Blu tack under speakers

[giggsy1977]

Ok, I'm about to ask an 'unusual' question, so no taking the mickey please! We all know that a blob of blu tack under our stereo and home cinema speakers can add tighter bass and detail to sound, but just how big a blob? I appreciate we aren't talking golf ball size, but are we talking pea sized or slightly larger? Press it flat or leave as a ball for speaker to sit on? Does speaker size make a difference? I know this isn't an exact science and I may be coming across as a little odd with this question, but was just wondering really! Ok, let the mickey taking commence...!!!

 

[Anonymous]

I use the minimum amount I can get away with to achieve good fixture and stability. If the theory suggests that the drivers can move a speaker in a rocking motion on their stands then I imagine the same movement would apply on lumps of soft bluetak.

 

[SteveR750]

I am intrigued by the point of using blu tak, when the stand have spikes supposedly to drain away resonant energy from the enclosure. All Blu tak will do is decouple them, thus rendering the spikes pointless surely? (other than to assist in levelling).

 

[Anonymous]

SteveR750:(other than to assist in levelling)
...and not knocking them off. I'm not sure about the physics as I've heard a few different takes on it. The knocking off thing has saved them twice now; bloody careless house viewers...

 

[SteveR750]

Personally I have concluded that most of the "physics" bandied around in hi fi is tosh. There is a reason why people write about things instead of actually makeing them....

 

[Anonymous]

SteveR750:Personally I have concluded that most of the "physics" bandied around in hi fi is tosh. There is a reason why people write about things instead of actually makeing them....

That seems like a pretty reasonable conclusion given most of the things I've read, or more importantly, heard. [EDITED BY MODS - HOUSE RULES]http://www.audioholics.com/educatio...ker-spikes-and-cones-2013-what2019s-the-point

 

[idc]

It is such a simple and easy to do upgrade that it is just a case of try it and see. I used enough to make a 2p sized blob when squashed. It made for a small tightening of the base and secured the speaker from a small child.

If your stands are spiked at the top I would go with spikes over blu tack. My understanding is that speaker stands are not there to drain away energy from vibration. Instead they are to provide a solid, level surface where all vibrations are within the speaker. Speakers are designed to vibrate, enclosure and all, and so produce their sound. To keep the sound true to what was intended you do not want any vibration to 'drain away'.

 

[Anonymous]

idc:Speakers are designed to vibrate, enclosure and all/P>
But surely any energy lost to cabinet vibration is simply energy lost from the cone attempting to create a sound wave. Thus, it's bad.

 

[SteveR750]

idc:
It is such a simple and easy to do upgrade that it is just a case of try it and see. I used enough to make a 2p sized blob when squashed. It made for a small tightening of the base and secured the speaker from a small child.

If your stands are spiked at the top I would go with spikes over blu tack. My understanding is that speaker stands are not there to drain away energy from vibration. Instead they are to provide a solid, level surface where all vibrations are within the speaker. Speakers are designed to vibrate, enclosure and all, and so produce their sound. To keep the sound true to what was intended you do not want any vibration to 'drain away'.

The theory is that by providing a solid surface on which the cabinets can sit with minimal deflection caused by the driver, which is essentially what "draining" or coupling the speakers to a solid floor is doing. It also helps reduce the unwanted interference from the cabinet causing coloration.

 

[Clare Newsome]

SteveR750:Personally I have concluded that most of the "physics" bandied around in hi fi is tosh. There is a reason why people write about things instead of actually makeing them....

Our technical editor has made some rather impressive speakers, incidentally

 

[SteveR750]

Clare Newsome:
SteveR750:Personally I have concluded that most of the "physics" bandied around in hi fi is tosh. There is a reason why people write about things instead of actually makeing them....

Our technical editor has made some rather impressive speakers, incidentally

Hence the smiley! Though i was having a prod at the Peter Belts of the world rather than the Steward/Messenger/Golds......

I seem to recall that the AR 18BX speakers that I once owned and were once well liked in their day were partially designed by one of the more respected journos of the day whose name escapes me but I thought they were pretty good. I went to A&R Cambridge (as it was then) and Wharfedale for job interviews when I graduated and quickly discovered that was a lot more electronics in speaker design than materials engineering (that I had studied), so that put and end to that.

 

[John Duncan]

SteveR750:Clare Newsome:
SteveR750:Personally I have concluded that most of the "physics" bandied around in hi fi is tosh. There is a reason why people write about things instead of actually makeing them....

Our technical editor has made some rather impressive speakers, incidentally

Hence the smiley! Though i was having a prod at the Peter Belts of the world rather than the Steward/Messenger/Golds......

I seem to recall that the AR 18BX speakers that I once owned and were once well liked in their day were partially designed by one of the more respected journos of the day whose name escapes me but I thought they were pretty good. I went to A&R Cambridge (as it was then) and Wharfedale for job interviews when I graduated and quickly discovered that was a lot more electronics in speaker design than materials engineering (that I had studied), so that put and end to that.

