Grizzly Posted August 13, 2017 Share Posted August 13, 2017 I recently took a punt on a Vimak DT800 in unknown operating condition. It has turned out to be a little bit of a win as it does play beautifully, though the output from the left channel seems to be at a lower level than the right. The only other real issue is a stripped drive gear for the tray which is a simple fix. I will be getting it looked over by someone smarter than I but would love to get hold of some schematics (assuming they will be invaluable to the tech), an owners manual and (long shot) a remote control. Anyone able to to offer any assistance at all in these regards? Link to comment Share on other sites More sharing options...
Guest Posted August 15, 2017 Share Posted August 15, 2017 Nothing at all? I have discovered that there are 3 status LEDs inside the unit. One seems to be for power and the other 2 for analogue output. If a digital output is engaged on the front panel, the 2 output LEDs go out. Strangely sometimes when the unit is powered up the output LEDs flicker rather than glow, and there is no analogue output. The old "switch it off and back on again" seems to eventually work, but obviously there is an issue to investigate somehow. Interestingly the channel imbalance seems to have rectified itself..... I like to think I am format agnostic, but this is the most engaging digital I've ever heard, in some ways out shining a PS Audio Direct Stream Jr. a couple of nights ago! Link to comment Share on other sites More sharing options...
georgehifi Posted August 16, 2017 Share Posted August 16, 2017 (edited) 16 hours ago, Grizzly said: I have discovered that there are 3 status LEDs inside the unit. One seems to be for power and the other 2 for analogue output. If a digital output is engaged on the front panel, the 2 output LEDs go out. Strangely sometimes when the unit is powered up the output LEDs flicker rather than glow, and there is no analogue output. The old "switch it off and back on again" seems to eventually work, but obviously there is an issue to investigate somehow LED's are sometimes used as circuit diodes, I looked at your pics and could not see any in the output stage. 16 hours ago, Grizzly said: but this is the most engaging digital I've ever heard, in some ways out shining a PS Audio Direct Stream Jr. a couple of nights ago! That's because it's PCM1702 R2R multibit with HDCD, not Delta Sigma. Cheers George Edited August 16, 2017 by georgehifi Link to comment Share on other sites More sharing options...
Guest Posted August 16, 2017 Share Posted August 16, 2017 The LEDs seem to be labelled "AES LOCK" and "PLL LOCK".Ive taken pics of most of the larger chips. Cant see a PCM1702 marking on any. Certainly interested if any make sense to you@georgehifiSent from my SM-G930F using Tapatalk Link to comment Share on other sites More sharing options...
georgehifi Posted August 16, 2017 Share Posted August 16, 2017 (edited) They have nothing to do with the analogue output as you mentioned in your first post, those two are phase lock loop and aes. And as I explained in your other thread on this unit, you have a PMD100 HDCD chip and PCM1704 dac convertors but they have been sanded and re-badged by Vimak, good luck on getting a circuit diagram if they do this sort of hiding of component identities. http://uploads.tapatalk-cdn.com/20170810/49e39c23ec344caac69773e93f617524.jpg Cheers George Edited August 16, 2017 by georgehifi Link to comment Share on other sites More sharing options...
Guest Posted August 16, 2017 Share Posted August 16, 2017 1 hour ago, georgehifi said: They have nothing to do with the analogue output as you mentioned in your first post, those two are phase lock loop and aes. And as I explained in your other thread on this unit, you have a PMD100 HDCD chip and PCM1704 dac convertors but they have been sanded and re-badged by Vimak, good luck on getting a circuit diagram if they do this sort of hiding of component identities. http://uploads.tapatalk-cdn.com/20170810/49e39c23ec344caac69773e93f617524.jpg Cheers George With some skilful internetting I have found a couple of places (both in Italy) that have worked on Vimak gear in the past so with luck one of them may have some useful information that they may be willing to share. Fingers crossed! A minor note on the sound- Every Wed night a good mate comes over to share new music and banter. We played this and some vinyl and noticed a distinct overlap in tone between the 2, something that has never before been apparent with other CD players. Link to comment Share on other sites More sharing options...
