Cartridge?
Linn LP 12 hum not coming from Bryton phono stage.
I’m getting a pretty significant hum with my Linn Sondek LP12 turntable sitting on top of my equipment stand. My new Bryston MM phono stage does not hum at all when the turntable RCA interconnects are disconnected.
Yes, I have the grounding wire attached to the grounding lug on the phono preamp. I plan to move the TT to the original Sound Organization wall shelf to get it away from the adjacent electronics.
Will moving it to the wall shelf do anything to eliminate hum? What about transitioning to the better "Radikal" power supply and DC motor (the original has the Valhalla board I believe and the AC motor).
Thanks, for any suggestion you might have for things I can check.
edit: I must be tired, I noted that I mis-spelled Bryston as "Bryton". Titles cannot be edited, arghh!
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Thanks for the replies, the cartridge is a Linn K9 MM. I did move the table to the other end of my double wide equipment stand. It definitely hums when playing music - which kind of stinks because my digital system is dead quiet. No WiFi or routers are nearby. I will have to check and see if it hums while the RCA's are connected but the power cord is disconnected. I will be taking it in to get an upgraded (Radikal, Akurate chassis) power supply and motor later this summer. It will be interesting to see if this eliminates the hum. |
@daveyf - I'm glad to hear you say that the Bryston Phono stage is really good. I don't have much to compare it to other than the one in my old NAD pre-amp. The gain on my MM only stage is a bit lower apparently than is should be because on some records I have noticed a need to turn the volume control up quite a bit higher compared with my Sony XA-5400ES SACD player or my Wadia -171i iPod dock. |
Have you noticed whether the intensity of the hum changes as you listen to an LP, from outer grooves to innermost grooves? If not, you might do that experiment and report back. Absent a defect in your current power supply, I doubt that the PS itself is the problem. Or to put it another way, don't spend the money on a new PS solely in order to cure this problem. |
@lewm - I have noticed that occasionally the hum increases after the turntable has been running for a bit. I mean when I first turn on the turntable the hum is barely audible. By the end of the first side of music, it starts to become intrusive. I had already planned to update the power supply for the supposed improved sonics and the ability to play 45's. |
I'd start by checking the headshell wires of the K9. Sometimes they can get too close to other pins. If so you could try to move them with a small non-metal implement like a toothpick etc. Just to see what happens to the hum. You could also check the mains cable by moving it to see if that has an effect. Loose connections are notorious for causing hum issues. As for the Valhalla board, I would not recommend an examination. It carries lethal voltages and you would also risk disturbing the suspension. Without the correct suspension setup, the sound of an LP12 collapses pitifully. It might well be possible that the thin earth lead which grounds the sub-chassis may have strayed a little and is now picking up something from one of the board's high voltage components. In this case you will be better off getting it checked by someone who has the required setup jig. They'd be able to take a closer look and give it a service and oil change etc at the same time. I'm also far from convinced that the Linn belongs on a wall shelf. It's suspension can cope remarkably well with vertical resonances sat on a table, but not so well on a shelf with resonances coming from a wall. However this is what I found some 15 - 20 years ago. Linn may have changed the suspension components a few times since. You should definitely consider ringing a dealer or maybe ringing Linn themselves. Sending an email certainly won't hurt either. Turntable hum is the nightmare of every vinyl enthusiast, so the best of luck in getting it fixed |
Update on my path to quieting my phono(Linn Sondek LP12 w/ Bryston BP-2 MM is overdue... I returned from Ann Arbor Michigan where I had taken the turntable to Overture Audio and Thomas O'Keefe there did a fantastic job doing a whole bunch of upgrades on it. I lost the Valhalla power supply and now have the Radikal power supply. I went all in and have the new Karousel bearing installed on a Greenstreet Audio (Keel copy) CNC milled aluminum subchassis. I got the "Adikt" MM cartridge to replace my aging K9 cartridge. When I hooked it up, it still hummed! So I contacted Gary Dayton with Bryston and he said that I need a "Y" connector to go from my BP26 preamp to Bryston Power supply. When I first hooked it up it started making a police siren sound! I freaked and had to power the system down since the police siren noise was increasing in volume. I had to take a time out and go out and do some yard work as I pondered what to do next.... Update to follow since I am at work right now and my laptop is about to die.... |
