don't tap on the cabinet.
Your setup is fine. You didn't notice this UNTIL you tapped on the cabinet. Audio neurosis.
Your setup is fine. You didn't notice this UNTIL you tapped on the cabinet. Audio neurosis.
Tapping on my table
Searched some threads and did not find an answer specific to my question, so I will try here. My system is in my basement, which is a concrete slab with wall to wall carpet ( and carpet pad). My TT is a Music Hall MMF 9.1 which has 3 plinths separated by sorbothane spacers. The TT sits via its conical feet directly on a Salamander cabinet holding my amp and cd player plus some albums. Total weight of the cabinet, equipment and albums is at least 150 lbs. The TT weighs 40 lbs.
I have never experienced any issues with vibration, i.e when walking around while playing an lp. I had assumed the concrete floor and thick carpet, along with the heft of the cabinet and contents, provided excellent isolation. However, this morning I inadvertently tapped the top of the cabinet while listening to an album and there was a very subtle but distinct thump emanating from the speaker. Clearly the TT is not isolated from the cabinet even if the cabinet is isolating the TT from the floor.
Is there a good inexpensive solution to solve this isolation issue? I do not want to lose the leveling benefit of the TT's feet - I have some Herbies cones under my cd player, but these would eliminate the leveling capability.
I have never experienced any issues with vibration, i.e when walking around while playing an lp. I had assumed the concrete floor and thick carpet, along with the heft of the cabinet and contents, provided excellent isolation. However, this morning I inadvertently tapped the top of the cabinet while listening to an album and there was a very subtle but distinct thump emanating from the speaker. Clearly the TT is not isolated from the cabinet even if the cabinet is isolating the TT from the floor.
Is there a good inexpensive solution to solve this isolation issue? I do not want to lose the leveling benefit of the TT's feet - I have some Herbies cones under my cd player, but these would eliminate the leveling capability.
21 responses Add your response
How far is your turntable from your speakers? Is it possible that audio from your speakers could reach your turntable and cause vibration in the cabinet, which the turntable could pick up as it did your finger tap? If so, that could cause a blurring to your sound. If the turntable is distant from your speakers, there's probably no problem. |
If footfalls bounce the arm around (impossible except for a nuclear attack or similar... with a concrete floor) you're fine for that frequency. You're hearing things from your cabinet, because of the higher frequency. My table is also on concrete, but got additional isolation by installing BearPaws which surely improved the mids/highs because they lessened those frequencies. In truth, you can't damp everything effectively, but it pays to play with gizmos to "tune" your system to work as well as you can make it work. |
Patient : "Doctor - it hurts when I do this". Doctor: "Then don't do that." ( Henny Youngman) What are BearPaws? Thought I might steal my wife's marble pastry board and put 3 vibrapods underneath and put the TT on top. Thoughts? "When I read about the evils of drinking, I gave up reading." (Henny Youngman) |
I use this http://www.crutchfield.com/p_927ISOTONE/Auralex-ISO-Tone.html?tp=68326&awkw=134193792265&awa... Inexpensive and it works Alan |
The Townshend Audio Seismic Pods and/or Platform deal with exactly your problem sjtm. Watch the You Tube video in which Max describes and explains their design, and then demonstrates their effectiveness at providing isolation. Three or four of the pods under your table will provide a very high degree of isolation from your cabinet. |
raymonda Magnetic feet, airblatter systems, vibraplane or what I use......a home made sand box with about 75lbs of sand. The last option is fairly inexpensive. e.g. less than $50.00. You don’t see sandboxes much these days but they were ubiquitous 25-30 years ago. Good on ya, mate. Bright Star, who later went on to make air bladder stands, made sandboxes for placing on the top of components, too, as well as underneath. I’m high on sandboxes, too, especially when substituting perfectly round pure glass microspheres for the sand, which is kind of gnarly by contrast. |
The Bright Star sand box was named Big Rock, and came in many different sizes. I found silica "sand" at a building supply yard for eight bucks for a hundred pound bag. Silica is a non-organic man made product similar to sand, used for sand blasting, etc., and comes in many different grades (size of the granules). I used Grade 60, which is granules of very small size. Their very small size allows more granules to fit in a cubic inch, thereby providing more absorption and dissipation of vibration. Anything higher in grade that 60 was almost a powder. The "sandboxes" Bright Star made for placing on top of components (to damp chassis resonances and vibrations) were named Little Rock, also offered in various sizes. They actually were filled with some kind of granules (neither sand nor silica) that provided not only damping, but also magnetic shielding. |
sjtm from my past experiences, the key imo is you want to turn your cartridge/system into a type of stethoscope for your room. Also poured concrete slabs are far from perfect containing air pockets. Your rig could be on one of them. How to find out ? sjtm There is an inexpensive way and it can be kind of fun too. With system on mute and set to the lowest volume. Place record on the platter - not spinning - and lower your stylus onto it. Unmute and slowly start raising volume to what represents a loud level for you. Your cartridge/system has now become a stethoscope to your room. So ....standing near the stand, start jumping up and down .......like you have won the lottery. (waving arms optional) Dance in front of, beside, and behind it if possible. Is anything heard through the speakers when you do this ? If yes your turntable stand is not on good ground. Move to another spot. Good luck. |
There are two issues here, IMO. First is the stability of the cabinet, which is a function of construction, TT mass, and the ratio of the height to the smaller of depth and width. The second is sinking transients to ground. The solution which I found, because my 150 lb TT dictated it, was to lengthen the width of my cabinet to 40 feet, by the simple expedient of bolting it to the frame of the house. This also served to sink transients to the frame and thence to the concrete foundation. Problem solved. Of course, the wife doesn't yet know there are holes in the Louis XIV desk ... |
Hi Dustin let’s think about this. Does it make sense to try this technique on an unsuspended turntable setup, that is directly coupled to suspended springy wood beam floors ? imo, no. why bother? Btw - how many Audio Boutiques have you been to where they are using a beautiful historic Brick and Mortar house, and have a turntable set up on the 2nd floor - wood floors ? So a stable setup to begin with is needed. There is always a higher risk with vinyl just by the physics nature of it. The horizontal platter/lp acting like a possible angle grinder on the vertical cantilever, especially on well endowed cartridges, comes to mind. To help with any worries keep the turntable unplugged, and ensure your phono stage and amp are good quality and electronically stable. btw I have learned some good can also come from this exercise, if your wife catches you doing "this dance" in silence. She might think you have maybe just "lost it", ....gone over the top. So you may gain back some leverage. If you choose to do the dance without the option of waving your hands around; she may also think you are auditioning for Riverdance. https://www.youtube.com/watch?v=HgGAzBDE454 :^) Cheers Chris |
Yes just don’t tap on the cabinet. If you are determined to have a more robust stand/platform for your table it need not be expensive. My room is similar to yours including floor and my table sets on a very heavy and massive 15" tall antique solid oak coffee table (constructed from 1 inch + thick oak wood slabs) I found in a used furniture shop down south many years ago for $30. It provides a rock solid foundation for the table and the other gear (pre-amp and DAC) that sets on it so no worries ever. You can tap away and never hear a thing. |
