2. speakers
  3. 1047960419

room treatments? is it the room that's bright?

Hi

Tom from New Orleans, here goes with my novel,
please excuse the length

I've been refining my system with ic and speaker cable upgrades - Cardas,Harm Tech, Acoustic Zen, preamp upgrades - Arc LS 5, tube upgrades - pricey nos Telefunken and Siemans,Dac and transport upgrades - EVS MIllenium II and TEAC VRDS 10 transport and power upgrades - equitech balanced power on my front end.

All have made nice improvements. I've been moving steadily toward good imaging, resolution and natural tonal balance.
I've always tried to move towards more musicality - tonal balance, naturalness, air and warmth.

Unfortunately it may be my room that's my guilty culprit for a slightly bright mid and high end, and I don't have a lot of experience in taming that.

I have a 27 by almost 15 by 8 room, hallways on both ends and my speakers are along the long wall, leather couch opposing in a couple foot notched out area (small closets from other rooms notched in on the ends of the hallways).

The speakers are almost 2 feet away from the walls, set in 9' equilateral triangle with the listening area - imaging is very nice (even with a Proton tv on my cwd lowboy equipment cabinet, back a little from the front of the speakers). Floor is carpet (older), walls drywall with drymount music posters on them, ceiling spackled - no special room treatments

The speakers are Von Schweikert Vortex screens - basically a VR4. they are large floor standing. Their tonal balance is good, acoustic instruments sound nice - I play acoustic guitar. I thought maybe the titanium teeters may be the culprits and I've been considering upgrading to VR4se at $6000 or another neutral speaker, but I'm now think my room may be the biggest culprit and would like to take care of that first. At lower volumes things sound nice tonally, but get a little shrill at higher 'more resolving' volumes. I also have a pair of B&W Matrix 2's to compare, which are nice, but they have more cabinet resonance and don't disappear or image as well in the room.

Imaging is great in the room, I went to great detail in the setup, the speakers disappear nicely (a trait I like) and the image is well beyond and behind the speakers (these speakers are designed for true phase coherence.
But things appear to be a little brighter at mid and high freqencies at mid to higher volumes than I'd like. If I am listening in the room behind this room the tonal balance sounds absolutely wonderful even on sax, horns etc(of course imaging suffers).

Is it the room? Is it too reflective that is causing the slight brightness in the mids and highs?

I did an extensive search here on room treatments and I'd like to hear a few more suggestions. I'm single so I don't have the WAF factor, but I don't want anything too hideous looking in the room.

I'm probably less inclined to do a diy project like at David Risch's site, but would be interested in finding some asthetically pleasing but not too expensive room treatments to tame the high and mid freq. Perhaps absorbtion panels on ceiling first arrivals and back wall arrivals, maybe diffusion behind. The low frequencies seem rather nice, so maybe I don't need to go the corner trap route first, plus I have an old wood victrola in corner. I'd prefer something that would be removeable later for resale purposes.

Any suggestions on manufacturers, particularly those not too pricey, who make high quality products that can slightly tone things down? Anybody work with your dimensions or recommend full room treatments based on them? Any elegent or easy DIY projects?

It's distrubing to think that I've ignored my room all this time, when it's more than likely the biggest factor. Doh!

thanks a lot

Tom

thanks

Tom

Can anyone suggest
128x128audiotomb

Showing 5 responses by rives

rives
953 posts
 
Sorry to enter the discussion so late, but I was travelling last week. I've said this before in other discussions, but you have 2 approaches. One is a trial and error, which is not as bad as it might sound for the basics, the other is to hire a group like ours to do the plans.

In the trial and error method I would look at the first reflection points, both ceiling and walls. If possible try diffusion on the ceiling and absorption on the walls. The second area is to work on speaker placement (including toe in). If you go to our site there is a tutorial on speaker placement in the "listening room" section.
http://www.rivesaudio.com/listroom.html
There are many tips in the listening room section and hopefully it will help considerably if you like the experimentation aspect (it is actually fun if you have the patience for it).

