8mm Forum: Vibrations on Beaulieu 708 EL stereo

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Posted by Maurizio Di Cintio (Member # 144) on August 19, 2016, 07:25 AM:

Hi, all.

I have just received this projector: I inspected it thouroughly, cleaned it where necessary while lamp warm up; and when I was finally confident, I screened a couple of shorts.

Great performances indeed, very silent machine, but with the variable shutter set to 2-blades the projector suffers from a slight but noticeable vibration at 24 fps (only) which seems to riverberate on the test film resolution (SMPTE test film).

Everything is perfect when the shutter is set to 3 blades.

Has anyone ever experienced this? Is it normal? I might guess it is due to the fact that in 2-blade mode, one of the blades is hidden behind one of the remaining two, and the overall mass of the shutter is much less balanced in my opinion...

Any hints? Thank you

Posted by Andrew Woodcock (Member # 3260) on August 19, 2016, 07:32 AM:

Check it is wide open Maurizio.

I was warned of excessive vibration in two bladed shutter mode on these myself before finally owning one.

To be honest, i have never found this to be the case.
I watch all 24fps films on two bladed shutter mode and both the noise levels and vibration levels are completely unaffected to my ears whether two or three mode is utilized.

Mine is always placed on a standard projector table and that stands on a carpeted floor.

Maybe if it was on a solid floor it may become more noticeable, i do not know. But even to the touch of a finger on the main chassis, the machine isn't noticeably more affected which ever mode and certainly isn't like an washing machine on fast spin with a pair of trainers in! [Big Grin]

I will place a glass with water in it next to the machine running on the projector table.
I will video it and post a link here to see whether or not yours is similar in its behaviour.

https://vimeo.com/179453269

Posted by Maurizio Di Cintio (Member # 144) on August 19, 2016, 07:37 AM:

Thanks, Andrew. I'll do the check you suggested. Cheers!

Posted by Andrew Woodcock (Member # 3260) on August 19, 2016, 07:51 AM:

Nothing too drastic observed Maurizio.

This was on 2 blade 24fps mode btw. [Smile]

Posted by Paul Browning (Member # 2715) on August 19, 2016, 08:04 AM:

I have this model too Maurizio, it does have a more vibration than say a fumeo or the gs, it maybe because the third blade disappears behind one of the two remaining shutter blades, this must in some way unbalance the shaft it rotates on because you shifting the weight to one side of the fixing, similar to balance weights on a car wheel. Just a thought.

Posted by Terry Sills (Member # 3309) on August 19, 2016, 08:15 AM:

Andrew
I find that my projectors always work better with a glass of wine next to them. Especially when it's empty [Big Grin]

Posted by Andrew Woodcock (Member # 3260) on August 19, 2016, 08:17 AM:

yes it's true as Paul says, that by having the design it has, on two bladed shutter mode, one side of the shutter has two blade thicknesses while the other opposite side is only singular.

However, as said and as can be seen here now, it certainly isn't anything too drastic and it never causes me any level of concern both from a noise or vibration standpoint, or even a mechanical one.

The blades are after all, very lightweight in their construction, so we are not talking huge amounts of imbalance here. [Wink]

To be honest, having watched it back again just now, it appears the water is almost still when no sound is being replayed, so it certainly isn't much at all when the shutter is wide open.

[ August 20, 2016, 03:35 AM: Message edited by: Andrew Woodcock ]

Posted by Alan Gouger (Member # 31) on August 19, 2016, 08:17 AM:

Wow Andrew please provide a video of the film that is projecting I love RR and had no idea it was avail on S8. You are the man:)

Posted by Andrew Woodcock (Member # 3260) on August 19, 2016, 08:18 AM:

[Big Grin]

Soon Alan soon ha ha.

Elsewhere though Buddy! [Wink]

It certainly makes the films look good even when they perhaps aren't Terry! [Big Grin]

Posted by James Wilson (Member # 4620) on August 19, 2016, 11:27 AM:

I think with two blades running at 24fps it`s probably
trying to take of!

