Vintage DD turntables. Are we living dangerously?

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Lewm, In response to your questions on 4/16/14 about the quilted material and the EMI shield I refer you to the "Nude Turntable" thread and my responses on 8/27/12 and 9/16/13, and the surrounding entries. Hopefully these entries will cover the ground.
Gary

Gary, I found on that thread or another DD-related thread that I first wrote about shielding the motor in my L07D, and you asked ME questions at that time. So I assume you proceeded from there, but to find out what exactly I am looking at in your photos, I will seek out the posts you cite. Sadly, the product "TI Shield" seems no longer to be available. One might use mu metal or ERS cloth or just a sheet of copper or stainless or etc. Each has slightly different properties as a shield.

... Always happy to learn and share.

Hi Gary,
I found your post of 9/16/13. I now know (once again) that your shield is made of mu metal and that the black stuff is auto interior material (which is exactly what it looks like). I probably also knew this 7 months ago, when you posted the info and photos originally, but the memory is fleeting. I found that same stuff on eBay that you have used. I Googled the eBay product, and there was some discussion that it is not as "good" as mu metal (it's a lot cheaper), but most conceded that it does work as a shield. I like your metaphor about squeezing a balloon, where you are describing what happens to the EMI when you installed the shield; the energy shows up elsewhere but not where you don't want it. Possibly, if you can ground the shield to the turntable, you would actually drain the energy to ground. But that may be tough to do.

I am going to get used to the sound of the TT101 with no shield, then install a shield, perhaps using the very same material you used, and see if I can hear a difference. I wonder whether some of the perceived benefits of those heavy copper platter mats are actually due to the shielding effect such mats have. If you read the verbal descriptions of the improvements in sonics, it certainly is consistent with the shielding effect.

Lew, I suggest that if you have or have access to an iPhone that you check out the Tesla app to see where the EMI is. You might not have a problem.
Gary

My intermittent speed problems on my Pioneer Exclusive P10 - racing up and down and failing finally became permanent.

Took the table into the tech and he said most probably changing all the caps would fix the issue. yesterday I got a call that the table was ready.

When picking up he said that replacing all the caps did not fix the problem. he searched the entire web and no schematics on the table. He eventually found it was a faulty IC from the 45rpm control that did not switch off and would distribute noise/interference to the 33 IC control.
these specific IC's had been long discontinued. So he studied a bit more and made his own! problem fixed.

the interesting this was that the tech had previously worked on Denon and Halcro's JVC DD's. Even thou they look similar from the outside, the internals and design's of all 3 were very different as was the number of parts, complexity etc etc.

I played it at home all last night and the speed sync's straight away and is playing beautiful music - fingers crossed it stays that was, but with the caps all changed on my 35 year old DD I have a fighting chance :-)

cheers

Downunder,

Great post, pleased you got that classic up and running. Perhaps your tech should make his substitute IC available to others.

Hi Albert

I have no technical ability, however I assume a really competent/talented technician would have the necessary skills to copy an entire IC, which is what he did.

Thanks to Halcro for recommending Chris Kimil, even thou he had replaced my Wilson tweeters. I did not realise that he fixed turntables.

I am even thinking now of having the tech replace all the 35 year old capacitors on my Exclusive P3?

Absolutely, I would do that.

Not only would new caps improve performance and reliability, it might avoid a failure that kills a hard to find part.

...I assume a really competent/talented technician would have the necessary skills to copy an entire IC, which is what he did.

Even if that were true, it takes all but a compact with the devil to locate such a person. Is there a N. American Chris Kimil? Not that I presently need one, but it would be good to have that name in the back pocket just in case.

At any rate, congratulations on renewed life.

There may be someone like Chris Kimil in St.louis, Mo, who happens to be the owner of Alpha Tech Electronics. His name is Zaah and the telephone number is 314-645-5250

Glad Chris helped you Downunder.....😀
His ingenuity, understanding and competence in all things audio are unequalled in my experience...
I took back my TT-101 to have him adjust the variable resistors for the platter brake system.
As I discovered....Victor added this feature to allow for the differing weights of various mats...and as I changed to only a thin Victor pigskin mat directly placed on the aluminium platter.....the brake system didn't perform as required. It took Chris precisely 20 minutes to adjust them ( one for 33.3rpm and one for 45rpm). No charge...😘 and they work perfectly..

