They have their use and might be a god send for some systems.

My brother had a MiniDSP room correction something something in his system for awhile. It can help alleviate bass energy problems. It never sounded quite right. We both agree that using absorption to correct the bass energy is the optimal way to do it. I'd rather have a more uneven freq response that use a miniDSP type product. However, if I had a really bad peak at say 40hz I couldn't tame, I would consider it.

If you want to play both digital and analogue sources you will need an A/D converter for the analogue. Or get a unit that takes an analogue signal and then does the wizard stuff.

Issue is that it becomes the weakest link really quickly. I found making a filter with REW and loading it into HQPlayer or Roon works better. This only is a streaming and server option though. I prefer not to do this.

If possible getting some high "horsepower" bass absorbers is my first choice.

Any electronic room correction device is going to taint the music. It will lose/mask information from the source in the process.

John

Piesoman,
Place four 2x4 absorbsion panels one each on first reflection points of side walls and ceiling. Two 2x4 centered on back wall. One 2x4 on the front wall behind each open baffle speaker. Use a mirror and helper to find the points.

If your bass is good, no need to fool with the corners which is usally reserved for bass absorbsion using diaphram panels.

Good start.

John

This is the best room correction tool.

This was quite a long time ago, so may not relate to current amp models totally. But all else the same, when I changed from a SE34 to a Torii III, my room overloaded, the Torii bass overwhelming the balance. I talked with Steve, and he gave me good ideas for how to make low range diaphragmatic bass traps, and other pointers. With a fair bit of reading online as well, I also made some absorbers for mid bass, and for higher frequencies. Putting these everywhere I could without too much visual distraction in my living room, I used a full box of rigid fiberglass in this process and a fair bit of foam on top of some some of the absorbers.

Much better, and not wanting to impose more absorbers on my room, I started experimenting by-sound with EQ. I started by making a very narrow parametric EQ peaking at 10-12 dB and slowly swept it from bottom to top with bass strong music playing. This EQ was in Pure Music player software, so I was adjusting the actual digital files Pure played from my hard drive. No added hardware or cables made it a nicely transparent way to adjust EQ.

Then doing these sweeps again while playing a small selection of heavy bass recordings, room resonant frequencies as I met them  sounded hyped and unnatural, overwhelming the sound. In rare cases the 12 dB EQ bump did nothing apparent, implying a place the room was cancelling frequencies rather than accentuating them. Not many of these, I focussed more on the ones that were being amped up by the room, writing down those frequencies from my sweeps, including perceived intensity of each.

The rest of the spectrum seeming quite good with my particular room and absorbers, but I did find some minor resonant frequencies in the mids and highs also. Though much less extreme, I noted them too.

Then I carefully attenuated peaky frequencies using very specific, quite narrow parametric Qs. Going further by carefully locating the worst peak frequency of each noted area, I then conservatively found an ideal level of attenuation by sound, and the best width for the EQ. The same method applied one by one to all problem frequencies, the remaining room modes absorption had not fully resolved were very musically improved.

Bass the worst, several bass area cuts were ±5-6 dB, and I found I could further improve on this with a few general bass self cuts of a dB pr two, finally putting in a big bass shelf cut (-18 dB) from 16-18 HZ down.

Other than low bass, EQ adjustments were much less intense, usually from plus or minus 0.11 dB, to 1.57 dB, and only a few at 1.57 dB. And these too were quite narrow, most 0.1- 0.15 octaves wide, with a few around 0.19. So above low bass, I used mostly very small EQs, but these were very nice refinements, especially collectively. Very small adjustments indicating to me that my room was quite good through most of spectrum, still, the “real” sound emerged notably from these little changes, so doing the work was well worth it.

Using this method, my first adjustment run was highly effective, the sound getting better balanced, faster and more musically complex by chilling the most aberrant room-accentuated/created EQs. Then, over time, as odd sounding problems showed up with the occasional recording, now and then I would do another sweep to locate trouble areas, but mostly just played with predetermined EQ widths and intensities.

