Hi all,

I came to realize that my floorstanders will be greatly benefited if raised 10-20cm from the floor. Their design is peculiar as they are transmission line with a bottom port sitting on 3 adjustable spikes.

I’m really puzzled on what to place them on and I would appreciate some advice. My main thinking is to use a solid block of wood but unclear on whether it is the right material, whether it needs to be solid or hollow but also how they should be coupled/decoupled from the wooden floor. Generally my question is: is it better to be solid or hollow? Heavy or light? Coupled or decoupled from the floor? (again remember that the speakers will be sitting on it using spikes. To note that I have tried heavy ceramic base in the past and didn’t work for me (I thought that it reduced the liveliness of the sound) Thanks!

Try open frame then. Get some of these isoacoustics.com/iso-155-isolation-stands/ and then no need for the spikes.

There are as many opinions as there are retailers and at generally excessive prices. Rigid open stands seem to be the most preferred (check TM where there are many listings), spiked on the bottom and using blu-tack between the base of the speaker and the top of the stand. If your speakers have a port or TL underneath this should not be a problem on an open stand spikes or not. Your ear when seated should be at about the same level as the tweeter which should give a clue as the the height of the required stand. Stands for bookshelf speakers quite often utilize a wide hollow central pipe which some enthusiasts fill with lead shot and sand. Bigger speakers require a wider base and therefore four legs are more stable.

If the speakers are designed with a bottom port, then the height of port above the floor, can/should be tuned by ear to suit you & your room.

Then, you can optimise the interface - ie. the materials, a 'stand' etc if necessary.

DarkLantern blog - darklanternforowen.wordpress.com

Or tune by blocking/partially blocking the port.

Thanks, the TL port on the bottom requires a flat base surface underneath for the spikes to rest upon (essentially as the distance from the port to the flat surface increases the sound changes dramatically, even small changes in the height make a big difference). Also the base needs to be not more than 10-20cm which unfortunately is not standard so I need to make a diy solution. I will post a photo to help you understand better.

What makes you need to increase the height by 10-20cm over the normal height?

Is your couch 10-20cm higher than normal?

Let me explain Citroen :

These are peculiar but interesting speakers: they use a 4" full-range driver on top and below it a 2nd identical driver that starts to rolloff at 1000hz (for bass reinforcement). Apart from the 2 front ports it also has a transmission line that ends on a 3rd port on the bottom (you can see the curved bottom), the latter playing a huge role on a the overall sound adding weight and depth. In-terms of orientation they benefit from being a bit tilted on the back.

At some point I accidentally sat on the floor and noticed that the sound was significantly better (having a lot more weight and I thought more dynamic as well). I'm not sure how I would explain this, I'm thinking that sitting closer to the floor means that the transmission line port as well as the bottom driver play a bigger role and create a more balanced presentation. Regardless I since want to lift them so I can get that benefit while still sitting on my couch.

I should also clarify that I'm listening at a near-field setup.

Bottom ported speakers shouldn't need to be that high off the floor. I'd sugest by sitting on the floor you might have moved the listening position either in or out of a bass node. If possible maybe have a play around with moving speaker and/or listening position?

My thoughts too, got to agree with Harvey.

But have you actually tried them on temp stands eg books, bricks to see if you can replicate the sound by lifting them? All well and good if that works

Sitting closer to a room boundary (eg. floor, wall, corner) will increase bass (frequency depending on room dimensions).

Also, sitting lower will diminish HF (& maybe mids too) balance.

Maybe you can consider the ways that you may have available to address this - eg...

- tilting the spkrs back (upward) a little?
- moving the spkrs closer to a wall?
- a lower couch

DarkLantern blog - darklanternforowen.wordpress.com

If the speakers are true transmission line then in theory it shouldn't matter too much how far they are above the floor / close to the wall etc. I say in theory because there should be no sound coming out of the end of the line. In practice most TLs don't behave as they should and the port may emit sound like a tuned Helmholtz enclosure. (The stuffing in TLs should be placed at 1/5 intervals along the line length including immediately behind the drive unit and at the end termination. Again in theory it should intrude outwards at the termination but this has low WAF or wife acceptance factor.) The speaker placement in the ideal room can be determined by the Cardas equations (http://www.cardas.com/room_setup_main.php) which most often have them sitting about 1/5 from the back wall which has low WAF. Another convenient way to determine the optimum position is is to place ONE speaker in your listening position (e.g. on the couch) and then wander around where you would like to place your speakers and listen for the flattest sounding positions. This is easier to do that shifting your speakers around and will give the same result. Owen's suggestion of simply tilting your speaker back so that the tweeter is pointing at you on the couch is a good one - this is functionally the same as putting them on stands and also will help reduce excessive bass boom (room node stuff especially from the floor), if any.

p.s.I've just checked your speakers which are tall and slim so I doubt that you will need stands.