I would waste no time in having him replace all the electrolytics in your P3.
Since my TT-101 had its done....the speeds are consistently perfect 😜

My guess is that Zaahs phone is about to get a few busy signals.

Let's hope you're right about Zaah, Audpulse. If so, it not only frees the mind regarding what we already own but also greases the wheels for future purchases. Thanks.

This guy Chris must be a gem, for sure. And by all means, Downunder, DO replace all the electrolytics in your P3. Like Albert says, you may save yourself a much thornier dilemma at some point in the future, if leaky caps eventually kill off an unobtainable IC. (But maybe there are no ICs in a P3 to worry about.) Now, onto the subject of "IC"s. It seems to me that they are not all created equal. There are some enormously complex and highly specific ICs at work in both DD turntables and in CDPs. Some of them have 16 to 24 "legs", and there are not even solder guns available to remove them from a PCB. That's why the common mode of repair is to throw the whole PCB away and replace it with a new one. Then there are ICs that self-contain a very simple circuit; I have to assume it was one of that type that Chris was able to replicate.

Hi Lewm

Yes, I believe you are correct. Chris said he replicated the IC with 7 components? That is about how technical I got or understood.
He did mention the Pioneer circuit board was the simplier of the three dd tables he has worked on.. The JVC and Demon were crowded and complex relatively speaking.

Yes Henry, excellent work from Chris indeed and thoroughly recommend him to anybody. Thanks.😇

And yes gents, I will have Chris take a look and replace all the caps for safety. 35 years service is pretty good and they may last another 35, but as you said if they fail due to age it will be good to safeguard it not have it happen.

I have asked my mate from Japan first to see if he has a Exclusive P3 Japanese service manual, but I doubt he has one, especially since Pioneer still service all Exclusive products in Japan.

Cheers and happy listening to all with their timeless Japanese DD tables 😁

Just completed a complete refurbishing / rebuilding of a Micro Seiki DDX1500 for a customer. These old machines are truly excellent. Did a speed check with the time line, over an entire album side the dot did not move from 23 feet across the room !

A nice little upgrade I did to was having the inside of the platter sprayed with Polyureah (Truck Bedliner), this silenced the bell like character of the platter nicely.

PBN / Micro Seiki DDX1500

Good Listening

Peter

As Halcro and I know, there is NOTHING in turntable land quite as complex as a Victor TT101. I haven't seen a P3, but the Denon DP80, Kenwood L07D, Technics SP10 Mk2 and Mk3 are as simple as a belt-drive, by comparison to the TT101.

As Halcro and I know, there is NOTHING in turntable land quite as complex as a Victor TT101.

Amen....😱⁉️....unfortunately...😬

By the way Lew....are you actually listening to a 'working' TT-101? 🎼🎵🎶

Nice use of emoticons, Halcro. One emoticon is worth a thousand tears.
My TT101 is working, if I leave it powered up at all times, and if I don't move it, and if I run it at least once a week. With those stipulations, it's "reliable". I have heard it play music, but my new problem is that there appears to be a short within the UA7045 tonearm wiring, such that I have no right channel. I need to change the tonearm on the QL10 plinth. Interestingly, the Fidelity Research FR64S has a requisite spindle to pivot distance that is compatible with that of the UA7045, so I should be able to pop in my FR64S in place of the UA7045.
I will do that one of these days, when there is no other "project" in the way. Also, I am enjoying the Beveridge 2SW speaker system so much that I tend to want to listen to music when I do get free time.

Interestingly, if the TT101 gets balky, usually after I have not used it in a long time, the cure is to whack the (front) side of the plinth nearest to the control panel of the TT101, with the palm of my hand. Very unscientific but works a treat. I am very convinced that there is a bad switch or a loose connection between switches that is to blame for the finickiness of the table.

For those who have a JVC TT-101 should check out this YouTube video.

DIY thread drive turntable

Looks like someone turned the TT-101 into a belt drive motor! Using string or thread that has no compliance, it retains the accuracy of the direct drive system with the isolation of belt drive.

Halcro, you should use the TT-101 to drive your TW Raven. :-)

I have used a Technics DD table that has pitch control driving a passive platter before and it worked!

.

