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Topic: 16mm Sound problem

Ed Johnson
Film Handler

Posts: 24
From: Lancaster, MA/Appleton, WI
Registered: Jul 99

posted 10-13-1999 04:58 PM

Hi-

I recently became involved with a film organization at the college I'm currently attending. Although I've had a good deal of experience working projection at a 15-plex, I've never had the pleasure of working with 16mm prints before.

The problem I'm having is that the sound quality is horrible. We're using a relatively old Eiki Xenon projector. The only sound out put is a 1/4" plug labled 8ohms. This plug was originally designed to power a speaker, not to be used as a line output. I'm trying to connect this to a RCA type input on the PA for the audtiorium. Do I need to run the signal through anything between these to ports? I don't know what the impedance of a line input is.

Currently the sound is slightly distorted and lacks definition making it hard to hear dialogue over background music.

Any advice would be greatly appreciated!

BTW, the image is great. Strangely enough this little Eiki projector projects a rock steady picture...

------------------
Ed Johnson
Lawrence University
Appleton, WI

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Randy Stankey
Film God

Posts: 6539
From: Erie, Pennsylvania
Registered: Jun 99

posted 10-13-1999 05:16 PM

Once in a great while we have to run 16mm here at the college. We run the sound output right into the mixing board for the auditoriums 'regular' sound system. (As oppoesd to the 'movie' sound system.)

We have to start by adjusting the volume and tone controls on the projector itself then adjusting the EQ on the sound board and setting the trim and gain.

Set the "tone" controls on the projector to the mid-position and the volume in the lower 1/3 of its range. Then 'trim' and EQ from the board. If it isn't good, adjust the tone and volume on the projector then re-EQ the board. It usually takes us 2 or 3 tries but we can get 'decent' sound eventually.

I can't imagine the sound from these little projectors would be really good but they are acceptable for small audiences. It takes a little tinkering to get them to sound good for an auditorium-sized audience.

I'm no sound engineer but if I work at it, I can get passable sound this way.

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Scott Norwood
Film God

Posts: 8146
From: Boston, MA. USA (1774.21 miles northeast of Dallas)
Registered: Jun 99

posted 10-13-1999 06:49 PM

I'm not sure what model Eiki you have (we had EX-6100s at my college...nice picture and sound quality, only fair quality of construction), but most of the xenon projectors do have a line output.

The portable Eikis that don't have a socket labelled "line out" do have a "hidden" line output: use a stereo 1/4" phone plug and take the output from the center ring and the tip; this should give you line-level output that can be connected to a line-level input on a mixing board or whatnot.

You could also rig something up to take the output directly from the solar cell and run it through a solar cell preamp or mike preamp on the mixing board, thus bypassing all of the (usually not-so-great) sound electronics in the projector itself.

Also make sure that your solar cells and slit optics are aligned properly. I have a 16mm "Jiffy Test" film that I'll loan you if you want to check this out.

At my college, we had the EX-6100s' line outputs feeding directly into a mixing board. We set up the levels to be more-or-less equal (by ear) and set the EQ to be pretty much flat. Sound changeover was controlled within the projectors themselves. It sounded pretty good, since we were using decent (not great) JBL speakers and decent Crown amps. The EX-6100 is one of the nicest-sounding 16mm projectors that I've ever used...not that this is saying much, but 16mm optical tracks really don't sound all that bad when they're well-recorded and played back on good equipment.

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Rick Long
Jedi Master Film Handler

Posts: 759
From: Toronto, Ontario, Canada
Registered: Nov 1999

posted 10-13-1999 07:42 PM

Never knew about that hidden line output on the Eikis. Neat tip (pardon the pun), Scott. Thanks.

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99

posted 10-13-1999 08:07 PM

Yes, why wasn't that bit of information in the manual when I needed it back in college???

Anyway, we always just used the technique Randy mentioned above and got quite good results from it. I'd start with your input setting on the mixer at a standard level (typically 7-8) and adjust the volume on the projector so the loudest parts of the film just hit into the red on your meters. From there, use your master gain outputs on the mixer for a volume control.

If the sound is still bad, you need to adjust those optics. 16mm is fairly easy to do, especially since it's mono. I've done it by ear before and gotten pretty darned close.

By the way, I think the Eiki line is the best in 16mm. Those things just keep running and running. My only complaint is the lens barrel/focusing assembly. It leaves a bit to be desired. Other than that...ROCK STEADY PICTURES and an automatic loop restorer (for those masking tape splices) to boot! Forget film inspections, those machines would run anything.

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Ken Layton
Phenomenal Film Handler

Posts: 1452
From: Olympia, Wash. USA
Registered: Sep 1999

posted 10-13-1999 08:33 PM

All Eiki's have the output of the solar cell going to a 1/8" miniature plug to the amplifier. I've seen alot of other people simply get a patch cord and plug the output of the solar cell into an "aux" or "mic" input on mixer or external public adrress amplifier with good results. But just don't yard out the Eiki's amplifier altogether as it also contains the exciter lamp power supply circuitry.

