Sound Reinforcement in a TV Studio

Hi folks, looking to tap some of the collected wisdom here.

I'm associated with a small public access TV station that occasionally does productions involving local bands (of all varieties - including rock.) The studio is about 30' x 40' with a 16' ceiling. It's a typical TV studio with concrete floor and ceiling, cinderblock walls but with a lot of drapes around. Acoustics in the studio are just okay for television, not quite dead enough but quite usable. We have a pair of Technics speakers hanging from the ceiling for general PA use now. Not sure of the model number but they are three-way and have a 15 inch woofer. They have been adequate for general playback but we dont attempt to use them with the bands.

We'd like to upgrade the system so we can have better playback and provide decent sound when we have a band in. I have the opportunity to buy a pair of JBL Sound Factor SF25s for $450. These appear to be identical to the new JBL JRX125.

So I have some questions:

1. The Sound Factor and JRX lines are apparently an attempt to provide more coste effective speakers to the sound reinforcement market - anyone know much about them? Are they up to usual JBL standards and a good choice compared to similarly priced units from other manufacturers?

2. Would a pair of this particular unit (2-M115-8A 15" drivers and 1-2412H-1 driver per cabinet) be appropriate to my task?

3. How much power will I need to drive them? They are rated at 500W and 2000W peak. We currently have an amp rated at 75W per channel I'm assuming I'll need more than that but can I get away with 150W? Do I need to go as high as 500?

Any advice would be appreciated.

Dave

Hi droh

I need to ask a few questions of you so that I understand the application of your intended system.

You said that the boxs will be used for playback.Is the playback for a live studio audience to hear?

Is your intent to mix the bands through this system for the studio audience or for the broadcast out to the airwaves?

If you are doing this for the broadcast,what method are you using to get that ambient sound from the intended speakers to the broadcast console?

I have a fair amount of experience with mixing bands in studios that go live to the broadcast mix. Its always chaotic!!!!!!!!!!

Lemmie know and I will try to help.

Best regards,

Oldmics

'Not about speakers, but with both a concrete floor and ceiling you'll get a huge sonic improvement putting carpet on the floor. If you're on a budget you can often get large pieces of used carpeting that have been taken out of homes/offices from carpet dealers - they're usually glad to have it hauled away instead of paying to have it disposed of. And if you can also figure out something to deaden the ceiling a little, all the better...

John

Thanks Oldmics, let me try and answer your questions:

Quote:

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Originally Posted by Oldmics

Hi droh


I need to ask a few questions of you so that I understand the application of your intended system.

You said that the boxs will be used for playback.Is the playback for a live studio audience to hear?

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The studio isn't quite that large, no real studio audience, maybe a few people standing around.

Quote:

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Originally Posted by Oldmics

Is your intent to mix the bands through this system for the studio audience or for the broadcast out to the airwaves?

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The intent is to take the mix off the board (or perhaps a subset of it) and feed that to these monitors for the band to hear themselves. The monitors will of course also be used for other purposes. In order of most frequent use that would be:

1. Hearing the opening and closing music for a show or a tape roll in during a show, the Technics speakers have been adequate for this task.

2. Hearing pre-recorded music when a singer doesn't have a live band to accompany them. The Technics have been disappointing for this.

3. The scenario described in this post - feeding the mixed audio to a band performing. We never use the Technics for this and instead use whatever capability the band has of their own.

Quote:

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Originally Posted by Oldmics

If you are doing this for the broadcast,what method are you using to get that ambient sound from the intended speakers to the broadcast console?

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The audio for broadcast would come off the mixing board, these speakers are for the band to hear what that sounds like.

Quote:

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Originally Posted by Oldmics

I have a fair amount of experience with mixing bands in studios that go live to the broadcast mix. Its always chaotic!!!!!!!!!!

Lemmie know and I will try to help.

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Any help you can provide would be very much appreciated. I think we will probably go ahead and buy these unless anyone warns me that the SF line is not good. My major concern is how much amplifier I need to drive them.

Quote:

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Originally Posted by johnaec

'Not about speakers, but with both a concrete floor and ceiling you'll get a huge sonic improvement putting carpet on the floor. If you're on a budget you can often get large pieces of used carpeting that have been taken out of homes/offices from carpet dealers - they're usually glad to have it hauled away instead of paying to have it disposed of. And if you can also figure out something to deaden the ceiling a little, all the better...

John

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Yeah but in a TV studio you need a nice smooth floor for moving the cameras. So we are kind of going the opposite route, we are adding sound abatement to the ceiling and the top of the walls. It's a mixture of acoustic tile and some fabric covered panels. We already have some sound deadening foam on some other walls and there are curtains running around the majority of the studio space.

Buy Em.


You need about 600 watts to get loud preformance out of them with some headroom.

500 watts will be just fine if you are doing the same chores as the Technics are providing now.The 150 watt amp that you have will not do the job in a safe manner.I would budget for a 500 watt or greater amp.

I would keep a close eye on them when using D.I.s (direct injectors) as used on acoustic insturments,bass guitars,keyboards,etc.
Musicians have a habit of unplugging there cable causing a momentary short which is hard on the tweeters.Always ask the preformers to wait until the system is turned down before unplugging.

The tweeters are the weak link in those cabinets-but still MUCH more stouter than the currently used Technics system.

It should work well for your application.

Good luck.

Hey, droh...

Sorry to be late to this - although there is little to add to anything Oldmics posted. One thought, but it comes at a cost...

My band did one of these a few months back, and we brought our wedges for band monitors. The flying mains were poorly located and impossible to bring to the needed gain for the band, without being too loud for the studio. The wedges were placed right at the feet of the artists and directed right at them, outside the cardiod pickup pattern of the vocal mics. So, you might consider adding some wedges to the 2005 Budget, and use your 75w amp for these (that is too small, but should do for a while). Likely your console has some Aux you aren't fully using that could be applied to foldback.

As well, with the wedges firing off (away from) the floor, being on finished concrete did not pose oversized feedback issues for our show. We got it done, fine.

Post some pics of the studio, and conole, if you get a chance. We love that stuff... :yes:

Quote:

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Originally Posted by Oldmics

Buy Em.


You need about 600 watts to get loud preformance out of them with some headroom.

500 watts will be just fine if you are doing the same chores as the Technics are providing now.The 150 watt amp that you have will not do the job in a safe manner.I would budget for a 500 watt or greater amp.

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Thanks for all the valuable info Oldmics. One question, is that 600 wattas per channel or for the two channels?

Hey Bo....

Thanks for your input too.

Actually we will not be flying these beasts, they'll be down on the studio floor and moved into an appropriate position for band gigs.

Pics might not be so fascinating, after we fix up the studio a bit more I'll take some shots though. The current board is just a 12 input Mackie, but we are hoping to upgarde that to a bigger Mackie next year. When we do bands they often bring their own board.

Quote:

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Originally Posted by droh

When we do bands they often bring their own board.

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I think I love you guys...

And, I'm betting Oldmics is suggesting 600w, per - not that you'd ever get there, but he's thinking headroom...

You will need an amp that can do 600 per side @ 4 ohm.

Run 1 cabinet on each side of that amplifier.

Plenty of them out there.

Oldmics