Garrard 301 Humming

[Dunloy3]

Any thoughts/ solutions as to why my turntable hums- even when switched to off but still plugged into the mains.The turntable is connected to a pro- ject phono stage that connects to a Naim preamp and then to the Naim power amp- the noise increases if I touch the tonearm or the earth socket on the phonostage.Help!

[Nickthedentist]

Just to be doubly clear, am I right in thinking the hum's coming though the speakers, as opposed to from the turntable itself?

If the former, please post pictures of how it's wired up. Sounds like an earthing ("grounding") problem.

[Edward Huggins]

Two pre-amp stages??

[Gabe001]

Follow this thread, same issue
https://www.vintage-radio.net/forum/...d.php?t=209713

[peterpiper]

Hi, I've restored a few 301s and found that the capacitor across the motor mains switch is leaky, sometimes even making the motor turn slowly even when the switch is off. Peter

[Dunloy3]

Thanks for the replies and will try to answer all points raised-the hum is from the speakers and persists when I turn the Garrard off but leave the power cable connected.The Garrard is connected to a Pro-Ject Phono Bow E and this connects to the Naim Nac 72 preamp via the phono terminal as the Naim does not have a phono stage.The Nac 72 has a separate custom made power supply and the preamp is connected to a Naim Nap 180 power amp. I also have a Pioneer CD player and Pioneer streamer connected to the system but these are selected via a 3 way RCA switch box.The link to the similar Garrard SP25 hum made no sense to me at all as my tech knowledge is zero and I have no idea what or where the capacitor would be- one thing is certain-the hum is driving me mad and to make matters worse both Kef Q speakers have an annoying background rattle.

Help!

[Nickthedentist]

Thanks for the updates.

You say that the hum "persists when I turn the Garrard off but leave the power cable connected.".

So, with the amp and preamps plugged in and switched on, but the Garrard unplugged from the mains supply, place the stylus on a record and rotate the platter manually.

What do you hear then? Sound from the record but with NO background hum?

[Dunloy3]

Thank you for the reply-I unplugged the Garrard from the mains and fired up the pre and power amps but without even putting the cartridge on a record the humming noise was there.I touched the tonearm base and the phono stage base and the noise increased- the humming only disappeared when I pulled the power cable out of the phono stage-any thoughts/ solutions to this issue and the speakers making a rustling noise would be greatly appreciated.

[williamsunique]

This sounds like an "earth loop". If the 301 is connected to earth then disconnect this earth. If it is not then try connecting an earth to it. Try the same with the project phono and your Naim pre-amp and Naim amplifier.
In the majority of set ups the "earth" connects through all equipment by the screened lead of the interconnects. As a general rule only one "Earth" is required this then connects to all equipment via. the screening on the interconnects.

Paul

[Dunloy3]

Paul- the Garrard has an earth wire as part of the cable that is hard wired into the base of the tonearm- this earth wire connects to the earth screw plug on the phono stage but when this wire is connected or disconnected from the phono stage the hum through the speakers still persists and the noise level increases if I touch any part of the tonearm or the earth screw on the phonostage.I am at a loss to know how to resolve this mega annoying issue- not helped by my zero tech knowledge or know how-Thanks for your post and anyone else please offer your thoghts/ possible solutions.

[Analogue man]

You don't say what arm and cartridge you have, some cartridges have a tag across one of the pins to the metal body of the cartridge, if by some chance this has accidentally been connected to the phono preamp hot terminal (rather than the earth terminal then this would cause the symptom's you describe. If I'm wrong I can tell you that hum can be a swine to track down.