Film-Tech Forum ARCHIVE: Ultra Stereo sound

my profile | my password | search | faq & rules | forum home

»	Film-Tech Forum ARCHIVE » Operations » Film Handlers' Forum » Ultra Stereo sound

Author

Topic: Ultra Stereo sound

Todd Leach
Film Handler

Posts: 18
From: West Liberty, IA, USA
Registered: May 2001

posted 06-02-2001 12:05 AM

I have an Ultra Stereo processor that has recently been "upgraded" from center surround to four channel. I feel the quality of the sound has diminished since going to four channel. What I mean is when I had center surround the sound was big and full, you could feel the subwoofer in your chest all frequencies were fully represented. Now with four channel I seem to have an abundance of high frequency sound and not enough low frequency, not only from the subwoofer but also the low cabinets. In fact I don't think the subwoofer signal is right. If I just listen to the subwoofer I can hear pretty much everything that is in the center channel, it is just muffled and very quiet. The tech that set it up for me said he increased the volume output on the cards so instead of running the fader at 6 to 7, I now run at 3. Can this cause the problems above? I have tried switching the processor back to center surround and there is no change in the sound quality, and the CD player sound also has the same sound quality as film sound. The Ultra Stereo processor is a JS 200, other componets are:
Speakers:
Center EV Variplex (tri-amped)
Left & Right EV Variplex B (bi-amped)
Subwoofer EV TL3512
Surround EV TS8-2
Amplifiers:
QSC USA 900's & 1310's
Crosovers:
EV Dx34A (three way configuation)
Odyssey products Bi-amped VF Series
Any insight on other things to check would be greatly appreciated.

| IP: Logged

Adam Martin
I'm not even gonna point out the irony.

Posts: 3686
From: Dallas, TX
Registered: Nov 2000

posted 06-02-2001 01:26 AM

It would seem to me that if you're only running the fader on 3, then something is horribly wrong in the B-chain setup. I can't think of a good reason for the tech to "increase the volume output on the cards" with what I would assume is new equipment. This would only cause the signal to the amps to be overmodulated and sound like crap.

My question to the group: Why would one tri-amp the center channel and only bi-amp the L/R channels? Would this not give a really funky EQ? Never seen this done before.

| IP: Logged

John Walsh
Film God

Posts: 2490
From: Connecticut, USA, Earth, Milky Way
Registered: Oct 1999

posted 06-02-2001 01:34 AM

Dumb question; Did a person who knows what they are doing align your system? The equipment seems like decent-quality stuff.

Setting the fader to "7" is pretty much the standard.. even for non-Dolby units, but setting the fader to play back at "3" does not seem to be causing your problem.

What does your tech say? Is he acting like he is all done with the job? It sounds like (to me) it still needs work.

| IP: Logged

Paul G. Thompson
The Weenie Man

Posts: 4718
From: Mount Vernon WA USA
Registered: Nov 2000

posted 06-02-2001 01:58 AM

I agree with Adam's first sentence. I would recommend a complete alignment of the "A" and "B" chain.

Also, the later models of the Ultra-Stereo have dip switches on the mainboard. Make sure they are set to the proper positions. Some people forget about them when the unit is upgraded.

I have had some problems with the newer EQ cards, but it was only a situation where they worked, didn't work, or worked only only when they felt like it.

| IP: Logged

Brad Miller
Administrator

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

posted 06-02-2001 05:15 AM

Simple answer: You need to fire that tech who calibrated your sound system and demand a refund of whatever you paid him for that "service". Wow, that's just pathetic!

| IP: Logged

Gordon McLeod
Film God

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

posted 06-02-2001 11:50 AM

The JS200 has dip switchs on the motherboard to program its formats and it will do some very weird things if they are set incorrectly.
Since the CD sounds just as bad it is probably in the A chain the problem lies.
Out of curriosity what type of Pinknoise generator was used and did he use a multiplexed microphone set up and what analyzer was used.
THere is also a possiblity that there is a wireing error in the rack
Typically the fader will be between 5.5-6 for most films on an audience average
Also who was the engineer that set it up and did he do the whole upgrade of speakers and amps

| IP: Logged

Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 06-02-2001 01:52 PM

I'd be willing to bet it was MTS that set it up. They aren;t worth the powder to blast a bullett out. Get a new service tech that knows what he is doing and that has an R-2 and knows how to use it.
Mark @ GTS
p.s. Great picture Todd!