Posted by Andrew Woodcock (Member # 3260) on August 19, 2016, 02:53 PM:

Bloody Nora, I thought Pat was back for a mo there! [Big Grin]

Posted by Maurizio Di Cintio (Member # 144) on August 20, 2016, 07:59 AM:

Thanks for the posts, guys. I think, now, it's nothing to worry about.

But I have another question: my machine, during recording, seems to only allow sound check from the monitor sound head (the extra one), which plays back the sound just recorded a split second before by the regular head. Is there a way to listen to the sound being put in the machine (source monitoring rather than recorded monitoring) as it is possible on all other machines I own???

BTW has anyone got a scan of the manual?
BTW2: great sound, really impressive and with no particular difference between main and balance track!!!
Thanks again.

Posted by Andrew Woodcock (Member # 3260) on August 20, 2016, 08:41 AM:

Try switching the public address switch to on Maurizio.

I don't ever use my Beaulieu for any of my recording tasks, but when I very first got it, I remember having to do this to hear an input when trying the recording modes out.

I might have even had to do this for track to track transfer, I can't quite remember now, it was many moons ago.
[Smile]

As for a manual, I purchased mine from Beaulieu.de

They do English, French and German versions for your model.

I don't have a scanner unfortunately, but I could photograph every page of my English manual if this helps?

Posted by Paul Browning (Member # 2715) on August 20, 2016, 08:56 AM:

Hi MAURIZIO, you could put a small mixer between the source and projector, this will allow you monitor input before recording and adjust the output recording on your projector vu's. With a better quality mixer you can adjust bass and treble too, which I find helps.

Posted by Maurizio Di Cintio (Member # 144) on August 20, 2016, 12:32 PM:

Thank you, Andrew and Paul.
The PA suggestion works indeed. It doesn't make much sense to me but it works.

Putting a mixer between audio source and prj is a good idea especially to balance the two tracks when recording in stereo; it has alvways buffled me why was it both Bauer and Beaulieu didn't consider individual rec level controls for each track on both their top of the range machines!!! Fortunately the Vu-meters on the 708 also work during playback which - I found - is quite uncommon according to "Europe-school".

So thanks everybody for the feedback. Now the only issue left is a problem with the balance slider: it works very erratically ie when it it pulled all the way to R channel only it will occasionally also play both channels and vice versa. Perhaos some contact cleaner might help. Have a nice week end.

Posted by Paul Browning (Member # 2715) on August 20, 2016, 01:38 PM:

Hi Maurizio, not sure if these can be obtained now, probably an odd value and size. I have though recovered these to use again in other machines, not projectors, with a simple pencil lead ?. These are just carbon tracks and they either wear out or go high resistance and have flat spots in them where they do not work at all. If you can gain access to the slider from the from, they have just a dust cover over them, remove the slider knob, and sharpen a pencil maybe with a pen knife, then reach in with the pencil and use the lead to replace any carbon along the track, sounds mad or crazy but, it was a tip I got from a very good sound engineer who worked for sony, he was no fool, it definitely worked, and will save you dismantling the whole machine to get to this to desolder. The switch cleaner may work too, but it can have the opposite effect on some switches and can attack the old style plastic and make them fall apart !!!!. Good luck, let us know how you get on.

Posted by Andrew Woodcock (Member # 3260) on August 20, 2016, 02:19 PM:

Great tips from Paul there.

Also there are some linear pots you can angle the moving slider tip to use a slightly different section of the carbon track. This then similarly can give some sliders a new lease of life.

Great care though has to be taken, of course, if attempting to dismantle these things though.

I've never had to look into any of mine so far touch wood, so at this stage I have no idea of the type used on these though.

Posted by Maurizio Di Cintio (Member # 144) on August 21, 2016, 12:59 PM:

Thank you guys, incredible suggestions!!! Perhaps I'll give them a try although indeed I have noticed the "angle thingy" metioned by Andrew. As a matter of fact, I am being a bit picky on this balance slider when in fact it's not a real issue. Should I ever need to use this machine for screenings with my regular audience, I'll certainly hook up it to an external amplifier and control balance etc from latter. Plus the machine came with a 2-year warranty: I hope I'll never need it and the balance is not so serious as to justify sending it back. So I am 98% satisfied. Thanx again for dissolving a few perplexities.

