Odd tweak?

[YashN]

Since a couple of weeks, I noticed the sound has greatly improved: better dynamics and separation, enhanced presence.

 

It was head-scratching as I had changed nothing at all seemingly in the system: the sockets on the dedicated lines had settled by now and the vacuum tubes on my superlative DIY Single-Ended Triode were already warm and settled too.

 

Then it dawned upon me that the only thing which changed in the room was the following:

 

we added a new TV screen about 3/4 of the distance from the listerning position to the plane containing the speakers. It's a rather large screen, so that sitting in front of it (rather close), the edges obscures half of our speaker stands. The top edge is approximately 11 cm below the speaker cabinet bottoms.

 

So I was thinking why this could make the difference in sound. It looks by the arrangement that the waves from the drivers going downwards towards the listener are instead now screened and absorbed and reflected by the back of the TV.

 

The reflections then go mostly back towards the back wall attenuated I guess, some go through the vents in the TV's back and get attenuated inside.

 

Could it be that what I am hearing is less reflections on the floor, and less distortion between the two drivers?

 

This was quite odd and I wouldn't have thought of inserting a panel at that distance and of that size to increase SQ.

 

Of course, you need not try it with a TV, any large panel could do for a test.

 

I wonder what would happen if I installed a proper acoustic panel in place of the TV or a diffuser with the cubes facing back at this location...

[Blake]

Yes, head scratching for sure.

 

How placing a large tv screen in front of the speaker plane could improve the sound as you describe (better dynamics, separation and enhanced presence) completely defies all logic/physics. Ideally you don't want anything between the speakers, let alone in front of them.

[sphinxsix]

 

I wonder what would happen if I installed a proper acoustic panel in place of the TV or a diffuser with the cubes facing back at this location...

The room acoustics treatment is usually a good thing but the place where the TV is placed isn't the first choice spot for an acoustic panel or anything. The first question that comes to my mind is - is there a carpet on the floor in the space between the speakers and your listening hot spot.? If not - this is the first thing to be done. The next one - taking care of first sound reflections from the walls.

[YashN]

Yes, head scratching for sure.

 

Ideally you don't want anything between the speakers, let alone in front of them.

 

That's what I thought too. Turns out right now, the sound is better.

 

Have you tried?

[Blake]

That's what I thought too. Turns out right now, the sound is better.

 

Have you tried?

 

Putting a large tv screen in front of my speaker plane? No. I don't have a tv in my listening room.

[YashN]

The first question that comes to my mind is - is there a carpet on the floor in the space between the speakers and your listening hot spot.? If not - this is the first thing to be done. The next one - taking care of first sound reflections from the walls.

 

Yes, there used to be a carpet in between the speakers and the listening position, actually a couple of them. Recently though, we've thrown these away to get new ones, so currently, the floor is bare which I do not prefer but until the new ones come in, floor reflection effects must be taken into account.

 

Good point about the first sound reflection on the wall too: I normally have one of my acoustic DIY panels behind our seating position on the wall for first reflection absorption. This too is temporarily removed: I need to fix the back of it as a small tear has exposed the fibre glass within so I stored it away in a safe place for now.

[YashN]

Putting a large tv screen in front of my speaker plane? No. I don't have a tv in my listening room.

 

Fine.

 

I gather you have no interest in trying either?

 

Bear in mind the laws of physics have been rewritten time and time again in the past, so your comment about that have no amount of semantic importance.

[Blake]

Fine.

 

I gather you have no interest in trying either?

 

Bear in mind the laws of physics have been rewritten time and time again in the past, so your comment about that have no amount of semantic importance.

 

 

Nope, I won't be trying this.

 

 

I'm not sure the rest of your comments to me a necessary or warranted.

[YashN]

Nope, I won't be trying this.

 

Cool, then feel free to leave this thread because it isn't for you.

 

I'm not sure the rest of your comments to me a necessary or warranted.

 

Applies to yours in the first place, doesn't it?

 

Besides, I don't care what you do or not do with your TV because if you had read more carefully, it doesn't need to be a TV to test this.

[blownsi]

If changing the reflective sound improves what's going to your ears, I would question whether your speakers are angled correctly. Had you experimented with toe-in to get the best sound before inserting the tv?

[sphinxsix]

Ok... So you have no any acoustic absorbing panels neither on the wall behind you nor on the side walls first reflections. Additionally you have removed the carpet that used to be placed between the speakers and your listening spot, you have placed a TV in it's place which blocks some very strong sound floor reflection (that always ruins the sound, so it's good it is minimized) and you are very suprised the sound in the room got better and you recommend the procedure to everybody.. Just kidding of course

Let's get serious.. You've inspired me deeply. Today I removed the carpet, the bookshelves, the furniture and everything from my listening room. TV too. The sound got terrible! I went to the fish market and bought a fish. A huge 2m long marlin (spearfish). Quite cheap. I placed the marlin between the speakers and me. The sound improved beyond belief! The midrange opened and became much more detailed, the same thing happened with high frequencies which in addition got much smoother. The bass control improved dramatically! You'd have to hear the soundstage to believe a change like this is possible! But.. I didn't stop here. I poured 10 bottles of hot mexican ketchup onto the marlin. This didn't bring as dramatic changes as the marlin but the sound still got better! It's Heinz by the way.

I was listening to one album after another like in trance. So enjoyable my system's sound has become. And then a minor problem appeared - I smelled a strange unpleasant smell. Someone's got an idea how to get rid of it and not to ruin the sound I worked so hard to achieve.?