Misternavi Posted August 16, 2017 Share Posted August 16, 2017 14 minutes ago, Grizzly said: With some skilful internetting I have found a couple of places (both in Italy) that have worked on Vimak gear in the past so with luck one of them may have some useful information that they may be willing to share. Fingers crossed! A minor note on the sound- Every Wed night a good mate comes over to share new music and banter. We played this and some vinyl and noticed a distinct overlap in tone between the 2, something that has never before been apparent with other CD players. I remember the Vimak DAC many years ago. wasn't cheap but built like a tank. You did well. Link to comment Share on other sites More sharing options...
Guest Posted February 7, 2019 Share Posted February 7, 2019 (edited) A revisit to an old topic. Given that my limited research results gave an overwhelming response of "wonderful, but temperamental and fragile" I decided to have it thoroughly gone over by @johnmath. The brief- "Take as long as you need and sort out any issues you may find". John worked on the beast sporadically when time permitted and discovered someone had replaced many of the original caps with the cheapest rubbish possible so this was duly rectified as well as a number of IC units which needed changing and many dry solder joints. 16 months, 52 caps, 4 ICs, one battery and a drive wheel later I finally got it back last night after John very conveniently brought it over from KI on one of his regular trips. It's worth noting that John was flying completely blind on this one as there are no schematics available, and none of my enquiries yielded even a response, let alone any useful information. I'm still hopeful that someone may have a manual somewhere that I can copy to learn the mysterious functions and how they all work. Oddly when I plugged it in last night there was zero analogue output. John mentioned that it can take a short while to "stabilise", and we did have a digital signal coming out (even so, I was very anxious!) so I left it in standby overnight to find that we did indeed have music this morning. YAY!! I'll experiment with how long this stabilisation takes as the power draw even in standby seems a bit (power supply side is still quite warm). Still, if it sounds as good as I remember, that can be forgiven. Hopefully there will be a chance tonight or tomorrow for a serious sit down session. Edited February 7, 2019 by Grizzly 1 Link to comment Share on other sites More sharing options...
Grimmie Posted February 11, 2019 Share Posted February 11, 2019 So how did things turn out @Grizzly did all your patience pay-off in the end? or are you all bitter and twisted that such a drawn out drama has left you underwhelmed? Link to comment Share on other sites More sharing options...
Guest Posted February 11, 2019 Share Posted February 11, 2019 So how did things turn out [mention=106714]Grizzly[/mention] did all your patience pay-off in the end? or are you all bitter and twisted that such a drawn out drama has left you underwhelmed?It was never a drawn out drama, I stayed in touch with John and told him at every stage to take his time and fit it around other work. Initially I was a little underwhelmed but after being powered up for a good few days the sound seems to have become more fluid and more detailed as well. I suspect there's still improvement to be had with more time but I'm more than happy with the outcome, and not really missing the borrowed Naim CDX2 I had previously. So yes, patience paid off[emoji7] 1 Link to comment Share on other sites More sharing options...
Guest Posted February 13, 2019 Share Posted February 13, 2019 So it seems my glowing report was premature. After a week of great sounds I fired it up last night to hear a light buzzy crackle through the speakers. The Vimak read a disc and began playing but the crackle persisted. Then she stopped playing and all of the indicator lights lit up with a corresponding lack of response to any function. Since then the same christmas tree event seems to take place randomly within 1 second and 15 minutes of playing. Bum poo bugger.John has suggested a few things to try inside which I may have a crack at this weekend, but I'm not keen on investing any further into it without a guaranteed outcome. Perhaps it does need to be shelved or passed on to someone cluey and keen for a real challenge! Link to comment Share on other sites More sharing options...
rantan Posted February 13, 2019 Share Posted February 13, 2019 YES. I can confirm all of the above. It's a damn shame though and it should happen to someone I dislike rather than a great mate Link to comment Share on other sites More sharing options...
audiofeline Posted March 18, 2019 Share Posted March 18, 2019 FYI, some info on Vimak CD patents: http://www.freepatentsonline.com/5289439.html https://patents.justia.com/assignee/vimak Link to comment Share on other sites More sharing options...
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