Hearing more altogether as things got less masked by excess frequencies, subtler imbalances, lows, mids and highs were better revealed, allowing further identification and refinement with new EQ adjustments. All along I was seeking sound I thought was balanced, natural and more real sounding, and doing this across recordings, going too far, or not far enough for good balance across recordings also became more obvious.


Having enjoyed playing acoustic and electric instruments much of my life, and loving to work on things like tuning braces on guitars, or adjusting violin sound with sound posts and bridge tuning, I felt like I had developed relatively believable discernment, so trusted what I heard.

And generally not trusting our immature tech over very complex and advanced human perception, I intentionally did not use Room EQ Wizard or the like. I did not want to get stuck on what was measured as "right," preferring to find it by what my body/mind "measured." I also thought this might be a better way to balance frequency issues considering phase/time issues being inherently different when amping up or attenuating different parts of the frequency range.

I still use this foundation many years later, and as my system gets better, sometimes I start noticing places I can improve, and usually can refine whatever I am hearing by casually fine tuning over a few days on various recordings.… By adjusting a little EQ bump or valley up or down, often by only 0.01- 0.07 Db, and/or by moving it a touch, or widening or narrowing the Q with slight adjustments, I can refine as needed. Over time, refining remaining room issues with relatively subtle EQ for the most part, it just sounds more right, more balanced and alive, faster and more resolving.


While exploring fixing my room issues, I found other helpers....like Marigo resonance damping dots, very good at subtly and progressively reducing speaker driver resonances in musical ways....tightening bass and increasing space and resolution due to solving resonances that cause loading and smearing. Also I learned to carefully tune the speaker plinth space, adjusting the passive bass from the MG944s and HR-1s to sound best. And this led to exploring internal damping more, further clarifying the tone across the spectrum, but particularly making bass more natural, full but tighter, so more impactful with better leading edges and decays. I found Schumann Resonators, ending up with one made by Kemp when they were on sale... and liking it, later got another when on sale. Can't say exactly why they work, but in my setup, optimally set, they somehow make the room accept musical frequencies from bottom to top more openly, less smeared, revealing more fine detail and space, and thus a cleaner more complex sound with better atmosphere and soundstage. Here, it sounds like it somehow makes frequencies more coherent, less interactive with one another. Also I discovered ways to use tumbled crystals of different types and mixes. Functioning like a filter, among other things, they can apparently draw off noise energy and convert it to heat, increasing clarity and dynamics with careful use and placement.....Some rock and metals are deadening, and some awakening, so I continue to explore this, always discovering new ways to improve these "filters."


Also, like Lon sometimes talks about, I too have found you can do a lot to help resolve room sound issues by making all the system parts more resolving and musical. Roughly, the way I see it, one reason this works is that the less smearing and aberrant distortions and frequency imbalances coming from the speakers, the less there is for the room to mess up further.


Within all of this, I have been really careful to keep what I think is a fundamental baseline of full spectrum balance so that I can trust changes I make with system parts or modifications. And so far, I feel like I have been pretty successful in that.

Each time I listen to Decfest, though not the best comparison being streamed, heard through my headphone setup, and pre adjustments being played with during the Fest.… But within this, consistently, my sound seems to be a lot like the most listened-to setups each year, and better than the rest.

Several years ago, I was able to listen off and on throughout, and my favorite sound was the Mystery amp through the el Caminos with tape as source. The el Caminos, fast and musical, and tape resolving, this was very close to the sound in my setup with my tuned up computer/DAC, seriously adjusted amps, and modified HR-1s.

Then, a few years ago, I think the last Fest, my spectral balance and speed here sounded in between the two most listened to setups I noticed that year. Closest to the 25th SE84 playing through the original Big Baffles, my sound was a little softer and more atmospheric to me. Those super hardwood big baffles were a little overstated by my tastes, so my sound was not as dramatic as them, being close, but having more of the atmospheric magic of Bob's new HR-1s driven by the Mystery amp. To me that HR system was also a little overstated, too “warm,” dark and slow for my tastes. So I found it interesting that my sound had some of the sweet atmosphere of the HRs, while also being faster and clearer, in ways more like the big baffle/25th sound. In the middle somewhere, I figured I was on a good track.

