"Book shelf" speakers put on speaker stands = less bass??

[March Audio]

7 minutes ago, opus101 said:

Yep. So?

 

(of a question) asked in order to produce an effect or to make a statement rather than to elicit information.

 

So why did you respond to a clearly rhetorical statement that obviously didn't require a response?  Simple, it was one of your typical jibes rather than anything useful or relevant to the subject.

 

So on topic, do you think franks assertions are correct?  That more secure speaker mounting will stop boom?

[opus101]

3 minutes ago, March Audio said:

So why did you respond?  Simple it was one of your typical jibes rather than anything useful or relevant to the subject.

 

You're welcome to your own hypothesis. I replied because it was interesting to speculate on, as I've already said.

 

I don't have a formed opinion on your secondary question, it would depend a lot on particular details.

[March Audio]

12 minutes ago, opus101 said:

 

You're welcome to your own hypothesis. I replied because it was interesting to speculate on, as I've already said.

 

I don't have a formed opinion on your secondary question, it would depend a lot on particular details.

Well I was obviously right about you having nothing relevant or useful to contribute to the discussion.   Your speculation was wrong.

 

Can we get back on topic now?

[opus101]

2 minutes ago, March Audio said:

Well I was obviously right about you having nothing relevant to contribute to the discussion.   

 

How was your rhetorical question deemed relevant?

[March Audio]

11 minutes ago, opus101 said:

 

How was your rhetorical question deemed relevant?

It was clearly expressing frustration at franks behaviour of bombing every thread he can with misinformed commentary about his elusive and impenetrable "methods".

 

Might be barely acceptable in a subjective thread but certainly not in an objective thread where the basis is factual/science led.

 

This was all plainly obvious.  So as you admit you have nothing useful or relevant to contribute to the actual subject under discussion, can you allow the rest of us to get back to discussing it?

[opus101]

Just now, March Audio said:

It was clearly expressing frustration at franks behaviour of bombing every thread he can with misinformed commentary about his elusive and impenetrable "methods".

 

Might be barely acceptable in a subjective thread but certainly not in an objective thread.

 

I concur with this - mention of, or even allusion to personal frustration is about as far off-topic as can be in a thread in the 'objective' zone.

[March Audio]

16 minutes ago, opus101 said:

 

I concur with this - mention of, or even allusion to personal frustration is about as far off-topic as can be in a thread in the 'objective' zone.

Eh?

 

No it's quite reasonable to make a point that what someone is doing is not relevant, correct, reasonable etc. 

 

BTW it's not just my opinion or personal frustration, just take a look at others similar comments in other threads.

 

As I am going to do right now.  I will ask you, for another time, to stop unless you have something actually relevant to say.  I'm putting you back on ignore so have the last word if you wish, its obvious you are only playing games.

[opus101]

16 minutes ago, March Audio said:

No it's quite reasonable to make a point that what someone is doing is not relevant, correct, reasonable etc.

 

Yep, but that's missing the point. You shared your personal frustration - that's the point.

 

<later edit> Its also quite irrelevant to this discussion whether others have shared their opinion or frustration with/of Frank in other threads. Classic 'whataboutery'.

[March Audio]

Back on topic,  Frank, can you explain why you think an audible boom is connected to the security of the speaker mount?

 

How have you tested your theory?

[fas42]

2 hours ago, March Audio said:

Back on topic,  Frank, can you explain why you think an audible boom is connected to the security of the speaker mount?

 

How have you tested your theory?

 

You are a difficult chap to interact with, you know 🙂 - this was all sorted out over 35 years ago; spikes were the rage back then, and I experimented with those - definitely improved the sound. Thinking through what they were accomplishing, which was to far more strongly couple the cabinet to the underlying support, it made sense to increase the weight to improve that coupling - which made things better, almost without end. Visiting demo rooms, with enormous speakers set up, which had very nondescript bass, and lack of clarity - and then testing how solidly they were mating to the floor, and finding they were ready to bounce from side to side, with the slightest push - helped to confirm the behaviour.

 

Audio friend and I went through an exercise where we stabilised his tiny Tannoys - using a very different approach ... ahh, proper bass!! How nice you decided to pay us a visit ...

