Film-Tech Forum ARCHIVE: Small cinema audio advice

This is topic Small cinema audio advice in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Aleksandar Obradovic (Member # 7266) on 01-08-2015, 11:50 AM:

Hi all,

Let me hear your opinions for audio speakers for small auditoriums (30-40 seats, under 100 sq meters).

1. L/R Speaker Make/Model/price
2. SW make/model/price
3. Surround speakers make/model/price

Tnx to you all.

BR Alex

Posted by Steve Guttag (Member # 268) on 01-08-2015, 12:32 PM:

Prices will vary based on where purchased and possibly special deals.

The problem with speaker recommendations is that they are WAY too subjective. People have their preferences for whatever reason.

Suffice to say, I can normally source all of my "typical" cinema speaker needs from QSC and JBL. QSC has some new speakers specifically tailored to small screens/screening rooms though one has to use a Q-SYS system with them.

In both brands...I tend to avoid the lower-end versions...which are generally the same as the upper end but with inferior drivers that "work" with the cabinets/horns of the better drivers. So for QSC, I'm normally in the SC-4xx range and for JBL in the 4000 or 5000 series.

Don't cheap out on the speakers in your sound system...no amount of EQing will overcome bad speakers (and bad acoustics).

Posted by Mark Gulbrandsen (Member # 72) on 01-08-2015, 01:00 PM:

You have to first look at your budget and decide to go passive or biamp (or triamp). Then decide what you can afford.

I just installed a set of SC-1150's in a room 38 feet long and 50 seats. The results were very impressive.

I have also installed a few dozen pair of the SC2150's in rooms that are appropriate in size for this system. This is an excellent 3-way passive speaker!

Both these speakers are shallow so you don't need a lot of space behind the screen.

I don't even bother with any JBL any longer. Harmon simply has let the JBL Cinema Division to to shit since Lynn Dean left there. I have been waiting almost two months for six 15" JBL woofers! Thats ridiculous... While they offer a few decent products the Screen Array series is junk compared to the QSC equivalents. The old 4670D and 4675 are still made however the construction quality of the bass bins is really crappy. Ever since I had some fall apart in shipping I quit using their products.

Mark

Posted by Aleksandar Obradovic (Member # 7266) on 01-08-2015, 01:39 PM:

Steve/Mark tnx for your replays. I am now browsing QSC website and there is a lot of interesting stuff. Can you tell me what are your opinions about their amps? I had several ISA series amps by QSC which were good and some QSC 10D and that's all.

What about prices? This installation will take place in SE Europe.

Posted by Steven Smith (Member # 8350) on 01-08-2015, 01:58 PM:

Mark, I'm glad you posted that about the 2150. I have 3 of them going in my screening room and haven't seen much feedback as they're a newer speaker compared to the JBL 3677 and 4722 which have been used and well received in more than a few home theaters. It'll be spring/summer before the house is built and I'm hoping they're really smooth. They'll be in a baffle wall fed off of the DCA 1644, treated room etc.

Do they hold their own well against the 4722n (passive), better? about the same?

Posted by Marco Giustini (Member # 4544) on 01-08-2015, 03:20 PM:

Alex,

QSC amps are the most reliable available - and probably the best as well.

Steve,
Why you have to use Q-Sys for those speakers? Which speakers are you referring to?

Posted by Terry Monohan (Member # 8285) on 01-08-2015, 04:56 PM:

I visit many small theatres around the USA each year. The biggest complaint I have on most of them, they place the L C R speakers in the middle of the screen so you have no separation of screen sound. I have even been as bold as to have gone backstage with the managers/owners permission and moved the right and left speakers over as far as I could to give the sound a better image. Many theatres I have even helped place the right and left speakers off the screen and put on the far right and left of the outside wall of the theatre and hid them. Some very small cinemas I have seen have the few surround speakers on the back wall and not sides. This gives a nice surround sound effect without all the speakers down the side. One old lady owner I know hooked up some Cerwin Vega Earthquake speakers to the under stage screen area and It sounded good for the small place she runs. There are some very nice crisp and bass speakers out now that sound great in a small viewing area.

Posted by Mike Blakesley (Member # 26) on 01-08-2015, 05:49 PM:

All our speakers and amps are QSC. We replaced older Peavey stage speakers and E-V surrounds with the QSCs and the system never sounded better.

