I have discovered that the source makes or breaks the system, therefore I put some time into improving the turntable. It started off when I made my own platters out of acrylic and within the platter made cylindrical encasements to hold leadshot. I also replaced the feet with my custom made acrylic tubes again filled with leadshot. I kept using acrylic and leadshot for the tonearm board support and the bearing holding structure to avoid drilling out the original plinth since I was installing the latest vpi hr-x platter weighing in at 33 pounds or thereabouts and the bearing is much wider in diameter than the original bearing. Each time I made an improvement the source became quieter and so much more was coming out. Very happy to say the least. Also need to point out that the turntable is swinging off steel cables, so I like to think of it as the tt being somewhat decoupled from the room. There are some bungie chords as part of the suspension system for the turntable. The whole thing weighs right around 400 pounds some of it as part of the flywheel assembly. I would say the turntable is about 250 pounds. Also on top of the platter rests a weight also composed of you guessed it acrylic and leadshot, well there was this sale and I couldn't resist. Also using the periphery ring. And on top of the cartridge is oh I hate to say it so I'll let you figure it out. How it sounds is all that counts, so I can say enthusiastically it's beautiful. Not the end all, but it never will be in this crazy hobby, gottta love it!!
Far from what I had purchased 2 years ago used here on gon. It's total weight around 430 pounds with custom flywheel assembly.
VPI Industries TNT-5
Another view of the flywheel (from old tnt model) that needs 4 motors (3 motors shown here from previous setup, added motor since then) to spin the 95 lbs. of rotational mass. An intermediary pulley (old flywheel) is used to transfer rotational force to record loading platter. Cannot find belt long enough to span two platters hence the in between pulley.
VPI Industries TNT-5
An old incarnation of this ongoing project. This picture was taken before leadshot donut was attached to underside of platter.
Flywheel VPI
String driven figure 8 to create better trcation
Flywheel VPI
Stand alone Flywheel
Modification Magnetic Repulsion to platter
Since adding leadshot encased in acrylic to underside of platter I needed to lessen load on bearing with this magnetic repulsion system.
VPI Industries Vpi
With tons of lead shot
VPI Another veiw
Lots of lead shot
Modification to Graham 2.2t
Leadshot stuffed into little canister and straw attached to wand of tonearm.
Denon Denon/zu 103r
103r
K&K Phono stage kit
Awesome, totally awesome. One of the best at this price point, highly recommended!
JLTI Phono
Excellent phono, beats my ear 834p and approaches the K&K phono stage
EAR 834P
Awesome phono stage for the money, should be modified with better caps and tubes!
oppo 980
An out right bargain of a cd/dvd player, highly recommended!!
Sony DVP-S9000es
Nice player.
audio experience a2 se
Very nice preamp for the money, was quite surprised.
Sim Audio Moon P-5
Suspended by bungie chords and loaded with lead shot.
Sim Audio Moon W-5
Awesome ss amp, most highly recommended!
Atma-Sphere ma60 mark II
Lights up the room in more than one way WOW!!
Merlin Music Systems VSM-GEN III RC
Suspended by cables to keep floor from resonating
Merlin Music Systems VSM-GEN III RC
Another view of the suspended system
Martin Logan Depth
Suspended with steel cables from ceiling above full range.
Alesis Masterlink 9600
Cd burner with hard drive to pre-record (to do editting or equalization) before transferring over to cd.
Merlin Bbam, Balanced
Makes the speakers sing as they were designed to with this bbam.
Hi Peter, Good set of points hard won through experience. Having now modified a fair share of components, I would add one more: the gap between an excellent and a superlative component is often in the power supply. A better power supply improves transients, expands the dynamic envelope, and energizes the music like real life. It's suprising how many even very expensive stock components compromise in this area, and how simple it can sometimes be to make improvements.
Hi Peter, are you using both drive systems together, with one drive system pulling the platter with thread, while a separate motor pushes the platter with rim drive? Does this actually sound better than either approach used by itself?
Also, is that the standard VPI fitment that you're using to do the rim drive? I'm unfamiliar with the three-bolt arrangement that fastens your rim drive platter to the flywheel.
Are those many little magnets bored into the plinth and platter, or bonded to the surfaces? If they are thin enough to be bonded to the surfaces, then I might give it a try.
