Anyone know any <200 turntables with lots of torque?

[audiosteam]

I found this video today. It illustrates the difference I mention in the previous post. Try to do it with both types of TT and despite the same or higher torque the result won't sound the same
https://youtu.be/lOBG1QODCmo?si=yfxQBvgwRcdOfZIu&t=164

[mushroomjesus]

Cogging and vibrational resonance are factors when picking a table, after extensive weight tests and trial and error with a 1200mk2 I have decided to look into a newer technics vs the OG sp10 still undecided on the sp10r vs GS. I will prob go with gs as it fits my lathe but the 10r would be killer. Maybe overkill. GR2 is brand new but GS is my ideal solution and very different from the G series lineup.

[boryo]

maybe try numark ttx, has lots of torque and older version is cheaper

[farmersplow]

maybe try numark ttx, has lots of torque and older version is cheaper

Additional note: As far as I know, the Numark TT-500 has the same motor as the TTX, but can be found used more often and cheaper. Torque: 4.5 kgf.cm (temporary); 3.5 kgf.cm (stable)

[Dub Studio]

In my albeit very limited experience, torque is certainly not the only factor. Yes you need enough torque… but torque without control is useless.

Direct drive turntable motors come in a variety of flavours, but all of them contain a number of stators (electro magnets, always a multiple of 3) and rotors (permanent magnets, some suitable number depending on the application).

The Technics 1210 has 12 stators (3 x groups of 4) and 16 rotors (although they all form sectors on one permanent magnet).

The stators are switched on and off in a precise order and timing so that the rotors are attracted to them for just long enough that they move the desired distance in the specified time, pulling the platter around as they go.

There is usually a set of hall sensors (one for each phase, so usually 3) that are responsible for switching the correct set of stators on and off as the turntable reaches the correct spot. Which stators are turned on and off, and when, depends on the configuration and number of stators. Hall sensors are used because they can detect proximity without touching (think of them as the brushes on a brushed motor, but instead of making electrical contact, they sense proximity).

Torque then, is just the amount of rotational force that these electromagnets exert on the permanent ones. With most turntables, its a bit more than enough to keep the turntable going steady when a downward force of a few grams is exerted on the outer edge of the platter. You need a bit more because all motors must be overpowered to some degree in order to work… how overpowered a motor is depends on the application. In the case of our turntable, it’s not usually much - just enough to get the turntable going and remain steady after that.

At this point, our brushless DC motor is really not much better than a brushed motor, because there is no decent way to control it’s speed other than to vary the torque by a set amount (by adjusting voltage). The next thing we need is a sensor to detect the speed of the turntable and adjust the torque accordingly.

The hall sensors aren’t really up to this task as the sampling rate is just too low - the Technics 1210 has just 8 points around the shaft that give the hall sensors 16 possible positional readings per revolution, and you need a lot more than that to avoid cogging.

Different turntables have different solutions to this problem, but they are all essentially a form of rotary encoder (some optical, some magnetic) that give off a relatively high-frequency signal that can then be compared against a reference signal. The difference in frequency is used to either reduce or increase the torque (if the frequency coming from the encoder is too low, the torque is increased, if the frequency is too high, the torque is reduced.

This is where things start to get a bit more tricky. In a perfect world, where every disc was perfectly flat, and every platter was smooth and true, the torque really wouldn’t really vary that much. A gradual decrease as the cutting stylus progressed towards the centre of the disc is all that would be needed.

Unfortunately, the world isn’t like that. Discs are not always perfectly smooth, and no turntable is perfectly flat or true. Given that any vertical motion of the cutting surface means more drag on the disc, the torque is in constant need of adjustment. Not to mention that the modulation of the cutting stylus also varies the amount of drag, so we need very precise control of the torque.

Even if we have that precise control, our problems don’t stop there. The amount which the torque must vary needs to be proportional to the frequency variation - too much of an increase and the platter will go too fast and overshoot, too little and the platter will take too long to get back up to speed.

The best way to envisage this is to think of the water temperature in a shower. If the shower suddenly gets too hot, you might be tempted to turn it down a lot, but then a few seconds later the water is too cold, so you turn it up a bit, and so on until you reach the sweet spot… and then someone flushes the toilet and you are back to square one again.

Although we are cutting with around 5 times the normal downward force of the playback stylus (15 grams versus the usual 3 or so), don’t be fooled into thinking that torque needs to be huge. It really doesn’t. It’s the control that matters. You would need an infinite amount of torque for the platter to be unaffected by changes in downward force!

Therefore, I would suggest the best way to assess the suitability of a turntable for cutting (without actually buying it and setting it up) would be to do a simple test: start the turntable, place your finger down gently on the edge of the platter and look at the strobe dots (assuming it has them). Are they still stable? Watch how quickly they return to a stable speed once you lift your finger off the turntable. A Technics will appear to “bounce” from side to side a little, then stabilise quite quickly - obviously the real-world changes in torque will be much less extreme than this, but it’s a good stress test.

