Hi. I'm not a newbie at all but haven't experienced this before. An old friend passed away and left me his Micro Seiki RX-5000 turntable with a Grado Laboratory Reference Signature tonearm. It required some work since it hadn't been played in many years but I refurbished it and put a Dynavector Te Kaitora Rua cartridge on it. Sounds great, but.... It's massive at a 100lbs plus motor and power supply. The platter is solid brass. The issue is static, not the normal type due to a dry room. At the end of an album when I touch the cuing lever there's a big snap to the point of being painful. I think it is contributing to a bit of noise as well. If I walk around the room a bit when it isn't running and go over to it, no discharge. I'm playing with two mats, a multiply Soundeck PM and an acrylic one. Not sure which I prefer but it's not due to a felt mat. The bearing is sealed and seems to spin forever. No noise with a stethoscope. It is securely grounded to the phono stage. I'm at a loss as to what's causing the buildup. If the bearing has an issue, could that be the cause? I've no experience with that. Sorry for the length. Figured I'd try to anticipate questions. Oh, old turntable is Rega Planar 10 with the same cartridge and no similar issues, especially in the humid summer we're now having.
It's not really clear how you are handling the grounds. The Grado DIN cable will have a tonearm ground that is connected to the phono preamp, but I think there are also ground wires from the motor unit and the platter unit. Are you using belt drive with the motor unit installed on the platter frame, or string drive with them separated? Static is a difficult subject, are you getting zapped when touching other pieces of your audio gear, like the preamp chassis? Or just the turntable? It's a different subject, but the bearing isn't really completely sealed. It is very close tolerance on the shaft, and I think the thought was that it would never need service, but I also don't think they anticipated 50 years into the future. The bearing on my BL-91 is similar, and I did service it, and many others are servicing the bearings on the 1500 and 5000 units. If you want to visit a board with a lot of users, check out Romy's place and search for Micro RX-5000, one guy even had the old oil analyzed by a lab to help the community determine the best replacement (and it did use some lead in the oil, as speculated online), below is what I used ... GoodSoundClub - Romy the Cat's Audio Satire
Thanks for the reply. Yes, the only ground is the one on the phono cable. I suppose there could be an issue with it but removing it from the phono stage does add a bit of hum so I assume it's doing something. The power supply is not grounded. I assume, perhaps incorrectly that it would not be involved since it is not touching the table and only has the rubber belt in common. I've considered the thread but not sure how you go about it these days. Used to have a Well Tempered that used fishing line and I made those and the knot wasn't a concern. I've not seen a ground point on the chassis for the bearing or platter. I'm familiar with Romy's, only in researching the CU-180 mat. I'll check further there. Thanks again. Inc incidentally, the charge occurs when the platter is turning, whether the tonearm is in use or not. Oh, and no, nothing else has an issue, including my Rega Planar 10 when I hooked it back up to check.
I don't know the Grace tonearm so not sure how the parts of the structure are tied together, or whether the ground wire in the DIN connector is enough for the whole table. I'd suspect there should also be a ground wire from the platter frame structure to the phono preamp, but good luck getting it resolved, that is really a super table you have now. Any plans to add more arms? As you'd probably imagine, the extra arm mounts can get very expensive these days unless you really luck out. Sometimes they show up on hifido for somewhat reasonable prices, but they are rare, and you need the specific one for your tonearm mount. Anyway, when you get it all situated, we'd love to see some pictures, there's the big turntable pictorial thread, that would be a good place.
For the record it is what was Grado's Signature arm. Like you I'm not sure about how it's grounded. Since our last contact I have grounded the motor assembly and attached an alligator clip lead from one of the wing nuts at the base of the tonearm, both back to the grounding lug on the phono stage. No appreciable difference although the problem seems to have lessened a bit even before I quit listening last night. Seems to be a variable but no idea what. At its minimum it is more like a dry weather snap, which I have always assumed is the static electricity in me touching the grounded tonearm. Will do on the pics. Don't know about another arm. The one on it is one of the two quite large ones. I also have another that was provided to me with the table, much smaller. I'm fairly severely visually impaired these days (wet macular degeneration) so if there is an issue with the bearing, or one develops, I would have to hire someone to do the work. I can see but my central vision is completely gone. Thanks again for taking the time. This thing sounds so damn good....
Maybe try a mat that is conductive rather than insulating? I had one years ago for a Linn. They aren't terribly expensive. Then make sure the turntable chassis is grounded also.