Well, this is getting exciting! I assume they tested the Sondek and gave it a clean bill of hum-less health. So something’s got to be up with your phono amp. You need to test this with a different phono. Buy a Schiit Mani on Amazon for $149. Or even a $30 cheapo unit. You can return it or use for another table. |
@masi61 Sorry to hear of your continuing issues...this hobby can be more than frustrating at times! Since Thomas OK set up your table ( which with the new upgrades should be stellar), I would not expect any issues with the table. OTOH, hum is usually caused by an improper grounding scheme. You should be sure that the Bryston and the tonearm phono cables are grounded through your preamp...( making sure that the connections are clean and good on the grounding wire!). If the problem persists, i would check and see if the phono stage is grounded and if the preamp is likewise. If the hum is still an issue ( and it sounds like it might not be hum at this point), then i would be tempted to have the Bryston looked at by a Bryston rep. One other thing, if I remember correctly from the time i was listening to the Bryston, it has dip switches inside it to adjust the gain, you should make sure these are set for the value of your new cartridge! |
Thanks for your interest @noromance & @daveyf . I had a hunch that the Maze Audio Krell cryo power cord that I had running to my Bryston BIT-15 power conditioner from the wall might in some way be contributing to the wild "siren" sound loop that went nuts when I turned on the phono input. So I put the stock cord back on. The wild shrieking sound mostly went away, then after a time it appeared to completely dissipate. The "Y" connector taps into the umbilical power cord that runs from my Bryston outboard power supply and BP-26 preamp. It does appear to that everything is operating normally now. My tonearm cable has not one but two grounding wires which are both connected to the Bryston phono stage. Other than RCA interconnects from the phono stage to the BP-26 preamp I do no see any option for an extra ground wire to be run between the 2. Yes Thomas tested my LP12 for hum and it actually had NO hum issues before or after the installation of the Radikal power supply and motor upgrade. Right now I'm just beginning the process of listening to a bunch of my old and new vinyl records. The sound quality is really, really wonderful so far. I am out of practice with my vinyl care and have lots of questions. I'll probably continue to write about my experiences with all of this. Strangely, with the Adikt cartridge twice now at the end of the record, the stylus just kept on going and skated right onto the paper disc in the middle. I did use the tonearm lift quickly both times so hopefully the stylus is not damaged by this. |
@noromance - The Ittok was tested by Thomas as part of my turntable service and he said is "exceeded spec" with the pendulum test. I think the couple of times where the needle skipped onto the paper lable was right as I was about to reach for the tonearm lift and inadvertently jostled the suspension simultaneously. Apparently I drink too much coffee or I am developing a tremor.... but just to play it safe I have been very attentive as I listen and get up out of my chair promptly near the end of the last song on each record side. |
@lewm : I was definitely concerned that the sound was getting louder. I plan to message Maze Audio about what happened. When I installed the "Krell Cryo" power cord from the wall outlet to my power conditioner, it did not seem to change the SQ much but I have 2 more of the same power cords. Another one runs from the power conditioner to the power supply for the Bryston BP-26 preamp. It did impact the SQ if I recall. I think it made the sound quality more detailed and dynamics more prominent. But why a my phono stage would go crazy just being turned on (without even playing a record yet) is bizarre! Apparently there was some feedback loop that got triggered, but how? |
There may be a problem with the cables. No idea what but they're possibly fakes. https://www.diyaudio.com/forums/power-supplies/342718-plese-help-krell-branded-cables-found-online.html |