Jean, I see surgical silk 2-0 from various suppliers on the net in 30" lengths. To try this I need at least 55" & would prefer to avoid splicing. Any suggestions as to source?
Also, why do you locate the motor so far away? More thread length = more elasticity. One of the advantages of my idler system is to keep thread spans short. Thanks, Dave
Agreed, my point about optimizing BAM does not address the point source vs. omni discussion. The idea was instead a redirect of Peter's point that "the speaker still sounds like a speaker." BAM is integral to VSM performance across the entire frequency range, as BAM provides(in addition to bass boost) dual-bandpass filters to attenuate both extreme LF and extreme HF. The idea is to eliminate distortions within the audio band that out-of-band content will otherwise induce in the drivers. This is a unique design concept, but as the BAM is an active device with op amps, the outcome is very much dependent on execution. With the older BAMs the result is something of a mixed bag-- the benefits of the BAM offset by a somewhat grainy, flat, and lean op amp sound. But with the latest iteration or some internal mods to power and passive components, transparency & naturalism is much improved.
I've heard big MBLs with MBL electronics, and while impressive in terms of scale, I found them brittle and unnatural sounding-- very much overated. The room was not well treated, however, which could be particularly problematic with omni designs.
Have you seen HW's new rim drive upgrade? If you could find an O-ring large enough to surround a TT platter, you might be able to better the factory set-up by using your second platter as an idler wheel against the primary HRX platter. The HRX platter could then be unweighted and perhaps weight could be added to the idler platter.
Replacing the elastic belt between the two platters with a non-compliant solid coupling should improve speed stability. In addition, HW maintains that a large-diameter idler wheel is much quieter against the platter than a traditional small-diameter, high-speed idler wheel as used in Lencos, Garrards, etc. The new factory rim drive is about half the diameter of a full-sized platter. There might be further reductions in noise at the physical interface going up in diameter and slower in rotation by using a full-sized platter as the rim drive.
You might try tight carpet thread tied with a flyfisherman's blood knot to smooth travel of the knot through the grooves. There should be enough grip.
I may make a tall centerweight as well. I'm tempted to try ebony. I read posters who like the Shun Mook ebony clamp, and am amused that the Shun Mook web site admits that the clamp introduces resonances to the stylus of an additive, euphonic nature. This is not typically what audiophiles strive for, but whatever works... It may be difficult to emulate the Shun Mook resonances, however, as the monks claim to use a rare ebony found only in remote swamp environments. Perhaps a safari is in order.
I'm sure that the heroic mass loading on your TT is successful at resonance control and that the big flywheel has achieved great speed stability. Your TT is so far from any current commercial offering that no-one who has not heard it is qualified to comment.
I was looking once more at your TT set-up and have questions:
Did you ever try using the second flywheel platter connected directly to the primary platter, rather than through the intermediate small VPI flywheel? There are theorists who believe that a full-sized platter makes the best possible flywheel. The effectiveness of the second platter in stabilizing speed might actually be diminished by slop in the belt drive system associated with passing through the small intermediate flywheel.
How heavy is that record clamp? How much benefit does it provide on top of the HRX platter? I am considering making a heavy record clamp for my old TNT black platter, but I am uncertain whether the old-style non-inverted bearing is up to the task.
The improvement in speed stability of low-compliant thread drive relative to VPI elastic belts, is quite audible. But the thread tends to slip-- particularly around the small 600 RPM motor pulley, but evidently also around the 2" flywheel pulley, and also around the platter. The solution is a small freewheel tucked into the pulley on the slack side of the drive system at motor, flywheel, and platter. This obtains close to a 300 degree wrap of thread around the circumference. The idea is similar to the freewheel used by Frank Schroeder in his new tape drive TT. I think that the elasticity of the stock VPI belts is a source of slurring in VPI TTs regardless of drive controller, motor, or flywheel configuration.
I'll post a few pix when I'm done with the pulleys & cantilever for the platter/flywheel segment, but here is a photo of the motor pulley:
Very interesting non-factory updates to the TNT! I'm also working on mine, though from a quite different angle. I'm in process machining more pulleys for the thread drive. What are your belts made from?
