New gear, Room issues with bass

[bdiament]

Hi Mihnea,

After finding my listening position and the position of the speakers, I have realized that in addition to the bass issues my room has also issues in the mids and mid-highs -- annoying reflections which render music with electronic guitars almost inaudible.

I am now considering building my own bass traps and absorbing panels as Barry suggested. I would open heartedly buy them all, but I cannot afford that amount of cash right now.

After reading various opinions on the Internet (mostly the Gearslutz forum for studio rooms/acoustics) I learned that almost everyone on that forum favours the standard panels (broadband absorbers) and corner traps to the cylindrical bass traps (like the ones made by ASC).

Did you have any practical experience with both designs? Which one did you find more suitable for corner bass traps?

I know that Barry recommended the cylindrical ones.

Thanks.

I think it a *very* good idea that you ask folks who have tried the different approaches and not just one. Hopefully the same is true of the folks on that other forum.

Ideally, you can try some different approaches yourself. That will tell you a lot more than reading 1000 opinions from others.
Have fun!

Best regards,
Barry
www.soundkeeperrecordings.com
Barry Diament Audio

[mayhem13]

......or you could approach it from a more analytical approach instead of trial and error based on the experiences of others. A placement position of a set of speakers will never be optimal for the entire range of acoustic properties involved......something will be compromised. No rocket or science of acoustics here...just the study of practicality in an imperfect world.

[Jsmith]

After finding my listening position and the position of the speakers, I have realized that in addition to the bass issues my room has also issues in the mids and mid-highs -- annoying reflections which render music with electronic guitars almost inaudible.

I am now considering building my own bass traps and absorbing panels as Barry suggested. I would open heartedly buy them all, but I cannot afford that amount of cash right now.

After reading various opinions on the Internet (mostly the Gearslutz forum for studio rooms/acoustics) I learned that almost everyone on that forum favours the standard panels (broadband absorbers) and corner traps to the cylindrical bass traps (like the ones made by ASC).

Did you have any practical experience with both designs? Which one did you find more suitable for corner bass traps?

I know that Barry recommended the cylindrical ones.

Thanks.

I find it surprising that you are having this degraded sound that it necessitates room treatments to even listen to it. Please don't think I don't believe you or question what you are saying. With proper placement speakers should sound relatively good, and not require room treatments. Room treatments will help to take them to the next level.

I believe Chris has very little to any treatments in his room, yet has good enough sound to review equipment. If I take out my few treatments, the sound is still very good. Putting them back in requires me to listen very seriously for the difference. It is there, but not immediate night and day.

[wgscott]

My room bass problem:

[HIFI]

Jsmith, my room that I wrestled with was one that, no matter what speaker I put in, ringed at higher volumes. It was described to me as comb filtering. Once I added treatments I was able to advance volume control and reduce the ringing sound. It was at that point the bass became full and powerful. I certainly cannot determine this is the same problem as the OP but his issues and descriptions sound too familiar to me.

I find it surprising that you are having this degraded sound that it necessitates room treatments to even listen to it. Please don't think I don't believe you or question what you are saying. With proper placement speakers should sound relatively good, and not require room treatments. Room treatments will help to take them to the next level.

I believe Chris has very little to any treatments in his room, yet has good enough sound to review equipment. If I take out my few treatments, the sound is still very good. Putting them back in requires me to listen very seriously for the difference. It is there, but not immediate night and day.

[Jud]

Jsmith, my room that I wrestled with was one that, no matter what speaker I put in, ringed at higher volumes. It was described to me as comb filtering. Once I added treatments I was able to advance volume control and reduce the ringing sound. It was at that point the bass became full and powerful. I certainly cannot determine this is the same problem as the OP but his issues and descriptions sound too familiar to me.

The OP's speakers look in the photos as if they have to be placed fairly near his walls. Also, I'm guessing that perhaps his walls aren't as sound-deadening as those we're accustomed to in typical new American construction (gypsum board backed with fiberglass or similar insulation). And finally, with smaller speakers and wanting bass, they may be turned up to the point that the room is being overdriven a bit. So all in all not shocking, but also not hopeless. Mihnea has proved very patient, persistent, and careful so far in his quest for better sound, so perhaps knowledgeable folks here can help him go a little further.

