Too isolated?

[Bribase]

Hey guys

I have a general speaker setup question. I'm running my foreplay through a Linn Klout to some Kef RDM2s in my living room at the moment. I'm playing around with different configurations with my speakers and want a little advice. My RDM2s sit on some chunky (but cheap) stands that I mass loaded with white spar rocks (they have a natural pyramid shape so they slot together and don't rattle). My RDM2s sit on the top plate of the stands with foculpods separating them, the stands are isolated from the floor with built in spikes, my floor is just standard flooring over timber.

I've just lately sat my stands on some concrete blocks to see if I could further isolate my speakers to improve the imaging and define the bass more. This has worked well but I'm missing so much of my bottom end that I'm not sure if I'm happy with it. Of course so much of the bass that you hear on your hifi is often felt through the floor as opposed to your ears so I'm wondering if a persons speakers can ever be too isolated.

I know that it's a deeply subjective question that I'm asking here. Is there another option that I could try? Maybe some giant blocks of wood to sit my stands on? Or maybe losing the concrete blocks and mass loading my speakers with something heavier? The RDM2s are well known for great imaging but are notorious for missing some low end. What are your experiences? Which would you prefer? A slightly less well defined but full sounding bass or a very controlled but somewhat weak one?

Thanks for the help!

B

[tbbenton]

I remember being encouraged to put spikes on my speakers.

I suppose you already verified that the channels in phase.  You've probably already played with speaker placement: away/close to the wall/corner.  Final obvious thought -- which can make a huge difference -- get a powered sub or a few.

[ssssly]

First blush I would be concerned with how high off the floor the speakers are. Don't know how thick the blocks are but raising speakers too high off the floor can play havoc on imaging and bass. You can usually get the bass back by repositioning. But not much you can do for imaging if your speakers, particularly tweeters, are too far above ear level.

I'm also not a huge fan of concrete for isolation and deadening purposes. Some love it but it reflects a bit too much for my taste.

I recently have been experimenting with different speaker coupling materials. My favorite at the moment is brass spikes with wooden disc footers backed on the floor side with sorbothane. Has very little tactile transfer into the floor and sounds very tight but natural and warm.

[Grainger49]

To combine Tom's and Sly's posts, any reflective surface will help "augment" the bass response of speakers.  That would be the rear wall, side wall, floor and/or ceiling.  I bet you won't be using the ceiling. 

But here is the first thing you need to get done, your tweeter should be at ear height.  If that eliminates your bass response then the speaker could be lowered to help the bass.  But then you need to tilt your speakers up to aim the tweeters at your ear height.  This will help the imaging and soundstage.

If your speakers were out of phase there would be no image in the center.  But then if only the woofers were out of phase you would just lack bass.  To check this you can put them face to face.  If the sound drops they are out of phase, if it gets louder they are in phase.  Just to be certain swap the leads on only one speaker and notice the results.  Unless you have been into the speakers I think there is little chance that the woofers only are out of phase.

I don't think that the problem is related to speaker isolation or vibration control.  I have always thought that the majority of sound produced comes from the driver and port.  I think the vibration control comes after you get the system to image correctly and get your bass response as even as possible.

A final question, what is the speaker arrangement like?  That is, how far into the room from the front wall are they, how far from the speakers are you and how far from the rear wall do you sit?