New system has fatiguing, harsh high frequency sounds. How to fix?


I just purchased my first audio and home theater system (other than a bluetooth speaker or computer speaker system). I use it for listening to music as well as watching movies. It is a tremendous upgrade and I’m enjoying it. It has clarity and detail that I have never heard before. However, I notice a harshness in the high frequency sounds when listening to music.

I would like my treble to be smooth, sweet, soft, silky and gentle. Right now it is the opposite of that. It is annoying, screechy, metallic and harsh.

I am seeking a solution to that issue. From the little I have been able to find on this subject, it seems that room acoustics might be a big part of my solution. Is that true? If not, what is my next step? An equalizer? I can’t see many options for big changes in speaker placement. At most I can move them a few inches or change the angles.

My listening room is about 11.5 feet by 11.5 feet and square except for the doorway in the back corner which protrudes into the room 18 inches x 44 inches. In the room are a bookcase, couch, end table, media center stand (holding TV, center speaker, receiver, disc player and Roku), computer & computer monitor, my speakers (and rear speaker stands), a ceiling fan and that’s about it... I’m describing the room on the assumption that the room (or its contents) are relevant to the treble problem I’m describing. (However, throwing some thick blankets over my TV and computer monitor, as a test, did not change the issue.)

Here are my home theater components:

  • Computer monitor: WASABI MANGO UHD400 40" 3840X2160
  • TV: LG OLED65C7P 65"
  • Receiver: Sony STRDN1080
  • Disc Player: LG UP875 4K BLU-RAY PLAYER BestBuy SKU 5979504
  • Streaming Box: Roku Ultra streaming player (model 4660)
I mention the monitors (and their size) in case they play a role in reflecting sounds.

Speakers:
  • Front 1: Polk Audio RTi A7 floorstanding speakers
  • Front 2: Polk Audio RTi A5 floorstanding speakers
  • Center Speaker: Klipsch RP-250C Center Channel Speaker
  • Subwoofer 1: Polk Audio PSW125 Subwoofer
  • Subwoofer 2: Klipsch R-112SW Subwoofer 
  • Rear/Surround: Polk Audio RTI A3
Speaker Layout: 5.1 layout with two pair of front speakers and two subwoofers.

The front speakers are on either side of the LG TV on the front wall (and near the room corners. The front speakers are angled in. Minimum distance to wall is 10", but measuring straight/parallel from back of speaker to wall is at least 18". From side of speaker to wall is at least a foot (one side of room has 30 inches). There is only 3" between each RTi A5 and RTi A7 speaker.

The rear speakers are behind the couch at each corner and against the back wall.

One subwoofer is in the back corner. The other is midway on the other wall and angled toward listening area.

For music, I usually prefer listening in 2-channel stereo. The dual pairs of front speakers are awesome. (I initially started out with a 7.1 layout but I prefer this layout now.) The high frequency problem exists even in 2-channel stereo. It also exists if I use only 1 pair of front speakers.

Wiring
All speakers are bi-wired, except the center (and subwoofers), which don’t support it. (Not bi-amp’d, just bi-wired*.)

Speaker wire: Mediabridge 12AWG 4-Conductor Speaker Wire (100 Feet, White) - 99.9% Oxygen Free Copper - ETL Listed & CL2 Rated for In-Wall Use

* https://www.qacoustics.co.uk/blog/2016/06/08/bi-wiring-speakers-exploration-benefits/

Banana Plugs:
  • Mediabridge Banana Plugs - Corrosion-Resistant 24K Gold-Plated Connectors - 12 Pair/24 Banana Plugs (Part# SPC-BP2-12 )
  • Sewell Silverback , 24k Gold Dual Screw Lock Speaker Connector
  • Ocelot Banana Plugs, 24k Gold Plated Connectors, Open Screw Type
BTW, my prior speakers were the Edifier e25 Luna Eclipse. I thought they sounded good and I did not remember them having these harsh high frequency sounds. After listening to my new system for a week, I went back to those for a test and they sounded horrible in comparison. The harsh high frequency sounds are much worse, and every other aspect is worse as well. (That shouldn’t be a surprise given the price ranges being compared, but my incorrect memory had been that they didn’t have this issue.)
lowoverdrive
@ kosst_amojan

I agree with all you said in the last post.  Just thought your first post was a bit harsh, could have been a bit diplomatic about it. 

I can understand why a person new to audio might like the idea of two sets of speakers.  Heck, we always say if YOU like and enjoy your system, that's what matters.  But the OP doesn't seem to like the sound, so I agree better speakers would be number one on the to do list.
I have come to think that the problems need to be adressed at the root. Speakers and their interaction with the room are responsible for 90% of  sound quality:
1 it is an illusion to think that it will ever be possoble to have really good sound in that room. It is too small, and because it is square, the room modes will also be bunched together. All that is possible is casual listening with a pair of mini monitors (you could use your old speakers for that, with a cheap Sony STR 130 if you still want some sound in that room).
2 Since speakers are so important, and because they are also by far the most expensive component, you have too many of them and they are not as good as they should. Why not opt for a 2 channel HT system? That is what I did: you give up some surround effects, but you gain a lot of sound quality. Since you seem to be in a position that you can return a lot of your gear (all the Polk stuff, including the Polk Sub (?), the Sony, and perhaps also the LG disc player?), do so. Move over to the mid size room, and use whatever budget you have to buy some really good speakers (Harbeth M30.1?) and some affordable electronics (Harbeths do not need fancy electronics or cables - sell those too if they are worth any money). How much budget would this create? Electronics: for example an Oppo 205 disc player and pre amp (if your LG does not have the right inputs and outputs and volume control), plus a beefy Emotiva or pro audio power amp.
Hi allJust some thoughts: How about introducing a tube-based pre-amp in the set up? And smaller speakers.
I would not have used such large speakers (as in the first pictures) for such a small room.
Recently I was on a demonstration of amplifiers at a local HFi dealer. They used a relatively small listening room, with some large floorstanders. I commented that the sound was hard and "edgy". They switched to smaller stand mounted speakers and the sound became a lot softer and more comfortable to listen to.
I use Spendor SA1 speakers in my living room (together with the Sugden A21SE Amplifier and a vacuum tube based DAC). This gives an incredibly comfortable sound and has no problem filling the entire living room with sound.
Oh – and i always buy second hand stuff, so i get great sound for half the price :-)
I've owned an Onkyo and used Polk speakers and it sounded good with no brightness... but maybe kosst_'s knowledge is better than my ears
And for a cheaper version of my two channel HT suggestion, and more so if you cannot return the LG disc player: a Yamaha AS 801 2x100 watt amplifier with optical, coaxial and usb digital inputs, plus the somewhat cheaper Harbeth C7ES-3 speakers.
Unfortunately unlike the Oppo the LG player cannot quite serve as a pre amplifier because it does not have a digital input (apart from a LAN networking connection and a USB that will only take memory sticks but not computers).