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Micromega Stage 5 and Stage 3 compared...

i had a stage5 and loved it......except for the mech that suffered the 'grease' issue. Ended up skipping it as I couldn't find a replacement mech anywhere and no amount of silicon spray would fix it.
 
i had a stage5 and loved it......except for the mech that suffered the 'grease' issue. Ended up skipping it as I couldn't find a replacement mech anywhere and no amount of silicon spray would fix it.

Holy shit - shame, the mechs are still readily available...and fixing the grease issue is entirely doable DIY (strip & clean) anyhow.

Thanks Martin & Simon. I'll get the scope out, but not for this - I really need to look into the CDI fault...procrastination and diversions over for now I think :)
 
I stripped out the mech and servo board tonight, just to photo document it - plus I wanted to order a spare laser mech for it before they get hard to find (cost of cdm9/44 mechs have increased >400% in last 7 or 8 years, I just paid €100 for one!), and wanted to confirm type ( it's a CDM 12.4/05).

Need to check data sheets, not sure why it has dual tda7073at chips yet, but again it all looks well implemented.

Richard


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I wish :) - bit like Naim CDPs in that respect. That's why I'm taking so many photos! All you can do is check datasheets of main chips and then trace areas of interest.

Tda7073s just do laser focus, sled and spin drive services I think.

I'd love to see some photos of the dac/op board of the stage 6 if you fancy popping cover off - it's hard to rely on some of the images Google throws up.
 
Your photos are great, Richard. I was going to sell my Stage 4, which I've had from new and really enjoyed. Mine got sorted out during the 2 year warranty and hasn't missed a beat since, although it hasn't been used much for the last 2/3 years.

I can't help wandering what similar changes to my machine would result in?
 
To be fair, I've not really modified anything yet except replacing the 4 main smoothing caps to the audio supplies & fitting the snubber across AC winding of same. I went stupidly high with 2 of the smoothers as the board had spare holes for the larger form fact, I've never seen a confirmed stage 6 dac/audio PCB and, well, it would have been rude not to :)

It sounds good - if aural memory is to be trusted better than a recapped & schottky rectifier diode replaced Marantz CD60, but not as good as my CDI with Flea.

I will focus on fixing my CDI now, and have plans for a Flea and dedicated 7220 supply on the CD60 - I come back to the Micromega after that, probably with a Flea too & some output op amp changes.

Richard
 
Bringing this back to life - I never further modified the stage 5, it's kind of a standard to me I listen to every now and then to confirm the players I have properly modified are on the right track.

I've been interested in a stage 3 or 6 for a while (better PSUs for each channel compared to 2 or 5, not really investigated the rest yet) - I just scored a cheap stage 3 - need to fix the obvious faulty laser and sled mech, but should be fairly straightforward to bring back to life. Going to do the same initial PSU mods and see where it takes me :)

So far it is the best player I never modified properly (I added a snubber and upped smoothing capacitance considerably to the stage 5, stopped there).

Richard
 
Richard,

I'd very much appreciate any advice you've got for me on sorting out my Stage 4. I sold it about a year ago, but the courier chucked it about so much, it wouldn't play CDs on arrival. There use to be loads of info on sorting out Micromega Stages on the net, but it's all disappeared.

Can't see anything obvious wrong myself.

Regards,
Graeme
 
What are the symptoms? Most normal issues are related to the relatively crappy 12.4 Philips mechanism, so not reading discs or skipping or tray not working.
 
Got to look at the Stage 3 today - the laser has already been replaced once, and a bit of a bodge job IMO, plus the disc tray belt was kaput. I stripped it, replaced belt and re-did all the 12.4/05 wiring (after confirming correctness of wiring [replacement mech had a different connector on it I guess, so a transplant was done] based on my working Stage 5 which I stripped the mech from). Laser tries to read (up/down and moving outwards a bit to try a 2nd time), but disc doesn't spin. Tried the Stage 5 mech, and bang it works. So need to dig a little deeper into the faulty mech - surprising that a replacement mech is also giving problems.