In both years, if my headphone interpretation of the streams was relatively accurate, the biggest difference was that my setup was more resolving of the finest details and spacial information. But I have been tuning with this in mind for many years, so this made sense to me. The upshot though, these listening comparisons supported trusting my perception as I tune my system/room, while implying that whatever I was doing to hold a realistic balance intact as I change and modify things was working pretty well. What a trip!

Hey John. I agree, we could refer to taste, and I recognize this as real, but I also am beginning to think we may tend to give personal taste more weight in our audio discussions than it deserves, especially when those discussing these things are long lovers of music, and experienced audio heads and listeners.

I am thinking that though there are variables in how our body/minds perceive sound, my guess is that if we are basically healthy, what defines the sound we like might fundamentally come down to basic human perception and discernment having pretty defined parameters for what feels real.  ....I am thinking this is based on how we evolved, how we are made. And though the wild cards of cultural "training" do alter our senses of "reality," my guess is that our basic needs as human beings are at the foundation of most of what makes music feel right.

To illustrate this idea, why do really good guitars, though all different in some values, why do the great ones sound complete spectrally, and in nuances... and to most who hear them? Or violins, or pianos, or drums. Certainly there exists a range among great instruments, but the great ones do it all well within that, and enjoy a strong consensus agreement among serious listeners.

So even though each has complex variations of tonal and timbral emphasis, all the greats sound complete, and I am pretty sure that is based on basic human makeup. Makeup that also defines choices in how we make things sound good... I think decisions are most based on how good sound feels to our body/minds.

And I would say the same holds true for fine audio in the home. Consider audio shows. Though a lot sounds bad due to rooms, etc, there is almost always a strong consensus among judges and listeners, which room, and which components are "best." I guess this agreement is based on our human makeup defining what qualities of sound we tend to like, especially if we are one of those who dig in.

So to me, getting my system room to sound "alive" and "real" is the goal...and it is far from all ears...music vibrating our spaces and body/minds. With all perception and discernment, I seek a musical experience like being in the room where the recording was made....or in fact, in many cases better, which I think these days we are quite capable of with care and dedication.

At the same time, as I imagine you also notice from all your explorations, "real" music has vast, and very specific perimeters and balance, and it does not take a whole lot to throw it off from feeling "just right." So those of us deeply dedicated to discovering the depths of great audio at home, we listen and learn, experience and learn.

This is part of what led me to trying over time to develop a system/room that is really good across recordings. With recordings qualities so variable, this clearly is challenging. But the trap of making a system that sounds great with the best recordings only, is that it is harder to discern problems with great recordings, and easier to get off track.

And every year it becomes easier to use the broad reference of many recordings to find the balance of beauty. With tools people like Steve have developed, tools that can sound natural, sweet and revealing, while having a great deal of tuning flexibility with tubes, feet, power, cables, gain tuning, etc, and finally, especially with gain riding, it gets easier to get great sound across more recordings.

Interestingly for me, as a system/room gets progressively more nuanced and refined, the "holy grail" gets more nuanced and refined. By now, my amps and speakers have most parts and wires upgraded individually and progressively by sound. Also most of my cables were made and tuned by sound. And wildly, this happened over many years, and with each little step, there was a notable improvement on something that had started great. Yet as I get further into approaching grail territory, the grail keeps poking its head up, out there seducing me, but showing itself as even more complex.... touchable, yet also remaining elusive. Amazing process to me, so far, as the music grows more captivating, I also find more to improve toward an ultimately engaging experience.

And yes, my source could no doubt be better, and I definitely think about it...maybe dig into a really good ladder DAC is the latest. But then I listen to what I have and am amazed... sounding so good that talk of analog versus digital has had little relevance to me for quite a long time. This is in part because the source is finely tuned, from the power, to the computer itself and its software and setup, to hard drives, to cables, to a modified Singxer USB convertor, to having seriously modified my DAC... then a ZBIT and CSP3.... My front end is really good to me, but I am looking at it, as everything else. It is all a big puzzle I love to play with, a more enticing musical experience always giving sneak peaks!

