VPI TNT Mk 3 – Looking for a tonearm and cartridge


Greetings analog lovers!

After a long hiatus I have been getting back into vinyl and have been reading like a madman. I’d like to get a new tonearm and cartridge but before I start cutting checks I’d like to tap into the immense reserve of analog knowledge here. Amazing what you can learn here!

Here is a link to my system so you have a better idea of what I’m working with.

https://systems.audiogon.com/systems/7076

Turntable:

VPI TNT MK 3 – solid acrylic plinth with arm board, stainless steel towers with internal springs - elephant feet, Hurst 600RPM motor, tri-pulley with capstan pulleys at 1:00 and 5:00 used and VPI rubber belt.

Mk 5 platter which has a Rulon main bushing. A combination of 50% Delrin and 50% non-magnetic stainless steel and weighs in at 21lbs.

Mk5 Bearing and Spindle - The limited release bearing. Unlike the rest of the TNT bearings, the Mk5 bearing is made out of non-magnetic stainless steel (not aluminum) and is attached to the plinth via a large stainless steel threaded donut.

Tonearm:

Modified Rega RB300, re-wired with one piece Incognito Cardas copper rewire kit, VPI VTA adjuster for Rega tonearm, TWL lead weights glued onto gimbal bolts, it looks crazy but it made a massive difference in sound quality. Expressimo Audio – The Heavy Weight on the end stub.

Cartridge:

Benz Micro Lo.4, VTF at 1.9grams. Output - .44mV

Turntable Table:

Solid maple table with spikes into wool carpeting, floor. Takes two people to move this thing.

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That’s a pretty good description of the turntable. Here’s what I’ve thought about doing to address some of the weaknesses.

To Do:

Remove tri-pulley system and drive platter directly from the motor.

Motor controller – maybe SDS, wish I could buy the Phoenix Eagle/RoadRunner.  Might do a motor and controller that’s available on a DIY website that’s supposed to be pretty good.

Table suspension:  I’m not into the air suspension camp – so not feeling that….

I really like the VPI Avenger Reference feet, maybe possible to retrofit them into the corner pods. I think that would be a beautiful option.

Maybe StillPoints but these are serious money - http://www.stillpoints.us/index.php/product

Maybe brass Bearpaws - http://edensoundaudio.com/shop/category/bearpaw-brass-footers

I guess I’m up in the air on table suspension, I can’t say I’ve had trouble with the springs…they seem to do their job and I don’t hear/notice a problem….but I might hear a change for the better if I did one….

I have really enjoyed the Benz Micro Lo.4 – it has a wonderful sound but I’ve also never had another top flight (to me) cartridge mounted on the Rega so what do I know. I’m leaning towards a Benz Micro LP-S. By all who have owned or listened to it they describe it as 1st rate. It does weigh 16.4 grams, .33mV output – but with the SUT I have going into my CAT SL1 Signature MK 3 preamp I’m thinking I should be OK.

So….I have a conundrum. To change the Rega arm I need to get another arm board which VPI doesn’t make anymore. I’ve been told to find an acrylic shop or even make one out of wood but I have no technical drawings and no idea where to go other than hell.

I live in Minneapolis, MN – home of allot of high tech stuff but no names or contacts. No relationships with dealers either although that’s easily remedied.

If I did get an arm board made I still need a hole drilled in the exact location for the particular arm that ends of being the chosen one.  And just to confuse the situation I don’t think I can use my current arm board – even for a Rega mount drop in because I have the VPI VTA adjuster installed which may or may not be a problem with the new arm. I do know the hole is bigger than a normal Rega tonearm but I don’t have its size without taking it apart to measure.

I suppose I could just get the Benz Micro LP-S and mount it on my modified Rega and call it a day but well, you know….what’s the fun in that?!

Plus, it might not be a good synergistic match between the two and we all know how important that is!

Of course one of the most important considerations is how big a stack of Benjamin’s to play with?

Here’s my philosophy on that – I really love buying fabulous used that has a great track record. Sometimes you can’t – I bought my Berning amp new because that was the only way to get one. But most things you can. In this case I’ll be buying the cartridge new. Maybe even the tonearm but maybe not. So here’s my budget which is fairly flexible.

Cartridge: $5K

Motor/controller: $1K

Suspension if done: $1K-$3K (this may not be done – I’m still undecided)

Tonearm: I’d really like to stay below $10K but I’d like to have some room for ideas here.

I have a few thoughts but not wedded to them – but from reading and my electrical background here are my ideas:

I’d like it to have a continuous run of wire from RCA connectors to head shell pins.

