Turntable Isolation or Coupling?

Discussion in 'Audio Hardware' started by MaJoon, Jul 10, 2018.

Thread Status:
Not open for further replies.
  1. JOnny Cox

    JOnny Cox Forum Resident

    Location:
    Bridgend
    Thanks for that I previously had speaker stands spiked onto a layer of carpet underlay so will try going back to that and compare. I must say the bamboo board has made a good improvement under my Rega turntable however. See previous post September 15 if interested.
     
  2. SandAndGlass

    SandAndGlass Twilight Forum Resident

    Agree, what exactly are they isolating from. I have normal TT's and have the capability to produce high SPL's and excessive amounts of sub-base, if I wish to. Large amounts of mass will decouple vibrations. Mass attenuates LF vibrations the best (see below).

    Way too much common sense! If there were vibrations coming from the wall, I would put a rubber gasket between the TT shelf and the wall.

    I understand that there will be footfall vibrations in an old wooden house, those obviously need to be isolated.

    Decouple from floor, decouple from base, save the sandbox for the kiddies.

    You're not going to change any of the resonances that the plith and the TT components have, from direct vibration.

    I do not have the same issues that many others have, because I have a solid concrete foundation and ceramic tile floors. I have two heavy bases the are not subject to randomly induced vibrations.

    The cabinet on the right is made of MDF and is heavy. MDF has multiple small resonant frequencies to there is never one dominant frequency, which is why it is used for speaker cabinet construction. The other reason is that it can be easily shaped and is cheap. The TT sitting on top is a Vinyl Nirvana vintage, restored and upgraded, Thorens TD-160 Super, which is a suspended TT on a custom heavy solid wood plith. No vibration issues.

    [​IMG]

    The TT on the left is a Rega RP6 sitting on top of a massive custom Klipsch La Scala. It happens to be decoupled fom the floor by a large piece of cardboard that I use to slide it around. On the top is a piece of glass which is isolated by clear silicone disks. On top of that is a Rega RP6, with Rega's standard feet.

    In each case, I am using only the standard feet that came standard on the TT, assuming that the manufacturer had some sort of an idea how to isolate their TT's in the first place.

    On the other side of the curtain is another La Scalla and directly behind it, is the largest Polk Audio sub that they make, a DSW PRO 660, which is the rear sub. It is in a large cabinet with a downward firing 12" sub-bass driver which plays down to 25-Hz. at its -3 dB point, and is powered by a 400-Watt plate amplifier.

    In front and pointed towards the TT's are two large Altec Lansing A7 Voice of the Theater speakers, powered by various tube amplification. The left cabinet is shown.

    [​IMG]

    In addition, to the left of the A7, there is a large passive 15" horn loaded commercial sub, powered by a Crown XTi-2000, in bridged mono mode, which can deliver 1,600-Watts to the sub. The sub us a Yorkville UCS-1, which can sustain a SPL of 133-dB continuous program material.

    I don't have any vibration issues with the TT's what so ever that can be heard.

    Isolating a TT is not rocket science, even though it appears that it is.

    On top of all this, there are two pairs front main towers. A Zu Audio, Omen Definition's and a pair of Polk Audio's flagship LSiM707's, which have large bass drivers, have downward firing ports and weigh in at 99-lbs. each.

    [​IMG]
     
    Last edited: Sep 27, 2018
  3. Pastafarian

    Pastafarian Forum Resident

    I'm surprised that you think there's no energy in your wall, a neighbor would be able to confirm there's enough to move the air in their room.

    Your flooring is one of the worst for a HI-FI system, give me wood, concrete won't stop the bass and ceramic tiles sound like a good high frequency skin.

    You say no problems with vibration but I can't understand on what basis you believe you have no issues.
     
    Ontheone likes this.
  4. SandAndGlass

    SandAndGlass Twilight Forum Resident

    Let's start with this one.

    I don't agree with your statements at all.

    First off, you seem to be grossly misquoting me. Suggest you READ my posts and make a better effort to understand what was actually said.

    About every poster in the thread has recommended a wall mount for the OP's TT. as the first and best solution to decouple the TT from the floor and footfall and other vibrations.

    I went on to say was,

    The meaning of this is, that if there is a further need to decouple the wall bracket from the wall, a rubber spacer could be put between the wall mount and the wall.

