Oracle Delphi mk1 Quick Restoration

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IslandPink
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#16 Re: Oracle Delphi mk1 Quick Restoration

Unread post by IslandPink »

I don't know enough about suspended vs. non-suspended, but the belt drive ( vs.DD/RD ) makes a big difference.
You can hear a surprising amount of difference on the Hyperspace, in the bass and lower mids, from replacing the normal Nottingham AC motor & belt drive with a rim-drive motor pod. This despite the Hyperspace having a 13kg platter.
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shane
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#17 Re: Oracle Delphi mk1 Quick Restoration

Unread post by shane »

A long time ago I put together an idler drive lash-up which used a Heybrook platter and bearing with the motor and a spare idler wheel from an Akai 4000DS, all mounted on bits of slate, with a home made unipivot made from a bit of scrap titanium tube. What you describe is pretty much what I found. The idler had a solidity and stability to it that really grabbed your attention, but the TT2 did the size, depth and rhythm thing at the expense of definition.
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Cressy Snr
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#18 Re: Oracle Delphi mk1 Quick Restoration

Unread post by Cressy Snr »

I heard the Oracle this morning and to me, it sounded as if the musicians would rather have been somewhere else than playing their instruments. They sounded bored, lethargic and uninterested in what they were supposed to be doing. Few redeeming qualities apart from the size of the image, though even that was diffuse.
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#19 Re: Oracle Delphi mk1 Quick Restoration

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The interesting thing to me is that there are outliers such as the yamaha pf800 and the xerxes in there too. The xerxes is not solid but not suspended either with its top being sat on the three turrets with the decoupler wotsits, and the yamaha is somewhere between the oracle and one of the SME decks. It has the dc motor of the oracle, the three suspension turrets of the oracle (in the same places incidentally) but the sprung part of the chassis hangs below the level where the springs attach to the turrets. Kind of like the SME decks that hang on those o ring things, the majority of the chassis and platter is actually below the balance point.

I still wish i hadnt sold the yamaha. It did not sound much like a fruitbox or a td160 et al, but it wasnt anything like a solid plinth belt drive like a rega either. It was a really really good sounding deck.

The xerxes is the same, it sounds different to the fruitboxes and nothing like a rega.

So why?

I have 2 of what are supposed to be very very good belt drives here, 2 of what i consider to be pretty good direct drives, several lencos plus pauls 301. So have alot of bases covered in terms of making a disc spin
Not all seem to fit into the pigeonholes though
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#20 Re: Oracle Delphi mk1 Quick Restoration

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Id love to get hold of a little accelerometer and see what sort of spectrum of noise is getting into plinths, subchassis and arm boards on some of these decks to see if anything correlates to percieved sound quality
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#21 Re: Oracle Delphi mk1 Quick Restoration

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Year 1 . Social theory and research 101 .

Correlation is not causation.

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Cressy Snr
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#22 Re: Oracle Delphi mk1 Quick Restoration

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But applied to discussion about stereos. The inevitable question has to be, who gives a shite?
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#23 Re: Oracle Delphi mk1 Quick Restoration

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Cressy Snr wrote: Tue Jun 07, 2022 7:06 pm But applied to discussion about stereos. The inevitable question has to be, who gives a shite?
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#24 Re: Oracle Delphi mk1 Quick Restoration

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Well, TBH, I do, otherwise you end up chasing the wrong rabbit down the wrong hole.
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#25 Re: Oracle Delphi mk1 Quick Restoration

Unread post by shane »

Daniel Quinn wrote: Tue Jun 07, 2022 4:55 pm Year 1 . Social theory and research 101 .

Correlation is not causation.

West Wing - ergo proctor hoc post hoc
Brief to the point of opacity. Are you saying that just because we've observed similar effects when comparing suspended belt-drive turntables to non-suspended idler and belt drive designs, the apparent common differences aren't necessarily due to the different design concepts? You may well be right, but it's not an unreasonable basis from which to start investigating exactly what does cause the observed differences. Sadly, a thorough investigation wold involve engineering resources beyond the reach of most, so we have to make do with conjecture.
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#26 Re: Oracle Delphi mk1 Quick Restoration

Unread post by Daniel Quinn »

I was making the point Nick made more succinctly

It seems to me much of explanation in hifi is not worthy and is simply a waste of time .

Another reason for my methodology. Listen and likey or no likey .
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#27 Re: Oracle Delphi mk1 Quick Restoration

Unread post by IslandPink »

I'm lost now. Are you and Nick definitely making the same point ?
Give us an example of how things should be done, in the context of this specific point.
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#28 Re: Oracle Delphi mk1 Quick Restoration

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Given three things. Two of them (A and B) have a characteristic you are interested in, one doesn't (C). Two of them have a design style that distinguishes them (A and B) leaving C without that design style.

We would like to think that the correlation with the design style and the characteristic, means that we could infer that the style caused the characteristic. But we have no way of knowing that is true. There could be another hidden (to us at this time) feature of A and B, that is the cause of common characteristic and it would be fallacious thinking to assume that the correlation of A and B is caused by the style.

We would have to perform additional experiments (preferably after making predictions) to determine if there is actually a causal link and exactly what it is.
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#29 Re: Oracle Delphi mk1 Quick Restoration

Unread post by IslandPink »

Ah yes, but really the A,B & C decks assumption is a simplification of real life, and most of our listening experience, which is likely richer.
Most of us (analogue fans) on here will have heard maybe 12 or 15 decks to a decent extent ( more in the case of Ant and James ) and may have experimented with different drive on the same deck. What you have is a bit of a straw man to illustrate the logic problem.
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#30 Re: Oracle Delphi mk1 Quick Restoration

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I was making no statement other than using a example after you questioned what I meant. Ant presented a set of observations that seemed to contradict conventional wisdom that was all.
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