Thanks for the Link Hiho...😍
Very interesting.....and nice music as well...🎶
I have seen that done before...as well as two Micro Seiki turntables running in line....using the one motor and a flywheel arrangement..👀
I studied this arrangement shown in the video for a long time.....whilst being somewhat troubled 😧 without knowing exactly why......⁉️
(Answer to the puzzle at the bottom of the page...😊)

This video demonstrates clearly how much 'thinking' some Japanese (and European) audiophiles put into the theory and philosophy of the turntable question...🔎🎼🔍💡😍
I love his obvious 'Copernican' view of the turntable surrounded by massive armpods 😘....and the 20" straight tonearm is fabulous...😜👏
He obviously prefers the ability to eliminate skating forces (no off-set angle on the headshell)....for the slightly increased distortion of 'tracking error'...⁉️
I wish I could see how he runs the thread from the heavy stainless steel platter mat on the Victor DD turntable 👀❓That is one massive 'pulley motor' 😎
Notice also his full horn speaker system....🔝🔚....obviously being powered by SET valve amps (although we don't see them 😰).

Answer to puzzle

The advantage of the very best DD turntables over belt-drives IMO....is their ability to cope with 'stylus drag' due to their torque and correction circuitries.
With the quartz-controlled motor attached to the platter and in close proximity to the stylus....any slowing of the speed due to 'stylus drag' is instantaneously corrected AT THE SOURCE..👍
When the stylus is separated from the correction circuitry by a thread a metre or more away.......the 'stylus drag' has a 'delayed' input which simply puts the quartz control 'out of sync'....😰

Halcro, I understand your concern and it is a valid one. When I used a DD table to drive a passive platter, I had to use the speed control and that required defeating the quartz lock feature to be at variable pitch since the two platters are not identical size. I confirmed the speed using a KAB strobe and it was rock solid. Of course you can always use the Sutherland Timeline if possible. I also did a experiment of using two identical direct drive tables one driving the other, one to one ratio, and able to retain the quart lock. And the sound is better than direct drive alone. But I ran out of table space! :)

I think using noncompliant material lessen the problem. I'm sure using a stretchy belt will throw off the speed in a weird way but, hey, we might like the sound! :)

Anyway, it's worthy experiment if you already have all the components and time. It's reversible. You have nothing to lose. The reason I did that was just so sick seeing expensive belt drive turntables using cheap flimsy motors and all that money was poured into the fancy platter for blinks.

Happy listening!

.

Would love to see photos or videos of some of your experiments Hiho....😉
You're a 'thinker' and 'doer'.....and we need more of those...👍

Kind regards....

Thank you for the kind words, Halcro. As a person with limited means, I'm more of a daydreamer than a "thinker." As for the "doer" part, I've been really lazy lately so I am more of a slacker. There you go, I'm a daydreaming slacker bum! :)

I didn't document much when I was experimenting so I don't have much to show. Here's one picture of using the guts of two Pioneer PLL-1000 tables, one driving the other via VHS tape. I even stuck a Lenco idler wheel in between at one point. Each has their own sonic signature. The tape drive version sounded the most balance. But when I switched to a JVC table I almost couldn't hear the difference. The idler drive one always sounded different, more robust and juicy. Nothing too scientific but it was all fun. :)

PS, This forum is more about validating one's (or invalidating other's) purchase decisions, almost like a consumer guide. It's a different platform from other DIY forums I frequent. I do enjoy out of the box thinking so this thread is quite nice. :)

.

I was going to take my Pioneer Exclusive P3 into my tech to have caps etc replaced. He asked me what was wrong with the table. I said, nothing but a few audiophiles said to take it in for preventative maintenance to replace the caps.

He said, changing caps will do nothing for the sound as they are part of the control the turntable speed in the dd table. With the dd tables, it either works perfectly, or it doesn't- simple.
He said tonearm and cartridge will have more impact on the sound than any changes you do to the table, as long as it is working to spec.
If it stops working like my P10 did, he will fix it.

Good enough for me. FYI - Lyra Delos for its comparatively cheaper price is world class. Syntax is correct, it is more resolving than the more expensive Kleos.

Cheers

Downunder, I've never read a claim that electrolytic cap replacement would improve sonics. But I have read advice from respected posters who know much more about electronics than I do that they can dry up or fail in other ways with age. The danger is not that they simply quit working but that their failure may take out other components, some which may no longer have replacements (ICs).

