The Advantages of Floor Coupled Up-Firing Speakers

[graaf]

Originally Posted by el`Ol

Not difficult but expensive if it has to have WAF.

what about deflecting? wouldn't it be cheaper, higher WAF and at the same time more effective (absorption is never 100%)?

Originally Posted by el`Ol

Better-suited drivers will be cheaper.

cheaper perhaps but better?

anyway - I want to keep it simple so that anyone can do it
therefore I stick to 8'' Fostex one way
add separate tweeter and woofer and simplicity is lost
also I don't believe that really good two-way could be cheaper

best,
graaf

[graaf]

Originally Posted by graaf

therefore I stick to 8'' Fostex one way

I have chosen the Fostex for one more important reason that is that in the case of a closed box the Fostex needs only small volume to work, and small volume plus careful choice of box proportions means less problems with the waves reflecting and standing inside

also the big magnet of Fostex serves as such as a nice standing wave breaker in a shallow box

another advantage of going omni like in CFS from the "driver-enclosure as a system" perspective is that decoupling the speakers drivers from the enclosure becomes very easy:

Beautiful Swingin' Speaker

best,
graaf

[el`Ol]

I see you are not interested, but if you wanted to do the folded TL thing I suggested for the Visaton B200 you could get that cheaper with the Philips 9710.
eBay Verkäufer: revani67: Audio Hi-Fi
Who is interested can get the TSPs from me.

[graaf]

Originally Posted by el`Ol

There is a video where someone drops an egg on a 3 cm gel cushion from 10 meters height without breaking it. But this is the last thing I would spend my money on

why? what is wrong with that?

[el`Ol]

This would be highend (and it is not meant positively when I use this word). Put lots of money in measures one hardly hears in direct A/B comparison instead of putting more money in the essential things.

[Elias]

Hello,

This is kind of a strange thing.. As I see it, you like to maximize room reflections by using wide radiating monopole box, and at the same time you like to minimize room reflections by finding a placement for that box. The obtainable result is highly room dependent, surprisinlgy But the point is in a given room by this method you can only achieve the goal up to a certain limit.. Is that limit enough?? Does it satisfy you?? What if other method could get better end result??

For me, the most straightforward and efficient method for minimizing early room reflections is to use highly directive source. Not a monopole box! Then the room placement is not so critical!

Originally Posted by graaf

... so much for the advantages of this CFS speaker's placement option, now on to some problems
with stereo basis of ca 280 cm and the listener's distance from both speakers (the path of first wave) of ca 250 cm:
- first reflection from the floor for such short speaker is not reaching the listener at all (just like in the previous example)
- first reflection from the ceiling is delayed by ~9 ms ( (just like in the previous example)
- first reflection from the opposite wall is delayed by ~10 ms
- first reflection from the back wall is delayed by ~14 ms
...
- first reflection from the front wall is delayed only by ~2 ms
- first reflection from the side wall is delayed only by ~4 ms

I think it is up to YOU to decide if those reflections are detrimental or not for you. Afterall this is a diY audio What we are doing here is to do audio for ourselves, right?

Any psychoacoustic study will tell you a set of observed perceptions for a specific feature of human hearing for average population. They will not tell you how YOU perceive it! Also they will not tell you what you should like, or not like. Talking about listening room reflections it is perfectly valid for the end user to like or dislike them. It's up to you to decide.

I find it amusing when some forum members seem to thing everyone are the same and their perceptions are identical. There are not!

Originally Posted by graaf

IF those reflections are indeed detrimental to the sound (which is not certain but let us assume that they are) then something must be done with them

- Elias

[el`Ol]

Originally Posted by Elias

This is kind of a strange thing.. As I see it, you like to maximize room reflections by using wide radiating monopole box, and at the same time you like to minimize room reflections by finding a placement for that box. The obtainable result is highly room dependent, surprisinlgy But the point is in a given room by this method you can only achieve the goal up to a certain limit.. Is that limit enough?? Does it satisfy you?? What if other method could get better end result??

For me, the most straightforward and efficient method for minimizing early room reflections is to use highly directive source. Not a monopole box! Then the room placement is not so critical!

O.K., let's surrender. This reflection thing is too hard for us.