 

Nothing stopping you trying the same things - except your belief that it can't be true; therefore you won't try it ... 😉

[4est]

On 11/8/2020 at 9:37 PM, bluesman said:

This is a classic example of bass reinforcement by proximity to reflective surfaces (boundary effect). Floor placement alone boosts omnidirectional frequencies (below 80 or so) by about 3 db. Put it on the floor and against a wall to add another 3 or so. Corner placement on a floor adds another dose.  Reflected bass is close to but not perfectly phase aligned, and this is affected by exact positioning (angulation in all planes, spacing between surfaces and speakers etc).  So the reinforcement makes it louder but often muddies it up.  Read about it in this piece from TAS on improving your bass. Here’s the most relevant paragraph:

 

”Bass from the loudspeaker, radiating omnidirectionally, is reflected from the room’s rear wall and sidewalls. This reflected energy combines with the direct wave from the woofer essentially in-phase, combining constructively to increase the bass amplitude. This is the common phenomenon known as ‘room gain’ - a bass boost added by the room. The direct and reflected waves aren’t precisely phase-aligned, which causes some frequencies to be boosted more than others. In the upper bass, the direct and reflected waves can be out of phase, combining destructively to create a dip in the frequency response. This phenomenon colors the bass, adding an unnatural emphasis or de-emphasis to certain registers of certain instruments, particularly basses. Because the frequency at which this reinforcement or cancellation occurs is dependent on the distance between the speaker and the room boundaries, we can use good loudspeaker placement techniques to mitigate the deleterious effects of this phenomenon.”

This is THE reason. The effects of the boundary reinforcement will swamp out the other differences being discussed here.

[botrytis]

8 hours ago, March Audio said:

Back on topic,  Frank, can you explain why you think an audible boom is connected to the security of the speaker mount?

 

How have you tested your theory?

 

He won't because he has swallowed hook, line, and sinker many of the old urban legend's about speakers and affects.

 

I mean, look at Q Acoustics or Raidho. They both have stand mount speakers, sold with stands, that actually absorb bouncing floors, etc and seem to protect speakers from that.  The Raidho (also Borreson - the original designer) is a desert Island speaker for me as every time I hear them - colour me impressed.

[fas42]

Note, we still have no response as to why real instruments in the home don't require "bass compensation" - but audio systems do ...

 

Ah, the bizarre world of the audiophile - ya gotta chuckle, now and again, 😁.

[Racerxnet]

1 hour ago, fas42 said:

Note, we still have no response as to why real instruments in the home don't require "bass compensation" - but audio systems do ...

 

Ah, the bizarre world of the audiophile - ya gotta chuckle, now and again, 😁.

The room response to the notes being played on the piano are still being effected. Many musicians will attest that the same performance played in a concert hall will sound great, where as the same songs will sound terrible in a gymnasium. Just because you don't hear the room boundary's interference in your home, does not mean they don't exist. Why do you thing concert halls are engineered a specific way??

 

https://www.pianobuyer.com/article/how-to-make-a-piano-room-sound-grand/

 

 Thinking that just because the piano is plopped in the room, and what you hear is accurate is incorrect.

[fas42]

11 minutes ago, Racerxnet said:

The room response to the notes being played on the piano are still being effected. Many musicians will attest that the same performance played in a concert hall will sound great, where as the same songs will sound terrible in a gymnasium. Just because you don't hear the room boundary's interference in your home, does not mean they don't exist. Why do you thing concert halls are engineered a specific way??

 

Yes, there will be a room response - but for the vast majority of rooms the acoustics will be perfectly adequate, for hearing the instruments ... when was the last time someone buying a piano told, that if you don't do a lot to the room to "improve it", that the piano won't sound right?

 

11 minutes ago, Racerxnet said:

https://www.pianobuyer.com/article/how-to-make-a-piano-room-sound-grand/

 

 Thinking that just because the piano is plopped in the room, and what you hear is accurate is incorrect.

 

The piano has to be accurate to sounding like a real piano - because it is! No matter how bizarre you make the acoustics, it's always accurate - by definition. ... It sounds like, 100% correctly, a real piano being played in unusual acoustics ... 🙂

[Racerxnet]

3 minutes ago, fas42 said:

Yes, there will be a room response - but for the vast majority of rooms the acoustics will be perfectly adequate, for hearing the instruments ... when was the last time someone buying a piano told, that if you don't do a lot to the room to "improve it", that the piano won't sound right?

