Ariston RD11 wow/ speed modulation

snap, crackle and pop
jspeshmusic
junior member
junior member
Posts: 11
Joined: 23 Jan 2016 17:30

Ariston RD11 wow/ speed modulation

Post by jspeshmusic » 23 Jan 2016 19:29

Difficult to say if this is consistent to a specific point in the rotation, but my RD11 seems to me modulating in speed somewhat. The motor is dead quiet... Everything is dead quiet, and the belt seems to be in excellent condition and tight. Maybe there is something I could check mechanically or electronically? Sort of takes away from the whole experience. Appreciate it! [-o<

steve195527
long player
long player
Great Britain
Posts: 1346
Joined: 05 Jun 2010 01:35
Location: Near Manchester

Re: Ariston RD11 wow/ speed modulation

Post by steve195527 » 23 Jan 2016 21:53

if this has done it since it was new or since you acquired it then it could be caused by the platter being slightly out of balance which can cause the subchassis/arm/platter to rock slightly on the suspension as it rotates,which can cause a bit of wow

Alec124c41
vinyl engineer
vinyl engineer
Canada
Posts: 22724
Joined: 28 Oct 2002 04:24
Location: North of Toronto, Canada

Re: Ariston RD11 wow/ speed modulation

Post by Alec124c41 » 23 Jan 2016 22:57

Before you do anything to the turntable, watch the cartridge playing. If it is moving side to side, this is indicative of a record that has been pressed slightly off-center. Movement of more than a millimeter bugs me, but I listen to more classical and jazz music than rock.

Cheers,
Alec

jspeshmusic
junior member
junior member
Posts: 11
Joined: 23 Jan 2016 17:30

Re: Ariston RD11 wow/ speed modulation

Post by jspeshmusic » 23 Jan 2016 23:14

Yes the side to side motion does occur with some albums but I'm no necessarily convinced that it is the cause of the wow though I'm sure that will contribute to a degree. My tastes are pretty broad, noisy punk or metal to the purely acoustic jazz or classical and it seems to really stick out on any sustained notes or sounds. I feel like steve195527 may be on to something. I want to take a look at the part of the platter that comes into contact with the belt too in case it's dirty.

steve195527
long player
long player
Great Britain
Posts: 1346
Joined: 05 Jun 2010 01:35
Location: Near Manchester

Re: Ariston RD11 wow/ speed modulation

Post by steve195527 » 24 Jan 2016 02:19

if you have had the deck a while and it has only started doing it,it is unlikely to be what I suggested,only if it has done it from when you got it,it is likely to be,platters don't "go out of balance"(unless dropped or damaged in some way)they are either in balance or out of balance when made

jives11
long player
long player
Posts: 3016
Joined: 25 Oct 2011 13:52

Re: Ariston RD11 wow/ speed modulation

Post by jives11 » 24 Jan 2016 10:11

The trouble with wow & flutter is that once you hear it, you can't unhear it, even when its actually on the recording (does happen) or an effect the artist is going for (also happens sometimes).

Wear does occur in the main bearing and in the motor. Sometimes cleaning the main bearing and re-lubrucating, and a single drop of oil on the blade of a screw driver touched against the motor spindle between motor body and pulley, might make all the difference. Has it had any servicing since new ?

is the plinth and platter level with a spirit level ? You can get small plastic ones cheaply, which are light enough not to deflect the thing you are measuring

steve195527
long player
long player
Great Britain
Posts: 1346
Joined: 05 Jun 2010 01:35
Location: Near Manchester

Re: Ariston RD11 wow/ speed modulation

Post by steve195527 » 24 Jan 2016 12:18

jives11 wrote:The trouble with wow & flutter is that once you hear it, you can't unhear it, even when its actually on the recording (does happen) or an effect the artist is going for (also happens sometimes).