[Mihnea]

The OP's speakers look in the photos as if they have to be placed fairly near his walls. Also, I'm guessing that perhaps his walls aren't as sound-deadening as those we're accustomed to in typical new American construction (gypsum board backed with fiberglass or similar insulation). And finally, with smaller speakers and wanting bass, they may be turned up to the point that the room is being overdriven a bit. So all in all not shocking, but also not hopeless. Mihnea has proved very patient, persistent, and careful so far in his quest for better sound, so perhaps knowledgeable folks here can help him go a little further.

I tend to agree with Jud on this one, my room is made completely of concrete, no plaster walls with mineral wool behind them to help tame the bass and mids a little. Also, the room is rather small (16.4'x13'x8.5') and it limits the placement of speakers and of listening position too far from the walls.

If it rings, it rings, there's nothing you can do except accept it and try to find a solution. I know a solution does exist, it's just that I need to go the bare minimum with room treatment to keep my family happy!

[Mihnea]

I think it a *very* good idea that you ask folks who have tried the different approaches and not just one. Hopefully the same is true of the folks on that other forum.

Ideally, you can try some different approaches yourself. That will tell you a lot more than reading 1000 opinions from others.
Have fun!

Barry, the folks in the Gearslutz forum are mostly professionals fixing their home studios' acoustical problems. They have slightly different needs compared to the regular music listener. For them aesthetics come on a second place compared to sound quality.

But even considering all the above, I cannot fathom why every question on that forum related to cylindrical (tube) traps is being received with a big NO, NO by all experts there. Looking at the type of acoustic products those experts' companies sell I can only draw 2 conclusions:

1. The cylindrical trap design is less effective than the flat panel design.
OR
2. The cylindrical trap design (Jon Gale) has been patented by ASC and no one else is allowed to replicate it.

This is why I have asked the question to people who might have played with both designs and might know which design is more effective in a small room.

For me it's simpler to build a tube trap out of pipe insulation material, there's practically nothing to do but source the material, cut it and seal the edges. I don't even need to cover it with textile material for a simple trial in my room.

It's just that I've been reading so much about the other designs and so little about the tube designs that made me wonder.

[mayhem13]

Ok so the room is concrete, and your original issue was an area of inadequate bass particularly the listening position.....correct?

[bdiament]

Hi Mihnea,

Barry, the folks in the Gearslutz forum are mostly professionals fixing their home studios' acoustical problems. They have slightly different needs compared to the regular music listener. For them aesthetics come on a second place compared to sound quality.

But even considering all the above, I cannot fathom why every question on that forum related to cylindrical (tube) traps is being received with a big NO, NO by all experts there. Looking at the type of acoustic products those experts' companies sell I can only draw 2 conclusions:

1. The cylindrical trap design is less effective than the flat panel design.
OR
2. The cylindrical trap design (Jon Gale) has been patented by ASC and no one else is allowed to replicate it.

This is why I have asked the question to people who might have played with both designs and might know which design is more effective in a small room.

For me it's simpler to build a tube trap out of pipe insulation material, there's practically nothing to do but source the material, cut it and seal the edges. I don't even need to cover it with textile material for a simple trial in my room.

It's just that I've been reading so much about the other designs and so little about the tube designs that made me wonder.

Jon Gale's design is not exactly the same as ASC's patented design. Either way, there is nothing illegal about building traps for your own use. (We are not talking about starting a commercial venture.) This is especially true when one is not copying a patented design. ;-} Harry Olsen developed the idea in the 1950s.

As to the "experts" on that other forum, all I can say, as I've said before, is that the monitoring in 99% of the studios I've visited is not what I would call trustworthy and is a big part of the reason so many records sound so bad. This is also one of the main reasons why judicious EQ applied in the mastering will very significantly help most recordings.

I would also question those who say "no, no" with regard to cylindrical traps. Are they sellers of panels? Have they actually heard a room fully treated with properly designed, properly placed and properly oriented cylindrical traps?

As always, my best suggestion is to *not* simply take my word or anyone else's word for something *you* will be listening to. Try them all yourself (there are inexpensive DIY designs for flat panels and other types of traps too -- search "Jon Risch"). Visit places that use different types. Let your ears tell you what works for you.

