Ground Hum with Rega RP6, Exact and TT PSU.


Greetings.

Just purchased a Rega RP6, Exact, TTPSU and I am getting a HELL of a hum. I am using an Aragon 47K Phone pre amp. I unplugged the wall wart and the cable which goes from the table and it is still there. I seems to get worse when I turn it on and the tonearm gets close to the center of the arm spindle and it picks up a lot of motor noise. Just sold a 28 year old Linn Axis with a Signet Cartridge and never had this issue with just the normal hiss associated as you turn up the volume. It's not noticeable a lower volumes but it is there during quiet passages and it is extremely annoying. The table sounds way better but the noise is very intrusive and honestly I am disappointed after dropping almost $2000. Thanks in advance
pivetta

Showing 2 responses by les_creative_edge

Hi,

I recall a poster on Youtube with the same hum issue on his RP6 and TTPSU. His solution was to grab a length of wire, careful back out the left side, back screw on the TTPSU and apply the ground wire to the screw then place screw back in place. From such he then grounded out the TTPSU to his ground post on phono preamp and TA DA the hum vanished.

Yes a thin ground wire  does then  stick out from the back of the TTPSU but his problem went away. Rega does not ground the TTPSU and on some cartridges the hum may be an issue. The Youtube video should be below.

https://www.youtube.com/watch?v=CAY2rRsqHLE
crazyeddy,

Roy Gandy of Rega Research has always believed in stiff, rigid and tend to a lighter weight turntable designs. Adjustable VTA will reduce stiffness and rigidity at the tonearm base. All Rega tonearms are grounded. The ground is attached to the LEFT channel neutral lead. This effectively grounds the turntable appropriately.

Rega on almost all of their tone arms are made in ONE piece aluminum extrusions and are by design TRUE/SQUARE and have no need for any azimuth adjustments. Each arm is inspected before installation on any Rega turntables or sold as separate tone arms. Rega sees no need to compromise rigidity of the tone arms with any azimuth adjustments.

Since most Rega buyers are less likely to swap out cartridges there is no real need for a VTA adjustment set up using either a grub screw or a adjust on the fly set up. Rega and 3rd party makers offer various shim type set ups to tweak the VTA to a cartridge that falls out of Rega’s cartridge design for cartridge height. One can buy a VTA adjuster that will do near on the fly VTA too. But Gandy and his engineers fear these reduce rigidity at the arm base.

My new Planar 3 has a Denon DL-110 mounted to the arm and the DL-110 is 2 or so mm taller than the standard Rega choices. It will ride tone arm slightly tail down as a result and it did not make much an issue sound wise to my listening. But I am anal enough to have concocted a DIY shim set up. I gathered 9 small metal flat washers. Stacked them in stacks 3 high, super glued each stack to make 3 shims about 2+mm tall. I drew the arm screws up and fitted these the DIY shims under the RB-330 3 point mount setup then screwed the arm back down its base. TA DA my RB-330 with DL-110 essentially rides parallel to the platter surface. Did it make a big change in sound? Well a bit but no not really too much, but I guess it settled down my anal retentive side on this issue.

It did give me a minor new issue. The arm sits higher now and dust cover closed touches the counter weight. I do wish Rega would make their dust covers a few mm’s taller. But I made a good DIY fix for it too. I found a small credit card sized flat piece of black hard rubber about 3mm thick. I took a craft knife and a steel ruler and made a clean 3mm wide strip cut. I then had a strip that was 3mm thick x 3mm wide x by 8 cm long. Then I cut this strip into FOUR, oh 2cm long pieces. I then carefully super glued the four pieces at each corner of the dust cover base taking care to indent the two rear pieces about 1cm in from the back of the dust cover base so the pieces would not interfere with the opening and closing of the dust cover. Now the dust cover clears the counter weight when closed. You hardly notice these black rubber tabs, they do not scratch the plinth either. Yes, you lose a more air tight seal at the base of the cover but meh its not a big concern. One can use an eraser cut into little tabs as such and glue these to the dust cover base if need be too. But again YES, if Rega would just make their dust covers 3-4mm. taller, there would be no clearance issues in most/all cases.