Rega Planar 6 sagging issues

[Mr Pig]

As with all manufactured / engineered components they have an allowed tolerance. Rega allows a deflection of 1.6mm for the Planar 6.

For a turntable that costs over a grand, excuse me if I don't find that very comforting? At the price, is it really too much to ask that it's flat? Why would it be hard to make it flat?

Clearly some turntables are more bent than that, both from the pictures and the fact that owners have had their decks replaced. So either they did bend over time or they left the factory more than 1.6mm bent. Correct?

 

[DimitryZ]

Is this a tilt of the entire deck from the front to the back?

If so, given Rega's unique choice of position for the three feed (which places a large percentage of the weight on only one foot - the back one), it is entirely normal to expect that the deck will not sit straight on a perfectly straight platform. Rega owners know this and we adjust the shelf accordingly, with the bubble level on the platter...

What's the big deal?

 

[Woodface]

SHF does have a tendency to over react

 

[Mr Pig]

Is this a tilt of the entire deck from the front to the back?

No.

 

[jimmytwos]

The comment of acceptable deflection in the plinth material possibly related to the way its manufactured? I don’t know what specific material is used on a rega plinth but I can imagine when laminated/glued this will have an effect to pre stress the inner layer which when fresh out of production may exhibit some bending upwards? So my own guess is this is what is being referred to? Either way I would just contact rega directly end of.
Mass production of anything has a ratio of tolerance for failure, being that we have no idea of the conditions in which the turntable has been used I can imagine we only have half of the picture.

 

[Robert]

I'm struggling to understand what could sag on a Rega. The whole design ethos is centred on low mass combined with high stiffness. The last thing you would see is anything sagging!

 

[paul darwin]

We build turntables, we export to over 50 International markets, they could be used in temperatures of plus 50 degrees C to minus 50 degrees C, from zero to 95.3% humidity.

We have no control whatsoever over the operating conditions, nor the structural pressures put on them.

However, as a matter of course during our developmental processes we have measured any minute tolerances of the plinth using very sophisticated equipment costing thousands of pounds and found that flexitude of 1.6mm or less (i.e. 0.06" at plinth level) has no effect whatsoever on performance and is therefore considered to be within acceptable manufacturing tolerances and is completely and totally inaudible. Indeed, it is entirely possible that many cartridges could be installed with a greater magnitude of measurable alignment difference giving profoundly different and potentially far worse results.

It's funny but talking to a mate of mine who is a senior engineer at one of the local F1 teams (and a Planar 6 owner co-incidentally) he observed that they would kill to have consistent results of that kind with some of their parts during operational race conditions (i.e. temperature and humidity extremes)

 

[DimitryZ]

We build turntables, we export to over 50 International markets, they could be used in temperatures of plus 50 degrees C to minus 50 degrees C, from zero to 95.3% humidity.

We have no control whatsoever over the operating conditions, nor the structural pressures put on them.

However, as a matter of course during our developmental processes we have measured any minute tolerances of the plinth using very sophisticated equipment costing thousands of pounds and found that flexitude of 1.6% or less (i.e. 0.06" at plinth level) has no effect whatsoever on performance and is therefore considered to be within acceptable manufacturing tolerances and is completely and totally inaudible. Indeed, it is entirely possible that many cartridges could be installed with a greater magnitude of measurable alignment difference giving profoundly different and potentially far worse results.

It's funny but talking to a mate of mine who is a senior engineer at one of the local F1 teams (and a Planar 6 owner co-incidentally) he observed that they would kill to have consistent results of that kind with some of their parts during operational race conditions (i.e. temperature and humidity extremes)

Paul, can you explain to us what exactly is flexing here?

I have owned an old Planar 3 (1990, still in service at a friend's house). I currently own a vintage P9 and recent make P8. None of these decks have plinths that will flex anywhere near 60 mils with standard Earth gravity. One would have to add many pounds (very heavy clamp or puck?) to get this kind of deflection.

The other option is to transport them to Saturn or Jupiter to experience much larger gravity. Do you currently export to other locations in the Solar System or Gallactically?

 

[paul darwin]

I merely used the word flexing as an alternative to sagging as I didn't particularly like the word sagging as it filled my mind with unpalatable thoughts

 

[DimitryZ]

I merely used the word flexing as an alternative to sagging as I didn't particularly like the word sagging as it filled my mind with unpalatable thoughts

Thank you!

I have read a sampling of the tedious and neurotic thread OP referred to. I stopped reading after an aerospace ignoramus opined on the Challenger o-ring failure.

Overall, the "sag" seems like 99.9% non-issue. And if this becomes an issue (greater than 60 mil sag), Rega will rectify.

