Herzan/Table Stable "Active" Isolation table.

[microstrip]

Hi Micro - interested in learning more. When you say a passive system has a reaction time of 2-10 seconds, are you referring to passive systems that drain vibration like Finite Elemente racks, or SRA Ohio Class platforms?

The reason I ask is I am wondering what happens if you clamp something completely in inert, elastomer covered vices...obviously passive, but it is preventing the chassis from moving [almost] at all. Is it better (in theory) to nearly instantaneously react to any vibration with a countermovement (the vibration equivalent of noise cancelling headphones)...or to prevent the device from moving almost at all in the first place, by clamping it in some form of well-designed vice?

I was just copying from the table in the Hertzan link comparing the performance of active versus passive. I admit that by passive the are considering the classical pneumatic tables with valve servo's - these thinks can be slow to recover. But this parameter is not relevant to audiophiles unless you like jumping on the table (yes, I tried it on my old active Vibraplane to be sure it was working properly - it is a funny sensation!)

AFAIK the main problem with passive elastometers is that they are effective in a limited range of frequencies, and have little efficiency at very low frequencies. Finite Elemente uses piezzo sensors and actuators to cancel vibrations of their shelves, but as far as I could understand do not have isolation from floor vibrations.

 

[microstrip]

Francisco, I agree with your point that you could have a house situated on land that has some strange acoustic properties. I think it would be far more common for people who live on busy streets with their houses situated close to the road and other houses to hear effects from their neighbors and the road noise. But that is why I previously stated that people who have lively structures will benefit the most from the tables. I'm sure there are some benefits to be had by all.

I also agree with you, but would also agree with someone stating the opposite - lively structures are lighter and have higher frequency resonances, blocking very low frequencies. These less low frequencies can be solved using passive tables. But the people living in very massive and rigid structures have problems at very low frequencies, and they should need active tables. Strange hobby, where we must agree with opposing views.

Unfortunately I spend my hifi budget for the season buying a PS Audio P10 - although I have a nice proposal for an Halcionics Micro 40 active isolation table equivalent to the TS-150, I have to resist for sometime ... But I am sure the Forsell will love it!

 

[PeterA]

actually the Herzan active isolation does not care where the resonance is coming from. whether from the rack below, the gear sitting on it, your finger tapping the platform, or the air pressure waves; it senses them all as resonance to be cancelled out. it reacts to input from it's sensors.

It must only react at the platform surface. How can the Herzan sensors react to an airborne vibration hitting the arm or platter and cancel it BEFORE that vibration gets to the cartridge (from the arm or platter)? I would think that the Herzan can only react to vibrations that reach its top surface, airborne, floor born or draining away from the equipment. Vibrations hitting the cartridge from the arm and from the platter through the record surface effect the signal which is then amplified and transformed by the speakers into sound waves.

Are you suggesting that the Herzan can get these vibrations from the arm or platter before they effect the cartridge? That would be incredible, if true.

I guess another case is the notorious vibrations from all of the adjustments in the TriPlanar arm. Owners remove things like the anti-skate mechanism so the vibrations don't effect the signal at the cartridge. Would the Herzan make the removal of these vibration creating bits and pieces not necessary. Another example would be the finger lift on my SME V-12 arm. I never installed it because of a fear of the vibrations created by its addition, right at the headshell and dangerously close to the cartridge. How would the Herzan or any active isolation solution effect something like that?

 

[PeterA]

all you have to do is to stand next to the Herzan with the active isolation engaged and view the LCD readout with the lines of noise displayed. this display shows the noise which is being cancelled. with no music playing there are little jiggles to the lines constantly. that is the background noise of the room and system. then clap your hands loudly and those lines jump with the clap. that is air pressure waves hitting the sensors and being cancelled.

like any other resonance, there is not necessarily 100% cancellation, but clearly the air born resonance is getting sensed and cancelled to some degree.

as far as the word 'shield', i'm not sure that fits. the Herzan can only deal with resonance it senses. you would have to have an acoustic enclosure around the turntable to 'shield' it. to the degree that air borne resonance hits the turntable and causes resonance down thru the turntable and is sensed by the sensors thru the shelf it can act to cancel that resonance.

