Axiom Home Page Forums General Discussion Technical Questions Understanding Graphs, roll off and M100 querys

Ha ha ha ha!!! Nice. Yup. The next door beyond that is metal sealed door into garage.

Hmmmm. So maybe my initial volume calculation was correct ? I’ll remeasure. But I guess the bottom line is I can classify it as large so it doesn’t really matter in the end. I don’t think I’m in any danger of over pressurizing the space.

Ideally a pair of m100 with an Ada 1500 is all I need to get what I’m chasing.

Closed Door = Not coupled.

Heavier door the better. Ideally same STC as wall assembly in room.

Worse issue than additional cubic volume to load is random RT60 behaviour or echo from adjoining space reflections heading back into the room.

Does the time allowable for rt60 increase as the room gets larger? There must be a point where you can’t effectively reduce rt60 decay to the same levels in 2 very different room sizes, say a 2500 cubed room versus a 8-9000 cubed room.

Or is the desirable rt60 standard across the board regardless of room size? Say less than 0.5 ?

( Please correct me if anything I’m saying here is incorrect! I’ve been reading about this stuff but my understanding is superficial at best….).

I guess the real question is what is the standard and are they realistic?

Yes, as the room gets larger rt60 target times increase.

For living spaces you are targeting 0.45s on the long end to 0.2s to shortest time.

In a large room the longer time. In a bedroom 0.2s.

In a theater or 2ch room around 0.3s.

Measure by popping a balloon and using rt60 tool in Audio Tools or REW.

Carpet, window coverings and plush furniture advantages for sure.

To make it easier on you buy this book:

https://www.amazon.ca/Handbook-Sound-Studio-Construction-Recording/dp/007177274X

Includes everything you need and more.

Thanks Trevor. Super helpful. I’m starting my planning for our basement listening / media room. Hoping to start the build in the late spring after my work season ends. I’ll buy the book for sure. I’ll be doing the planning and design in between work projects over the winter. Looking forward to it.

Our living room is also still an ongoing work in progress. I think the media room might happen faster from a ground up build!! ( that’s the difference between me deciding on the media room and my wife deciding on the finishing of the living room!).

The rt60 will be a way bigger factor in the living room than the basement me thinks.

Maybe the quickest project will be our bedroom. Should be straight forward. House is finally painted interior so we can start putting our belongings into everywhere and making things normal. It’s been a moderate road of deficiency’s to get things looking good in the whole house.

I’m inspired by 2x6 with a dedicated system in every room in his house seems like!!

Trevor recommend both the book and AudioTools to me a while back. I can 2nd both.
Of the books I've looked at this was the most concise and most practical one by far. Wish I had it when I was first planning my HT.

AudioTools also seems to be a really good app. I have not used all the tools yet but so far I'm happy. AudioTools come with a minimum set of plug-ins. All the others, some of which you'll want, are ala carte.

Instead, I bought AudioToolsMax which is AudioTools with everything enabled (including anything which comes out in the future). It was a bit pricey even on sale (think the sale was something like 30% off at the time). I justified it because it had tools not only for room measurements but a few others I knew I'd need sometime in the future (like testing THD and noise).

One Note: Audio out on the newer iPads requires some sort of interface now that they no longer have a phone jack out. I have an older iPad I'm keeping around which is good enough for room tuning.

Another comment on the specs of the m100....I was comparing the m100 crossover points to the LFR 1100 passive and LFR 1100 Active ( being their big brother and all) and the specs show them crossed at 200hz and 2k...so that must be the current state of affairs for the m100 v4, standard and wireless. Unless theres a good reason to cross the wireles version differently.

Specs are kind of a starting point ... they never quite tell the whole story and are often misleading. Even so they are important ... so ... that said ...

I'm never sure about the specs and graphs here ... I think Axiom often changes stuff and then drags their feet on updating the specs on it. I understand it from a engineers point of view ... I did the fun/important stuff ... I'll take care of the getting/updating the graph and number stuff later ... never quite getting to it ...

From a marketing/sales perspective the specs and graphs are what people obsess over ... I mean to the point of insanity ... on paper a db of SPL or S/N can be the difference between buying your product or a competitors ... even though in most cases a db will not make an ounce of difference in performance.

But still, it's important that they be right even just to know which speakers in the Axiom line up you might be interested in.

One one hand, It's kind of what I like about this outfit ... more engineering minded then marketing minded. On the other it's sometimes a bit frustrating to be trip'ed up by an out of date or misleading spec.

Hey thanks rrlev. I’m not obsessed about it so no worries there. I’ve been comparing more out of curiosity and learning. Trying to understand the graphs better by looking at the graphs and frequency response and impedance curves. I think what you say makes a lot of sense. I totally get it from operational point of view, who cares if everything on the website isn’t totally up to snuff, the engineer and internally they know everything is as it should be, good enough. They know they have great products.

However, its more about how it looks overall to the customer looking in. Details really count to some people and other industry’s wouldn’t tolerate it.

I agree, a db here or there don’t matter at all, +\- 3db right!?:)


And I totally agree, I like how down to earth the company seems and not entrenched in “ audio politics “.

I just spent a week of on off music/movie sessions retuning my theater with Dirac after upgrading to M5OW surrounds. Many filters were tested using their 17 point measure process on a PC.

In a fully treated room, 1db changes in the vocal range are very audible and can make or break the realism of playback. I found that tweaking things in room with Dirac was far more relevant than what speaker was deployed.

The most important spec. aspects are power handling, distortion, dispersion and bandwidth. The rest can be tweaked these days using dsp with results that fool the senses in room.

Anechoic graphs are a great yardstick to compare products. These days you can make pretty well any speaker sound as you like with DSP barring pushing them into distortion while tweaking. -Not an issue for Axiom products.