Ps. Anyway I'm thinking about acoustic panels business. 'Merlin Acoustics'.. How do you like the name guys.?

[christopher3393]

Ok... So you have no any acoustic absorbing panels neither on the wall behind you nor on the side walls first reflections. Additionally you have removed the carpet that used to be placed between the speakers and your listening spot, you have placed a TV in it's place which blocks some very strong sound floor reflection (that always ruins the sound, so it's good it is minimized) and you are very suprised the sound in the room got better and you recommend the procedure to everybody.. Just kidding of course

Let's get serious.. You've inspired me deeply. Today I removed the carpet, the bookshelves, the furniture and everything from my listening room. TV too. The sound got terrible! I went to the fish market and bought a fish. A huge 2m long marlin (spearfish). Quite cheap. I placed the marlin between the speakers and me. The sound improved beyond belief! The midrange opened and became much more detailed, the same thing happened with high frequencies which in addition got much smoother. The bass control improved dramatically! You'd have to hear the soundstage to believe a change like this is possible! But.. I didn't stop here. I poured 10 bottles of hot mexican ketchup onto the marlin. This didn't bring as dramatic changes as the marlin but the sound still got better! It's Heinz by the way.

I was listening to one album after another like in trance. So enjoyable my system's sound has become. And then a minor problem appeared - I smelled a strange unpleasant smell. Someone's got an idea how to get rid of it and not to ruin the sound I worked so hard to achieve.?

Ps. Anyway I'm thinking about acoustic panels business. 'Merlin Acoustics'.. How do you like the name guys.?

 

I must apologize. I am in Ouisconsing and Marlin $$$. So I use locally sourced item. It is cow. Bigger than TV, I think maybe (cow just loaner). Sound? My system sound same, YMMV, no speakers, so maybe not valid. Cow? Bad Idea. Hungry. And make cowpie! Best suggestion? Take room reflections out of play. Otherwise, check hearing for seasonal allergies. And don't forget mood swings! Different times of day I hear same music differently.

 

Yashn, you are very knowledgeable audiophile, but maybe approach communicating this problem more tentatively? You maybe found something but be nice to Blake, who raises reasonable issue, and also knowledgeable.

[sphinxsix]

I use locally sourced item. It is cow

I like the idea of cow. But (I don't know why) I'm more attracted to underwater world. Will think about whale sharks acoustic panels for bigger rooms.

[mansr]

I like the idea of cow. But (I don't know why) I'm more attracted to underwater world. Will think about whale sharks acoustic panels for bigger rooms.

Perhaps an octopus along with some seaweed drapes to form a garden of sorts.

[sphinxsix]

Perhaps an octopus along with some seaweed drapes to form a garden of sorts.

 

 

I love the idea! How about a couple of nice pieces of coral reef in the corners.?

And putting on diver's uniform before listening sessions.?

[sphinxsix]

Ps. I am sorry for the sarcastic tone of my posts here but let's be a little bit more serious or we will all finish in an audio lunatic asylum

[YashN]

Humour is fine by me.

 

But what I reported is serious too.

 

I think it makes sense following sphinsix's observations that the placement of the TV is affecting what happens with the floor reflection and possibly the back wall reflection.

 

Now, I can easily put back another back wall panel as I do have a spare one (it is being used right now to block light from a window when we want to watch movies in a more immersive way).

 

Here is some additional information: underneath the TV, in the middle, is a space of about 30cm. In that space I have put one centre channel speaker (my old Fostex PM0.4 monitor) and on its sides, some blu-rays, so that portion isn't totally free to reflect sound. This is temporary as we were surprised by this TV not having a centre foot, but rather two edge feet so it's resting on two separate blocks.

 

Now, above the TV, the lines from the drivers to my ears' level are unobstructed.

 

Since the TV isn't blocking a lot of the waves going to my back, I think the effect I am hearing has more to do with that floor reflection rather than the first ones behind the listener.

 

For our setup though, testing by doing combinations of removing the TV and carpet on the floor isn't going to be possible for now: I'd need to have a separate setup... not sure when that will happen.

[YashN]

Yashn, you are very knowledgeable audiophile, but maybe approach communicating this problem more tentatively? You maybe found something but be nice to Blake, who raises reasonable issue, and also knowledgeable.

 

Blake was dismissive outright, and on top of that has no desire to do any testing. We don't need that kind of thing.

[YashN]

If changing the reflective sound improves what's going to your ears, I would question whether your speakers are angled correctly. Had you experimented with toe-in to get the best sound before inserting the tv?

 

I experimented a little with toe-in when we got the speakers: they are Totem Mites and by the manufacturer's own instructions, they don't need to be toed in as much as other brands. The current toe-in is slight: if you compared to other brands, you would probably like the other speakers to be more toed in than our setup.

 

I can vary the toe-in rather easily if need be. Moving the TV on the other hand is less of an option for now.

 

The question of toe-in is overall interesting: with this observation in my setup with the TV added, I was thinking of Ken Ishiwata's habit of doing extreme toe-in. This probably helps with some of the reflections, especially back ones (from the speaker perspective) and secondary reflections too (these would also go at the back from the speaker perspective IMO).

[sphinxsix]

@ ' I think the effect I am hearing has more to do with that floor reflection rather than the first ones behind the listener.' Seems true to me.

Toeing in has mainly to do with directional characteristic of the speakers - you may avoid excess high freqencies by not toeing them in but also with minimizing side walls reflections by toeing them in strongly - the soundstage can in that case became slightly narrower but more precise. It is even possible to toe the speakers in so that the speakers 'axises' lines cross in front of the listener! In some situations this makes sense.