I think this addresses my and Mep's question. IF the sensors under the Herzan top surface plate feel the vibration, they can then react to try to cancel or dampen it. But this is far different from dampening vibrations hitting the arm or platter that don't make it to the Herzan BEFORE first hitting and effecting the cartridge. We then hear that through the speakers as distortion and the Herzan can't help with that.

 

[PeterA]

Mep, I concur. I contributed a little while ago that I'm sure active isolation is MUCH better than passive in isolating the tt from ground borne vibrations - 6 axes of isolation, and more instantaneous reaction time has got to be much more effective than my old standard fixed rack, or somewhat more effective than my Symposium Isis that via ball bearings/opposing magnets does a great job in the horizontal plane.
I'm going to go out on a limb here and say that my 5 layers of isolation in my Isis could well be a better passive solution than Mike's solid Adona rack using Wave Kinetics passive isolating footers. Hence, when he then uber upgraded to active isolation he got a more massive upgrade than I might be likely to get going to active from Symposium.
From my discussion with one of active isolation co. people, it's dealing with floor borne (we can all agree on this); but doesn't purport to deal with direct airborne ie sound from the spkrs (your point, and mine, mep) - however it does purport to isolate from bass nodes and standing waves that 'collect' or 'pool' in the room. Imho, I still think this is dealt with more thru floor borne isolation since such subsonic waves are likely to energise the floor more than the walls, structures and the air itself. So now we have active isolating from the floor in two ways, ground borne vibration eg footfall, traffic, building creep, neighbours - AND standing waves etc attenuated via the floor. If these waves are indeed< 5Hz or even <1Hz, active will be MUCH better suited than passive.
BUT, vibrations CREATED by the tt eg motor torque, spinning platters, arm pivoting/ or cd eg spinning disc, laser sled movement, surely cannot be attenuated totally since they're continuous and a NORMAL function of the device.
And no-one has sufficiently explained how the most delicate vibration of all must NOT be inhibited ie movement of stylus in groove which picks up the info sent to the phono. Just HOW does active 'know' what is 'bad' or 'good' vibrations?
SO in conclusion, if active is dealing with subsonics in the room from standing waves etc, IN ADDITION TO regular ground borne noise, this will give it thee edge over passive. How much, YMMV. In my case, I'm using Spatial Computer Black Holes to attenuate nodes/standing waves, and my building is as solid as they come, so a positive result for active demo over my Symposium would be an eye (ear) opener.

I think this pretty much explains the limits of active isolation. And Mike wrote that it can make things much much much better, but not perfect.

 

[rockitman]

I think this addresses my and Mep's question. IF the sensors under the Herzan top surface plate feel the vibration, they can then react to try to cancel or dampen it. But this is far different from dampening vibrations hitting the arm or platter that don't make it to the Herzan BEFORE first hitting and effecting the cartridge. We then hear that through the speakers as distortion and the Herzan can't help with that.

Peter,

Think accumulation of vibration hence a resonance starts. While not at the exact time the music hits the cart, the herzan does dampen accumulating vibration/resonance and prevents it from building up when compared to no isolation. That is why some TT's may do better than others like my table and Mike's which drain the vibration through their feet, which are in direct contact with the Herzan's shelf.

 

[spiritofmusic]