Two tools that are useful for helping you determine the severity of your problem and possible solutions. One is the Radio Shack SPL meter (already mentioned), but either use our Test CD which corrects for the non-linearities of the meter or download the correction values which are found on the instructions. (This can be downloaded from our site as well). The other tool is the CARA 2.1 software. It is an room acoustics simulator and can help determine what some possible solutions for your problem might be (we sell this as well, so I may be a bit biased here, but I do think it is a very good value). You can basically model your room, make changes, and see what the theoretical results of your changes are. It does take some time to use and is not the most intuitive program--but is very very flexible and the best I've seen of it's kind so far.

One caution on hiring groups that sell pre fabricated material, they are in the business of selling material. We only sell designs and have no interest in filling up your room with unnecessary items. In fact, we try to use existing furnishings and standard products where ever possible to keep costs down for our clients. In many cases our design costs are offset by the savings in acoustical treatment.
rives
953 posts
 
The reason you are doing two measurements is to determine if the problem areas are solely at the listening position (sitting in a peak or a null), or if the problem is broader than that--a true frequency "suck out" or boost. Most cases are a combination of the two. The first thing you want to do is get to a position with the least problems. The CARA software will help you do this much faster. Once you are there you want to take another series of measurements and see how close or far off from a flat response you have.
rives
953 posts
 
Looks like something happened to our post. We went into some detail on what to look at and some caveats--but I returned to the thread to find that it's not there. Anyway, you do have a few frequencies giving you trouble such as 160. 40 Hz appears to be a placement issue. Mid range could probably use some diffusion and high frequency appears to be overly damped. I can't say all of this for sure without more information, but it seems most probable. Two things to do from here. One is download the SPL instructions from our site, if you haven't already. It goes into some of the caveats that you may run into from this point forward. The other thing is once you get CARA and model your room compare it to these measurements. If they are close--that is very good and you can then further use CARA to simulate changes in the room and discover what it is likely to do to the frequency response and reverberation times. As you can see, this is not the easiest part of a sound system to tackle. It's not like--well let's listen to CD player A vs CD player B. That's why the room is so often ignored as you pointed out at the beginning of your post. Everything is interconnected and very dependent on each other in the room--but you are going about it in the right way--continue, take your time, and it will pay off.
rives
953 posts
 
I probably wouldn't have recommended those traps, but since you have the traps (and they were free), work on their placement critically. The distance from the corner determines the peak frequency attenuation. Off center will broaden this band symetrical placement in the corner will narrow the band. To complicate matters the distance of the speaker to the trap and the corner also play an important role. There are actually multiple combinations that can be used for a variety of results--too lengthy to go into here. I'll be interested in your results. There is no question you can and will make improvements, but I probably would have pursued a different route if you had to pay full price for the traps.
rives
953 posts
 
The problems with bass traps is they generally absorb broad band, and are usually not efficient enough to do the job. Yes, they claim efficiency of 90%, but that's for a very small area relative to the walls that are creating the problem. The result is usally a change of about 5%, which almost not detectable. The tips I gave you on placement will help considerably, but it's still kind of inefficient. There are other designs that we do, and a few companies make some pre-fabricated designs that are similar that are capacitive type. They are more efficient and actually counter balance the frequency that has the problem. They are also much narrower in bandwidth, which means they hopefully won't degrade frequencies that do not need correction. Now that being said, you have a set of bass traps to use, do it! It's not costing you anything yet--except time (which can be expensive--but fun too). You may be able to get them to work for you in your situation and if you can, then that's what makes sense to do. If you can't get them to work and find the limitations I've mentioned a problem, then you might consider one of the alternatives.

I'm glad you got the CARA fast. We try to get all orders out that day or at the latest the following business day. We use USPS for all software orders and quite frankly have been consistently impressed with how fast it's delivered.
More to discover