    If there were still issues, a spacer could be put between the wall creating a second more isolated wall of which to mount the TT rack.

    In the event that you have might have missed posts from these other poster's.

    It appears that our other members are recommending a wall mount in order to minimize vibration from the floor.

    Member Guth, has double mounted his wall bracket, similar to what I would suggest, for extra isolation.

    Guth has also pointed out that Rega, being the manufacture of the TT has recommended this way as the most effective way to isolate the TT.

    Your position seem to disagree both with the wisdom and experience of our other members but the manufacturer as well.

    Footfalls and most other floor related vibrations are low frequency vibrations, so I will continue to limit my comments to those LF vibrations.

    You are incorrect, way incorrect!

    LF sound is energy. If you want to move an object, it will take more energy to move a heavy object than a light object. That is not only physics but it also common sense!

    Now, you can decouple an object by placing a light weight material such as a foam between one object and another to decouple it, because the LF sound vibrations will pass through the foam, without transmitting excessive vibrations. Which is why, if you want to isolate bass from one room to another, you do not use foam as your first choice, you use a heavy solid concrete barrier.

    The more mass (weight) that an object has, the more energy it will take to vibrate it. While a solid concrete floor can transmit sound, it will also quickly attenuate it.

    This a photo of the listening room from outside of the building. The room is surrounded by concrete. The windows are double windows for hurricane protection. In addition, there are plywood sheets over over the glass windows for extra protection. The sundeck is concrete, which is the roof over the listening room.

    [​IMG]

    What basis I have that I don't have any "audible" vibration issues, is that I can play loud sub-bass heavy music like Debstep and also play "earthquakes" loudly through the HT's LFE channel through the huge commercial sub in one of my photos with a 1,600-Watt class "D" amp and neither of my turntable's will produce any audible vibration.

    All of the speakers in the shown in the photos are isolated from the floor and the amount of direct vibrations to the floor are therefore minimized. Although the bass cabinets in the Altec Lansing A7's don't play deep (which is why the sub is in play), they do play some very strong bass.

    The floor is hard ceramic tile over a concrete foundation, which is about as effective in minimizing vibrations as you can get. The floor is the foundation of the building and will transmit some LF sounds, but not very low frequency vibrations which can be felt. The concrete foundation weighs tons and does not vibrate in any form that can be felt by resting you bare feet on it.

    Since I hear no issues, I have no issues. If I need a seismograph in order to measure vibrations that I can't physically sense or do not audibly disturb a record that may be playing, then I have no issues, and I can produce some serious bass and sub-bass.
     
  5. Pastafarian

    Pastafarian Forum Resident

    I didn't suggest wall mounting may not be the best solution for you or others, given your floor it could well be for you but people shouldn't believe that mechanical energy is side-stepped by a wall. I'd be surprised if spacers are going to be much of a barrier to all that energy you must be generating

    My experience when I had a Rega and then a LP12, low mass table is the best, mine weighed about 1 Kilo, energy migrates to high mass and it'd need to be very high mass to stop it. As for vibration being a problem unless it's footfall you'd only know if the vibration is reduced.

    I'm not saying your system doesn't sounds great but it may have more potential
     
    SandAndGlass likes this.
  6. karma67

    karma67 Forum Resident

    Location:
    uk
    i found using 2 shelves under my turntable with plasticine between the shelves works very well and is simple and cheap
     
  7. SandAndGlass

    SandAndGlass Twilight Forum Resident

    Naturally any surface can transmit energy. I live in Florida and don't have the same issues that people have in older multi-story wooden homes. For those, wall mounting or suspended, hanging from the ceiling may be their best and most cost effective options. I have never had the need to mount a TT on a wall, in my environments.

    At least member's having private homes, don't have to worry like someone in an apartment, with a wall mounted TT and having someone direct next door with rear firing subs! :)

    The place that I am was built back in the late 1960's and is built like the proverbial brick S.H. It is somewhat amazing how this room contains sound. I am the owner/operator of a small motel on the beach area and my listening room was the former lobby of the motel.

    Although I can generate an almost limitless amount of sound energy in this room, I generally listen to things at lower volume levels and have evolved the system to sound rich and fuller than the louder SPL's I used to generate some years back. One, I do place some value on my hearing. Two, my ears are aging like the rest of me and they no longer crave the dynamics that I used to generate in years past.