So your initial thought about "preventative maintenance" seems sound. I might look for a different tech. ;^)

Ditto to what Pryso says. Downunder, you might consider finding another "tech". The guy you quote is not very tech-y. As Pryso says, the reason to change out the electrolytics has nothing at all to do with sonics (unless a leaky cap is causing a speed error already). It has everything to do with the fact that electrolytic capacitors have a finite lifespan. Which is to say that after about 30 years since most of our dd tt's were made, the lytics are near pooped. A leaky electrolytic (either electrically leaky, meaning that it can pass DC, or mechanically leaky, meaning there is goop all over the outside) can and will eventually take out an IC or a transistor that may be irreplaceable. Call it preventive maintenance, if you are having no problems. Like changing the oil in your auto engine at regular intervals. For a great tt like the Pioneer P3, do it.

Dear Halcro, Headshell offset angle does have an effect on the magnitude of the skating force, but it is not the prime cause. The prime cause is related to the fact that nearly all tonearms are mounted such that the stylus overhangs the spindle. Thus the cantilever/stylus can never be tangent to the groove. (You are fond of Copernicus; now think about that other Greek, Pythagorus.) Since the cantilever/stylus is not tangent to the groove, friction between the stylus tip and the groove wall creates a force at an angle to the path of the stylus; a component of this force vector is toward the spindle = skating force. A tonearm with no headshell offset angle is not free from skating force.

Lewm/Pryso

thanks for your concern. but the tech has no concerns about exploding caps or his ability to fix if any fail, even thou there are NO technical manuals available so he will be going somewhat blind again.

This is the same tech that fixed my P10 and Halcro's DD's, making his on IC on the P10 so he is more competent than most - There was nothing wrong with the caps in the P10 either.

The P3 was serviced by Pioneer Japan before I bought it a few years back.

I actually slipped a disc in my back trying to move the P3 into the car, so off the radar for some time now. Does not mean I won't do it in the future, but anything this old can fail at any time.

The prime cause is related to the fact that nearly all tonearms are mounted such that the stylus overhangs the spindle.

Thanks for reminding me of this Lew...😊
I do think that in this case with his specially made 20" tonearm without an off-set headshell.....he probably also set it up on his pod without any overhang⁉️
I can't imagine what geometry he would use if he DID set up an overhang as he couldn't get zenith correct at the two nulls without twisting the cartridge...❓😎

Halcro, Lew,
A straight arm with no offset is normally set to one null point a little inside of the center of the recorded part of the record. I think this would correspond to 96 - 98mm from the spindle.

There is an arm like that now called Viv Rigid Float. It has won some accolades. I've never heard it. "They" say the benefit is from eliminating most torsional forces on the cantilever.
Regards,

http://stereotimes.com/post/viv-lab-rigid-tonearm

Fleib, another such arm that preceded the Rigid Float is the RS Labs RS-A1. As you say, it uses "under-hang" and thus achieves tangency at one point on the LP surface. Both of these arms are in the realm of the crazy, but I can say that the RS-A1 really works and sounds way better than I would have guessed. Thus I am curious about the Rigid Float. What bothers me about it is the question of whether the pivot is really held "Rigid" by the floating bearing arrangement. I don't see how it could be. The instructions that come with the RS-A1 suggest 21 mm of underhang is optimal (stylus hits the LP 21mm short of reaching the spindle) but this is more a suggestion than a rule.

Halcro, I agree that a 20-inch arm with a straight head shell would have very little tracking error because of its sheer length, and the skating force would be weaker than in most cases. But the trade-off is the potential for lack of rigidity of an arm that long, plus high effective mass. Interesting for sure, nevertheless.

Lew,
You mean 21mm short of the lead-out groove, which would be about 80mm from the spindle?

Reducing torsional affects on the cantilever is extremely important and obviously a tradeoff for alignment error. The Viv arm won a couple product of the year type awards so it might be very good?