Quote:


Corner panels as described above will do little to absorb bass. The bass will just hang in the corner as always. Some bass will be absorbed by the absorbent material in the panel.

A better way to utilize material in the construction of a panel and add some would be to rip the furring at a 45 degree angle and attach it to the wall vertically coming out lets say 2' from the corner. Add the absorbent material, preferably rockwool board, between the furring. Then attach a spacer strip creating a 1/2" gap in front of the rockwool to the outside edge of the furring. Cover the the whole assembly with 1/4" plywood and finish to taste.

The idea is to resonate the plywood with the standing wave and excite the enclosed air in the cavity therefore vibrating the rockwool fibers creating heat removing energy from the wave. This all can be tuned to the offending standing wave frequency by the type of outside panel, thickness, weight and depth of cavity. A corner bass diaphragm absorber has an advantage of eliminating standing wave frequency's over a wider range because the depth varies. Although centered on the average depth, the peak absorption bandwidth is wider as compared to a constant depth enclosure.

I think the plywood helps in other ways but not sure exactly how. Maybe someone can elaborate.

I placed two of these panels as describe above in the back corners of the Chariot. The room had a 58hz standing wave issue that prevented hi power listening with a sub in HT mode. Now I can turn it up without the boom. It works as simple as that.

John

thanks Jbzen

what if i don't engage in "hi-powered" listening, and not with a sub cranked up and system in home theater mode?

my single sub is a refined, low-powered 150w rms / 400w peak. i chose it very purposefully.

i listen mostly to classical music.....about 85db max.

it sounds like you have a very different purpose-built system than i do.

The Master Handbook of Acoustics is a invaluable resource but yes your eyes will glaze over reading it.  It's best used as a reference.

Mr. Deckert has written white papers on the subject of room tuning that have been very helpful to me.  I believe Steve said to attack the bass freq. first.  Also, look up some of Lonely Raven's posting on the subject.

Room treatments need not be expensive or ugly if you have a small amount of DYI skills.  I consider my efforts of building diffusers, absorbers and bass traps to be the foundation of my total system.  In fact, my total expense for all of it is lass than many of the electronic components.

The bottom line is "A well tuned room can make a very inexpensive audio system sound really good".  Conversely, a very expensive system can sound like crap in an untreated room.

Aside from the Handbook and Steve, and Raven, among others, Dennis Foley at Acoustic Fields has done a lot of instructional videos as well as written things in his blog, etc. https://www.acousticfields.com/videos/.

I guess most of us have looked at this over time, but being so complex, I thought I would try a general overview to bring it into some sort of perspective.

If you visualize a sine wave.....illustrated with a flat horizontal line in the middle, the wave starts at the line and gradually rises to a peak, then gradually back down to the line. Then it continues down creating the trough side of the wave, and finally going back up to the line...This up and down and back up pattern illustrates one wave cycle.

Then, the higher the frequency occurrence of cycles in a second, the higher the "frequency." Cycles per second, expressed as hertz, 20 HZ is 20 cycles per second.

The speed of sound being 1130 ft/sec, within this, a cycle at 20 times per second (20 HZ) results in a much longer wave than one at 1000 times per second. A 20 HZ wave is 56.5 feet long! Where a 200 Hz wave is 5.7 and this is important in terms of room modes and absorption.

Basically, in a smaller the room, these waves reach reflection points and bounce the other way more quickly, setting up lots of potential for reflected overlaps that cause amplification and attenuation of the frequencies, off-balancing the sound. Especially low frequency waves are problematic because they are so long, and so powerful, so harder to fit into small spaces, and easier to create room-based frequency changes. And room dimensions, surfaces, and how speakers are placed, cause the waves to interact differently, thus all the attention to speaker placement and toe, and room treatments.

Looking "linearly" at a given frequency only...the way I understand it, room-based amplification happens when two reflected waves overlap with a similar peak and trough pattern. When the peaks overlap more symmetrically, the peaks build on one another, amplifying the frequency. And when peaks and troughs of two waves of the same frequency are directly opposing one another, the valley of one exactly opposite the peak of another, they cancel each other.