Another one of my personal mottos is "beware the experts". ;-}

Best regards,
Barry
Soundkeeper Recordings
Barry Diament Audio

P.S. The fact that your room is concrete reinforces my earliest statements in this thread. Speaker placement, listening position placement and proper room treatment are what I'd concentrate on.
It is also important to consider the speakers themselves. (I believe the cables are getting blamed somewhat for the "message" the speakers are delivering.) Some folks like to use "complimentary" colors, using a "soft" component in a chain with a "hard" component, in the believe that they will "balance". In my experience, what really happens is the listener then hears both the "soft" and the "hard" -- two colorations instead of one. I believe in addressing problems at their source. But most important for you, will be finding what *you* believe.
Have fun!

[Mihnea]

Ok so the room is concrete, and your original issue was an area of inadequate bass particularly the listening position.....correct?

That's true, the first thing I noticed when I installed all the gear was the lack of bass in the area where the listening position was supposed to be, except for the armchairs near the rear wall where excess bass was accumulating.

Since this was annoying enough, I did not notice the other issues like reflections in the mids and mid-highs, which are more apparent only when some types of music are played.

[Mihnea]

It's interesting what I've found on ASC website in an old whitepaper by Art Noxon:

"Before we address this, let’s look at the alternative, a room without shaking walls. This might be a concrete room, similar to what is common for residential construction in Europe and Asia. If we have a room whose walls don’t shake, we have in effect, a racquetball court. The sound in this type of room is just about as bad as it is in a reverb chamber. Since the walls don’t flex, all the sound dumped into the room stays in the room.

The only way to get rid of it is to absorb it, using lots of giant bass traps. Personally, I’ve never achieved satisfactory success using acoustics to convert a dedicated, sealed concrete room into a high performance listening room, and I’ve tried…. However, concrete rooms that are typically residential are not so impossible to set up and get sounding good because some of the bas buildup is leaked out of the room through openings, such as windows and lightweight doors, open doorways, halls, stairs and even closets."

So while I am not completely doomed, there's much to do to get it fixed :-).

[bdiament]

...I would also question those who say "no, no" with regard to cylindrical traps. Are they sellers of panels? Have they actually heard a room fully treated with properly designed, properly placed and properly oriented cylindrical traps?...

Perhaps an even more important question is "How does their room sound?"
Ultimately, this (not anyone's opinion, including mine) is where "the rubber meets the road", isn't it?

Most audiophiles who have heard good systems and/or those who are familiar with the sound of live music would, I daresay, be quite shocked at the sound in most control rooms and mastering rooms, which in my experience, tend to sound like very elaborate *car* systems (albeit capable of much higher playback levels).

Looking at photos can tell a lot too:
See how many indiscriminately throw foam on the walls.
See how many place diffusors (or rocks!) right behind the speakers, thus *guaranteeing* all early reflections from that surface reach the listeners' ears.
See how many place "monitors" atop the meter bridge of the console, thus ensuring a cancellation-induced midrange dip at the listening position.
See how many use "powered" monitors (then try taking an external power amp and placing it on or near a loudspeaker and listen to the results of what vibrations do to amplifier - and hence, loudspeaker - performance.)
See how many place speakers at the front wall, *in*(!) the front wall or in the corners(!) and consider how to best ensure stimulation of the room's resonant modes.

Let *your* ears guide you. Listen to as many setups as you possibly can.
It will be a *very* interesting journey of discovery.

Best regards,
Barry
Soundkeeper Recordings
Barry Diament Audio

[Encore]

As to the "experts" on that other forum, all I can say, as I've said before, is that the monitoring in 99% of the studios I've visited is not what I would call trustworthy and is a big part of the reason so many records sound so bad.

Actually, I had had this suspicion for a while. Not that I've seen many recording studios, but I have been wondering how the sound from even the same record company can be so variable. Of course, if we're talking classical music, recording venue means a lot, but still ...

[firedog]

It's interesting what I've found on ASC website in an old whitepaper by Art Noxon:

"Before we address this, let’s look at the alternative, a room without shaking walls. This might be a concrete room, similar to what is common for residential construction in Europe and Asia. If we have a room whose walls don’t shake, we have in effect, a racquetball court. The sound in this type of room is just about as bad as it is in a reverb chamber. Since the walls don’t flex, all the sound dumped into the room stays in the room.