Even after passing this test, a turntable could still perform badly for cutting. If I am honest I would be very very surprised if you could find a turntable for under 200 that is any good. You might save money by finding one, but the time you might spend looking for one probably isn’t worth it. My advice: get a Technics 1210 MK2, do the resistor mod, always use the flattest discs you can, and you will be golden.

[Dub Studio]

I came across this old thread and wanted to updated it.

Apparently the torque on the newer Technics SL-1200MK7 can be adjusted rather easily. They also are able to play in reverse not sure how that would apply to this community but worth mentioning. These new decks have the digital pitch control rather than the analog pitch control included in the first iterations of the 1200 models (apparently the analog pitch control is more desirable for more precise beat matching). Also worth noting that Panasonic quietly fixed the pitch control on these newer MK7s because the first batch of turntables were 'inactive' around +-7-8.

https://www.youtube.com/watch?v=8XW-kPkF3IE

I don't have one myself as I'm still rocking a MK2 and MK3D. I prefer the MK3D because there is no middle notch in pitch control so you can really fine tune when you are around +-0.

Before I cam up on a ROK, I was considering getting the MK7 to use with a VR lathe because of this new torque adjustment everyone was going on about. Might be something to research and consider still.

Of course as other vets on here have mentioned, go to piaptk's lathe camp, see if this is something you really want to get into, get a lathe, practice and see where to go next.

Apparently the MK7 is not a good candidate. I like the idea of coreless stators, which should in theory make the motor quieter, but unfortunately because Technics have opted to "eliminated the root cause of cogging" by removing the cores, they no longer need all the great cirtuitry that made the 1210 so stable for cutting. I will unpack that in a later post.

[A1-Voodoo]

@Dub Studio - Besides the MK2 with the resistor mod to get up to 2kg, what do you think about the Technics SP-15 with 3kg starting torque for use with a VR and the precision platter? I'm researching all the available options on there and was thinking that would be a decent torque vs money unit...? Sure everyone wants an SP-10MK3 and all... but that price!

To the OP, the SP-15 does not hit the price point your looking for (more expensive) - apologies for thread jacking momentarily.

[Dub Studio]

maybe try numark ttx, has lots of torque and older version is cheaper

Additional note: As far as I know, the Numark TT-500 has the same motor as the TTX, but can be found used more often and cheaper. Torque: 4.5 kgf.cm (temporary); 3.5 kgf.cm (stable)

Unfortunately, the torque of a motor (published or even measured) cannot be used as a proxy for cutting suitability. I learnt that the hard way by buying a Numark turntable (possibly a tt-500) and found it to be almost completely useless for cutting. Maybe if a very heavy platter was added it could have served as something akin to a decent belt-drive, but I wasn't in a position to test that theory, and that was not really what I was going for.

[Dub Studio]

@Dub Studio - Besides the MK2 with the resistor mod to get up to 2kg, what do you think about the Technics SP-15 with 3kg starting torque for use with a VR and the precision platter? I'm researching all the available options on there and was thinking that would be a decent torque vs money unit...? Sure everyone wants an SP-10MK3 and all... but that price!

To the OP, the SP-15 does not hit the price point your looking for (more expensive) - apologies for thread jacking momentarily.

I wouldn't recommend any turntable based on spec alone, and that includes those used in some very high end lathes. The only way to know if a given system suits your requirements (more on this later) is to test it. The condition of an SP-15 is a factor, as speed problems have been reported with aging units.

It does have very similar spec to the SP-10 which is known to work (0.025 wow and flutter, direct drive, Quartz control). It has the advantage of being a little cheaper, generally, than the SP-10 but I believe this is reflected in the general build quality, being perhaps more aimed at a consumer market. I am not saying its a bad choice, but I would want to see a proven track record before advising its use, and even then I would want to check the unit first.

[Tom The Phonocat]

@Dub Studio - I am currently cutting with SP15. It has been freshly serviced. It can withstand around 70 g of weight. I also have a sp10mk2 and this can withstand easily around 500g.. Did a very non-scientific test. I bought myself a digital scale spoon (for spices and such). Placed a phone with a RPM measuring app on the platter and started to apply pressure with a spoon. These were the values which started to slow down the motor .. the Rotation was buttery smooth until I hit those... Of course..it may seem a childish way of checking it... but in reality, I cut on sp15 now and no audible wow even on 25 g. .. I have cut a groove as wide as 90um and no wow. Sp15 is a beast .