Then it gets crazier... attenuation or amplification stronger with wave overlaps more perfectly aligned, and less when they are a little less aligned, but still changing the intensity. And different frequency peaks are apparently able to interact similarly, so different frequencies can mix in exaggerating or attenuating each other.

Then, the rate at which the reflected frequencies reach our ears compared to the direct sound, especially with reflected frequencies being “EQ’d” by the room, reflection issues effect our perception of frequencies and spacial placement, and therefore our musical experience.

For most rooms the long bass waves can't play out fully, and rather than letting them “bounce of the walls” causing overlap with build up and nulls, we try to "trap" them. If bass frequencies build up too much due to different frequencies and reflection boundaries, we get boom, thickness and muddle, robbing bass of completeness, speed and impact, while often overwhelming the mids, and/or leaving the room seeming bass shy. 

So people came up with speaker placement and toe tricks to make reflections less interactive/strong, while taking longer to reach our ears. Related, "first reflection" treatment became primary along with bass trapping. The room carefully supported by just-so absorption and diffusion catching or dispersing negative reflections, negative room effects can be mitigated, empowering a more engaging musical experience. And thus all the talk about room being so important.


Looking at “trapping” bass with absorptive materials, a 40 Hz wave is 28.3 feet long, a single wave cycle so long it is comparatively flattish as it goes through absorptive material. A more direct line creating less friction with the absorber fibers, the transformation from sound to heat is less. So bass waves being so long, we need a lot of absorption material thickness to do much. This makes denser fiber boards useful. With rigid fiberglass and rock wool, the sound waves interact with many more fibers than with less dense things like wall insulating fiberglass, and foam even less. So use of dense absorber material is about denser layers of fibers creating more conversion of sound to heat with less thickness.

But even so, using absorption material alone, it takes a lot of thickness to do much low down. So rather than filling up the room with absorbers, people make them more efficient, leading to diaphragms, space between absorption pieces, and/or between the panels and the wall… More material thickness catches more of the waves, and air spaces between and behind panels are meant to allow the wave to keep up some speed and therefore more friction/absorption when going through the panel fibers. With space behind, the bounce off the wall projects the wave back through the absorption panels, increasing the effect. And if the air space is in corners, the trajectory of the wave after an angled bounce is meant to cause its reflection to go back through the panel at a stronger angle, so more interaction with the fibers, more absorption.

Which leads to diaphragms. If the absorber surface is all absorptive, it will attenuate easier-to-absorb higher frequencies as well, so how to create enough absorption for bass, without killing the mids and highs is a consideration. This also introduces bass traps that integrate reflective surfaces, and diffusers on the face.

To focus more on bass, diaphragms are designed to resonate mainly with narrower bass frequency ranges. The diaphragm, absorbing, resonating, and pulsing those energies through the absorption material, seems it can increase the sound-to-heat transformation in that range.

So a spacer like John described for his corner traps, separating the 1/4" plywood and the rock wool, allows the plywood to act as a "diaphragm." Also, it seems diaphragms can help retain and bounce sound energy back through the rock wool as long as it stays in the "trap." And density/thickness of the diagram influences which frequencies it resonates with, so which frequencies it most traps.

Also, by using plywood panels for the face, the surface is more reflective of frequencies it does not resonate with, so can be a tuning mechanism for trapping bass, while not deadening the sound by over absorbing mids and highs.

And finally, at least the way I learned it, it appears that if a multilayer diaphragmatic absorber is sealed, air tight, with integrated spaces of air between multiple absorptive panels of rock wool or rigid fiber, it can more powerfully “absorb” the frequencies defined by the density/thickness of the diaphragm. It seems gradually dissipating the waves through more layers of material, it can be more effective.

Seems a lot of companies use diaphragms of mass loaded vinyl rather than different thicknesses of plywood, something I have not tried, but would like to know more about and explore.

I hope I got all that with relative accuracy.... and at least I hope it helps conceptualize the issues and solutions.


