Hum in Pro-ject Debut Carbon TT - getting better!
Hi. I haven't been listening to vinyl records for a time and now that I'm back, I have noticed some background hum. It's not the typical hiss inherent in phono preamps when you turn up the volume, it's an added grainy hum. It's present with my old amp and also with my new ifi set (zen phono and zen can headphone amp). The sound changes its character and loudness if I touch the RCA connectors, be on the TT or on the preamp).
Any idea? Advice welcome! Thank you!
Hi. I haven't been listening to vinyl records for a time and now that I'm back, I have noticed some background hum. It's not the typical hiss inherent in phono preamps when you turn up the volume, it's an added grainy hum. It's present with my old amp and also with my new ifi set (zen phono and zen can headphone amp). The sound changes its character and loudness if I touch the RCA connectors, be on the TT or on the preamp).
Any idea? Advice welcome! Thank you!
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Today I was going to buy another cable to try, at this moment I only have the one that came with the Pro-ject. And yes, the TT is grounded to the phono pre. In fact, the hum is the same you get if you leave it ungrounded, but quieter (still quite audible and annoying).
I have the essential iii. Not a fan of the rca cables. My meter picks up all kinds of leaking from it
I live in an area with all kind of **** waves around. My guitar amp also hums like crazy in some rooms, picks up radio stations and that kind of annoying bs. There's even one spot in one room where you can watch TV without connecting it to the antenna...
I picked up hum from a phone base - I had to move the phone base into the bedroom and the slave phone into the lounge as it transmitted hum across the room.
Try the TT in a different room; if quiet you are one step closer to identifying the source of the hum.
If no different then look into cabling & grounding issues.
Try the TT in a different room; if quiet you are one step closer to identifying the source of the hum.
If no different then look into cabling & grounding issues.
I've tried other locations but they are not so far away from my phone base, so... I'll try putting the base and the phone as fas as I can, and let's see. Thank you!
Briefly unplug the phone base. That will prove if it is a source of noise.
I suggested moving the turntable as you stated you had multiple sources of noise.
The phone base was given as an example as it was a less obvious source and it sounded exactly like mains hum which it wasn't. Fluorescent tubes are another source.
I suggested moving the turntable as you stated you had multiple sources of noise.
The phone base was given as an example as it was a less obvious source and it sounded exactly like mains hum which it wasn't. Fluorescent tubes are another source.
Well, it's not the phone base, and the are no fluorescent lights. I think the system is picking up something. When I simply touch the connectors (just the plastic cover, not the metallic part) the hum is louder, as if my body is acting like an antenna. I think I will have to try different placements. Maybe better cable?
Things are going better: changed the cables. I bought a Pro-ject Connect-it and the hum has been lowered a lot. It's still present if I turn up the volume to the max, but in a quite lower level. Good enough in a normal listening level. Anyway, I will try different locations too, to make it even lower.
I assume this noise is is coming when the arm is lifted and not playing a record.
1. I bought a 2nd hand SME 3009 II arm and it hummed. If I moved the cables around the hum level and sound (50 Hz and subsequent harmonic levels) changed dramatically. I found that the arm had been re-wired, and the L and R ground connections from the cart swapped over where the cables go onto the adaptor at the base of the arm. After I corrected it, the arm was perfect.
It’s a long shot, but check you have not swapped the ground wires on the cartridge side which would produce a similar issue.
2. To check if the hum is coming from the motor radiated field, with the platter in rotation, move the arm in the lifted position from the outside of the platter to the inside - ideally you should get no noise. Most T/T’s put the motor in the far left hand rear corner of the base for this reason, but you should check in any event.
3. Separately, some of the Project T/T’s have serious motor vibration issues that manifest as something that sounds like hum, but you only get this with the needle in the groove and not when the arm is lifted in the up position.
The cure in this case is to make sure the motor screw mounts are not too tight, thereby over compressing the rubber isolation rings - you really need to play around with this to get it right. Further, you can also buy an upgrade kit from Henley Projects that gives improved isolation grommets, a different kind of belt and some other stuff. I got one and it made a big difference. (My son now has the T/T - works well and sounds good).
1. I bought a 2nd hand SME 3009 II arm and it hummed. If I moved the cables around the hum level and sound (50 Hz and subsequent harmonic levels) changed dramatically. I found that the arm had been re-wired, and the L and R ground connections from the cart swapped over where the cables go onto the adaptor at the base of the arm. After I corrected it, the arm was perfect.
It’s a long shot, but check you have not swapped the ground wires on the cartridge side which would produce a similar issue.
2. To check if the hum is coming from the motor radiated field, with the platter in rotation, move the arm in the lifted position from the outside of the platter to the inside - ideally you should get no noise. Most T/T’s put the motor in the far left hand rear corner of the base for this reason, but you should check in any event.
3. Separately, some of the Project T/T’s have serious motor vibration issues that manifest as something that sounds like hum, but you only get this with the needle in the groove and not when the arm is lifted in the up position.
The cure in this case is to make sure the motor screw mounts are not too tight, thereby over compressing the rubber isolation rings - you really need to play around with this to get it right. Further, you can also buy an upgrade kit from Henley Projects that gives improved isolation grommets, a different kind of belt and some other stuff. I got one and it made a big difference. (My son now has the T/T - works well and sounds good).
Thank you for your long response!
I bought the TT new and from a serious dealer, and I haven't touched the cartridge (in fact, I even haven't changed the stylus yet). So, as far as the TT have that been well mounted in the factory, I think that's not the problem.
The hum is present with the platter not rotating, but I will try what you say, moving the arm, to see if there's some change.
But the noise has been lowered a lot with new cables, so I think it must be some grounding issue, or the TT is picking up some kind of waves.
I bought the TT new and from a serious dealer, and I haven't touched the cartridge (in fact, I even haven't changed the stylus yet). So, as far as the TT have that been well mounted in the factory, I think that's not the problem.
The hum is present with the platter not rotating, but I will try what you say, moving the arm, to see if there's some change.
But the noise has been lowered a lot with new cables, so I think it must be some grounding issue, or the TT is picking up some kind of waves.
That’s great. My original Project T/T was also a Carbon with a Ortofon Black cart.
BTW, make sure the T/T ground wire is attached to the phono pre casework because if not, you will also get serious hum.
Hopefully you can resolve it and enjoy your vinyls.