P.S.: Andrew I'd never ask you to take shots of your user's manual pages, that would be a painstaking process. I'll probably by one from Wittner or look for an Italian one on my local S/8 forum.

Cheers everybody.

Posted by Andrew Woodcock (Member # 3260) on August 21, 2016, 02:08 PM:

I will check through my digital downloads Maurizio to see what
I have in the way of manuals on these.

I certainly don't mind taking a photo of each page and mailing it to you Maurizio if I don't find a digital version.

I'm almost certain I won't have an Italian version, but given your excellent English Maurizio, I don't believe you'd go far wrong if I can find you an English version.

Posted by Maurizio Di Cintio (Member # 144) on August 21, 2016, 04:02 PM:

Thanks, Andrew, I'm flattered [Roll Eyes]

Posted by Andrew Woodcock (Member # 3260) on August 21, 2016, 04:34 PM:

Send me your e mail address Maurizio,by PM.
I will get you something over to you in pdf format or jpg format tomorrow even if in future, you decide to get yourself an official paper copy. [Wink]

Posted by Maurizio Di Cintio (Member # 144) on August 21, 2016, 05:00 PM:

PM sent.

Posted by Andrew Woodcock (Member # 3260) on August 21, 2016, 05:21 PM:

I have now sent you the only two I have in pdf format Maurizio.
I hope these are of some use to you in the meantime. [Smile]

[ August 21, 2016, 07:10 PM: Message edited by: Andrew Woodcock ]

Posted by Maurizio Di Cintio (Member # 144) on August 22, 2016, 04:12 AM:

Great stuff, Andrew! Thank you so much!!!!

Posted by Andrew Woodcock (Member # 3260) on August 22, 2016, 04:14 AM:

No worries my friend. [Smile]

Sent you another mail Maurizio regarding the service manual for these.A very useful addition in ownership of one of these. [Smile]

Posted by Maurizio Di Cintio (Member # 144) on August 22, 2016, 08:18 AM:

Indeed. I hope i can return the favour one day.

Cheers.
M.

Posted by Andrew Woodcock (Member # 3260) on August 22, 2016, 08:30 AM:

Everyone helping each other out in their hour of need is what forums are all about and built for imo Maurizio.

Well that and sharing the delights of this hobby for the most part! [Wink]

I know all too well Maurizio, you'd always help others out whenever you can, so all is good my friend. [Smile]

Posted by Phil Murat (Member # 5148) on August 22, 2016, 02:22 PM:

Hi Maurizio,

I have experienced " Low frequency" Vibrations on my Beaulieus 708 too......

I observed the Tubine Wheel is secured with a Diam 4mm screw with a big head. This is a big mistake from Beaulieu !!!!

No more vibrations when replacing for a headless short screw.
The best is to install an other screw (same size) in oposite position.

To be note vibrations has bad effect on motor peformances, and premature front bearing wear.

Let me know

Phil

Posted by Andrew Woodcock (Member # 3260) on August 22, 2016, 02:32 PM:

Yes, the fan should be fitted with an M4 unbrako grub screw of exact dead length preferably, as I stated in the past here.
This will of course assist with any imbalance issues surrounding the main motor shaft, but of course, has no association with any vibration witnessed from the Shutter Shaft assembly itself.

The fan on mine was particularly difficult to remove as the cheese head screw had been over tightened originally causing a large burr between shaft and hub.

Unbrako screws are very hard high tensile steel. They do not round easily but can and will cause similar burrs if over tightened.
The fan really doesn't need much securing. The hub is made of aluminium and is therefore very lightweight.

Just enough torque on the Allen key, is good enough here!

The motor shaft is only made from mild steel so it can and will easily become damaged by any over tightening of the screw.

[ August 22, 2016, 04:45 PM: Message edited by: Andrew Woodcock ]

Posted by Andrew Woodcock (Member # 3260) on August 23, 2016, 03:05 AM:

In answer to some of your earlier queries Maurizio, I have read that the reason you ordinarily cannot monitor input sound through the internal or external speakers without switching to PA was due to expectation by design of high levels of feedback in certain instances due to the power of the amplifier.