Technically, choice of foam for the core of a sandwich panel is a set of compromises. For light loading, very low density foams will do the job. Then there are material choice, open or closed cell type, moisture absorbtion, adhesive compatibility, etc. Creep is generally very hard to test for. There are techniques to quantify creep using elevated temperature TMA/DMA testing and extrapolating to the lower service temperature. We have done that for face sheets (skins) in an RF radome application....but it is even more challenging for light foam loaded in shear.

 

[Yank]

Is this a tilt of the entire deck from the front to the back?

Dished. Cupped. Concave. The center lower than the edges.

 

[DimitryZ]

Dished. Cupped. Concave. The center lower than the edges.

The picture in the OP external forum thread seems doctored or photoshopped. In that thread, the complaining party admits that his sag is less than 60 mils and, therefore, doesn't qualify for Rega remediation. Yet the "photo" shows a good 0.125" or more sag - looks like a hammock.

This makes the whole issue very suspicious. Is the complaining party an actual Rega customer?

 

[Mr Pig]

The picture in the OP external forum thread seems doctored or photoshopped.

You wouldn't necessarily have to. If you take the picture at the right angle etc you could easily exaggerate any bend. However, some people have had turntables replaced which, if correct, confirms that there is or was an actual issue.

Overall, the "sag" seems like 99.9% non-issue.

Yes, I think that is the important takeaway.

It doesn't matter what you buy, a car, a TV or a record player. Or how expensive or well made it is. There is always a possibility that something will go wrong with it. If it does, it is the manufacturers fault, they built the thing, so realistically there are only two things you can expect from them.

That they build their products to be as reliable as possible and if they do go wrong they'll be there to sort it out. You have to concede that Rega pass this test with high marks.

Yes, it is a bit crap that people have had bent plinths but context is everything. The thousands more with flat plinths don't post on the internet about it. Happy customers far outweigh the disgruntled ones. Your chances of buying a Rega turntable and having no problems whatsoever are probably in the 99.9% ballpark.

I think it's perfectly fair to flag up and talk about issues like this. However rare, if you get a bad product you don't care that everyone else's ones are fine and I think it's good that manufactures are aware of the implications of quality control breaches. But the bottom line is that a wonky product is always a possibility and it's more likely if you buy a product not built by Rega!

 

[Jono_13]

For balance I have had several Rega products over the years and all have been faultless in build quality.

 

[Del monaco]

For balance I have had several Rega products over the years and all have been faultless in build quality.

Same for me. Rega appear to take their time to get their products right and their after sales service is exceptional. What more do you want from a company? The kind of testing and checking rigour outlined by Paul above is consistent with the care and pride they have for their products.

 

[Jono_13]

To be honest this feels a bit like the fat lad who complained that his phone bent when he sat down with it in his back pocket. Just enjoy the music and give your OCD a rest.

 

[Mr Pig]

To be honest this feels a bit like the fat lad who complained that his phone bent when he sat down with it in his back pocket.

Not really. Not much you could do to bend a plinth through misuse so if some were bent, it's a legitimate complaint.

But if you're dumb enough to buy phones thinner than a cream cracker you deserve what you get! ;0)

 

[Del monaco]

I think it’s a legitimate concern but this has been tested. It could also be checked by Rega. It may be a manufacturing fault and may lie outside of the tolerances. This happens to even the most prestigious manufacturers and In sure it can be checked and sorted.
We had an Audi that failed. They recognised a manufacturing issue. The correction cost £10K and they footed the bill.

 

[Sue Pertwee-Tyr]

I’m confused by the inconsistency in reporting the numbers on this thread. Early on, it was said that a discrepancy (avoiding ‘sag’ for Darwin’s benefit) of 1.6mm was acceptable according to Rega. Paul Darwin himself cites 1.6% or 60 thou’ (0.06”), which seems to have become 60 mill (about 2 1/2 inches) in some people’s heads. I reckon 60 thou’ is probably not too different to 1.6mm, but if you’ve said, or repeated, 60mill(imetres) and not realised how absurd it would be, maybe read it again?

 

[Seanm]

Rega products are great IMO and so is the customer service, on the whole, but I think they do rely too heavily on what, to the average customer, look like generous tolerances. It doesn’t really matter if 1.6mm sag makes no difference to the sound, I’m sure it’s visible and will take a big chunk off the resale value. I had a similar issue with platter wobble on an RP6 and know from experience that the “within tolerance” line marks the exact point where helpful customer service turns into “I’m afraid they’re all like that sir”. They’ll replace it but they’ll make you feel like a fussy fool for insisting.