They are very complex to place as it’s not only the position that matters but also bottom port height from the floor and tilting that all influence the bottom end significantly (even small changes have a big impact). The main driver is already pointing at the listener but still a lower sitting position (at the lower LF driver height) seems to be working better (I know this contradicts standard practice but that’s what I hear). They are already tilted back as this works very positively as well. I have no doubt that they would benefit from some height but I’m not sure how much that would be so I’m experimenting a bit more with books and such (per Cintroen’s suggestion) and will report back.

Looking forward to your findings

Update on this one: so I’ve experimented with lifting the speakers and indeed it wasn’t working (as you guys had predicted). The problem was that the speakers required tilting back and given that I was listening very much near field did not have enough distance for that to work properly (that’s why I had the need to be lower in-terms if height - I hope I make sense). Solved however: I’ve moved the speakers back closer to the wall and further away from the listening position, low-end was significantly reinforced and now it is at the right distance to have the right balance when tilted back. Potentially a thin wooden base wouldn’t hurt but I’ve hinted and I didn’t get a positive reaction from my other half (she already thinks the speakers are too dominant), so I gave up as sound is pretty good already!

Good result

DarkLantern blog - darklanternforowen.wordpress.com

Dont argue with the war office as it will always result in pain...

A further thought on tilting the speakers which you suggest gives the best result. Your speakers are tall and slim and therefore not very stable especially if tilted back. This is not just an issue for stray dogs and children so let me explain. When the bass units in your speakers respond to a signal and move forward (and then back and then forward etc etc) the speaker cabinet moves in the opposite direction, albeit a minuscule fraction of a mm. However this does smear the sound as discovered by Richard Vandersteen, the designer of the long-running and excellent value-for-money Vandersteen Ce2 (now up to Mk 111). He is reported to have rung a friend very early one morning to excitedly exclaim the improvements that he heard when he 'jammed' a piece of dowel between the top back of the speaker and the wall, with just enough pressure to maintain the dowel in place. My suggestion is to make and outrigger base for your speakers (i.e. wider and much deeper than your speakers especially to the rear) and tilt these back with e.g. a pair of spikes on the front only. This will cure two problems but you will need to secure the new base to the bottom of the speakers. If they have spikes you can use the female thread.

Aug 19, 2020 11:47:00 GMT 12 peter0c said:

A further thought on tilting the speakers which you suggest gives the best result. Your speakers are tall and slim and therefore not very stable especially if tilted back. This is not just an issue for stray dogs and children so let me explain. When the bass units in your speakers respond to a signal and move forward (and then back and then forward etc etc) the speaker cabinet moves in the opposite direction, albeit a minuscule fraction of a mm. However this does smear the sound as discovered by Richard Vandersteen, the designer of the long-running and excellent value-for-money Vandersteen Ce2 (now up to Mk 111). He is reported to have rung a friend very early one morning to excitedly exclaim the improvements that he heard when he 'jammed' a piece of dowel between the top back of the speaker and the wall, with just enough pressure to maintain the dowel in place. My suggestion is to make and outrigger base for your speakers (i.e. wider and much deeper than your speakers especially to the rear) and tilt these back with e.g. a pair of spikes on the front only. This will cure two problems but you will need to secure the new base to the bottom of the speakers. If they have spikes you can use the female thread.

Really interesting and thanks a lot for your suggestion. They are solid oak so weight quite a bit and not so light as they look. The base they come with is already outrigger with spikes (if I understand correctly what that means): have a look at the photo above and it is a bit wider and deeper (although not significantly so), let me know if you mean something different!

Aug 19, 2020 10:38:09 GMT 12 andrewp said:

Dont argue with the war office as it will always result in pain...

Lol!

Good that they already come with outriggers and spikes. Possibly all you need to do is remover the rear spikes to give the required backwards slope!