Christian, despite my mild skepticism active is the all-singing panacea to vibrations, that proponents like you and Mike claim, I think you and I have summarised it's likely effects. If we take a source component, it's generating continuous vibration, eg tt/arm (motor torque/spinning platter/arm movement, and in my case air bearing supply pressure), or cdp (spinning disc, laser sled movement). This is ongoing and must generate a steady flow of unwanted noise. A good proportion of this will feed thru the cart/stylus or laser head, and also the structure of the tt/arm or cdp, then the feet, then interfacing with the shelf. This morass of noise will set up a continuous feedback loop transmitting a fair amount back into the component and undesirably thru the stylus or laser. If active isolation can compensate for this haze of noise at the component-shelf interface, maybe indeed a great deal will be attenuated and not feed back. So yes Christian, the shelf is not necc responding to an individual vibration but an aggregate 'haze'. Similarly, standing waves/bass nodes, and good old fashioned floor-borne vibrations from traffic, building/floor creep, neighbours etc which add to this haze at the interface of component-shelf will be similarly attenuated.
We should agree that for all that active purports, it's job is still done at the component-shelf interface, and not anywhere other than this, ie not direct from the room.
Just feel it's time to knock on the head the idea that there is isolation of the tt/arm or cdp player DIRECTLY from such vibrations. This seems impossible. It MUST happen via the component-shelf interface, and maybe the sub-1Hz 6 axes active isolation really is successful at draining the aggregate of noise/haze from recycling back into the component.
Re amps etc, maybe components really are microphonic, esp. tubes ( I myself am likely to go to all tubes, and that's a LOT of glass that could vibrate (un)sympathetically. Re SS, maybe components like big Duelund caps (size of Coke cans) need cossetting.
In response to a previous comment directed at Mike, so much in the high end always seems to be redefining the SOTA, incl. your comments. I've got a very revealing, tonally satisfying system which responds to any change in components in the chain, and system-wide upgrades, but other than power matters, changes have been hit and miss, gradual evolution being the best way to describe my progress, often v.incremental. However, EVERY change you've made has been near-revolutionary. The closest I've got to this was my change to balanced power, and that was a DISASTER for 6 wks until 80kg of Cu in the transformer bedded in, Even then, even though it's been an all-round positive outcome, it's not changed my total enjoyment of the system. Certainly your comments on this and similar upgrades suggest an almost-infinite possibility of improvements. personally, I'm hoping from a more realistic 30% over time.

 

[Bruce B]

I'd love to hear the effect (if any) at low volumes or even through headphones! I bet there is none.....

 

[rockitman]

However, EVERY change you've made has been near-revolutionary. The closest I've got to this was my change to balanced power, and that was a DISASTER for 6 wks until 80kg of Cu in the transformer bedded in, Even then, even though it's been an all-round positive outcome, it's not changed my total enjoyment of the system. Certainly your comments on this and similar upgrades suggest an almost-infinite possibility of improvements. personally, I'm hoping from a more realistic 30% over time.

revolutionary ? Not really. It was simple...When I heard the value of a fully treated stillpoints setup in my system, the next progression was naturally SOTA Active isolation for the TT. I have learned through this process how important correct isolation is. In the past I fluffed it off. I find it quite amazing that when I think I have hit the glass ceiling for lack of a better expression, something comes along and I burst through.

 

[spiritofmusic]

No disrespect, but "bursting thru" suggests 'revolutionary', in the sense of 'not evolutionary' eg The Beatles, Bach etc being revolutionary (we certainly couldn't go back to before their music). Maybe we're getting back to the realms of only uber expensive/overkill equipment eg Wave Kinetics, SME, Clearaudio, Krell, Pass Labs, Dartzeel, Wilson, Evolution Acoustics, and even here, only top of the line models, to have sufficient headroom in performance, to be taken to such exalted levels by upgrades like active isolation.
I would love to have had such a breakthru moment myself, but other than a smile of contented satisfaction at getting power right, my experiences have been incremental. The sound of my system has become enhanced rather than dramatically changed. My comment was directed mostly at Mike, and again no disrespect to him, but he's had several upgrades to his system I've followed on A'gon that have dramatically moved the goalposts.
The more I hear of earth shattering, the more I need to analyse. Maybe a real case of YMMV.

 

[Mike Lavigne]

I'd love to hear the effect (if any) at low volumes or even through headphones! I bet there is none.....

anytime Bruce, i'd enjoy getting your take when you have the time.

I certainly agree that greatly reducing speaker feedback is the major thing it does better than any other method, but it's more than that. it removes a good amount of the noise signature of the room too. you can easily 'see' the noise on the LCD screen that it is removing when there is no music and the room is dead quiet to my ears.