| IP: Logged

Todd Leach
Film Handler

Posts: 18
From: West Liberty, IA, USA
Registered: May 2001

posted 06-03-2001 12:42 AM

To answer a few of your questions, the same tech that did the center surround and made it sound so good also added the four channel so I have faith that the tech knows what he is doing. For pink noise he used something that slides right in the processor and has switches that let him switch center, left, right, surround. I don't know the model of real time analyzer he used, but it only had one mic. I checked the switches on the processor and they are all in the off position and as far as I can tell wiring looks correct.

I should add the sound is not absolutly horrible, it is lacking a bit in the low frequency area especially the subwoofer. In fact I think if the subwoofer was working properly it would probably sound fine. As things are with the other speakers on, I can have the subwoofer on or off, it dosen't matter because you can't hear it. I do have the subwoofer output on the format card all the way up and from the processor it goes to a 1310 amp mono bridged, wide open. You would think it would make some noise. You can hear it if you turn the other speakers off, but the stuff coming out of it isn't just subwoofer stuff. I can hear dialog and other things, low stuff is louder but it does not woof like it should. I have hooked up other speakers to the amp and they produce the same thing so I don't think it is a speaker problem. I have played other material through the amp and it has played fine so I don't think it is an amp problem. CD's sound the same as film so I don't think it is an alignment problem. Everything is leading me back to the processor.

I read in the manual that the subwoofer output comes from summing the center left and right channels and putting them through a band pass filter and such. Can this circut be the culprit? If so is it part of the format card or somewhere on the processor board? At any rate it sounds like I should get the tech back and go through some stuff.

| IP: Logged

Darryl Spicer
Film God

Posts: 3250
From: Lexington, KY, USA
Registered: Dec 2000

posted 06-03-2001 04:26 AM

check to make sure that the wiring to the subwoofer is correct. Posative to posative and negative to negative on the wireing. Also if you have another ultra stereo unit sitch the format cards and see if u get a subwoofer improvement and does the bad sound move with card. You could have a bad format card. Also some of these format cards have two subwoofer adjustments one is for digital and the othe analog. Make sure u are turning the right one. You will have some dialouge bleed into the sub channel this is normal on ultra stereo units. I like the dolby subchannels better. I think they sound better.

| IP: Logged

Michael Elam
Film Handler

Posts: 84
From: Clarksville, IN, USA
Registered: Mar 2001

posted 06-03-2001 02:35 PM

I have installed 100's of the JS 200, as well as upgrades from center/surround to four channel, if aligned and tuned correctly you can make them shake the walls and sound super, Your tech did a lousy job, must have been NCS!

| IP: Logged

Randy Stankey
Film God

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

posted 06-04-2001 12:04 AM

I can see how somebody would mess up a job like this and I'm not going to slam your tech for that but I would point out that ANYBODY who does ANY kind of work for hire should have some kind of final testing/approval procedure.

Usually when I make adjustments to the sound system I go down to the theatre and listen to it in person. Then, if there is time I get the manager to come down and listen too. If he/she has any suggestions or complaints I fix them right then. Before I leave I tell the manager to keep an eye on it for a while and let me know if everything's OK. 9 times out of 10 there are no problems but every so often I need to go back and make changes.

Since I work on salary payment isn't an issue for me but I would say that your tech ought to come back and tweek that system up for you at no cost. (Or at least at reduced cost.) Before he leaves you ought to have the opportunity to listen to the sound and give final approval.

This only makes sense. Even a hairdressers will tell their clients to come back the next day if they don't like their hairdo!

| IP: Logged

All times are Central (GMT -6:00)

Printer-friendly view of this topic

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.