to start with : left-right, front-back wall.

  • Don’t forget the ceiling! Remember, floor to ceiling is a really short distance… and the ceiling is a gigantic flat surface…

  • Don’t buy one or two panels “just to try”. It won’t change anything and could generate an imbalance.

  • Make a plan. Take your time, and think about it carefully.

  • Be aware that it’ll cost you money! My own treatment costed me ~12K euros. And I’ll probably add another 5K.

  • You’ll spend at least 1,5K to get a proper result. A cheaper alternative would be DIY.

  • Treatment will give you the best ratio performance/cost.

  • Read. Watch some videos. Don’t pay too much attention to forums…

  • Learning is key. There is some useful info on this thread. If you’re not willing to do some learning, then you’d better hire someone to help you.

Hope this helps :smiley:

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Hi @Thomas

That is really very helpful, thanks a lot.

I used a UMIK-1 calibrated mike but only took measurements at the listening position, not at several points around it as pointed about above. Apart from that I think I’m using it correctly, it’s very easy to setup with a Mac, but will read more about it before doing the next measurements. Whilst I’ve looked at the waterfall and RT60 graphs I don’t really know how to read them … yet, more reading required!

Yes it’s amazing how our ears deal with all this, the unfiltered graph is a huge mess, especially at the higher frequencies where it’s a mash of massive peaks and troughs.

Just out of interest here is an image of what Audyssey EQ did in this room for one of my front speakers, quite a difference!

Since I will naturally be limited in how much treatment I can do in our living room I’m wondering about a combination of treatment and EQ. The latter doesn’t seem to be discussed a lot here?

I’m doing a room plan on the GIK Acoustics site and will send it to them for advice along with more measurements.

I have started with listening position and speaker placement, spending most of yesterday on it. I have moved the sofa away from the wall about 15 cm which is about all I can do for the listening position. TV and projector screen (which comes down in front of the TV) dictating that more than anything.

I’ve had very nice improvements from the above and speaker positioning, adjusting width and toe-in etc. They are further from the wall and with quite a lot of toe-in now (can see the inner sides of the cabinets still). I know, Hi-Fi 101 there :slight_smile:

I initially tried the setup described in this topic https://community.naimaudio.com/t/creating-a-soundstage-speaker-placement-a-massive-improvement-for-zero-cost/1349 but to be honest didn’t really get anywhere with it.

I watched the videos you linked on speaker positioning along with one from Dynaudio (https://www.youtube.com/watch?v=8b1W7QgqhR8&t=1133s&ab_channel=Dynaudio) as guides, using the music recommended in the latter.

The results are great so far, I can really hear the instrument placement in the “Bird on a Wire” track and “Amused to Death” by Roger Waters is an amazing listen now, with the soundstage now going well out beyond the speakers … if I close my eyes I can no longer tell where the speakers are :slight_smile:

I’m going to listen with this setup for a while and get used to it before tweaking more … I can move my head to the right and vocals remain in the centre but if I move to the left they move to the left with me, which is weird! So still some work to do on that.

I was fully expecting to have to upgrade my speakers when I bought the amp & streamer but was pleasantly surprised by them, it’s as if I’ve already bought new speakers. So I’d like to see how good I can get things and find their limitations which should help with my choice of new ones when the time comes.

Thanks again, really appreciate your advice.

Cheers & Happy New Year everyone!

Mark

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enclosed the measurements for my room. I asked an expert over to do them for me and advise if/what treatment is necessary

We will start with a number of bass traps in some corners (also in the other side of the listening room) since I the reverberation time for low frequencies is a little high. There will also be some diffusion added to the wall where the speakers are, but limited. Apparently dynamics in my room are rather ok

I consider materials from Artnovion but also from WoodUpp

Cheers
Iver

@Thomas @Mark63

I received Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms by Floyd E. Toole last week. An eye opener indeed. Thanks Thomas!

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Capture

–> https://ethanwiner.com/basstrap_myths.htm

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I received mine also. Now I just need to find time to read/absorb.

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He misses out an entire class of bass traps: bandwidth limited pressure mode absorbers.

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On purpose, and he explains why.

I didn’t see anything in his article to do with any form of bandwidth limited pressure mode absorbers.

I don’t see anything saying how they work or saying anything about their performance characteristics - either their benefits or their drawbacks. He covers broadband flow mode absorbers and resonant “absorbers”, but nothing about pressure mode absorbers.

Indeed, it’s a shame. But I guess it wasn’t E.W.'s intention.
The whole point of the article is to emphasis the advantages and benefits of porous (velocity) absorbers in small rooms.

Unfortunately by missing out non-resonant pressure mode absorbers he weakens his whole argument in favour
of flow mode (porous, velocity mode) absorbers.

His argument is in favour of wider bandwidth of absorption than can be achieved with resonant “absorbers” - this is an argument with which I wholeheartedly agree; however the advantage is from the greater bandwidth, not the mechanism used to achieve this. This is the point I’m making. He gives the impression that the advantage is due to the flow mode absorption when in fact it’s due to the greater bandwidth, and this can be also achieved in other ways.
Bandwidth limited pressure mode absorbers can achieve useful absorbance over a relatively wide 3 to 4 octave range from lower bass up, whilst being about 1/2 to 1/3rd the thickness of flow mode absorbers.

Mine have a main absorbance from 35Hz to 350hz, with a steadily reducing effect to at least 500Hz before the characteristics become much reduced and more inconsistent, yet are only 450mm thick. I also have a design (which unfortunately I can’t currently complete) that will go from 30Hz to 350Hz (calculated) and with reducing effect up to >600Hz whilst reducing the thickness to 400mm.

Hi @Xanthe, you speak knowledgeably on the topic of acoustic treatment, do you know of a good ‘www. place’ to visit on DIY absorber solutions?

Unfortunately, it seems that the knowledge is distributed across a large number of sites… that said however, the first question is “What do you have now and how do you want to change it?”.

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My record collection acts as a diffuser…

Your dogs might, too.

They are there in case you ask to borrow one of my records. :wink:

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:grin:
I own two Basset Hounds, so mine don’t do anything…well, maybe they’re more like bass traps.

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Big hump at 49Hz and another at 100Hz, tempering both or either would be great!

I have had absorbers on the front wall behind speakers but put up GIK Alpha panels which are a combination of diffusion and absorption. From my initial testings I prefer absorption on the front wall and the GIK panels behind me. On the front wall I felt it got bit to lively so the focus was mids/highs and I lost the feeling of bass in the spectrum. When I move the GIKs to the back wall and absorption to the front it calms down a bit and I tend to think the music sound warmer which I prefer. Makes sense?

Long time ago on the original Naim Audio Forum there was a thread in relation to building a specific listening room and I think in relation to measurements of the intended room the Fibonnaci numbers & sequence were mentioned especially as to the “Golden ratio”. I just wondered how the Fibonnaci numbers were advantageous or conducive to an audio room?

OK, those are at relatively high frequencies (in terms of true bass traps at least)…

This bodes well for tempering them using pressure mode absorbers (i.e. with membranes, not just big blocks of open cell foam). Foam ‘bass traps’ usually only work effectively down to about 120Hz, so aren’t really ‘true bass traps’ - more like partial bass traps. Large amounts of foam may be able to help with the 100Hz, at the expense of over-damping the 100Hz to 300Hz range, but that will have little effect on the 49Hz - hence the need for membrane based based bass traps.

Those problems are fixable - expensive if you go down the commercial Bass trap route, relatively cheap if you make some DIY non-resonant damped membrane acoustic absorbers yourself. Be aware you’re still talking about severl square meters area of absorption to make any real impact.

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