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Acoustic treatment for windows and a piano

Hello all,

This is my first question after much lurking and a few thread replies. I appreciate everyone who contributes to this community - I’ve learned a lot from you. 

My listening room is 13.5’ wide and 16’ long. On the left side wall I have an upright piano (hard surfaces, reflective), with some acoustic tiles above the piano to dampen reflection. I have a big rug covering most of the hardwood floor, with a thick pad under it. The ceiling is typical bare drywall.  

On the right side wall I have two large glass windows, two separate window cases. I have typical wood Venetian blinds on each window section. 

My problem: Despite a lot of tweaking and positioning, my highs have amazing clarity but are still a bit harsh and fatiguing. I’m thinking I need to treat the windows, it’s likely I’m getting a lot of reflection off them and the hard wood blinds - but maybe the piano is a problem, too, or maybe I’ve reached the limits of my gear. 

Key system points: Rega RP8 TT with Hana SL; Tavish Vintage tube phono pre; Rega Elex-R integrated; Martin Logan Motion 40i speakers. I have good quality interconnects and speaker cable, and I have some sort of vibration control on every component. 

My questions:

1. Is the piano likely part of the problem? If so can I do anything with it? It’s a very nice piano that I play daily so it’s not going anywhere, and I really can’t rearrange the room due to layout. 

2. Are the windows likely part of the problem? If so, would you recommend drapes, acoustic blinds, or something else?

3. As I’ve improved my system, I’ve begun to suspect the amp is maxed out for sound quality. It feels like the speakers could give me a bit more with a better amp. Is it possible the harsh highs are from the amp alone? I’ve read the Elex-R amps can be lean in the highs, and that’s exactly what I’m experiencing. 

Thank you for any thoughts! 
phasemonger
12 responses Add your response
millercarbon's avatar
millercarbon
12,531 posts
 
Like the way you saved the best for last. Keeps the readers interest to not get the answer until the very end. Imagine if I were to tell you right up front Townshend Pods will sweeten those highs? No suspense! Put them under the amp. They will help, for sure, and maybe save the amp. But if not then you simply move them to under the next better sweeter amp you buy to replace the elexr.
rego
378 posts
 
Hello phasemonger, as you have identified the range (highs) you are in good shape for continuing to a solution.
One - the piano is helping with diffusion but could be a source for reinforcement of a resonance.
Try covering at least part of the piano with absorption on the least damped portion (top ... ???).
Two - the glass will resonate and flex dependent on area (other specific characteristics) over some range.
Glass has a different absorption coefficient than drywall.
My guess would be that the glass is not problematic especially with the blinds.
Envious of the piano here !
Try adding some absorption behind the blinds as an experiment (a towel).
Three - being unfamiliar with the list of gear this may be an area to look into.
The good news is that high frequency modes are easy to treat with absorption or diffusion.
A single four inch thick panel would go a long way toward nailing down problem highs.
A hybrid panel would work well.
Be aware that treatment in one range can effect the room ballance.
As for a balance a live end / dead end approach should be a snap.
Work axially side to side high to low (room height / placement).
Good luck ...
dekay's avatar
dekay
5,346 posts
 
Try laying a soft weighted pad on the keys of the piano.

Perhaps a folded blanket with some smaller books/paperbacks on top - as an experiment.

Doing so will slightly damp the workings of the piano (without the hassle of placing something inside).

DeKay
bdp24's avatar
bdp24
9,400 posts
 
As @dekay suggested, damping the piano strings (two per keyboard note---that's a lotta strings!) is the first order of business. They ring like crazy when provoked, much more than an acoustic guitar or drumset. A folded furniture moving blanket will work great.

Second should be replacing the Venetian blinds with either diffusion or absorption. Ideally, you want the left and right walls to be as alike as possible, so whatever you do to one side, do to the other. "Sweeten" the highs with Townshend Pods? Before acoustically treating the room?!
phasemonger OP
23 posts
 
Thanks for the great input! I didn’t even consider the idea of the strings ringing sympathetically… that makes a lot of sense. And I know the two sides of the room are acoustically very different, so that could be part of the issue, too. 
I have the amp on BDR cones thanks to MC, which did wonders for the sound (really!), so I think I’ll work on the piano and room a little then revisit the amp. 
erik_squires
15,630 posts
 
One thing to keep in mind is that you can often compensate for deficits in one side of the room by adding more to the other.

Of course, it's hard to get a good stereo image when your left and right are not balanced but if one side is too reflective and can't be fixed, such as with big bay windows you don't want to hide you can treat the opposite room with extra thick absorbers and diffusion.

And don't ever forget the ceiling.
secretguy
1,570 posts
 
Strings are already damped.
edcyn
1,876 posts
 
You guys made me go check out my my piano, a 19th Century Mason-Hamlin upright. Anyway, the strings for the piano’s top eighteen keys are entirely undamped, and could conceivably resonate sympathetically. The strings for those keys, however, are under extreme tension. They did not respond one iota to my repeated shouts into the piano’s interior. In other words, I don’t think that, because it’s a musical instrument, the piano might be bolluxing up the stereo’s imaging. I do have to say, though, that any piano is a substantial piece of furniture, with a wealth of hard flat surfaces.
phasemonger OP
23 posts
 
Thanks edcyn, I’ll check to see if I have any undamped strings, and yell at them!
dekay's avatar
dekay
5,346 posts
 
I suspect that placing a weight on the damping pedal (if your's has one) might not be a good idea in the long run, thus the simple damping method I mentioned.

Long story (not bothering to tell it) is that hollow stringed instruments (especially pianos) have an effect on room acoustics.

Discovered this when making live recordings in large domestic rooms/basements (basic mono tape recorders, but really good microphones) in the mid 60's.

We had a Baldwin Acrosonic upright that was a very nice sounding piano (would even be so now if properly refurbished).

DeKay
audioman58's avatar
audioman58
3,828 posts
 
I prefer still points under my equipment a bit pricy but the smaller ultra can be had just over $400, also your first reflections very important, on line you can  get 2x4 ft panels with acoustic egg crate foam inside with different color fabrics or scenes .I made A little base where the panel sits in perfect  like book ends in a way, you just put outside a foot or two  from where you speakers are in front to the side  ,it works great on reflections off the wall or whatever . When not using the piano ,either have made or buy a 
slip cover ,this too will avoid all reflective surfaces. My friend have a Big Baldwin grand piano and has a nice slip cover with elastic sewn into the edges it tucks down around and  under the frame.
4krowme's avatar
4krowme
542 posts
 
  My father used to tune pianos on weekends, and he showed me a little about them. First depending on the note, the deepest notes of a piano are one big string tightly wrapped around another large string. As you go up the scale, it becomes just one string being struck, then higher up 2 strings, and finally at the top 3 strings are being struck in order to produce the volume needed. 

 My thinking would be to press the 'soft pedal' down and keep it there, with a weight, giving the most damping of all the strings. Make sure that the top is down, and find a mattress sized sheet of memory foam to cover the piano with. 

 As for glass panes, I have used a quilt on a rack to hold it upright and put it in front of the window. Done. Same can be done behind the system. Incredible difference that you may or may not like. Adjust accordingly.
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