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4-tier Mana Rack

Chris

Chris

pfm Member
A mate is having problems with his 4-tier Mana rack - it´s just not doing its job and the slightest touch to its uprights leads to a veritable seismic wobble in his bass drivers so he assumes it is affecting the sound under normal use. I have asked if he has gone over all the spikes etc. and he assures me all is correct and suggested he place his Sugden a21a on the bottom tier but no real joy. Any ideas about what he might be doing wrong ? I lent him my maglev Sound Will Spikes and the problem disappeared ipso facto but any other ideas ? Magnetic spikes perhaps ?
 
I have yet to hear of an application, industrial or otherwise (other than Hifi), where spikes have been used to reduce vibration.

Cars don't use them. Bridges don't use them, Buildings don't use them etc etc.

If you want to shift vibrations use different density materials. If you want to absorb vibrations turn them into heat ie. Sorbothane/similar or use damped springs, rubber band suspension, magnets, liquid or air to gradually reduce them.

Hifi has a love for the things. Worst thing you can do is to use them under TT's which is incidentally a good example of how a spike works ... (stylus) :)

Some elaborate cones are well intentioned but I still wouldn't choose them over the simplest Sorbothane or Squash balls cut in half or, on the other hand, something like Townshends Seismic Sinks.

The most effective part of a Mana Rack is probably not the trillion spikes but the little rubber pads that help securing shelves (assuming they use them).
 
Chris said:
A mate is having problems with his 4-tier Mana rack - it´s just not doing its job and the slightest touch to its uprights leads to a veritable seismic wobble in his bass drivers so he assumes it is affecting the sound under normal use. I have asked if he has gone over all the spikes etc. and he assures me all is correct and suggested he place his Sugden a21a on the bottom tier but no real joy. Any ideas about what he might be doing wrong ? I lent him my maglev Sound Will Spikes and the problem disappeared ipso facto but any other ideas ? Magnetic spikes perhaps ?
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Assume you're talking about a turntable on the top shelf causing this issue? Mana stands are 'designed' for use with suspended turntables, so wall mounting will be a better option if his turntable isn't suspended, or trying to decouple the top shelf.
 
LP12 on a solid floor. Mine is the same but 5 stacked soundstages rather than a rack. In my case you can rap your knucles on any of the metal parts and nothing happens. No, this is a "rack" thing.
 
I had my LP12 on a Mana rack, suspended floor for a while.

If I jumped up and down, heavily I could give it problems.
No problem otherwise
 
drummerman said:
The most effective part of a Mana Rack is probably not the trillion spikes but the little rubber pads that help securing shelves (assuming they use them).
Click to expand...
There are no rubber pads on Mana. The closest thing might be the two bitumen strips under each pane of glass.

To the OP, I strongly suspect a suspended floor (first), spikes have not fully pierced the floor-coverings (second) or poorly levelled stand (third). I have my LP12 on top of my 5-Tier Mana on concrete floor. It is literally rock solid and does not budge even if I bump the stand.

If the floor is suspended, the TT will need to be mounted on a wall shelf.

If the spikes are "resisted" from putting the full weight of the stand onto solid substrate because of thick carpet or underlay, I'd suggest cutting an X over each piercing or driving screws into the (wooden) floor and resting the spikes on them instead.

The stand should not rock, even when unloaded. If it does, it needs to be levelled first, or all bets are off.
 
Self drilling Hex Head Tapper Screws are much more forgiving of placement than phillips screws and the lip on the top will stop the spikes from sliding off.

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Chris said:
LP12 on a solid floor. Mine is the same but 5 stacked soundstages rather than a rack. In my case you can rap your knucles on any of the metal parts and nothing happens. No, this is a "rack" thing.
Click to expand...

It's not clear to me what your concern is. You mention your friend is getting movement of his woofers when tapping on the stand. Is this while a record is being played or what?

If I rap on my Mana support while a record is playing the record will skip. There is a certain amount of springiness to a Mana support and movement of the rack when rapping it with your knuckles is not something I find unusual. It's also something I don't do while playing records so is not a concern to me.
 
Hi John, No I´m not worried about being able to rap my Mana with my knuckles, as you say it´s not something one would normally do. It´s my mate´s rack which does not allow the slightest caress with your findertips withut setting off an enormous reaction in the woofers. What set it off was bearing witness to the effect placing some maglev spikes under his LP12, placed on the top shelf of said rack and how with them in place sound improved and the woofer wobble disappeared completely. This does not happen with my phase 5 sound frames and stages under my LP12 hence my query if racks were not so effective as normal Mana stages. Considering the sheer weight of a loaded 4-tier rack it seems impossible. I think James is probably right about soemthing being seriously out of kilt on the large sound stage he has under his rack.
 
I think an amp rack would react differently to touching than sound frames and soundstages used alone. If I were your friend, I wouldn't be concerned unless he has some fetish to touch his Mana amp rack while playing records.
 
I would have said you were right had it not been for the sudden improvement in the sound when he put the maglev spikes under his LP12. they led him to suspect that some sort of feedback was affecting his system through the rack.
 
Chris said:
I would have said you were right had it not been for the sudden improvement in the sound when he put the maglev spikes under his LP12. they led him to suspect that some sort of feedback was affecting his system through the rack.
Click to expand...

Have you tried the maglev spikes under your LP12 and did they change the sound? Do either turntable use the Trampolin base?
 
Chris said:
His uses the Trampolinn 2 base-
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Trampolin was something never recommended with Mana. I don't use one with mine? The suspension of the LP12 and Trampolin along with the resonance of the Mana rack is likely not a good thing.

Do you use the maglev feet with your LP12?
 
Just to refresh my memory. I know the spike nuts should go beneath the horizontal cross members of the sound frames with boards and above the corner pieces on the mini table to support the glass of the final phase. But with the racks should they go under the metal part which holds the feet spikes in contact with the floor and also beneath all the metal corner pieces supporting wach piece of glass.
 
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