But to further address your question Piezo. In small rooms, with space restrictions for bass traps, and with increased bass handling issues, it seems it is relatively difficult to overdue bass treatment, especially using reflective diaphragms like John suggested. So, though amplitude is another part of all this, seems to me you don't really need to be playing big bass movies, or trip hop, or rap to benefit from finding and treating your worst bass frequencies…

Quote:


The resonate panel's weight per square foot has a direct correlation to resonate frequency of that panel. When calculating the Charoits it called for 3/8" plywood in the space allotted. 1/4" hardboard was substituted with the same result.

Quote:


That stuck and made me wonder! This video explained it.
https://animagraffs.com/loudspeaker/

Piesoman, glad you are getting good solid advice on your room.
The corner bass absorbers for my room measure 28" across the resonate panel and from the corner take up around 21" of wall space on one side 20" on the other. The side walls are canted at 5 degrees creating the difference. The side walls are about 20' long and back 16' - very little space is taken by the absorbers.
There is another standing wave around 80hz that calls for a panel 14" across and 10" of wall/ceiling space on each respective side of the absorber.

My point? Every room is different and so are treatments for such. Please don't get caught up with my treatments as you embrace yours. A corner panel might not take up as much room as precieved...3 square foot total floor space in my case.

Best
John

great post, will. i totally get it. a very small room like mine can be made to sound much larger, much more spacious given the right treatment application......one general truth about this is that it takes ALOT of treatment to "get there". the online calculators say like 12 or 13 panels for a 10x12x8 room, which of course is just a guide....but it gives an idea what we're talking about: significant.

that said, and as you say, an iterative approach is the start of the elixir: [1]corner bass [never will be anywhere close to perfect especially due to small room vs. wave length] + [2] at least moderate absorption AND diffusion.....i now understand one needs to treat 25% of the wall space at a bare minimum, preferably about 35%. that's ALOT of treatment! But I'm committed because I've recently realized the cost of the materials to do this is pretty inexpensive via DIY approach which is NOT hard to do.......if this stuff was all purchased commercially, 25-35% coverage would cost a real fortune.

- brad

I just got an email reply from one of the two sources I've been waiting on, PI Audio Group. Here's what they recommended:

1. 1 diffuser on either side of my audio rack placed vertically on the wall behind it [total of 2].

2. 1 diffuser placed horizontally over my audio  rack

3. 1 diffuser on the ceiling at the first reflection point.

4. Triangle traps at each upper corner of the room. We have been working on developing a triangle trap for this very purpose. I have some here and would give you a very good price for you to try them out.

5. 2 tube traps behind your chair to control the bass. [note: my chair is about 3 feet from the back wall and 6 feet from the speakers].

I will becalling Greg today.

No side refection treatment does seem unusual, but other than that, this PI arrangement does not surprise me much. From these recommendations we don't know yet how the corner traps and tube traps they recommend are made either... and how much absorption is active above bass. My experience with PI Audio is with Dave Elledge, and impressions from that are that he has been exploring the finer/subtler aspects of affordable audio a long time. Also I think he is creative, and can be pretty innovative. So I look forward to what you hear with your talk.

I made my last post before seeing gsanger's, and I think that post was a good pointer. For me, over-deadening would be a real worry, preferring a pretty live feeling sound myself. And in large part because of how my room is made, I don't have experience with lot of absorption, so can't be specific about what might be too much, but hopefully my story will help.

We have plastered adobe walls made with irregular adobe bricks. Traditionally made, the walls angle outward as they rise, so are off-plumb, and the plaster is somewhat smoothing, but intentionally not fully flattening the irregularities from the adobes. So the walls look flattish, but have very irregular surfaces with loads of small angle changes. Also, angle changes at "corners" are soft and not altogether square, and some walls in alcoves and partially open room segues are actually angled; brick on sand floors are also pretty irregular; lots of log beams with rough wood ceiling boards with gaps; tar paper above with 12" of fiberglass on it, then an airspace before a slightly angled "flat" roof with 4" of foam on top; lots of African sculptures all around; multiple semi-open room segues; some rugs and living room and dining room furniture....