This was a design characteristic in order to protect itself when inputting to the PJ by either microphone or external source.

Ordinarily, the suggested method of monitoring during recording passages is via the two speaker output 2 pin Din sockets with a pair of headphones.

I also believe it is by design that Eumig and Bauer chose to leave the VU meters inoperative during playback just so as to not excessively run the meters in non critical applications.
Beaulieu and Elmo have their meters illuminated and operational at all times but to some, it is arguably unnecessary and just places added use to the lamps and meters themselves.

Posted by Maurizio Di Cintio (Member # 144) on August 23, 2016, 06:50 AM:

Thank you again, Phil and Andrew, for your precious inputs. I also feared the vibe could put unnecessary strain on the shaft bearings.

Fact is my unit came with a 2-year warranty, one of the screws of the back cover is covered by a sticker which, if broken, will make such warranty void.

So there's no way for me to have a direct look at the innards of the beast, for the time being; so I'll leave it in 3-blade mode and I should have no problems.

I also see your point, Andrew, regarding acoustic feedback etc. In this respect a socket for headphones would have come in handy; I do not know if it's possible to link a headphone to the DIN socket; it's certainly possible to put a mixer in between with a headphone jack and use it for monitoring. A breeze today, maybe not so pleasant at the time this projector was introduced, especially due to the cost: after all higher-end Bauer's and Eumig's have headphone jacks... Just my opinion, though and certainly a minor design flaw which does not lessen the unique features of this machine.

Posted by Andrew Woodcock (Member # 3260) on August 23, 2016, 10:52 AM:

I too would have prefered a separate 6.3mm stereo headphone jack, but on European models of the time, it was non standard practice to mix both European and Japanese standards of socketry.

The Bauer models come with a dedicated headphone monitoring socket in the shape of a 5 pin Din socket.
The Beaulieu manual just advised us all to connect our headphones via the 2 pin Din stereo speaker sockets.
Ironically though, it does not provide us with an adaptor lead in the original accessories though to facilitate this.

Another fairly large oversight on their behalf given the price of these things and the overall standard of the machine.

[ August 26, 2016, 06:19 AM: Message edited by: Andrew Woodcock ]

Posted by Maurizio Di Cintio (Member # 144) on August 23, 2016, 11:56 AM:

I agree.
Update: after cleaning the balance slider the problem seemed to persist; but I accidentally tinkered with the stereo/mono/duoplay selector nearby and realised that was the actual culprit! I "poured" as much contact cleaner fluid as I could, switched it back and forth and there it was: perfect! Now the balance slider really works sort of like a "mixing device" between the two tracks when playing back in mono.
Also the awareness of a whole sound head not really used circa 70% of the time but still subject to wear (I am referring to the monitor head) made me shiver, so I found a way to keep the presseres defeated whenever such head is not needed. Same for the balance track of the regular head. Applying such contraptions on this machine is even easier than on the Eumig: no need to switch between two different sound pressers cartridges here: just open up the sound assembly (cleaning mode) gently push the pressers up with a finger and while the pressers terminal are protruding, one simply inserts a piece of plastic circa 1 mm thick cut and shaped to fit, which will keep the presser(s) away from the tracks.

Posted by Andrew Woodcock (Member # 3260) on August 23, 2016, 11:29 PM:

Great news there regarding the slider / switch initial fault Maurizio. I am pleased all now is fully working for yourself and in time, when you're warranty has perhaps elapsed, I'm sure you'll want to balance the motor shaft to the best you can by adding a headless fastener.

One of the main attractions of the outstanding image qualities obtainable from these, is the additional brightness obtained without detriment, from using the two bladed shutter facility whenever possible (24fps).

Posted by Andrew Woodcock (Member # 3260) on February 04, 2017, 06:17 PM:

Do I love You?

3 very happy and satisfied years into ownership...

Indeed I Do! [Smile]

https://www.bing.com/videos/search?q=do+i+lo ve+you+frank+wilson&view=detail&mid=78B17E1B9CF0AB8BC16178B17E1B9CF0AB8BC161&FORM=VIRE

Not one quibble nor squabble since bedding this one in.
Perfection personified!

Gillette, the best a man can get. [Wink]

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