I also compared the stage 3 and 5 (I've never seen internals of a 6 before) - history suggests Stages 1-3 were first versions of players, and then Stages 4-6 pretty much replicated them but with a power switch. I'd say that is false. Stage 5 DAC board says it is a stage 5 or 6 DAC. The Stage 3 states only stage 3 & has 2 transformers instead of one on the 5, plus about double the regulated stages. Implementation quality is of the same standard as the Stage 5. Even the servo board is different - again, more regulators and larger board.

One thing that is better on the later models is the casework - glued front panel and disc tray aluminium panels on early models (starting to fail), bolted on the Stage 5. Rubber grommets to decouple mech from chassis on 5, not there on 3. However Stage 3 casework is damped with bitchumen, Stage 5 not.

If I had to guess, Micromega sacrificed ultimate sonic quality with better cosmetic quality. Shame.

Full photos below. How does it sound? Better than my Woodside CD3 TDA1541A player with Flea! I kind of understand why Naim chose this as a replacement when stocks of the TDA1541 dried up.

It's been playing for 5 hours now, and I'm hearing things I never heard before - I even swapped back to the Woodside when I heard a bumble bee at start of track 2 of Lamb 5 on the Stage 3 that I'd never heard before. I heard it on Woodside as well but at a lower level, but had never noticed it before! It is a little uncouth compared to the Woodside, the edges of notes are blurred, but I assume that is the Flea on the Woodside.

Once I get a working replacement laser for the 3, I'll sell the 5 I think. Then I can play with a Flea in the 3 :) Reliable sources of Philips 12.4/05 mechs anyone?

Richard

Photos

Stage 5 DAC board;
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Stage 5 servo PCB;
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Stage 3 DAC;
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Look at the difference :)
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Stage 3 servo PCB;
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Side by side;
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Bodged Stage 3 laser mech wiring;
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Slightly better rewire (shame, given mech is faulty :));
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Making remarkably sweet sounds;
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OK, all that glitters is not gold - the stage 3 throws out an image like a turntable, but on the negative side the edges of notes are annoyingly edgy. Need to wait and see it this is just caps reforming (no idea when it was last played), needs a recap, or is because it just has stock clock.

It has much potential, but so far unrealized :)
 
Richard yhe four replaced the one, the five replaced the two and the six the three. I have a three with suprrreg and trichord clock upgrade as well as sprinklings of black gates. I love it. The display and lights are sublime.
 
Hey Simon - yep, they're sublime. But 3 does not equal 6 I think. This 3 is special at least...
 
Just researched a bit - as far I can tell the stage 5 and 6 players share the same DAC/audio board, with an AC feed from the transformer on the servo/PSU board. There maybe a slightly different circuit used between the 2 - there are limited photos available, but one shows an extra potted block fitted to a 6 that my 5 does not have.

I comparison, the 3 has 2 additional transformers on the dac/audio board, each with 2 secondary windings. I assume this is used for +/- for each channel, but have not confirmed yet.

Going to order a replacement 12.4/05 from Donberg in the hope they are a little better than the low quality crap available via eBay. But I also have an original one from a Primare player that is pending a strip and clean & relube...including carefully trying to remove the laser lens without breaking the coil wires, and cleaning all the inside optics too (there's a few reports of this restoring the 12.4 to operation).

Richard
 
I just checked again - I think the additional block on the stage 6 dac board is a better clock :)
 
What are the symptoms? Most normal issues are related to the relatively crappy 12.4 Philips mechanism, so not reading discs or skipping or tray not working.
I forgot what the symptoms now were, so had to dig it out and power it up to remind myself.

Prior to shipping, it was fine. After the courier kicked it around (Interparcel who I no longer recommend), the draw mechanism sticks on both opening and closing. However, it can be helped to open and close with a little gentle persuasion, but won't/can't read the disc index after the disc is loaded, resulting in 'no disc' being displayed. The disc doesn't spin up.

I dismantled the transport mechanism hoping to see something obvious, but didn't. Behaved in just the same way upon reassembly.
 


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