The only way to get rid of it is to absorb it, using lots of giant bass traps. Personally, I’ve never achieved satisfactory success using acoustics to convert a dedicated, sealed concrete room into a high performance listening room, and I’ve tried…. However, concrete rooms that are typically residential are not so impossible to set up and get sounding good because some of the bas buildup is leaked out of the room through openings, such as windows and lightweight doors, open doorways, halls, stairs and even closets."

So while I am not completely doomed, there's much to do to get it fixed :-).

I have a not very large concrete room, and acoustic treatments made all the difference in the room. The room went from having lots of various echoes, to having no obviously discernable ones. It definitely works, and you don't have to be an acoustic genius to get the basics right.

[mayhem13]

For the OP.....we can be pretty sure given the composition of your room that there's more LF gains available than the typical plaster/drywall space. That being said, two possibilities exist......

Your lacking bass is a pronounced cancellation induced null. This is most probable since you have been able to reduce the null by moving speakers around. Traps won't really help much here as they mostly smooth response by reducing modes or peaks.....of which you may or may not have.....but you certainly have a null.

Your lacking bass is inherent in your speakers response as the somewhat small ported enclosure begins its roll off. Most small bookshelf speakers rely on room gain to make up some of the difference. Large open spaces aren't any help to these systems....and IMO your space volume isn't what the Dynaudio's were intended for.

Now I would certainly set the speaker positioning for soundstage first, forgetting about bass response for now. Experiment heavily with toe in until you are happy with the tweeter response. Dynaudio uses a dome who's off axis response droops very quickly but on axis is slightly rising. You may find 10-15 degrees off axis works well. If this returns you to where you were before posting this thread....where bass was the issue and everything else was pleasing, you've narrowed things down enough to make the situation manageable. As of now, this thread and your criticisms of the performance are all over the place, and IMO seem to be worse than when you started.

[mayhem13]

It's interesting what I've found on ASC website in an old whitepaper by Art Noxon:

"Before we address this, let’s look at the alternative, a room without shaking walls. This might be a concrete room, similar to what is common for residential construction in Europe and Asia. If we have a room whose walls don’t shake, we have in effect, a racquetball court. The sound in this type of room is just about as bad as it is in a reverb chamber. Since the walls don’t flex, all the sound dumped into the room stays in the room.

The only way to get rid of it is to absorb it, using lots of giant bass traps. Personally, I’ve never achieved satisfactory success using acoustics to convert a dedicated, sealed concrete room into a high performance listening room, and I’ve tried…. However, concrete rooms that are typically residential are not so impossible to set up and get sounding good because some of the bas buildup is leaked out of the room through openings, such as windows and lightweight doors, open doorways, halls, stairs and even closets."

So while I am not completely doomed, there's much to do to get it fixed :-).

Are these guys kidding with this.....as a paper?.....racquetball courts...shake? This is a sad sad state of affairs for hi def audio with this type of reasoning.
I love the whole not leaking room thing......classic.

[Mihnea]

I have a not very large concrete room, and acoustic treatments made all the difference in the room. The room went from having lots of various echoes, to having no obviously discernable ones. It definitely works, and you don't have to be an acoustic genius to get the basics right.

Thanks, firedog. What did you use for room treatments (type of materials, not brands)?

[Mihnea]

Are these guys kidding with this.....as a paper?.....racquetball courts...shake? This is a sad sad state of affairs for hi def audio with this type of reasoning.
I love the whole not leaking room thing......classic.

Well, not sure about the reasons, but in my dealer's home (whose room plan was posted earlier in this thread) the bass was certainly not an issue. Although his room was also concrete, his front wall was doubled with plaster wall and mineral wool, so this might have helped with bass.

Also he has quite some space behind the listening position and a large space where bass could "leak" and not produce the buildups and/or cancellations it does in my room.

Could be that his bookshelf speakers have different specs, he's got Raidho C 1.0 or 1.1, not sure which ones.

[Mihnea]

Large open spaces aren't any help to these systems....and IMO your space volume isn't what the Dynaudio's were intended for.

The dealer's audition room is a bit larger than mine (has taller ceiling) and the bass of these speakers was flawless there. He had only the 4 pieces of Auralex LENRD I borrowed to test if they work in my room, installed on the front wall's corners.

He had echo/reverberations in the mid-highs as well, I tried the heavy metal stuff and it was not extremely pleasant either (better than in my room, but not very nice).