Ooo I still have some AR18BXs. They're tosh (now)

 

[pwiles1968]

I just bought a small slab of White Tack (I just had to be different) and cut it in to 8 equal size segments put 4 under each speaker, stability was a little higher priority that any potential acoustic benefits of spikes with a 6 and 10 year olds around as careful as they are you just can not risk it, I love my kids I would hate to have to sell them to get a new pair of speakers

.

 

[chebby]

SteveR750:I am intrigued by the point of using blu tak, when the stand have spikes supposedly to drain away resonant energy from the enclosure. All Blu tak will do is decouple them, thus rendering the spikes pointless surely? (other than to assist in levelling).

Blu-Tack has non-newtonian properties so despite being squidgey, it is hard under compression and is completely different to rubber feet as far as vibration is concerned.

Also it stops speakers falling off things.

 

[SteveR750]

chebby:
SteveR750:I am intrigued by the point of using blu tak, when the stand have spikes supposedly to drain away resonant energy from the enclosure. All Blu tak will do is decouple them, thus rendering the spikes pointless surely? (other than to assist in levelling).

Blu-Tack has non-newtonian properties so despite being squidgey, it is hard under compression and is completely different to rubber feet as far as vibration is concerned.

Also it stops speakers falling off things.

Yes thats true it is anisotropic to a degree, but not that much at 50Hz

 

[idc]

igglebert:idc:Speakers are designed to vibrate, enclosure and all/P> But surely any energy lost to cabinet vibration is simply energy lost from the cone attempting to create a sound wave. Thus, it's bad.

My understanding is that when designing a speaker how the cabinet vibrates is taken into account and that is adapted to help produce the overall sound. The cabinet construction style and shape is part of the sound. Thus some are fully enclosed, others have bass ports (front and/or rear) and others have irregular shapes etc, etc. But the one thing that they all have in common is not to vibrate along with what they are on.

 

[Anonymous]

Clare Newsome:

Our technical editor has made some rather impressive speakers, incidentally

Any chance we can see these speakers? He should make a post

 

[survivor]

Just four small blobs under mine. Suprising how well it holds the speaker. I`d say slightly larger than a pea. Somewhere between a pea and a broad bean.

 

[Anonymous]

idc:
igglebert:idc:Speakers are designed to vibrate, enclosure and all/P> But surely any energy lost to cabinet vibration is simply energy lost from the cone attempting to create a sound wave. Thus, it's bad.

My understanding is that when designing a speaker how the cabinet vibrates is taken into account and that is adapted to help produce the overall sound. The cabinet construction style and shape is part of the sound. Thus some are fully enclosed, others have bass ports (front and/or rear) and others have irregular shapes etc, etc. But the one thing that they all have in common is not to vibrate along with what they are on.

Whilst I agree with what you're saying I suspect that a perfect world speaker would result in zero energy lost into the cabinet and all energy becoming sound waves. Design can tend towards that but can probably never achieve it, so the effects of cabinet etc, are 'designed into' the sound. Dunno, I'm no expert.

 

[SteveR750]

igglebert:idc:
igglebert:idc:Speakers are designed to vibrate, enclosure and all/P> But surely any energy lost to cabinet vibration is simply energy lost from the cone attempting to create a sound wave. Thus, it's bad.

My understanding is that when designing a speaker how the cabinet vibrates is taken into account and that is adapted to help produce the overall sound. The cabinet construction style and shape is part of the sound. Thus some are fully enclosed, others have bass ports (front and/or rear) and others have irregular shapes etc, etc. But the one thing that they all have in common is not to vibrate along with what they are on.

Whilst I agree with what you're saying I suspect that a perfect world speaker would result in zero energy lost into the cabinet and all energy becoming sound waves. Design can tend towards that but can probably never achieve it, so the effects of cabinet etc, are 'designed into' the sound. Dunno, I'm no expert.

Indeed but in the real world impossible of course despite bracing, bitumen or other internal dampening treatments, curved backs, etc etc; so the best thing to do is to try to resist the movement as much as possible, hence the logic of stiff heavy stands coupled to a high mass (the floor) with spikes. Its possible though that the speaker may be designed as a closed loop in the way the Linn Sondek was, in which case blu tak and anything else squidgy would be wholly appropriate......

 

[idc]

From the site; Jamo R909 speaker review. Jamo's take is not to have the speakers placed in a box at all.

 

[SteveR750]

well of course not, theoretically you require a infinite baffle. In practice this means putting the drivers into a box.

 

[Anonymous]

Back in the day when I first started reading What HiFi it was always recommended to use Blu-tak under speakers. It was said to provide resistance to the vibrations, keeping the speaker in place so that only the cone moved forward and back and not the enclosure. The analogy "Like trying to run in water." was often used to describe how it affected the vibrations.

 

[JoelSim]

I find that if you split a blob into 3 and plait it, it also serves to reduce the RFI effects present in all closed circuits as well as affixing the speaker to the stand membrane upper.

ÿ

 

[Anonymous]

If you apply a small pea sized bit behing each ear, on the lobe preferably the depth of the midrange is improved by at least 28% maybe slightly more

got to be blue stuff though not white the white muddies the bass.