I believe the pivot is held in place with some kind of magnetic fluid.
http://www.highend-electronics.com/viv-labs.html

Regards,

08-28-14: Lewm:
"What bothers me about it is the question of whether the pivot is really held "Rigid" by the floating bearing arrangement. I don't see how it could be. "

In the August 2014 issue of Stereophile, Michael Fremer reviewed the tonearm and wrote something about the bearing:

"The arm lacks a conventional bearing. Instead, the pivot floats on a dark, magnetic, light-viscosity, ferrofluid-like oil that you inject into a large opening at the front of the pivot housing. Before you do, the arm is too stiff to pivot; afterward, it smoothly glides on what appears to be a bubble of oil without visible means of support. According to inventor Akimoto, inside the pivot, a small ball floats on a “slimy rubber swimming ring that regulates the arc motion of the wand.” There must be a cup-like structure inside that holds the oil, and a vertical rod—the pivot point—that is somehow steadied by but floats within the oil. I couldn’t pull the arm to and fro, and yet it floated freely. Very ingenious, however it works!"

It sounds like the arm might be a modern remake of the Gray oil damped unipivot design using "magnetic fluid." But the distributor claims the following:

(1) Absolutely no mechanical contact at arm pivot bearing mechanism, resulting in highest sensitivity and maximum amount of howling margin (Which promises to reproduce rich but much tight base sound with no distortion, no muddiness, the most clear sound and wider dynamic range).
(2) There are similar type of bearing pivot, dipped in oil bath (Oil damp Type), available in the market, but still they require some string or another apparatus to fix fulcrum for arm rotary motion but RF, thanks to automatic positioning mechanism, requires absolutely nothing to interfere with the force, for cartridge stylus to follow the inward path of record groove.
(3) There might arise some lateral mechanical instability of arm with this type of bearing, but RF, equipped with the most appropriate balancing mechanism, assures the stability of the focus. This is the reason to be put the name of ""Rigid Float"".

So in the end, I don't know.

.

This tempts me to try my SAEC WE-8000/ST as a straight tonearm 😜⁉️
It comes with a ceramic off-set headshell but I use a whole lot of other headshells which I can use without twisting the cartridges as I currently do...😎
What do you guys think I should aim for as an underhang....bearing in mind the Viv Lab uses from 5mm to 20mm....👀❓

Hi Halcro,
You might have a problem with that. The arm is probably designed with at least 15mm overhang and with an SAE type headshell, chances are the cart will be too far forward. In order to achieve underhang you'll have to move the arm further back.

If you have some kind of arm pod set-up, this might not be a problem. Otherwise I think you'll have to drill a new armboard. I have an arm similar to a Graham Robin and no way without remounting.

I believe the alignment is 5mm toward the spindle from the center of the recorded part. That would be 95mm from the spindle, if I'm not mistaken.
Regards,

Correction - the lead-out starts at approx. 60mm and the record goes to 160mm, so I guess it would be more like 105mm from the spindle.

I have a few records that are recorded much closer to the label. You'd have to experiment. VE has a free download protractor called Chpratz. It's a calibrated straight line with a grid all the way and calibrated with distance from the spindle.

One thing that peaked my interest was a comment by one of the reviewers. He thought the shorter version of the arm sounds better - less resonance and vibrations. I was thinking of getting one of those straight arm DJ tables just to try it, but I couldn't bring myself to do it.
Regards,

Instruction on setting up the RS-1A tonearm using underhang scheme. I believe the arm uses the tangential point (or reference point) right in the middle of the platter which is 3 inches away from the spindle about 76mm radius.

"Structure & Features of RS-A1 Tonearm" by Shirou Horii

You can use that as a starting point to experiment with the SAEC or other available arms.

.

Hello Halcro,

Based on your experience, which JVC motor has morer torque,
The TT-71/81 or the coreless TT-101?

Thanks!

Doron

Hi Doron,
According to Vintage Knob...the TT-81 has 1.3Kg/Cm starting torque against the 1.8Kg/Cm for the TT-101.
I don't know how that relates to perceived performance as both decks are consistently immune to the the effects of 'stylus drag' even under three cartridges running simultaneously...😍
I also can't hear a difference in performance between the two decks in my system.....
Regards

fwiw, the manual for the tt 101 states 1.2 kg.cm as the starting torque.

Just for giggles, I looked up the starting torque for Lew's sp10 mk3: a whopping 16 kg.cm. But the platter for that weighs as much as the entire tt 101. So both tables reach operating speed in under 3/4 sec.

Well it seems both figures are as stated.

My original Japanese copy TT-101 1.2kg and the QL-10/TT-101 on TVK 1.8kg do show conflicting figures. Never noticed the
discrepancy before.

