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Author Topic: Problem with Ernemann 15 Soundhead James Whittle Film Handler Posts: 8 From: denbury, devon, uk Registered: Jul 2008 posted 07-19-2008 02:48 PM                     Hi Im new to this forum but have been a projectionist for around 22 years but I have recently come across a problem that baffles me and I would be really interested if anyone can offer any advice. 2 years ago I took over as projectionist at a cinema that runs 2 x Ernemann 15s on changeovers. the sound was never great here on film (wonderful on digital cinema). We were using a CP500. The CP500 finally died a few months ago and we bought a shiny new CP650 which was fitted by Sound Associates. They set up the unit and we did the B Chain set up. Digital cinema sounded great still but 35mm just sounded wrong, there was some distortion to the sound which seemed to be in the background and worse in the quiet parts of the film. The Sound Associates engineer put a pink noise loop on both projectors and the curve on the scope was spot on but was 'pulsing up and down' The allignment of the lasers looked ok and we also had dolby tone set fine. Knowing that there was not a fault in the CP650 we asked the ernemann engineer to come and have a look. He said that the soundheads were 'damaged' but would not elaborate and we would have to send them to Ernemann in Germany to be reset. Not convinced of this explantion we did some tests ourselves and found that both soundheads had become 'microphonic' we could hear the projectors running through the speakers and if you tpped gently on the soundhead we can hear this aslo. We emailed Ernemann and told them what we had found and duly returned the soundheads to Germany which cost a hell of a lot of money. Last week the Ernemann engineer arrived and refitted the soundheads. He said that Ernemann had found dust ingress in the sound drum bearings and had replaced the light pipes, lasers, and some rollers as well as the offending bearings. When we fitted the soundheads the problem still exisited and was worse if anything. the soundheads were not alligned and failed a buzz track test. We have done the obvoius things like replacing the cables and checking for dry solder joints but this has not resolved the problem. The Ernemann engineer seems baffled but says that soundheads cannot be repaired on the projector they must go back to the factory but Ernemann themselves say that microphony from the soundhead is normal and the pulsing seen on the scope is acceptable and we 'must not be using them correctly!' We now have a very large bill heading our way for this repair and the engineers time. When running properly these projectors give good picture and sound but now they are 10 years old thay seem to be suffering a hell of a lot of problems, given we only run 1 show per day. We have also had faliures of the take up friction drive cards, take up bearings and turret problems as well as very unstable current from the rectifiers. Can anyone please shed any light on this subjct or has anyone else had this problem Any help and advice would be really appreciated before I loose all my hair! Cheers  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-19-2008 03:33 PM                     Microphonics can often be traced to grounding issues  |  IP: Logged James Whittle Film Handler Posts: 8 From: denbury, devon, uk Registered: Jul 2008 posted 07-19-2008 03:37 PM                     Hi Gordon Thanks for your reply. We already tried ground (and removing it) Interestingly enough, Ernemann specs for connecting the soundhead to a Dolby processor differ from Dolby's own reccommendation, just to make sure, we tried both versions. We find it very hard to get any support or feedback from Ernemann  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 07-19-2008 10:10 PM                        Kill the laser; go red LED/Kelmar, if they make one. You will then have a "normal" soundhead. Louis  |  IP: Logged Richard Fowler Film God Posts: 2392 From: Ft. Lauderdale, FL, USA Registered: Jun 2001 posted 07-20-2008 01:43 AM                     Some Ernemann 15 have to deal with a pre-amp card which have had issues. Bad soundhead bearings and worn pre-sound drum damping roller will create noise. Reverse scan LED a la Kelmar or other would require some machine work on the sound drum to allow a heat sink for the LED.  |  IP: Logged James Whittle Film Handler Posts: 8 From: denbury, devon, uk Registered: Jul 2008 posted 07-20-2008 04:26 AM                     thanks for the replies guys. A normal soundhead would be great! in fact a 'normal' projector would be even better. Our model of Ernemann are the earlier versions which do not have a pre amp card, its straight from that well know high quality audio connector (the SCART!!!) to the Dolby CP650 I am convienced that this noise is mechanical in origin rather than electronic. I cant beleieve the bearings had worn out so fast in both soundheads. Not to mention that this noise is so clear, if you stand next to a stage speaker you can even hear the 'clicking' of the intermittent. I dont know if its possible to convert to LED on the Ernemann. With the current (and previous) lack of help from Ernemann we are seriously looking at a pair of Vic 5s or FP30s. I think the main problem is that there are so very few Ernemanns in the UK. Our sound fault is all the more strange given that it exisists on both projectors, could it be a design fault?  |  IP: Logged Pete Naples Phenomenal Film Handler Posts: 1565 From: Dunfermline, Scotland Registered: Feb 2001 posted 07-20-2008 06:18 AM                     I look after a lot of Ernemanns, it is not true to say there are few in the UK. There's a chain of cinemas in Northern Ireland who use them exclusively. Probably into the 100's or Ernemann 15 on the circuit by now, many of them connected to CP650s with zero issues. I'm amazed you say you've had a lack of help from Ernemann, I have always found both Ernemann Germany and their UK agent to be among the most helpful manufacturers in the business, certainly exceeding Strong and Cinemecannica in my experience I wonder, you say the soundheads were not aligned correctly in terms of buzz track. I am not trying to teach anyones granny to suck eggs here, but it's not possible that the transit clamps are still on the drum are they? They don't stop the drum from rotating, but will drag it and make the head run out of alignment, I fond that out after a head scratching session on an installation. Of all the Ernemann 15s I've looked at, I have never touched the factory soundhead alignment, as I could always plainly see I could not better it, which makes your problem even more strange to me. I think your machines will have a pre-amp card, I've never seen a 15 with the Raytheon sound head that doesn't, it may not have any outwardly visible controls or indicators though. Usually the pre-amp card is accessible through the back of the rack bay.  |  IP: Logged James Whittle Film Handler Posts: 8 From: denbury, devon, uk Registered: Jul 2008 posted 07-20-2008 06:25 AM                     Hi Peter Thanks for your reply. Ours definatley dont have a pre amp card, it was the first thing I looked for. I removed all the transit screws myself and fitted the soundheads to the projectors along with the field engineer. My comments about lack of support is beacuse both the field engineer and Ernemann will not accept that there is a problem here. I find that the engineer has insulted us personally at the cinema by trying to tell us that the readings on the scope and spec. analyser are 'fine' when they clearly are not and also that microphony is acceptable as is the poor sr sound. Given that the sound heads are so sensistive as far as this microphony goes and its so clear in the cinema when we run the projector with no film in. The CP650 must be processing the microphony along with the film soundtrack so this must be the cause of the poor sound. By the way Peter, we met once at Omnex office, I was there with Steve and Alan some years ago, nice to "speak" again  |  IP: Logged Pete Naples Phenomenal Film Handler Posts: 1565 From: Dunfermline, Scotland Registered: Feb 2001 posted 07-20-2008 12:34 PM                     We did? Sorry I don't recall, mind you I can scarcely remember what I did yesterday, never mind 10 odd years ago I've been in the office 3 times in 12 years or however long it is now. Was it John Chapman who visited your cinema? You learn something every day, like I said I look after a lot of Ernemann 15, I have never seen one without a pre-amp of some sort. Still I stand corrected. I am still amazed that they can't and won't help, as that's been anything but my experience of the company.  |  IP: Logged James Whittle Film Handler Posts: 8 From: denbury, devon, uk Registered: Jul 2008 posted 07-20-2008 12:58 PM                     Hi Peter Yes it must have been 1999 ish we met. I was with Apollo then and Martin Dean was our engineer. We also had a chap from wales who worked for Omnex but he died, I feel bad that I cant remember his name. Yes it's John who has been servicing for us. I think he is a great guy but he seems to tow the Ernemann Line far too much when you have a problem, although last week he was highly embarrassed that Ernemann had sent back the soundheads misalligned and without the microphony repaired so I did feel bad for him. Just last year it took 5 months to get hold of replacement lasers (that worked and fitted our projectors) and then another 2 months to get replacement friction cards. Heres the strange thing Peter, our 2 projectors were ordered and made at the same time yet there are so many differences between the two. main drive belt spindles, acutal soundhead laser mountings, and other smaller items. I find that when we order spares, not even John or Ernemann can get the exact part the first time. Prime example - the motor drive belts slip off and hit the shutter and nor John or I could stop it. One projector has side guards on the top spindle, the other doesnt. Ernemann sent us a guide for the pulley and it dosent fit, the drawing that came does not look anything like our top shutter / belt pulley. We have cured this problem by shimming the front left hand corner of the motor mounting bracket. Anway.. keeps it all interesting I suppose.. If youre ever down in devon come and have a pint with us! Cheers  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-20-2008 12:59 PM                     If all the gain is in the preamp of the CP650 then your cable run alone would pick up all sorts of noise I have had always good luck with ernamann  |  IP: Logged James Whittle Film Handler Posts: 8 From: denbury, devon, uk Registered: Jul 2008 posted 07-20-2008 01:09 PM                     Gordon, thats a good point. I know that the noise is being picked up on the pcb card on the end of the light pipes but of course the cable is terminated at this point also. I am wondering weather to do an experiment and try adding a preamp on one of the projectors. We have some great audio guys working in the college across the road.. Ill let you know Thanks  |  IP: Logged Richard Fowler Film God Posts: 2392 From: Ft. Lauderdale, FL, USA Registered: Jun 2001 posted 07-20-2008 02:20 PM                     During the 1990's ownership changed twice at Ernemann. There are changes within the 15 series. Example the lamphouse focus mechanism was changed from metal castings to metal stamped parts; change of drive motor to Papst (similar to Kinoton) and some connectors. Forward scan "red light" set-ups will work better with a boost pre-amplifier.  |  IP: Logged Pete Naples Phenomenal Film Handler Posts: 1565 From: Dunfermline, Scotland Registered: Feb 2001 posted 07-20-2008 04:49 PM                     Sorry James, I can't place you, but it's nothing personal. I meet so many projectionists, often only once. Martin is in the US now, he married an American girl and emigrated with her. The engineer from Wales you are remembering was Paul Pool, strange I was only talking to someone up here about him on Friday. Bowel cancer took him at a far too young age. It sounds to me like you've got machines made at the crossover between designs, but I'm still gobsmacked at the troubles you're having. Perhaps you could lay your paws on a USL Jax Light pre-amp? For the purposes of experimentation if nothing else.  |  IP: Logged Ben Wales Jedi Master Film Handler Posts: 602 From: Southampton. England Registered: Jul 99 posted 07-21-2008 11:27 AM                     quote: James Whittle Im new to this forum but have been a projectionist for around 22 years Well Well, the very same Mr Whittle is back!. I wondered if he has settled all those unpaid bills from the Plaza Cinema Saga we all remember some years ago!.  |  IP: Logged

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