HIFI Advices please read

Catcher10 wrote: If the sub is designed to move so much air mass, even with my tiny Bose sub I have blown out a candle flame...

Catcher10 wrote: ...I wondered if putting your sub almost directly behind your bookshelf speaker (as in oliverstoned setup), would add unwanted vibration or movement? Is this possible?

oliverstoned wrote: Some audiophiles even put some hydraulic jacks on all sides of their subs... It not only works for me but for everybody: if you don't do that, the low dribbles. The effect is huge. Anyway, it's not the fault of engineers but money and weight contraints. Including a 100lbs plate would have a cost in freight as well. If you want your sub to work fully, you have to add weight or find another way, that's why optimization is necessary.

Edited by Dean - September 19 2011 at 10:07

 okay... yes it will sort of do that... the weight of the rock puts the sidewalls of the cabinet under tension, which only serves to move the resonance higher up the frequency spectrum, it will also create a sub-sonic pendulum type effect (stick with a weight on the end) which may not be such a good idea. But, again - if it works for you then that's fine. Frankly I'm surprised that the sub needed such drastic (and brutal) treatment - those design guys at Magnat should be able to design a cab that doesn't rattle.

oliverstoned wrote: It doesn't sounds stupid on the paper but i recently moved my system to the living room but just before it was in a less than 30m2 room with low ceiling and full of furnitures and it wasn't sounding unpleasant at all...I think each room has its acoustic, some rooms stand the extreme low, others don't.

Obviously there is more to room acoustics than just size and I did mention sound absorbing vs. sound reflecting surfaces (ie the amount of soft and hard furniture in the room). Position is also important, a sub in a corner is going to reflect off 3 room surfaces whereas one placed in the middle of a wall will only reflect off two; and one place behind furniture/equipment rack will be absorbed/reflected differently to one in front that has no obstructions. However room size is the defining parameter - a small room will have a small volume of air to move, and a big sub will want to move more air than the room contains - this can dampen the dynamics of the speaker (something that constructors of sealed speaker & infinite baffle speaker cabinets know all about) - the rooms natural reasonance has a lot to do with how a sub will sound so matching the sub to the room is as important as matching the speaker cabinet to the speaker itself. While your sub didn't sound unpleasant in a small room, I suspect it would have sounded better with a smaller diameter driver, or in a bigger room, but if you are happy with the sound then that is the be all and end all of of it.  

Edited by Dean - September 18 2011 at 04:58

oliverstoned wrote: Catcher10 wrote: Thanks Dean....totally makes sense. But is it then my mind playing tricks on me, when I actually see the sub under a table or next to a setup (like in Olivers case)...that I can tell where the low end is coming from and if I move around it seems to "disappear", the sound that is. I have my Bose sub tucked behind a sofa at least 4.5m away from the small cube speakers.....I guess our ears can play tricks on us...... IMO a real sub is 38 cm diameter. Below, it just makes "boom boom".

oliverstoned wrote: Well, congrats too, it's a good purchase IMO. Do you have the stands provided by BW? If yes, are the speakers screwed on the stands, is it possible to fill the stands with sand?

Not yet. A bookshelf will do for now (which I now is not the ideal place to put them on but until next february when I move it will have to do). Then I'll get the stands... 

Well, congrats too, it's a good purchase IMO. Do you have the stands provided by BW? If yes, are the speakers screwed on the stands, is it possible to fill the stands with sand?

Edit: I screwed all my speakers on its stands, if not, there's much energy lost on bass attacks and forte. A big gain in clarity.

Edited by oliverstoned - September 16 2011 at 11:50

^ Nice!! Congrats......I think I heard those at the Magnolia HiFi in Bellevue, WA store...........Dude that is an awesome price!!!! CM1s not so much

oliverstoned wrote: Catcher10 wrote: Thanks Dean....totally makes sense. But is it then my mind playing tricks on me, when I actually see the sub under a table or next to a setup (like in Olivers case)...that I can tell where the low end is coming from and if I move around it seems to "disappear", the sound that is. I have my Bose sub tucked behind a sofa at least 4.5m away from the small cube speakers.....I guess our ears can play tricks on us...... It should not as extreme low is omnidirectional...or maybe it's because it's NOT real extreme low

Catcher10 wrote: Thanks Dean....totally makes sense. But is it then my mind playing tricks on me, when I actually see the sub under a table or next to a setup (like in Olivers case)...that I can tell where the low end is coming from and if I move around it seems to "disappear", the sound that is. I have my Bose sub tucked behind a sofa at least 4.5m away from the small cube speakers.....I guess our ears can play tricks on us......

That's the power of suggestion and how those tricks that the mind plays on us can affect our judgement of sound - things can sound better if they look better - it's like food, we cannot enjoy food that looks bad anywhere near as well as we do when it looks good - all of our senses come into play when our brains try and interpret the world.