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Ed Johnson
Film Handler

Posts: 24
From: Lancaster, MA/Appleton, WI
Registered: Jul 99

posted 10-13-1999 09:47 PM

Thanks for all your advice- I'm going to go fiddle with the projector for a couple hours tommorow.

One other question- The splicer that they have here is a really cheap looking Kodak deal (I don't remember the model name) that does both 16mm and super 8. What I thought was strange was that the the cutting blade is not straight. Instead its cuts on part of the film with an indent and the other with a protrusion so that they fit together. This causes you to lose a frame from both and looks crappy. Why would you want to do this instead of a normal cut on the frameline?

Thanks again for all your help... This is a far cry from the Ernemann 15's I'm used to!

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Scott Norwood
Film God

Posts: 8146
From: Boston, MA. USA (1774.21 miles northeast of Dallas)
Registered: Jun 99

posted 10-13-1999 11:08 PM

That splicer would be a Kodak "presstape" model. They're pretty cheesy and require special (and expensive) tape. The only good thing about them is that they don't cost much. The curved cut is supposed to run more smoothly through some projectors.

You need to get a "guillotine" splicer. The 16mm splicer is just like the 35mm model. They show up occasionally for under $100 used. I got one in top condition for $50 a couple of years ago, with both straight and diagonal cut blades. You only need the straight-cut model for repairs to release prints.

I think that Neumade makes a 16mm splicer that's like their 35mm splicers (which are great), but I've never seen one.

If you're running acetate-base prints (unlikely if you're getting relatively recent prints from the rental companies), then you can use a cement splicer. I like the Bolex cement splicer, but the Maier-Hancock hot splicer is the top of the line cement splicer...get the 16/35 version and not the 8/16 version, if possible.

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99

posted 10-13-1999 11:52 PM

The Neumade 16mm splicer is a "wrap-around" where you only need to pull the tape across and "punch" it once. It leaves a stretch of pre-punched tape that you simply wrap around to the other side. They made excellent splices!

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Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12814
From: Annapolis, MD
Registered: Dec 1999

posted 10-16-1999 05:24 PM

Wow Scott...I never knew about the "hidden" line-out on an Eiki.

For those that don't however, Pro-Co has what they call the AV-1. It takes "speaker out" from a 1/4" input and drops it to either "line-out" or "mic-out". One nice thing it does is put a low impedance load on the projector's amplifier. Most 16mm amps do NOT like feeding high-impedance inputs. Its always a good idea to put at least 8 or 16-Ohm resistors across the ouput when padding them down.

One of the reasons for the steady pictures on many 16mm projectors is that they use "claw" type pull downs. If they are two-tooth claws like Elmo's then they run shrunken film better too.

Steve

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System Notices
Forum Watchdog / Soup Nazi

Posts: 215

Registered: Apr 2004

posted 09-09-2009 06:03 PM

It has been 3616 days since the last post.

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Laura Jean Kahl
Film Handler

Posts: 8
From: Pittsburgh, Pa USA
Registered: Apr 2009

posted 09-09-2009 06:03 PM

ok, even though this thread is pretty old, i've got an eiki 6100 sound problem.

intermittently the sound spikes and then drops out. when this problems happens it won't stop until you stop the show. sound builds louder and louder (becoming unbearably loud) then cuts down to nothing. then it starts all over again.

it's difficult to troubleshoot because the problem seems to happen randomly. of course every time i run tests nothing happens, but as soon as we bring in a visiting filmmaker with his films i'm embarrassed as all get out because the sound in freaking out in the theater.

the sound runs from 1/4" line out into a mackie mixer then into the rack through xlr.

my guess is a problem with a pre-amp in the pedestal. but again it's hard to diagnose because the problem seems so random. has anyone heard of this before? anyone have any feedback for me? i feel pretty up the creek right now.

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 09-09-2009 06:08 PM

my suspicion is it is the eiki rpeamp
try connecting the cell directly to a LoZ mike input of the mackie mixer (make sure you disconnect the existing eiki preamp first

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Laura Jean Kahl
Film Handler

Posts: 8
From: Pittsburgh, Pa USA
Registered: Apr 2009

posted 09-09-2009 07:11 PM

thanks gordon.
we have a visiting filmmaker coming in on the 20th with 4 16mm films to screen, so i'm scrambling for a solution. i've got a pgh friend who specializes in home built electronics coming in to help me troubleshoot friday. we will try this.

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Tom Sauter
Expert Film Handler

Posts: 163
From: Buffalo, NY, USA
Registered: Sep 2000

posted 09-10-2009 06:31 AM

The audio board was never this projector's strong suit (neither was anything else). Its a pretty simple operation, you can follow the wire right out of the soundhead behind the slit lens and cut it off. If you open the non-operating side cover of the projector the wires are all very accessible. All of the audio circuitry is contained in the pedestal, so nipping it anywhere before there will work.

Use caution when working on this projector, there are EXPOSED HIGH CURRENT DC LINES entering the lamphouse.

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