I do not have a method to hook up headphones, so you would need to bring that along with the headphones. we can certainly listen at low volumes thou.

today I had visitors who were here for 3 hours, we listened to quite a bit softly recorded classical pieces, such as solo violin and solo acoustic guitar, where the 'active isolation magic' was clearly evident and speaker feedback was minimal.

 

[beaur]

Nice thread. Lots of interesting information. I can try to add my perspective from someone who has used vibration control for work (on a boat). Just as a point of reference I have a passive table under my modest TT and I think it does a great job. My not have bought an active if I could have afforded it as to me passive is most of the way there with 95% of the results.

1. If you haven't fine tuned your system to eliminate other issues ie room etc, vibration control will help but it's just a band aid. Fix the other bleeding wounds first then take care of controlling vibrations with purpose built active or passive control system.
2. There are some situations where passive will do a better job but assuming #1 active may be the choice for that last 1% of refinement. Don't fret if you can't afford active as there are some damn good passive systems around.
3. Remember to dress all cables etc hanging off the support. Does no good to spend $$ on a VC table and let vibration back into the system via cables.
4. If you like what a table does and want to expand to your entire system consider a solution for your entire rack. Most companies make something that will easily support your rack and equipment.

Also as far as airborne vibration cancellation; While most VC tables can counteract it, a TT on top of a VC table for example, that the sensors are seeing these vibrations after they have already passed through your equipment. What they are canceling is the resonance. If you believe that airborne vibrations affect say the cartridge / LP interface then the damage has already been done you are just preventing it from getting worse.

 

[Jaguar]

I'd love to hear the effect (if any) at low volumes or even through headphones! I bet there is none.....

Mike, this sounds like an interesting experiment to test how much of an impact the lowest frequencies are having on your sound. In reading about the specs on some of the websites it occurred to me that I hadn't given much thought to what's going on down as low as 1Hz...not much action out of your speakers at that level, but maybe from that volcano you live on top of.

I don't know if your system requires 50ohm connectors on a headphone amp. If not, Andrew has my Bakoon HPA-21 headphone amp, which you could take after he's done. The current option on the Bakoon is one of the most resolving outputs I've ever encountered, for listening tests.

 

[treitz3]

3. Remember to dress all cables etc hanging off the support. Does no good to spend $$ on a VC table and let vibration back into the system via cables.

Hello, beaur and good morning to you. Would you mind clarifying what you mean by "dressing" all of the cables please?

Tom

 

[Mike Lavigne]

Mike, this sounds like an interesting experiment to test how much of an impact the lowest frequencies are having on your sound. In reading about the specs on some of the websites it occurred to me that I hadn't given much thought to what's going on down as low as 1Hz...not much action out of your speakers at that level, but maybe from that volcano you live on top of.

I don't know if your system requires 50ohm connectors on a headphone amp. If not, Andrew has my Bakoon HPA-21 headphone amp, which you could take after he's done. The current option on the Bakoon is one of the most resolving outputs I've ever encountered, for listening tests.

i'm game for the investigation, but i'm not removing the Herzan in that process. it is a royal pain to actually remove the Herzan from under my gear. and moving gear around always has the potential for bad things to happen.

2 weeks ago I did have a couple friends here and we did remove the Herzan from under the NVS doing an A-B-A. it was laughingly better with the Herzan. I was already convinced, but i'm not going there again.

I have no need myself to prove anything to myself, and am not even a little curious about it. but if Bruce or you (or Andrew) want to try headphones and we can switch the Herzan isolation on and off i'm game for that.

anyone is free to buy their own Herzan (or Halcyonics) and do all the experiments they might enjoy. knock yourself out.

all anyone has to do is spend a listening session with the Herzan underneath their gear. it's not subtle, it's a whole new deal.

as far as connecting a headphone amp; it's easy with the dart pre. either RCA, XLR or 50 ohm BNC outputs. the most practical is the fixed volume 'tape/record out' RCA. then you can quickly mute the speakers in and out for A/B's. when I had my 'big-boy' headphone gear a couple of years ago I did lots of comparing to my speaker system and it worked great.

 

[beaur]

Hello, beaur and good morning to you. Would you mind clarifying what you mean by "dressing" all of the cables please?