Read the link. Adequate for you, but not so for a musician who wants the best. The piano sounds accurate in a room because it "is" the reference. The replay from your disk has no reference to you. You were never there during the mix. It's only a piano sound to us because it sounds like one. 

[Racerxnet]

If there was a room node at B1 with the piano playing that note in your room, what do you think might happen Frank??

 

 

[fas42]

52 minutes ago, Racerxnet said:

Read the link. Adequate for you, but not so for a musician who wants the best. The piano sounds accurate in a room because it "is" the reference. The replay from your disk has no reference to you. You were never there during the mix. It's only a piano sound to us because it sounds like one. 

 

Why is what the musician thinks of it relevant? What matters to me is that I experience the illusion of a piano playing in front of me - if it fails to deliver that, then the fact that there is a resonance in the room for some note has close to zero relevance for that failure ...

[Confused]

On 5/22/2021 at 8:12 AM, fas42 said:

 

Of course there are room modes - but our hearing adapts to them ... a real grand piano being played by a real person in a real, relatively small room, doesn't sound boomy - when the bass notes are being forcibly played ... at least, I have never heard such an instrument irritate me with 'resonances'.

 

So, a simple question: why is a piano OK - but a recording playback setup needs all this, umm, fiddling?

As others have pointed out, a piano will sound different in different rooms, and indeed will sound different depending on where you stand in a room.  There are many different techniques for recording pianos, and it is well established that different locations for microphones etc. will yield very different results in that recording.

 

As for real instruments exciting room modes, I mentioned the effects of the room on an unamplified bass drum in an earlier post.  In addition, I also recall one occasion where a bass guitar hit a room resonance mode with spectacular effect, and I mean truly spectacular, it is like it increased in volume about six or ten times.  Of course, this does not really count as an example of a "real" instrument, because it was an electric bass and it was the stage amp hitting the mode, which is not really different to a hifi system doing it.

 

I think it will be much harder for a piano to hit a room resonance mode than a hifi system reproducing the piano.  When you have a hifi in a room with a known resonance mode, you can usually find some dimensional evidence as to why.  Lets say you have a resonance at 50Hz and a null at 100Hz.  This equates to wavelengths of about 6900mm and 3400mm respectively .  You will probably find some aspects of the setup have relationships to these wavelengths.  So you might have your speakers 850mm from the rear and side walls, as it happens this is exactly one quarter of your null frequency wavelength, so your speaker location exacerbates the natural effects of the room null.  The same thing works with the peaks, so you might find that the back wall is 3450mm (half 50Hz wavelength) or maybe 6900mm (full 50Hz wavelength) from the speakers.  Then similar relationships with the speaker distance from the ceiling, the distance between speakers, other walls and so on.

 

So you have these very complicated interactions between all the room dimensions, which in themselves will naturally lead to resonances, peaks and nulls at different frequencies, and the specific location of the speakers.  It is here that a piano in a room is very different to a stereo system in a room.  With a stereo you quite probably do have your speakers placed identically distanced from the floor, ceiling and back wall, possibly to millimeter perfection., and these speakers are producing the sound almost as two single points in space, which exacerbates these effects in a way that a piano will not.  Consider that a piano is big, and the sound does not come from one point in space, not even close to this.  The sound is created by vibrations of a very long string, the soundboard, and the entire body of the piano acts as a resonator, together with the lid.  This is a huge dispersed area which is working together generating the sound, not the entire sound from one point.

 

There is perhaps a parallel to this with audio.  One technique for getting very even bass in a given room is to use a large number of subwoofers, or a "subwoofer swarm" as some might call it.  The idea here is not to have lots of subs to get lots of bass, but rather to have the subs located asymmetrically to the room and to each other, so each one will have different interactions and create different peaks and nulls, which will then tend to cancel out, and can be then be brought to a very even bass response, probably with room correction to prevent the overall level of bass being excessive, but at least there will be limited nulls, which are otherwise difficult to "fill" or correct.

 

This is why a piano is less likely to hit a pure room resonance than a stereo speaker, it is effectively generating the same effect as a subwoofer swarm.