Thanks but I've used no mat, the acrylic, a constrained layer one, felt, and cork. No discernible difference.
I don't know what the root of your static problem is. You may want to call in someone that has a lot of experience working on electronics and can pinpoint the source of the static, whether it is the equipment itself or the environment. A couple of years ago there was a guy that was getting static so bad he was frying multiple pieces of gear. In the end he had to rig up a discharge system for the tonearm and put an antistatic mat on the floor in the front of the TT. Good luck. That's a very nice turntable there and I hope you can solve the issues. My condolences re: your friend.
Hi Davey. Hope you don't mind one more question - The owner's manual on the 5000 breaks the different components out with a list of accessories. Under "Frame" one of the accessories is a ground wire. Interesting. That obviously creates the question of a need for the frame itself to be grounded, in addition to the tonearm and the motor. There are a couple of small holes on the side under the armboard that don't go all the way through. I know zinc is only about 1/4 as conductive as copper (much like brass) but would still conduct. Do you know if and where the frame should be grounded? Thanks again. Think I'm going to replace the tonearm with a Dynavector 507 MKII. (I'm a dealer)
I'd probably just run a ground wire to one of the screws on the platter bearing bottom cover, that's the way it is on my BL-91 as shown below, but my plinth is wood so can't rely on the frame to make contact with the bearing housing. You may be OK just attaching a ground somewhere else, or you may be OK the way it is, I don't know if your tonearm makes electrical contact with the frame. In the end, you should have some level of resistance between the spindle and ground wire, it won't be a direct short since there is an oil interface, but it is very thin layer and somewhat conductive...
Found this picture below, looks like there is a ground post on the bottom on the left side in the picture, does yours look like this?
A one sided carbon fiber mat will extend the platter metal post ground over the entire record with a non conductive platter. Frankly I always preferred metal platters.
Oh confused wood plinth for platter. Why poster thought a wood plinth makes any difference in grounding is beyond me.
There ya go - you can now ground the bearing/platter, add a conductive platter mat (they are plentiful and cheap) and you should be fine.
Not the issue I was fighting bug good advice. I ended up with the Micro Seiki CU-180 solid copper platter. A metal platter with a metal mat should ring like hell, right? Nope. Perfect. Total dead when you do the fingernail flick (very technical) but the music is totally alive and well balance. Take care.
I believe I finally figured things out. The belt that was on it was quite old so I figured I would do some preventative maintenance and purchased a gneric belt from eBay, generic in that it is a modern belt but was advertised for the RX-5000. I was slow figuring out cause and effect. It seems to be this new belt that was causing the variable static issues. Some LP's were worse than others but it seems clear. I had difficulty accepting this was a factor: rubber doesn't conduct electricity, right? However, rub a balloon against your hair and tell me it can't cause static. I suspect, and this is conjecture, that the new belt was rubbing/slipping on the platter and creating static, that was being discharged and picked up through the cartridge. I put the original belt back on and the incredibly silent noise floor returned (not counting normal surface noise, although they were less intrusive) and I haven't experienced the constant static discharge and sometimes extreme surface noise that I had been getting. This guy runs on a belt or a special thread. I'm going to try the thread since that is Micro Seiki's preferred method. Thanks to all for contributing.
Hi. I hope you're still open to questions from me. There have been a few changes since my last post here. I changed the arm from a Grado to a Dynavector 507 MKII. The cartridge is now a Dynavector XV-1S. I found what seems to be the perfect mat, a perfectly flat Micro Seiki CU-180, solid copper one. Romy is convinced that I have a bearing issue. He may be right. I don't recall if I mentioned that the table was literally sitting in one place, unused, for over 20 years. It belonged to a friend of mine who basically quit using it with the advent of CD's. He was also my lawyer and a customer of my audio store. He like the way it looked but I know it's whole history going back 35 years. I'm visually impaired these days with wet macular degeneration. I'm not blind and function reasonably well but have no central vision. I have a good friend who helps me with things like this these days. I suspect at a minimum the bearing should be lubed. The fact that it has had relatively little use compared to its age may mean the bearing is OK. I don't know how to find out how to proceed. Can you point me at something specifically? I have to have things read to me on a computer and trying to slog through stuff on some blogs, including R/omy's, can be tough. Thanks and hope things are going well for you.
