Redirecting bass frequencies

Try and do one thing at a time so you can evaluate any change that may occur. If you take the same path as me,I wouldn't add any absorbent material until you have completed the changes in geometry. You may find you need no other fixes. Much of what I have done is an extension of direct coupling all of my audio components instead of trying to isolate them. I am trying to redirect the acoustic energy and sound pressure instead of diminishing the dynamics thru absorbtion. Tom

Tom's idea is great and if it is properly realized, it sure looks like it could be an advantage over converntional room treatment such as absorbtion where latter could definately be too much of a good thing...

Thanks Tom, interesting ideas that could be put to use in many ways...your thinking outside the box buddy!

My room is dedicated and was built by my son and I after I retired...I am going to kick your ideas around, as I am also doing with the room treatments at this time.

My room measures very well even with no treatments, but.. as I am also a long time tweaker and not just an audiophile...improvments are always part of the hunt.

Dave

Tom I think you are talking exactly about what I am looking for sonically. I will think about it. I can just smooth out those corners and see how that will change things. I'll start with that.

Yes..but you have walls, floor and ceiling those are the same. You could make panels to fit that could be moved around.The panels can be made and covered to compliment the room.. Really the difference is, panels that are designed to absorb vs those that are designed to redirect energy. Tom

thanks Tom. I had to read this few times to better picture everything you did. Yes, sounds good, unfortunately I can't do all this as this is a living room as well. And it's an appartment. If I start this here, my land lord will go off like a missile...

Thanks for asking..I am not a engineer just much of a experimentor. Been in and around audio for thirty five years.Much of what I have found I have applied to my own room over the years, not all at once but a little at a time. My Dunlavy SC4's as good as I could make them never did the bass thing well in my room at my listening position. Position was dictated by other fixed obstacles and my preference for wall to wall soundstage 21.5 feet by 9 foot...As cool as all this was I had a midbass suckout of 6db at 60hz only at the listening height of 38inches. What I found as I moved the mike up towards the ceiling the bass at that frequency began to fill back in. Can't hang from the ceiling and listen...well I guess I could..So I surmised the problem maybe ceiling related and the fact the Dunlays have 2 woofers that may load differently to the floor and to the ceiling based on their differences in height. Having met many years ago Peter Snell and remembering that he had patents on baffle design and the way they load into a room ,I made a ramp to sit upon the top of my Dunlavys. This ramp went from the top of the speaker to the intersection of the ceiling..With this ramp in place I got 3db of my 6 db suckout back..Also the stage was even more focused and did not seem to wander. Overhead of my listening position is a soffit containing my AC return can't move that..So I put a 52 degree angle on it and blended the drywall into the ceiling so to smooth the transition..Sounds better looks really cool. Intalled a pull down Stewart screen 9 foot in front of me. Encased the screen with angles 52 degrees front and sides 40 degrees on the back..Screen rolls up into this ceiling mounted spaceship. Again measured improvements as well as enhancements to audible staging and focus. Lastly I made a hinged false door to hang on the right side of the room that can be stopped at the same angle of the real door on the left side of the room.This new fake door is painted and trimmed to match the wall on which it is mounted.When not in use this fake door lays nearly flat against the wall and is seldom noticed.Again improvements in dynamics focus and stage. In clients room's built from the floor up, angles are at all intersections of wall and ceiling..When allowed or possible corners are no longer 90's. I will soon do these mods to my room..No more stuffing is needed never sounded right with this stuff anyway..More dynamic scale now, live in the sense of weight and impact ...not bright or edgy..Use to feel the need for Sonex and tube traps, not any more..Tom

Tom, what you are saying is very interesting, however if you could expand on this a little, I would appreciate it. I think you understood what I am trying to accomplish and it would be great to hear your thoughts on how this is done. thanks in advance...

" Geometric redirection of SPL is the answer and is possible in most rooms,so has been my experience"

Any details Tom?

Dave

So you buy a preamp with unlimited dynamic scale and match it with a power amp with huge dynamic swing powering a speaker combo that can maximize the flow within your room..All that is great! So then you buy and install products that reduce the scale and dynamic range and really suck the life right out of your hi-fi. The net gain is WHAT? Contradiction here is the reduction of dynamic contrasts.The opposite of what I think most of us are trying to achieve and maintain.Audphile-1 in his post asked if the the redirecting of bass frequiencies was possible or preferable to the absorption of the same frequencys.My experience tells me that the redirection,re-focusing and preservation of sound pressure is much more realistic and fullfilling than sucking the life out of a room, resolving darkness and breathlessness. We have allowed ourselves to be explained into a product category that is mostly a mis applied band-aid attached to a most common occurence.Preservation of the dynamic musical experience should be number one. Geometric redirection of SPL is the answer and is possible in most rooms,so has been my experience.Tom

Dave, that's great. Exactly what I am looking for. I have echo busters corner traps installed in the corners behind the speakers and they were an improvement comparing to no treatment at all. I would think the seams or the bass traps should take the soundstage to a different level. I will most likely pick up the eighth nerve, give it a try and see what happens....thanks

A lot of people at the Audiocircle forum think highly of Eighth Nerve products and there are threads there regarding these...try a search at that site.

The traps I have been playing around with for the last few days are the John Risch DIY jobs that Davewav1 mentioned
above...I have eleven of these that a guy made and gave to me.

One of the things, other than of course a much higher degree of bass quality that these are providing... is at least the same degree of quality increase in all the other freq's.

I am hearing very deep into recordings and hearing many fine details that I had not known were there.

Dave

Right now I have a chance to buy Eighth Nerve seams. They are a little more affordable than Echo Busters. Just curious what opinion people have about these....

This worked surprisingly well for me. http://www.optp.com/shop.cfm?groupid=Foam%20Roller%20Therapy&catid=Foam%20Rollers
Helped trap the bass, and reduced the effect of the all-too-lively high frequencies. You can cut the semi-circle versions in half and place them in the corners, or on the walls. They are more dense than foam, and could be made to look decorative. They are also cheap enough to be worth trying out. And make sure you keep one for working out the knots in your hips and IT band for all you runners & cyclists out there.

Plants are generally useless but I do agree with you about the RealTraps which are now in my listening room. However, the information at that website should be a guide to what to do even if you have to go elsewhere for esthetic reasons. Another useful source of information is:
http://www.avsforum.com/avs-vb/forumdisplay.php?f=91

Kal

REALTRAPS is actually too industrial looking. I did go to the site and read through it, make a lot of sense, but my listenning room is also a living room. Unfortunately I can not have anything that looks like the realtraps stuff. Anything that integrates with the room furniture would be OK. Have anyone tried eighth nerve seams? Are they any good. Or echo busters bass traps are the way to go? Any other solutions? I tried plants in each corner they made a little difference but nothing dramatic. Please keep suggestions flowing. I appreciate any advise at this point as I am pretty fed up with not being able to bring it to a desired level...

You can John Risch DIY acoustic panel and bass traps.

http://www.geocities.com/jonrisch/a.htm

dave

Bass is usually pressurized in the corners and that's the best place to deal with it. For guidance, read the information at:
http://www.realtraps.com/info.htm

Kal

I've been playing around with bass traps for the last couple of days in my room. I stacked 48" traps in every corner at this point and I have to say that my system has gone to a new level.

They work and they work well...beleave what you have read!

Dave