    My mind sill craves the dynamics, but my ears say no, no, no! So the "ears" have the final say. But that's OK, just another stop on my audio journey. But, when I get things sounding as well as I do, then I would have to say that I am completely happy with what I have achieved.

    You are right, there is always more potential. I would love to have a sub system with a pair of 18" drivers, for the really deep stuff. Unfortunately my back door opens up into the patio and swimming pool deck of the motel, with the guest rooms surrounding it. The wall is a combination of solid concrete but some time ago, part of it had been closed in with some framed lumber and sheet rock and, not being solid concrete, there is a limit on how much sub-bass that I can block.

    There are always more ideas that I have yet to realize, but I have come very far to make the majority of these ideas a reality.

    If you have some time, I have added an illustrated system tour to the bottom of my system profile. It will provide better insight into the listening room.

    Cheer's

    S&G
     
  8. Pastafarian

    Pastafarian Forum Resident

    I've looked at your profile page and I presume I'm wrong but your Rega seems to be on top of a speaker. From playing around in various locations isolating your speaker from the floor makes a major difference in how much you excite the building and how reducing input to your electronics can transform the music.

    I've moved several times and all properties have been Victorian terraced properties with suspended wooden floors apart from my present concrete floored music room.

    I often play bass heavy music loud and I've heard how loud it can be next door but the first time I isolated my RELL sub the difference next door was amazing, my music didn't sound much louder than their TV in our house.

    Now on the concrete floor and finding out how much my electronic were being adversely affected after I isolated my speakers was a big surprise even though I'd used the same method before on wooden flooring.

    As I no longer have much disposable income I've had to approach it on the cheap, so my RELL sub is on a old IKEA shelf on two inner tubes. My RELL weighs 60 Kilos and this DIY method means having to inflate the inner tubes after about 6 months, this means me doing it alone but the effort is well worth it, in fact you're forced to when you begin to hear the sound degrade. To me it seems pretty obvious address the energy at it's source, it's surprising you'd think it would be the sound waves causing all the problems
     
    SandAndGlass likes this.
  9. SandAndGlass

    SandAndGlass Twilight Forum Resident

    I'm all for DIY solutions. Inner tubes work as well and better than any "audiophile" solution and it a lot less expensive!

    I did a lot of accelerated buying, because I decided to do it while I could afford the cash outlay. Plus, being a senior citizen, I also decided to do it while I could. :cool:

    One of the TT's are definitely sitting on top of one of the heavy Klipsch La Scala's.

    But, they have been out of the system since 2014. They have to sit somewhere, better be there. The other cabinet is on the other side of the front door, where it also serves to place my groceries when I am bringing them in from the car.

    [​IMG]
     
    Pastafarian likes this.
  10. Pastafarian

    Pastafarian Forum Resident

    I don't know which impresses me the most, your system or the fact you listen to Dubstep (at your age).
     
    Bananas&blow and SandAndGlass like this.
  11. SandAndGlass

    SandAndGlass Twilight Forum Resident

    I view Dubstep as a style, more than I am familiar with Dubstep specific artists. I view Dubstep as intelligent bass.

    In the "colonies", we seem to have gotten away from artful ways of presenting bass in music, electing for the Boom, Boom, Boom sound. AWFUL!

    But my age? :) I hail from the Rock music and Rock concert's generation. I had my original pair of A7's custom built back when I was sixteen and still in H.S.. At the time that they were being built, I didn't even own an amp to drive them yet.

    That would have been back in about 1970. The actual A7 was a new product of Altec Lansing, only a few years old at the time. The A7 was designed to provide the same quality of their larger Theater cabinet designs, like the A4's, but was designed so that it could also be used for portable use and was specified for small venues for up to 800 people.

    Back then, just about everyone was building various P.A. cabinets. Mostly local P.A. companies, with their own cabinet designs were hired to provide the sound reinforcement for Rock concerts. Sometimes, I noted that there were professionally designed cabinets that sounded excellent, but most of the local "amateur" stuff was crap.

    In as much as I was a teenager, who listened to Rock music, I was not inspired by typical home stereo speakers that most people were buying at the time. What I wanted was a pair of speakers that I could use for anything. Why not? I could play my stereo through it, have live vocal's, plug in a guitar, basically do what ever I wanted to do. The A7 was the answer.

