Superclock in SL-1210

[ar-t]

Anyway, back to the original issue.........

Guys, I am probably the only person any of you will run into that has experience designing low-jitter oscillators. If sticking a different crystal into a circuit was all it took, anyone could do it. But, it is far more complicated than that.

Most crystals perform about the same, because they are all made about the same. And that is: cheap.

To get any less phase noise (jitter) than you already have, it will cost $$$. You can not, or will not, get a "typical" crystal that will perform any better. Even if you called up someone, like IQD (in your neck of the woods), they are not going to budge unless you start to talk about making thousands. If you do find someone who will make a one-off, without a large minimum, or price tag, what do you think they will sell you?

"Why don't you want a HC-49/s? What is wrong with them? That is what everyone uses these days."

(At this point, you know you are talking to a salesman, and you might as well talk to the wall.)

Just like pretty much everything else, these days, crystals have been relegated to "commodity" status. Which means no one makes their own, as they outsource to Asian suppliers. Which is why they are all cheap, and perform that way.

In fact, I will stick my neck out further, without even seeing what is inside your TT, and go as far as to say if you do get a "new" crystal that it will be worse, than what you have.

Guessing what era that TT was made, I will wager it uses a HC-49 holder. Which is the typical holder used in commercial electronics, back then. They are ok. Biggest flaw is it is a resistance-weld holder. Which is going to limit performance, as it will not be as clean (internally) as one would need, for really good performance.

And you are going to step down, to a HC-49/s.

I am sure there is 1000 things you can do, to improve your TT. Changing the crystal is not one of them.

[WOStantonCS100]

Anyway, back to the original issue.........

Guys, I am probably the only person any of you will run into that has experience designing low-jitter oscillators. If sticking a different crystal into a circuit was all it took, anyone could do it. But, it is far more complicated than that.

Most crystals perform about the same, because they are all made about the same. And that is: cheap.

To get any less phase noise (jitter) than you already have, it will cost $$$. You can not, or will not, get a "typical" crystal that will perform any better. Even if you called up someone, like IQD (in your neck of the woods), they are not going to budge unless you start to talk about making thousands. If you do find someone who will make a one-off, without a large minimum, or price tag, what do you think they will sell you?

"Why don't you want a HC-49/s? What is wrong with them? That is what everyone uses these days."

(At this point, you know you are talking to a salesman, and you might as well talk to the wall.)

Just like pretty much everything else, these days, crystals have been relegated to "commodity" status. Which means no one makes their own, as they outsource to Asian suppliers. Which is why they are all cheap, and perform that way.

In fact, I will stick my neck out further, without even seeing what is inside your TT, and go as far as to say if you do get a "new" crystal that it will be worse, than what you have.

Guessing what era that TT was made, I will wager it uses a HC-49 holder. Which is the typical holder used in commercial electronics, back then. They are ok. Biggest flaw is it is a resistance-weld holder. Which is going to limit performance, as it will not be as clean (internally) as one would need, for really good performance.

And you are going to step down, to a HC-49/s.

I am sure there is 1000 things you can do, to improve your TT. Changing the crystal is not one of them.

If what you say about sourcing crystals is true, then I have a big question for Inspire about their Monarch turntables. They say, "...such as a new
quartz chip of greater spec..." So, either someone has already done what you say only has a slim chance of being possible or the Inspire folks aren't being honest. I would love to know which one it is.

[MartinT]

I am sure there is 1000 things you can do, to improve your TT. Changing the crystal is not one of them.

Thank you Patrick, that's very useful information. The crystal type as far as I can see is a HC49 low profile can.

So, if we assume for the moment that the crystal cannot be improved upon, we are left with two scenarios:

1) Lift the crystal from the PCB and make a temperature controlled environment for it, say between 40-60C.

2) Lift the crystal from the PCB and put it into a better/more stable oscillator circuit.

The question is, will either of these give us lower jitter than the crystal in the AN6680 circuit fed with a very clean power rail?

[Marco]

If what you say about sourcing crystals is true, then I have a big question for Inspire about their Monarch turntables. They say, "...such as a new
quartz chip of greater spec..." So, either someone has already done what you say only has a slim chance of being possible or the Inspire folks aren't being honest. I would love to know which one it is.

Me too, Biff!! Any view on this, Partick?

Here's a pdf of the review where the crystal upgrade is mentioned: http://www.inspirehifi.co.uk/inspire...n12%5B1%5D.pdf

The onboard circuitry is upgraded with high-spec parts such as a new quartz chip of greater spec – taking speed control to even greater heights than previously achieved with past Technics, it is claimed.

???

Marco.

[sq225917]

That's an obvious and demonstrable claim, most simple Xo come in one of two specs, 30ppm or 20ppm, other than that you really would be specifying an uber part in a oven and a decent tcxo is going to cost a lot more than Bob could afford to put in that deck. The simple way to find out is to look at the part currently in the 1210, if it's the 30ppm piece then It can be improved, if it's a 20ppm then it really can't.

I view all such 'marketing' claims with healthy skepticism. I'm with ART on this one.

[Marco]

Sorry, Simon, for the benefit of the non-technical minded, could you please explain (in 'layman' terms) what an "Xo" is, and what "30ppm or 20ppm" are, and what sonic influence each would have?

Also, would the sonic advantages between 30ppm or 20ppm be roughly equipvalent to what a "decent tcxo" would do (and if not, why?) - oh, and while you're at it, what exactly is a "decent tcxo"?

Churz!

Marco.

[sq225917]

20 parts per million: a measure of accuracy. Xo are generally specced for noise and drift. The difference between 20 and 30 ppm will be utterly inaudible, but as technical claims go 20ppm is 'better' than 30.

Xo oscillator
Vcxo voltage controlled.
Tcxo temperature controlled- ie in a regulated oven.

[Paul Hynes]

Pat,

Your comments regarding sourcing crystals, and their use, is helpful. Industry is slowly taking us all down to the lowest common denominator. Fortunately there are still those who are dedicated to making things better.

Perhaps you would care it illuminate us as to why you think there are no regulators capable or regulation up to 100 MHz.

Regards
Paul

[Marco]

Thanks, Simon

Xo are generally specced for noise and drift. The difference between 20 and 30 ppm will be utterly inaudible, but as technical claims go 20ppm is 'better' than 30.

So if that's the case, and as you say likely what Inspire have 'improved' in the new crystal that they're using, it's not going to account for any huge improvement in sound.... Is it? Therefore, whatever is making the Monarch sound so good (as per the reviews), if you are right, obviously isn't the new crystal.

The only way to achieve a genuine upgrade in that area, it would seem, is to have a top-notch bespoke crystal designed, as Partick has outlined. And based on what he's said, that ain't going to happen anytime soon!

What needs to be done, so that we're dealing in facts, not fiction, is for the crystals used in both the Monarch and the Techy to be identified, and that information reported here. Who's up for that job, then?

Marco.

[sq225917]

Marco, the crystal is divided down so far it's likely to make 0.0000000001% difference of the square root of f_ck all. It's a specious claim at best. What we really need is a demo- heads up, back to back. ;-)

So much of the 1210 sound is in the mechanical parts and their mounting.