help with rega RB250 arm rewire

[Guiminha]

Hi there,

Recently I decided to change the external cable of my Rega P3 turntable
and have a separate ground wire. I roughly followed the DIY guide in http://www.hi-fi.com/diy/rega/steps.html but only for the external wiring.
I am still using the original internal wire, so the external cables (including
ground) are now soldered directly to the internal wire (no board in between).

I checked continuity and against short circuits with my multi-meter and
everything looks fine. Then, I remounted the arm, cartridge and plugs
(including ground to the ground spot in the pre-amp). But, when I turn
on the pre-amp, there is this loud static noise as if the ground was not
connect (but it certainly is). I re-checked continuity and also played a
couple of records, and the static noise is always there.

Any clues on what I might have gone wrong? Does the external cable or
the ground cable have to be under strict specifications?

I am attaching a few pictures, so you can have a look.

Thanks in advance for your help,

Guilherme

Guiminha wrote:
Hi there,

Recently I decided to change the external cable of my Rega P3 turntable
and have a separate ground wire. I roughly followed the DIY guide in http://www.hi-fi.com/diy/rega/steps.html but only for the external wiring.
I am still using the original internal wire, so the external cables (including
ground) are now soldered directly to the internal wire (no board in between).

I checked continuity and against short circuits with my multi-meter and
everything looks fine. Then, I remounted the arm, cartridge and plugs
(including ground to the ground spot in the pre-amp). But, when I turn
on the pre-amp, there is this loud static noise as if the ground was not
connect (but it certainly is). I re-checked continuity and also played a
couple of records, and the static noise is always there.

Any clues on what I might have gone wrong? Does the external cable or
the ground cable have to be under strict specifications?

I am attaching a few pictures, so you can have a look.

Thanks in advance for your help,

Guilherme


Your probably best PM 'J7' he does all this, these Rega's are a pain in the arse...Can't see what your trying to acheive just replacing the lead though cos all the wire in the REGA is crap, you also want a dedicated flying ground lead..It's better to wire the lot.



I'm guessing the DNM 'Reson' wire you put on has something to do with it...

[eddie spaghetti]

Yep. j7 is yer man for all tonearm mods.

www.audioorigami.co.uk

[Guiminha]

eddie spaghetti wrote:
Yep. j7 is yer man for all tonearm mods.

http://www.audioorigami.co.uk

Yes, I emalied him already,and he pointed me to this forum, saying that he and other could try to help.

Yes, I am afraid that using the DNM Reson (which was more an experience) is maybe the source of problems.

Regards

G

[j7]

hi and welcome m8ty

there is plenty of guys here that can help...what we need is a little brainstroming session

those pics are great...can you make them any bigger ...my old eyes is struggling



i notice there is not a sheild or braid round the external cables...is that correct?



bw

j7

j7 wrote:

i notice there is not a sheild or braid round the external cables...is that correct?






That what i was aiming at with the Reson, you'll be suprised the amount of people use wire such as the DNM 'Reson', Kimber 'PSB' etc forget that magnetic cartridges need sheilding...

[Guiminha]

ELP FAN wrote:
j7 wrote:

i notice there is not a sheild or braid round the external cables...is that correct?






That what i was aiming at with the Reson, you'll be suprised the amount of people use wire such as the DNM 'Reson', Kimber 'PSB' etc forget that magnetic cartridges need sheilding...
Yes, I am using a DNM Reson, and I guess that has no shielding... So , this might be my trouble... Will try a different external cable and let you know.

G

[j7]

and bigger pictures:pirate:

[Guiminha]

j7 wrote:
and bigger pictures:pirate:
Will have to take them again, since I accidentaly erased those ones... G

j7 wrote:
and bigger pictures:pirate:
J7 i think you got a pic fettish..;)

[j7]

ELP FAN wrote:
j7 wrote:
and bigger pictures:pirate:
J7 i think you got a pic fettish..;)

:zoom:

[Guiminha]

OK. Here go the larger/new pics

I did not tried to change the cable yet.

G

[Guiminha]

another

[Guiminha]

and another.

[Guiminha]

one more

[Guiminha]

and the last one.

[j7]

yea looks like a external cable with a shield is required

[Guiminha]

j7 wrote:
yea looks like a external cable with a shield is required
OK, will try that. Looks like the only left option.

Regarding changin the internal wire: Can I unmount the arm, by separating the arm tube from the base? This can be done by removing the side caps and unscrewing the bearing (?) screws. Will this damage the bearing / rolling / skating mechanism (sorry, dunno the right english words to describe this pieces)? Or the only "right" way to change the internal wire is to fish it through the whole arm?

Thanks a lot for your help

G

Guiminha wrote:
j7 wrote:
yea looks like a external cable with a shield is required
OK, will try that. Looks like the only left option.

Regarding changin the internal wire: Can I unmount the arm, by separating the arm tube from the base? This can be done by removing the side caps and unscrewing the bearing (?) screws. Will this damage the bearing / rolling / skating mechanism (sorry, dunno the right english words to describe this pieces)? Or the only "right" way to change the internal wire is to fish it through the whole arm?

Thanks a lot for your help

G

What ever you do, do not mess with those bearing...

[Guiminha]

ELP FAN wrote:

What ever you do, do not mess with those bearing...
Humm... So you mean I should not unscrew it or unmount the arm tube from the base.
I am afraid I have already done it (OK, not me, but the technician who soldered the cables to me). WHat can have gone wrong? How can I test the arm to chek it?

Regards

G

[j7]

its best you sorted the 1st problem before going to next stage



you are fast making a bad job of a rega rewire...i would be careful here

to be honest with you my friend...a perfectly original rega rb250 sounds better than a home job rewire...

as you will have to dothe job atleast 40 or 50 to become confident with your expected result...at best you can sell the arm on ebay if its not perfect

rebuilding the bearings to the correct value is not easy...requires a fine touch...esp as the bearings can become infected from the rega bearing locktight


let us know how u get on



best wishes

j7

[tangen]

Guiminha wrote:
OK. Here go the larger/new pics

I did not tried to change the cable yet.

G

Hi,

try this link: http://www.aqvox.de/REGA_250_300_Tonearm-mod-humm-free-remove-signal-groundrega_mod.html
and see if this rearrangment of ground wire will solve the problem.

Best,
Jan Ove

[eddie spaghetti]

Welcome to the forum Jan :welcome:

[j7]

hi jan

nice pictures in that link thank you

and welcome to the forum

best wishes
j7