Hellow Fellows I have been following this thread with great interest,because for years I have been interested in DD turntables but have never taken the plunge, but think that I may be now ready.
Previously, I have been interested in the Dennons and Micro-Seiki primarily.
I would like to ask you folks would these two manufacturers be the ones that you would recommend or some other make as well?
I have previously been interested in the Dennon models DP 72 and 80.
I would appreciate any advice and or opinions that would be helpful.

Violin

Denon DP80 is a pretty serious drive system. If you can find one it will need to be restored. I'm currently working on restoring 3 each DP3000, one DP2000 (they share the same motor) and one DP80, most definitely the best of them.

The Micro DDX 1500 is very nice too but much harder to come by, I restored one of those a while back DDX1500

Good Listening

Peter

violin:

If Halcro is right in his assessment, I should think that the victor/jvc tt 81 is unbeatable for the price and availability (yahoo Japan always seems to have a handful of them at any given time). Raul was very high on the denon dp 75, so that could be a consideration. I owned a technics sp10 mk2--that's very good. I've always gravitated towards the pretty Pioneer stuff (pl50ii and pl70ii).

The list goes on and on.

Thanks, Halcro!

Hi Halcro,
I have a few more questions if you don't mind.
Acquired a TT-101 motor on ebay.
Arrived today and I unpacked it and was shocked:
At first glance it appeared DOA.
Without the platter installed, as you press 33 or 45, the spindle is making grinding noises and never gets to the proper speed (33.33 or 45). The LED display shows the motor is rising in speed to random numbers below the required speed and then the counter goes back to zero and re-starts again.
Putting the internal counter switch on "hold" gets this re-counting to stop but again, speed never gets to either 33.33 or 45.

When assembling the platter on the spindle, the bottom of the platter scrapes against the base underneath it and when pressing the 33 or 45 does not turn at all. On a closer look you can see that the platter is eithef not concentric with the base's outside diameter, is not sitting in the centre as if the spindle is bent or out of centre or sitting too low.

On an even a closer look yet, finally picked on what's wrong:
The spindle is a cone which enter an opposing cone in the platter's hole.
It seems that either the spindle cone "shrank" from its original size and/or the opposing concical hole in the platter "expanded" or the spindle sits too low to engage and support the platter above the base.
The size tolerance could have been a temperature issue (expansion and contraction).
End result is that the platter sits too low and scrapes against the base,
So? I took a skinny tape and put on the spindle cone (like a very thin shim) and guess what? The platter locks on the right speed, it rotates quietly and stops on a dime when I press the stop button,
So few questions:
1. The spindle seems to have axial freedom/clearance. In other words without the platter, when I gently pull the spindle it comes up a few thous. I have noticed this on my TT-71 motor too. I assume it is relying on gravity and the motor bearing is not a thrust bearing but not sure.
From your experience, is this slight axial freedom normal?
2. When trying to rotate the spindle without the platter it seems noisy and doesn't lock on 33.33 (it does on 45 but takes a while).
As soon as I put the platter on, its dead quiet and locks beautifully on both 33.33 and 45. Is this normal? Does your TT-101 functions similarly?
3. What's with the spindle cone/platter matching cone clearance?
Have you ever experienced such an issue?
Could it be a shipping damage (bumped on the floor and the spindle moved down from its original place, which would have resulted in the same exact result?

Any additional thoughts/advice would be most welcome!

Thanks and kind regards,

Doron

I would not recommend running without the platter,often will cause lots of issues with speed lock etc and possible damage.

As to the issues was the table shipped with the platter mounted?

From your description you may have damage to the
platter ie lost tolerance of the mating area due excessive
shock.
The scraping is yet to be determined likely related to what caused the platter deformation issue.

Not a great way to start your Victor experience.

Doron:

Platter height is adjustable via a screw at the bottom of the unit (where the bearing is). You'll have to take off the metal cover to access it. It is cemented into place per stock, but perhaps the previous owner messed with it. Scraping is likely due to the platter being too low. Mine was the same way. Perhaps the bearing oil ran out or up due to shipping, thus causing the platter to sink ever so slightly? You might wait a day or so to see if it self corrects before messing with the bearing screw.

As Totem said, don't run motor w/o platter. It's calibrated for a specific load, so it shouldn't lock speed w/o platter. I'm surprised to hear that it locked at 45 for you.