    In the ensuing years, Rock faded away, Saturday Night Fever came on the scene and rock oriented night clubs were being replaced by disco's. Now the A7's could handle everything that Rock music could throw at it. But when disco clubs appeared on the scene, music was different, more full range with deeper bass and higher highs. Earlier club sound systems couldn't quite cut the mustard. But as the demand for bigger and better clubs emerged, the sound systems for these clubs were vastly improved. By this, I mean they were exponentially better.

    There was some serious, kick you in the chest type of deep base and take the top of your head off high's. Back then, in the late 70's and early eighties, club DJ's used only TT's as CD's were not yet in the scene. Direct drive turntables were the DJ standard, so that the DJ's could que up music and segue from one EP 45 to the next. TT isolation techniques were developed and they were surprisingly effective against the brutal bass of Disco, played loud.

    Two-way systems could no longer handle the demands. Faithful Disco reproduction required huge bass cabinets and HF super-tweeters. I began to rethink what the A7's were lacking...

    Fast forward to present day.

    The A7's are now a four way system with a commercial sub and super tweeters. The sub is set to 40-Hz. and below and is used both for stereo and HT LFE.

    In stereo, you don't even realize that it is in the system, until it is called upon to do it's thing. I have a favorite movie that I use to demonstrate effective deep bass with earth splitting special effects. This is my favorite, unconventional "Dubstep" version of an original piece by artist Lindsey Stirling, who plays the violin. I like this piece because, since she plays the violin while she dances in the video, there is hardly any significant LF information until the bass and sub-bass "Dubstep" parts come in.

    Here is Lindsey Stirling with her YouTube Dubstep version of Crystallize.



    This is a good test piece to check TT isolation because there are places where the bass and sub-bass is and where it is not.

    Those with a subwoofer(s) in their system should play this without a sub in the system and again with the sub out of the system. It is excellent to check your sub integration and your TT isolation.

    Bass and sub-bass rules! But, it needs to be done right!
     
  12. dougotte

    dougotte Petty, Annoying Dilettante

    Location:
    Washington, DC
    I bought this a year or two ago, but didn't give it a fair shot and got rid of it quickly. Reading your post, I thought I'd try it again.

    First, my setup is in the basement with a cement floor covered by some throw rugs. I don't have any problem w/ footfalls etc. However, the turntable is in a corner alcove, and I'd been thinking some resonances are probably echoing around in there and getting to the stylus. It doesn't sound muddy, but there is a slight degradation.

    I tested like this:
    1) Put the stylus down on a still LP.
    2) Rap knuckle on the shelf.
    3) I hear thumps through the speakers.

    When I try the same thing w/ the Auralex, there is no difference! So, maybe it doesn't help with airborne resonances; I don't know. I'll play some discs to listen for any improvement in sound. What do you think?
     
  13. Davey

    Davey NP: Portishead ~ Portishead (1997)

    Location:
    SF Bay Area, USA
    Maybe I don't understand your test, but why do you equate rapping your knuckle on the shelf with airborne resonances? Isn't the shelf part of the structure the table sits on? I doubt the Auralex will do much for attenuating low frequencies, it's just a piece of MDF and some stiff foam, right? Seems like it's designed for reducing higher frequency vibrations from the support structure to your table.
     
  14. dougotte

    dougotte Petty, Annoying Dilettante

    Location:
    Washington, DC
    I just tested it by listening carefully to a bass-heavy track, both with and without the Auralex. I couldn't hear any different in any frequency range, transients, or soundstage. I'm leaning toward returning it, but I'll try it again for a week or so.
     
  15. dougotte

    dougotte Petty, Annoying Dilettante

    Location:
    Washington, DC
    You're right about me mixing up shelf and airborne resonances. That was faulty thinking on my part (won't be the first or last time!).
     
  16. Pastafarian

    Pastafarian Forum Resident

    My take on it that the Auralex is a barrier to mechanical energy, so if anything it's going to make energy in the deck stay there. It's function is primarily to stop ground borne energy entering your deck.
     
  17. JOnny Cox

    JOnny Cox Forum Resident

    Location:
    Bridgend
    I have my Rega RP3 on the IKEA bamboo board and cork dots between the board and my oak furniture. I know the idea is to then couple the turntable to the bamboo to drain vibrations into the bamboo. My concern is I have the Tangospinner feet which I’ve read are isolators! So would i be better off removing these and replacing with oak coned feet for example?
     