Now I would certainly set the speaker positioning for soundstage first, forgetting about bass response for now. Experiment heavily with toe in until you are happy with the tweeter response. Dynaudio uses a dome who's off axis response droops very quickly but on axis is slightly rising. You may find 10-15 degrees off axis works well.

That's exactly what I did last evening, I have changed the toe in a bit and it has definitely improved the soundstage. Although by removing the Auralex LENRD (had to return them) I had nasty echoes in the rear left corner and again the bass accumulation on the rear wall.

My conclusions were these:

1. I need some bass trapping in the rear left corner and possibly in the front corners as well.
2. I need to address the echoes (reflections) in the back of my listening position (the rear wall) or else will be listening to a church-like sound.

How I will solve those 2 points I really don't know yet, since I need to maintain a nice aspect of my living room. Cannot just hang panels or tubes all over the place :-)

[bdiament]

The suggestion that room modes result only in peaks and not dips as well is just not remotely correct.
Ditto for the suggestion that properly designed and implemented traps will not help.

And double ditto with regard to the dismissiveness regarding Art Noxon of ASC, who has probably forgotten more about acoustics than many are destined to ever know.

Best regards,
Barry
Soundkeeper Recordings
Barry Diament Audio

[bdiament]

Hi Mihnea,

...
1. I need some bass trapping in the rear left corner and possibly in the front corners as well.
2. I need to address the echoes (reflections) in the back of my listening position (the rear wall) or else will be listening to a church-like sound.

How I will solve those 2 points I really don't know yet, since I need to maintain a nice aspect of my living room. Cannot just hang panels or tubes all over the place :-)

I'd suggest traps in more than one corner - the effects are cumulative.
Also, in your room, with your speakers, it may not be the fundamental modes that are being the most strongly stimulated. If the speakers aren't reaching down very low, they may be stimulating the first or second harmonics of the fundamental modes, which would suggest treatment at wall midpoints (or quarter points) rather than corners as having the most benefit - if you are not going to go for a full treatment.

You've already heard the benefits of *some* treatment.
As to keeping the look of your living room, do remember that if you build your own traps, *you* can decide on the fabric with which to cover them. There are many attractive fabric designs available in both solid colors and prints. Building your own can result in much more living room friendly (and sonically better) treatment.

Something to keep in mind along the way.

Best regards,
Barry
Soundkeeper Recordings
Barry Diament Audio

[mayhem13]

Ok....so go ahead and continue with you regimen of trial and error with traps and panels and positioning as its working so well for you in your experiences and the OPs. Frequency response has nothing to do with final in room response I suppose as well. Welcome to the dark ages......later.

To the OP. If you would like to continue the discussions, feel free to PM me. Thanx for the chance to help you with your sound....I've enjoyed it very much.

Later.

[bdiament]

When you get a bit more experience, you'll find that room treatments (I don't suggest panels) are not at all "trial and error" but are a well worked-out science based on the physics of sound.

As I've said earlier, looking at frequency response in rooms, aside from making a few assumptions I've delineated earlier, is looking at symptoms and not causes. Room issues are time-based, not amplitude-based. I would suggest getting some software that lets you look at what is really occurring in rooms (such as the superb SpectraFoo).

To cleave to frequency response as the be-all, end-all is, as I've said before, to hold an elephant by the tail and declare it a snake.

And room modes cause only peaks and not dips?
Treatment will not "fill" dips because they are separate from modes?
"Dark ages" indeed!

The good news is that if you let some information in, there is much to learn.
If you don't, you are doomed to seeing everything in terms of frequency response.
(What time is it? Plus 1 at 100 Hz.)

Best regards,
Barry
Soundkeeper Recordings
Barry Diament Audio

[ckpiv]

Mihnea:

I have been following this discussion for the past 10 days. You are fortunate to be getting some great advice from some highly regarded CA members.

I have one thought I wanted to pass on. Is it possible for you to trial a different type of speaker from your dealer? It seems to me if you are fighting this setup for 10+ days to get acceptable sound you need to determine if it is all room based issues, speaker issues or a combination of both. If you could maybe try out a pair of floor standing speakers and see if you still have similar issues you would know its the room. If the problems minimize then your speakers may not be ideal for your setup. Just a thought. Good luck!

Chuck