 

 

[Racerxnet]

5 hours ago, Confused said:

This is why a piano is less likely to hit a pure room resonance than a stereo speaker, it is effectively generating the same effect as a subwoofer swarm.

I was looking for a dispersion pattern of the piano vs a speaker to help illustrate the interaction. 

[fas42]

13 hours ago, Confused said:

So you have these very complicated interactions between all the room dimensions, which in themselves will naturally lead to resonances, peaks and nulls at different frequencies, and the specific location of the speakers.  It is here that a piano in a room is very different to a stereo system in a room.  With a stereo you quite probably do have your speakers placed identically distanced from the floor, ceiling and back wall, possibly to millimeter perfection., and these speakers are producing the sound almost as two single points in space, which exacerbates these effects in a way that a piano will not.  Consider that a piano is big, and the sound does not come from one point in space, not even close to this.  The sound is created by vibrations of a very long string, the soundboard, and the entire body of the piano acts as a resonator, together with the lid.  This is a huge dispersed area which is working together generating the sound, not the entire sound from one point.

 

This is the most plausible explanation, looking at the situation conventionally.

 

13 hours ago, Confused said:

 

There is perhaps a parallel to this with audio.  One technique for getting very even bass in a given room is to use a large number of subwoofers, or a "subwoofer swarm" as some might call it.  The idea here is not to have lots of subs to get lots of bass, but rather to have the subs located asymmetrically to the room and to each other, so each one will have different interactions and create different peaks and nulls, which will then tend to cancel out, and can be then be brought to a very even bass response, probably with room correction to prevent the overall level of bass being excessive, but at least there will be limited nulls, which are otherwise difficult to "fill" or correct.

 

This is why a piano is less likely to hit a pure room resonance than a stereo speaker, it is effectively generating the same effect as a subwoofer swarm.

 

 

 

If the large body of the instrument is part of the answer, why not make the subwoofer large in effective area too - the Bose 901 concept - lots of small drivers spread over a large surface area? I certainly know it doesn't work in the purely vertical mode - the Steinway Lyngdorf  Model D system I heard once was the most awful rig I had listened to in a long, long time - massive, booming bass, that was quite absurd, of a recording of a piano!

[Confused]

17 hours ago, Racerxnet said:

I was looking for a dispersion pattern of the piano vs a speaker to help illustrate the interaction. 

I presume you could not find anything?

 

The link below might be interesting.  It is not exactly what you were looking for, but it does serve to illustrate that a piano does not behave like a speaker.

 

Modeling and simulation of a grand piano. (inria.fr)

 

[Confused]

8 hours ago, fas42 said:

 

This is the most plausible explanation, looking at the situation conventionally.

 

 

If the large body of the instrument is part of the answer, why not make the subwoofer large in effective area too - the Bose 901 concept - lots of small drivers spread over a large surface area? I certainly know it doesn't work in the purely vertical mode - the Steinway Lyngdorf  Model D system I heard once was the most awful rig I had listened to in a long, long time - massive, booming bass, that was quite absurd, of a recording of a piano!

The key thing is asymmetry.  This is why the subwoofer swarm technique works.  With the Bose 901 the drivers are more or less the same distance from the front wall, back wall, and the variance in distance to the side wall is small enough to be more or less insignificant.  The Bose is also considerably smaller than a piano.  The Steinway Lyngdorf  Model D system will have identical distances to many room surfaces also.  The Steinway Lyngdorf  Model D system you listened to may well have been suffering from an unfortunate interaction with the room, maybe room treatment or correction via DSP would have improved things.

 

With multiple subwoofers, or even one subwoofer, the ideal location(s) will most likely be some distance removed from the main speakers.

[fas42]

No reason for a subwoofer with many smaller drivers to be symmetrical in that fashion - firing downward, they can be spaced over a large area; say, perfectly mimicking a grand piano lid! 😛. And of course, there are instruments that produce bass notes that are largely vertical; the double bass, say.

 

That Model D was a complete mess - the treble was truly awful - so I suspect the rig had major issues all round - to be assured that it wasn't the recording, I had it played on the Gryphon plus Wilson setup on the other side of the room ... ah, much, much closer to sounding reasonable ...