Compatibility between players/recorders

[RichardUK]

Hi everyone - long time MD user here but new to the forum

I rarely have any problems with MD as I love the format, but lately I have noticed that discs recorded on one machine skip quite badly when played back on another. Is this something any of you have experienced before?

[sfbp]

Most likely one of them is out of alignment.

What are the two models in question?

[RichardUK]

Recorded on a Grundig deck and played back on two Sony decks (a 500 series and 700 series) and both Sony decks skipped. Other discs recorded on the Grundig played back OK on the Sony decks, so maybe it's a fault with certain discs.

[sfbp]

Still you give me no model numbers.....

The only reasonable way to find out is to start by making some disks on the Sony(s) and trying to play them on the Grundig.

Sony's - Jim (here on forums) and I can give you some pointers for. Grundig you may be out of luck - no experience even if the relevant manual is available.

Typically what you describe happens because someone is making "borderline" disks. It's rare on decks (I assume you mean the large objects that sit on a counter, sometimes newcomers here breeze talking about decks and we find they mean portables - hence my quibble about numbers). However the read power is much more critical on a deck (it's only 1/10 of the write power) and if you don't get the adjustment perfect you are SOL.

[RichardUK]

Grundig MDC65, Sony JE510 and JE780.

You're right - I need to do some testing between decks.

I just thought I'd see if it was something where people would say 'yeah that happens a lot' before I get into it more.

What you say 'if you don't get the adjustment right' do you mean if Grundig/Sony didn't get it right, or do you mean something I might have done wrongt?

[sfbp]

Neither.

The laser power on decks can and often does go "off" over time. Traditionally people threw up their hands and had the head replaced. Even my friend Jim; as when this starts to happen, the head is often either dead or dying.

But you would be surprised to learn that often a simple adjustment is all it takes. Unfortunately, the right tools are needed, including a Laser Power Meter (which I now have and he doesn't).

And to answer your question about disks, I (and others) have noticed that disks with very transparent covers/casings (the TDK Gold and Silver come to mind) sometimes give problems where other disks do not. This is probably the so-called "stray light adjustment" if you can find it for your particular model (I only looked at this for the portable HiMD player RH910, to be honest).

Stephen

[RichardUK]

Hey Stephen thanks for the help and info.

I think I'll have a good sort through all my discs and try to assess whether some are better than others.

I'll also maybe assign each disk to a certain deck, just to avoid the problem that way also and I can configure my various systems so that I've no need to use the same disc on more than one deck.

[sfbp]

That will quickly get you around the present problem (maybe) BUT it is almost certainly a sign that one of the decks is dying (at least without attention).

The whole laser thingy is, as you know, a nifty servo (feedback) mechanism. So once it starts to stray, bad things usually follow, as stuff overheats and finally blows. I suggest you talk to Jim if you can narrow the problem down to one of the three machines.

[jim.hoggarth]

Hi all. The first item to check off the list is the discs themselves. I often find this problem is down to one machine not liking a particularly dusty or scratched disc, and yet others accept the disc fine. Try opening the flap of a disc which fails on the Sony and inspect it for grime or scratches - a small screwdriver or even a toothpick pushed against the plastic lever between the two halves of the disc casing and the metal or plastic shutter will easily slide open (it's easier to do than describe).

The disc surface on both sides should be an immaculate unmarked mirror finish. Dust isn't too much of a problem, but scratches spell disaster. The recorder will try and map out any bad track sectors, but using scratched discs is not a good idea. You also have to ask how it got scratched in the first place - usually it is grit stuck to the recording head, or the had is physically damaged.

If the discs seem ok, then you need to start thinking the Grundig write laser is on the way out, or the overwrite head is dirty, or the head drive electronics/power supply is bad. Or it could be a fault in the servo system, as Stephen has suggested.

Jim

[NickyJay]

I read somewhere that units made by non-Sony companies will work poorly when played back on Sony machines and vice versa. Some of the manufacturers like Sharp and Panasonic stated that they used different Atrac chips based on their own algorithms and technologies. I think this is why Sharp units sound better to some people. Who knows, your Grundig may also use its own unique Atrac encoder/decoder.

[bluecrab]

I definitely used to get mixed results between my Pioneer MJ-D508 MD deck and Sony decks. Pioneer did have their own version of ATRAC, IIRC.

[NickyJay]

I definitely used to get mixed results between my Pioneer MJ-D508 MD deck and Sony decks. Pioneer did have their own version of ATRAC, IIRC.

Ah was it the 'legato link' conversion? I remember these Pioneer decks now. Now I understand why they go for such high prices on ebay.

[RichardUK]

Thanks everyone for the input. Hopefully soon I'll make time for an extensive testing session to see if I can identify a clearer pattern here.