I don't know how this initial setup relates to technically arrived at diffusion and absorption parameters when applied to flat walls, floors and ceilings. But with mostly pretty "live" surfaces, by sound, there is clearly a lot of useful diffusion and absorption, just by the way this house was made.

Then when I made bass traps and other absorption setups for different frequency ranges, I put them wherever I could without too much aesthetic compromise... But relatively speaking, with alcoves integrated in folksy adobe design, I had a number of good places to tuck in rigid fiber boards. Nowhere near the high percentage of wall 12- 2x4' panels would make in a small room though, and I recall reaching a point where I thought I was approaching too much added absorption.

Where I am going though, because my room does so much on its own, I don't have experience with a conventionally built small room. But conceptually, filling a room with absorption sort or gives me the creeps. And I have heard stories and heard music room videos that seem to corroborate that habitual use of lots of absorption can sound sort of accurate frequency balance-wise, but not necessarily so accurate in terms of natural/live sound.

Will, you got that right. Dave told me the dangers of over absorption on the walls, and he said exactly that the diffusion is necessary to keep the room alive. His plan for me is to maximize the liveliness while keeping all the unwanted, frequency smearing mid-upper frequencies to a minimum, and tackling much of the lower frequencies.

He told me when I'm done, I'll never go back because what I've been used to all my life will suddenly be extremely, irritating to experience.

Lonely Raven recently told me that we're all so used to living in our drywall boxes all our lives, that its a real radical change to actually address a room for acoustics.

Those online calculators are fucked up.

HK,

That's cool....is Eighth Nerve still in business?

Dave Elledge was instrumental in the design of the Charoit. I have not talked or seen him in 20 years. Good to know he still in the biz. Quite a character that will not steer you wrong.

John

Guys, thanks for the vote of confidence on Dave. He really was great to chat with. He rattled off alot of stuff while reviewing again the photos of the room i sent previously. I was feverishly scribbling as much as I could, asking questions.

Will, thank you, and I will report on my conversation with Dennis Foley at Acoustic Fields in this thread.....this Thursday afternoon.

Brad

Hey Dennis,

Sounds like a really good setup!

I wonder if you can describe the big bass trap in more detail, or do you have a link with plans?

Thanks,

Will

Thanks Dennis. That is a good story. Very pleasantly inventive! And glad it works so well.

I am getting it I think, but just trying to get a sense of why is works so well. Do you think it is basically the foam width doing most of the work? What part do you think the outdoor carpet plays?

Can you clarify "completely covered everything with outdoor carpet?" Did you cover all the wood underneath the frame and on the outside before putting on the mattress.? Did make a skirt with the carpet, running it down the sides to the floor?

And are you referring to the really short pile "carpet?"


Sorry for all the questions. Just wanting to understand so I can put in "brain storage"in case I need something some day using the same basic ideas.

Thanks,

Will

Palomino, your room treatment journey is legend around here.  However you did have the help of Raven.  Or, was it the other way around?

I freely admit that your skills at building diffusers far exceed mine.  For a long time I have been in hopes that Raven would get to the position of being able to sell some of his styrafoam designs.

I taught Raven everything he knows

He and I have experimented with various builds over the years.  I thought about trying to commercialize the QRDs, but I'd have to invest in a CNC machine (and have a place to set it up).

I don't think I have $1,000 in my room treatments yet.

Sorry Will, I missed your last post.

When I built the bed frame I thought it looked tacky.  Being the type that likes to use stuff laying around.  The outdoor carpet was left over from another project.  I went to work with the pneumatic stapler and covered everything (top and bottom).  I could have painted the frame but I do not think it would have worked as well and it looks good to me.

The idea is that the bass frequencies sneak under the edge and get absorbed.  I'm sure that the memory foam contributes.

The idea for the design came from Steve when he built his in his garage on Spring St. in Peoria.  This was prior to them moving to East Peoria.

There are many ways to skin a cat.  Just don't tell Steve I said that.

Dennis

Interesting Dennis. Yes lots of different cats around! Thanks.