I do like the idea of being able to change head shells or tonearms for different cartridges but if I do go the route of Benz Micro LP-S cartridge I’m probably going to be more than happy to stick with that. But, it is nice to have the choice to change if so desired.

Unipivot or gimbal camp – no air bearing arms. I actually would have gotten the Trans-Fi Terminator but he closed up shop. Sigh…

Probably not wood tonearm.

I think I’d really love a Basis Audio - Superarm nine tonearm (duh) but it’s almost $16K and well, that is allot of money for a tonearm)

Sorry for the long post but I thought I’d include enough context and background info to help you with your ideas….

 

Thanks for any help/direction you can provide!

Regards,

Brian


128x128mr_slate
Melm, VPI TT of the era could be outfitted with speed controllers, I just don’t happen to have one....... yet. Shame me enough and I will probably relent ;) .

From what info I have been able to gather up, the Mk IV platter was an upgrade option for the TNT Mk 3/4 turntables. Prior platter options were an all acrylic, a lead lined acrylic and then the Mk IV which was an aluminum/delrin/cork sandwich which was also lead lined. 11.5" in diameter and only 1.25" thick, the delrin layer is about 1/4" thick with the 1" aluminum. It weighs about 15 lbs compared to the 8 lb acrylic but was far short of the 25 lb Superplatter and the 22 lb Classic. It has the 1.25" normal oil bath bearing vs the inverted bearing my acrylic platter had. It also has the three leveling screws in the bearing plate that aid in setting precise runout on the platter and to help isolate the platter from bearing/plinth vibrations. Downside is the diameter and the fact that the periphery ring weights cannot be used. The stigma of having lead as part of the system probably killed the Mk IV and the Mk V emerged as a half stainless steel, half delrin platter.

You are correct on the Classic platter debate...It is supposed to be very detailed but it is not to everyone’s liking and seems on some systems to be a bit too bright. I am running the TNT to Amazon B-Lab phono, Tom Evans Vibe pre, Lamm ML 2.1 mono blocks to Avantgarde Duo Grosso speakers...those in the know think that the Classic platter would be my best option for my setup but sticking with the Mk IV for now.
"Shame me enough and I will probably relent ;)"  Well, I'll do my best.

I have an original TNT with the lead lined acrylic platter.  Wouldn't change that for anything.  I have faith in the non-inverted bearings; mine is a Mark V.

A couple of years ago I scored a 2.5 lb TTWeights peripheral weight and would not be without it.  .There is a guy making similar rings advertising on Audiogon.  Even though my platter is also 11.5", I considered the VPI ring.  I believe it can be adapted for the smaller platter by lining it with felt.  I thought of using felt with an adhesive layer intended for door insulation.  If I hadn't discovered the ring I have, would have done that. 

Happy listening.
Interesting.... what type of back end are you running tube or SS? And what is the weight of your lead lined acrylic platter? Platter thickness?

I agree on the bearing...I am not sure I have been convinced that the inverted is a better set up, Some have said that having the platter "hanging" from the platter level is better from a mechanical engineering standpoint. I prefer the knowledge that the non-inverted is always lubricated and that the leveling screws help isolate the platter from bearing and plinth vibration. However, I have seen people who recommend backing the screws off, thus defeating the whole purpose. I guess they get frustrated with the leveling process and are bound to blame the platter sound instead.
The platter is 20 lbs and 1 3/8" thick. It’s not actually lead 'lined". That connotes something thin. The lead is a thick slab of metal forming a flat ring underneath the platter.  The ring weight, by the way, extends well past the platter perimeter and adds to the flywheel effect.

I use a three stage all tube unit, the Fosgate Signature. The rest of the system is SS.
Good question on the room - acoustics play a huge part in the sonic picture. My room is not very big - 16'x14' - so I needed to tame the poor frequency response. I bought several bass traps, they're actually called Realtraps - http://realtraps.com/
The owner - Ethan Winer has some very good research and analysis papers with thoughtful ways to correct room nodes and treat the room properly. Makes a huge difference in sound quality.

If you look at my system you'll see a few photos of them. The big ones are hanging in the corners, front and rear walls have normal size - both LF and HF type and the side mirror points have HF type.

Update on equipment:TNT is in pieces - measuring for an arm board which I'd like to make out of wood. Need to visit a place here in town that supposedly has exotic wood from all over the world.

Chose a new tonearm - 12" Reed 3P to go with a Grado Statement v2 cartridge. That will be a whole new sound to me!

Need to do something about a speed controller. In the past I've adjusted the platter speed  by changing the tension on the belt by moving the motor closer or further away from the platter. Not very elegant but it worked.

Going to try surgical thread or silk thread for a drive belt. Micro-Seiki has some thread K5 - they must think it's spun gold for what they want for it.