Tom

I think someone mentioned it earlier but essentially boils down to 2 factors:

1. Don't impede the operation of the VC table by laying a cable across the table top and base or placing any tension on the cables that stops the motion of the top.

2. Don't route the cables near/on any possible source of vibration. Heck at these levels I wouldn't even cross signal and power cords if I could avoid it.

Difficult to do with a TT but I have seen a few installation place the power cords above the instrument on the VC table and create a loop with slack so there is no pulling.

Basically it comes down to good cable management which in my book falls under my #1 and should have been done before installing the VC table.

Beau

 

[spiritofmusic]

Mike, you alluded to the fact that stiffness of cables could easily negate the effects of active isolation. With all those cables/cords going in/out of your Dart pre, how have you got around this?
If the only way you could have demoed the Herzan with your tt was to put it all on the floor, maybe just with a kitchen worktop granite slab underneath, or a low tech light spiked single shelf, do you suspect the Herzan would have sold itself? Unfortunately I can't disable the passive horizontal isolation in my Symposium, and I don't have access easily to another fixed rack, so it's floor level or nothing. There's no point in me even contemplating the comparison if this solution is inherently flawed.
Where do you think you might go next? I'm getting good results with Entreq Tellus grounding, and Miguel raves about his Troy grounding in similar terms to your positives on active isolation. Entreq has been a really good complement to my 8kVA balanced power transformer, and the price is reasonable in comparison to my total system cost. Miguel's Troy is at the exalted stratosphere that Herzan/Halcyonics occupies.
Sorry this is off-thread.

 

[treitz3]

Hello, beaur and good morning to you. Would you mind clarifying what you mean by "dressing" all of the cables please?

Tom

I think someone mentioned it earlier but essentially boils down to 2 factors:

1. Don't impede the operation of the VC table by laying a cable across the table top and base or placing any tension on the cables that stops the motion of the top.

2. Don't route the cables near/on any possible source of vibration. Heck at these levels I wouldn't even cross signal and power cords if I could avoid it.

Difficult to do with a TT but I have seen a few installation place the power cords above the instrument on the VC table and create a loop with slack so there is no pulling.

Basically it comes down to good cable management which in my book falls under my #1 and should have been done before installing the VC table.

Beau

Gotcha'. Thank you, sir.

Tom

 

[MylesBAstor]

Mike, you alluded to the fact that stiffness of cables could easily negate the effects of active isolation. With all those cables/cords going in/out of your Dart pre, how have you got around this?
If the only way you could have demoed the Herzan with your tt was to put it all on the floor, maybe just with a kitchen worktop granite slab underneath, or a low tech light spiked single shelf, do you suspect the Herzan would have sold itself? Unfortunately I can't disable the passive horizontal isolation in my Symposium, and I don't have access easily to another fixed rack, so it's floor level or nothing. There's no point in me even contemplating the comparison if this solution is inherently flawed.
Where do you think you might go next? I'm getting good results with Entreq Tellus grounding, and Miguel raves about his Troy grounding in similar terms to your positives on active isolation. Entreq has been a really good complement to my 8kVA balanced power transformer, and the price is reasonable in comparison to my total system cost. Miguel's Troy is at the exalted stratosphere that Herzan/Halcyonics occupies.
Sorry this is off-thread.

It's not a small point! That's why I hate heavy AC cords. Even if you're using something like tiptoes, these heavy cords can yank or pull the component off the cones. I even have to be careful that the AC cord doesn't interfere with the free movement of the R2R deck on the Symposium Isis.

There's also another problem that I ran into, and that may be peculiar to the cj gear (?). For some reason, the bottom of the unit isn't absolutely flat and all four feet don't make contact with my SRA VR Isobase. So I have to wedge something under the fourth footer to ensure there's good contact and the unit doesn't rock/resonate. It does make a big difference. On just the three feet, the sound is decidedly edgier.

 

[mep]

Basically it comes down to good cable management which in my book falls under my #1 and should have been done before installing the VC table.

Beau

Uh, how do you dress all of the cables before installing the VC when you have to place something on top of the VC and then dress the cables??