  18. Pastafarian

    Pastafarian Forum Resident

    My take on this is very different, as it's about reducing energy going in to your Rega rather than using Bamboo to drain energy from the deck.

    Presuming the Tangospinner feet are better at isolating I'd stick with them, one method to drain energy from the deck are roller balls devices.
     
  19. Guth

    Guth Music Lover

    Location:
    Oregon
    Regarding my turntable wall bracket installation, I would note that had the holes in the turntable wall bracket aligned with with the studs in the wall, I likely would have just mounted the bracket directly to the wall/studs. But since that wasn't the case, I used the piece of oak board so that I could screw the board directly into the studs and then screw the bracket into the oak board. In theory making this both a more solid and more secure connection rather than using something like mollys or toggle bolts, neither of which appealed to me as the best way to go about things. The fact that I liked the way everything looked when finished was a bonus.

    I've messed around with this kind of thing with various turntables in the past. As far as all the various isolation or coupling theories go, like with most things audio related I experimented and trusted my own ears. Since my speakers are of a ported/vented design I could also literally view the difference proper placement made just by watching the woofer cones. It used to be that all but the cheapest receivers included a switchable subsonic filter. Back in the day people placed their turntables just about anywhere making them more susceptible to a variety of vibrations plus many of those turntables inherently had quite a bit of rumble, both resulting in lots of wasted energy as speakers tried to reproduce what they were being fed. Just like a properly placed turntable today (whether you are going for isolation or coupling) the subsonic filter negated most of undesirable impacts (I still have that option available to me in my vintage system down in the basement). The effect was much the same although there is no doubt some kind of sonic tradeoff being made by introducing the filter into the signal path. I suppose it's better to cut out all of the unwanted impacts sooner with the turntable setup/placement rather than later with the filter. Of course headphones would take care of the airborne vibrations as already mentioned, but things like structural vibrations and rumble are another matter.
     
    SandAndGlass likes this.
  20. eflatminor

    eflatminor Forum Resident

    Location:
    Nevada
    I did the same thing, only I used marine plywood instead of oak as I was planning on a very heavy turntable at the time (never materialized). That said, I'm sure I could stand on my wall shelf and it wouldn't budge...and I'm not exactly petite!
     
  21. Guth

    Guth Music Lover

    Location:
    Oregon
    Interesting solution. While the Rega wall bracket is incredibly stiff it’s also quite light (much like their turntables). While it feels impressively sturdy once mounted, it was engineered with this one specific task in mind. I have no idea how much weight it would actually hold. Thinking about this reminds me of my Statics coursework back in engineering school. While the actual weight that it could support would likely surprise most folks, I have no concerns that the oak board combined with the specific screws I used are more than up to the task. I do like the thought of marine plywood, I used the oak simply because I had some scrap pieces laying around. It was a bit of a shame to paint over the oak but it’s served it’s purpose quite well.

    As one more point of reference (I have no idea whether or not this helps me or works against me), the wall my bracket is mounted to is a load bearing wall.
     
    Last edited: Jan 19, 2019
  22. Gibsonian

    Gibsonian Forum Resident

    Location:
    Iowa, USA
    Isolate for sure. Couple to nearly immovable objects, isolate from the rest.
     
    plastico likes this.
  23. McGuy

    McGuy All Mc, all the time...

    Location:
    Chicago
    I was in the same boat, posted the same questions on various boards and got way too many answers! it got confusing after awhile. So I just ended up sucking it up and getting the pro-ject isolation table - and I have a VPI Prime Scout for reference. I love this isolation table! wasn't cheap but it was under $300 off ebay, think close to $225. and the guy I bought it from included the Herbie's feet with it. so, sort of double isolation, triple if you count the amazing VPI feet that come on the table itself.
     
  24. KT88

    KT88 Senior Member

    Only one way to find out.
    -Bill
     
  25. BKphoto

    BKphoto JazzAllDay

    Mine is both,

    TT is coupled to a maple butcher block by using spikes

    Butcher block is isolated by using vibrapods
     
Thread Status:
Not open for further replies.

Share This Page

molar-endocrine