I'm not completely clear on which issue you are now working, didn't you indicate the static went away in your last post? If the table hasn't seen much use, I wouldn't worry too much about the bearing, it is sealed on the bottom and very tight clearance around the spindle, so should be OK. But you can take off the platter and turn the spindle with your fingers checking for smoothness. You can pull up a little on the spindle a few times to help oil migrate up the shaft. As I outlined above, I did take apart my bearing and clean it up and replace the oil with Mobil DTE 25 Hydraulic Oil, but I'm a steady hands DIY guy with good vision and take everything apart, whether it needs it or not https://www.mobil.com/en/lubricants...lubricants/product-series/mobil-dte-20-series
Yes (thought I had it figured out), I mean no, I mean, mostly. This has been an adventure. I was looking for one issue/solution but I believe several factors were at work. My monoblocks are Classe Delta's. The feel barely warm on top but the heatsinks are on the inside and they have a tunnel that blows very hot air out of the rear. Kind of like a hair dryer on lower. My humidity was extremely low. I'm changing amps plus adding a humidifier so that should be resolved. Added a DS Audio ionizer which I didn't want to improve things, but it did (subtle sound improvement, not the earlier issue). The reason for my question is something I noticed and also a comment that Romy made. I tried the Aramid fiber, K5, whatever thread drive MS recommended and it would work for a while then slow down. Consistent but about half speed. I was actually asking about available drive belt sources but Romy said he thought my problem was bearing related. That makes sense to me. The thread belt has more slippage by design, but if there's too much drag with the bearing that could slow it down. That's the reason for this contact and I hope it sounds logical to you. To complicate things further, I also think I'm starting to have an issue with my phono stage. Good news is I have a T+A P3100 HV preamp with optional phono board on its way so that should fix that. I strongly suspect that, if anything, the lube would make sense. I did figure out how to follow the Romy posts, which are a bit different. I'm legally blind (not blind, blind) so I have to have things read to me by my Mac and the site is kind of difficult for me. Mainly I want to figure out how to work on the lube situation. I'm used to dropping a few drops of pure synthetic oil in the shaft onto the thrust pad. Thanks and sorry to bug you. (I can't see what I'm typing and have had a glass of wine so hope it makes sense
No problem, but I don't really know what to tell you that I haven't already said above, and your limited vision would seemingly make working on it kind of difficult. I generally test the bearing by measuring the spin down time from 45rpm. I have a hall effect tachometer on my deck to measure the platter speed, so remove the belt and spin the platter by hand, and then time it from 45rpm until it stops. Mine is between 3 and 4 minutes spin down when lube is fresh and not under heavy load (I have some magnetic levitation on my platter so loading is pretty light with no mat or record or center weight). Yours would be a much heavier bearing load, not sure what spin down time you might expect to get, though you could compare it to someone who has serviced the bearing and is confident it is working nominally. The bearing on my Micro BL-91 pictured above is the same as the RX-1500, but not quite the same as yours, and mine has the aluminum platter instead of the much heavier gunmetal.
I owned a high end audio store for 30 plus years and a good friend who worked there as well is helping so should be OK. Yeah, I've seen some other pics that make it pretty clear. I tend to overthink things at times. I think once I see it, and I'm not blind, just no central vision, it will be clear (pun intended). Thanks again. Did pick up some of the lube you use.
@Richard Milam congrats on finding such a turntable and happy to hear that you've got it sorted out. This, SX-8000, Verdier la platine, and Nottingham Hyperspace were the turntables I was looking for when I was still listening to a lot of vinyl
STATIC ISSUE FINALLY RESOLVED!!! I thought I had it a couple of times but kept coming back. Thanks to Garth at Audioquest I've determine that the problem isn't the table at all. It's the phono stage. I was getting five or six pops plus statics every time I used the tone arm lift after playing. A couple of times the LP didn't want to come up from the platter. Garth said he has seen this happen when a cap has gone in the phono stage. Changed to a different one and no static, no hum, no crackle. Thanks to everyone for helping me learn so much about the table, even if the problem was elsewhere. Sorry to waste your time. Still going to lube the bearing since it seems to need it. Anyone have a suggestion for replacement bearing should this one be worn? Thanks again.
Do I understand your post correctly? Garth @ Audioquest says a bad cap in a phono stage can cause static issues and cause an LP to cling to a platter? As strange and unlikely as that sounds I'm glad you seem to have sorted the static out. What phono stage did you get?