[graaf]

Originally Posted by el`Ol

This would be highend (and it is not meant positively when I use this word). Put lots of money

lots of money for 3 cm Alpha Gel cushion perhaps (I don't know) and I also think it would be an overkill
But what I am thinking of is rather to use some recycled air-infused Sorbothane from "SorboAir" insoles

Originally Posted by el`Ol

in measures one hardly hears in direct A/B comparison instead of putting more money in the essential things.

well, I know that probably the effects of vibrations of speaker enclosure's walls are more or less audible for some and more or less inaudible for others, depending also on circumstances, BUT decoupling of the driver is just nice engineering idea advocated by many competent engineers including members of BBC research staff from it's classic era, Linkwitz, Yoshii-san and many others
It seems that ideally the driver and enclosure should be decoupled, though the idea is not implemented frequently because it is just not that easy to be implemented appropriately in standard front-firing box speakers.

best,
graaf

[graaf]

Originally Posted by Elias

Hello,
As I see it, you like to maximize room reflections by using wide radiating monopole box, and at the same time you like to minimize room reflections by finding a placement for that box.

not really by using such a strange wide radiating monopole box I just want to have constant directivity as cheaply as possible
the truth is that such a quasi-omni is closer to the ideal than any dipole or waveguide, because all reflections on a given lateral plane are spectrally exactly the same period
such a strange box have two more big advantages over conventional front-firing alternatives from the start:
- the first is complete elimination of significant first reflection off the floor, which according to virtually all psychoacoustical studies is detrimental to realism of reproduction
- the second is sufficient delay of ceiling reflection

the only other alternative solution with which such results are achievable is true line source, Beveridge ESL for example, very costly alternative
in fact my strange boxes (I like that name ) were conceived as cheap practical simulation of Beveridge ESL radiation pattern

and then I want to have just many options with regards to audible reflections, a form of "reflections steering" by the use of careful placement and deflectors, becasue some reflections are considered bad but some other are considered quite good

so there is nothing contradictory in my approach

Originally Posted by Elias

the point is in a given room by this method you can only achieve the goal up to a certain limit.. Is that limit enough?? Does it satisfy you?? What if other method could get better end result??

It would be great! but I doubt - as to "better", note that "satisfy" and "better" are two separate issues

and frankly speaking I am perfectly satisfied now with my mono setup and I don't care for stereo imaging/soundstaging at all

what I am doing here is just playing with ideas for the benefit of all who may be concerned, all dissatisfied audiophiles interested in trying something different, especially ordinary music lovers - lacking in woodworking and other technical skills, with room arrangement difficulties and other WAF concerns
therefore I want to keep it as simple and as cheap and as decor-firendly as possible

I am doing this because I am interested in audio, I have some experience with such things and I just like playing with ideas, especially when it is pro publico bono, it's just a matter of déformation professionnelle - I am an academic lecturer

Originally Posted by Elias

For me, the most straightforward and efficient method for minimizing early room reflections is to use highly directive source. Not a monopole box! Then the room placement is not so critical!

"straightforward and efficient" perhaps yes but not the best, it is out of the question

to get the best You either need true line source like Beveridge ESL or strange box plus some systemic thinking about "loudspeakers and room as a system"

Originally Posted by Elias

I think it is up to YOU to decide if those reflections are detrimental or not for you. Afterall this is a diY audio What we are doing here is to do audio for ourselves, right?

right 100%!!
Let there be no misunderstanding - all I am doing here is giving You some more choice, You will not read about things I am writing about in this thread anywhere else on the web

Originally Posted by Elias

I find it amusing when some forum members seem to thing everyone are the same and their perceptions are identical. There are not!

I would say they are as far as everyone discussing here is biologically a specimen of the genus Homo sapiens

best,
graaf

[el`Ol]

Yesterday I tested The Kef iQ70 in a shop. It has about the price I paid for my speakers and the Kef coaxials are said to have the most realistic imaging among the conventional speakers.

My test result is that they deliver the same "information" as my Carlssons in the horizontal plane, but not the "reach out and touch effect" and not the 3-dimensionality. One of my "hate discs" was the same catastrophy there, so probably I was too fast in my conclusion that the Carlssons are incompatible with synth reverb recordings.

Again my request for an up-to-date synth reverb recording with good imaging. Can I write decoded lossless files on CD with a freeware program? If so it would be nice if someone could send me one. If I needn't pay anything it could also be pop.