Wear does occur in the main bearing and in the motor. Sometimes cleaning the main bearing and re-lubrucating, and a single drop of oil on the blade of a screw driver touched against the motor spindle between motor body and pulley, might make all the difference. Has it had any servicing since new ?

is the plinth and platter level with a spirit level ? You can get small plastic ones cheaply, which are light enough not to deflect the thing you are measuring
you're dead right about being hard to un-hear things once you have convinced your self of anything amiss, not just wow and flutter

jspeshmusic
junior member
junior member
Posts: 11
Joined: 23 Jan 2016 17:30

Re: Ariston RD11 wow/ speed modulation

Post by jspeshmusic » 24 Jan 2016 17:56

Thanks Jives, I'll check and attempt to re-lube the main bearing, and was told that the motors on these tables were best to be left alone since they are pretty finely tuned in the factory, but I cant see a drop of oil on the motor spindle hurting anything.

The deck is fairly new to me but it always had the wow symptom as long as I've had it set up (which, btw I've noticed in recordings which I'm very familiar with and some new as well). The tone arm deck and the platter do seem to be not perfectly flush, though I have my tone arm pretty perfectly level with the top of the platter, which is level to gravity.

I'm sure it's been serviced since new, it has some Linn parts in it. I think the sub platter might be linn (the part with the bearing thats held up by the spring , pretty sure that's the sub platter.)

steve195527
long player
long player
Great Britain
Posts: 1346
Joined: 05 Jun 2010 01:35
Location: Near Manchester

Re: Ariston RD11 wow/ speed modulation

Post by steve195527 » 24 Jan 2016 22:44

what model is it,the rd11,rd11s or one of the other rd11 models,can you post a pic?if it's one of the very early rd11's with a 2 button on/off arrangement and full length black armboard that is actually a linn lp12,before it was called the lp12!

jspeshmusic
junior member
junior member
Posts: 11
Joined: 23 Jan 2016 17:30

Re: Ariston RD11 wow/ speed modulation

Post by jspeshmusic » 25 Jan 2016 02:55

it's one button on/off and the arm board is full length

jspeshmusic
junior member
junior member
Posts: 11
Joined: 23 Jan 2016 17:30

Re: Ariston RD11 wow/ speed modulation

Post by jspeshmusic » 25 Jan 2016 03:04

garbage iPhone photo but whatcha gonna do!
Attachments
d1971c79-fbb0-4f5b-b439-90608880e7cf.jpg
(80.69 KiB) Downloaded 483 times

Alec124c41
vinyl engineer
vinyl engineer
Canada
Posts: 22724
Joined: 28 Oct 2002 04:24
Location: North of Toronto, Canada

Re: Ariston RD11 wow/ speed modulation

Post by Alec124c41 » 25 Jan 2016 15:54

What is the period of the speed variation?
If it is fast, take the platter and belt off, and hold a pencil horizontally, so that it just touches the crown of the pulley, where the belt rides. With the motor on, you should feel no vibration.
If you do feel vibration, the motor shaft has been slightly bent. The pencil will mark the high side.

Cheers,
Alec

jspeshmusic
junior member
junior member
Posts: 11
Joined: 23 Jan 2016 17:30

Re: Ariston RD11 wow/ speed modulation

Post by jspeshmusic » 25 Jan 2016 15:56

ok ill try that today, and I'll be back with some results

jspeshmusic
junior member
junior member
Posts: 11
Joined: 23 Jan 2016 17:30

Re: Ariston RD11 wow/ speed modulation

Post by jspeshmusic » 25 Jan 2016 17:00

Seems to me that is is ever so slightly out (the spindle that the belt runs on motor).

jives11
long player
long player
Posts: 3016
Joined: 25 Oct 2011 13:52

Re: Ariston RD11 wow/ speed modulation

Post by jives11 » 25 Jan 2016 17:27

I've always been a little sceptical that the motor shaft could become bent ? Is it not more likely that the collar bearing of the motor, through which the motor spindle passes, becomes worn with friction over time, allowing some play and hence slight oscillation ? Possibly a drop of oil (a single drop delivered by a probe or screw driver head ) might fill the gap ?

Post Reply