[Dub Studio]

@Dub Studio - I am currently cutting with SP15. It has been freshly serviced. It can withstand around 70 g of weight. I also have a sp10mk2 and this can withstand easily around 500g.. Did a very non-scientific test. I bought myself a digital scale spoon (for spices and such). Placed a phone with a RPM measuring app on the platter and started to apply pressure with a spoon. These were the values which started to slow down the motor .. the Rotation was buttery smooth until I hit those... Of course..it may seem a childish way of checking it... but in reality, I cut on sp15 now and no audible wow even on 25 g. .. I have cut a groove as wide as 90um and no wow. Sp15 is a beast .

Thanks, I am surprised there is such a big difference - 70g versus 500g! This would certainly encourage me to try an SP-15, but again I think the proof is always in the pudding.

Regarding the testing method, this seems like a good way to measure how the SP-15 would perform relative to the SP-10 which is known to work.

But as a general method, a few points spring to mind... firstly the friction from a spoon versus the friction from a stylus are probably very different. You can test this by getting a blank disc, placing a spoon with a known weight on the disc and tilting it til it starts to slide off. Then somehow perform the same test with a stylus (with the same added mass) digging into the disc. The difference in angle should give you the difference in friction. From that, you could work out how your spoon-based values relate to real world stylus values. You could instead attach a stylus to the spoon somehow for a more direct test of various turntables.

I have never heard of a digital scale spoon, you must be doing some very precise cooking I am wondering how it measures the weight of an object on such a large surface area. I mean the spoon's torque varies depending on the radius of the object being measured, surely? Perhaps it uses a parallelogram arrangement... does the spoon always stay in the same plane as the handle, or does the angle change? I would make sure the point of contact is always the same distance from the pivot anyway, just to be sure.

The other issue is the way in which we detect / measure wow and flutter? The phone can give us an rpm, and the ear can alert us to pitch / frequency changes, and I guess the strobe can also help visually. What does it take to convince you that the motor is good?

[Tom The Phonocat]

It's a cheapo scale:) I flipped the spoon part on it upside down and I applied pressure on the outer edge of the platter. It's the same method as placing your finger. but it shows the applied "weight". Yes. the difference is massive between those two. Sp15 has a heavy platter though. What's interesting? Stroboscope on the sp10 is struggling a bit but the RPM are stable! Sp15 doesn't have a strobe, unfortunately. I was using MK2, an external motor with a precision platter before that and I strongly prefer sp15. Quicker to work + runout is very very little and no audible difference. I recommend it strongly. Especially since we usually cut around 15 g, sp 15 is enough and if you can get it..seriously get it:) It's a really powerful and stable deck and no wow on the cuts.

I will be switching to sp10mk2 once my vacuum platter comes

Yes, my wifey likes to cook sometimes...im more of a walter white type cook haha

[Dub Studio]

Interesting... strobe sdturggling how in what sense?

[boryo]

I was using sp15 and was cutting heavy boom bap hip-hop without any issues, it worked perfectly. Switched to sp10mk2 just because I had good deal on it.

[Tom The Phonocat]

Interesting... strobe sdturggling how in what sense?

It's not 100% solid. It moves a tiny bit back and forth (by a tiny margin ), but the rotation of the platter is stable as hell according to the RPM app (wow and flutter values are also low)... This could be my SP too. I have a recapped BBC version with their microswitches.. it was a pain in the ass to revert it . I couldn't use the original Start/stop when i got it:P

[Dub Studio]

Interesting... strobe sdturggling how in what sense?

It's not 100% solid. It moves a tiny bit back and forth (by a tiny margin ), but the rotation of the platter is stable as hell according to the RPM app (wow and flutter values are also low)... This could be my SP too. I have a recapped BBC version with their microswitches.. it was a pain in the ass to revert it . I couldn't use the original Start/stop when i got it:P

Yeah, I wonder how accurate those markings are... I mean if the machining itself is off slightly, it's going to look like its not stable. I also wonder about the wow and flutter app... how accurate is that, and how can we know for sure?

[Dub Studio]

I was using sp15 and was cutting heavy boom bap hip-hop without any issues, it worked perfectly. Switched to sp10mk2 just because I had good deal on it.

Thanks for the info How deep were you cutting?

[boryo]

I was using sp15 and was cutting heavy boom bap hip-hop without any issues, it worked perfectly. Switched to sp10mk2 just because I had good deal on it.

Thanks for the info How deep were you cutting?

I don't know to be honest but I usually cut with 15-17 grams on head with dashpot. These are the releases I did with SP15 + some more for other people, mostly this type of music:
https://socialimpactrecords.bandcamp.com/album/post-tenebras-lux
https://socialimpactrecords.bandcamp.com/album/hoidan-mun-tontin
https://socialimpactrecords.bandcamp.com/album/props-to-all-jazz-cats-yes-yes-y-all