Posted by Marcel Birgelen (Member # 6801) on 01-08-2015, 06:47 PM:

Regarding QSC amps, if you can afford it, they are certainly a good choice. For normal cinema applications probably the best choice you could make. While an amplifier is nothing really special and most professional amplifiers do exactly what they are supposed to do: amplify the signal without messing with it too much, reliability is also an important factor and QSC, in general, scores well on that part.

quote: Aleksandar Obradovic
What about prices? This installation will take place in SE Europe.

Are you going to do the installation yourself or are you looking for and integrator who will implement the whole system?

According to the QSC site, the only official dealer for Serbia is PAXT (operating from the UK). Maybe you should drop them a line for pricing and availability:

PAXT LTD

15 South Cambridgeshire Business Park
Babraham Road
Sawston
Cambridgeshire
CB22 3JH
United Kingdom

Phone: +44 7507 793 562
Fax: +44 1223 839 988
Email: info [at] paxt.com
Website: www.paxt.com

Posted by Steve Guttag (Member # 268) on 01-08-2015, 09:18 PM:

It is the QSC reference series that "needs" the Q-SYS dsp to operate properly.

http://qsccinema.com/products?family=Loudspeakers&series=Reference%20Monitor%20System

Talk to QSC about that. Note, in the "pro" audio world, many speakers are designed around having a known DSP crossover/tuning. That isn't too uncommon.

As for JBL...I'm not nearly as down on them as Mark. I have the ones I like and the ones I don't. Note, the 4675 is definitely history...it isn't on the price sheets anymore...the 2360 horn was being kept alive just for Cinema and most cinemas don't want to have 4-feet behind the screen to have a horn like that anymore.

As for the 4722. For the money, it is an awesome speaker. It sounds really good and works well either bi-amped or passive crossover...despite having a cheeseball crossover. It is A LOT better than the 4670D in terms of sound quality. The 2380 horn of the 4670 was never a good horn. It has no pattern control below 1000Hz and it is normally crossed over at 500Hz for cinema.

I like QSC's 3-way speakers like the SC-424

Posted by Steve Guttag (Member # 268) on 01-09-2015, 05:57 AM:

Sorry for the typo in the last sentence above (editing time has expired). I like QSC's 4-way speakers like the SC-424...I do also like their 3-way speakers like the SC-423 too.

Posted by Marco Giustini (Member # 4544) on 01-09-2015, 03:40 PM:

Thanks Steve,

I was not aware of those speakers. Heck, QSC are releasing new products every day!

Posted by Aleksandar Obradovic (Member # 7266) on 01-10-2015, 10:28 AM:

Hi guys, I've been a little bit busy during past few days making some plans and CAD drawings for this cinema.

@Marcel, I have started my own integrator/service company (from scratch) and this is going to be my 1st "big" job

Now, about amps... What can be of use of QSC's these days? I had good experience with ISA series(the good ol' one's) of same manufacturer and for 3y period (i had take care of this multiplex site where they where installed) no problem noted neither with QSC speakers nor amplifiers.

What are your opinions of new amps of this series? What do you think of multi-channel amps (like crown DCi 4/300N)?

BR Alex

Posted by Mark Gulbrandsen (Member # 72) on 01-10-2015, 08:14 PM:

I've done one pair of SC-424's and three pair of SC-323's. All excellent speakers. Best dialog reproduction I've ever heard in a cinema system.

Mark

Posted by Steve Guttag (Member # 268) on 01-11-2015, 11:29 AM:

From personal experience...nothing beats a QSC for cinema use. The DCA line is my favorite but the ISA does work...they are heavier, deeper and made in China though.

QSC is now promoting their new DPA line pretty heavily. One has to be thinking a little differently when using these. Think of them as a gain sharing amplifier. You have all of that power under the hood and it will split it up as needed. Kind of handy in a multi-way system where the HF and MF use MUCH less than the LF section. Also, unlike conventional amplifiers, you are not rewarded for lower impedance. So the power rating for 4-Ohm is typically the same as for 8-Ohm. As such, there is no need nor desire for a 4-Ohm LF section, necessarily. This lowers the current on the speaker wire which reduces the wire size demand on long runs (lower current). The amplifiers have onboard DSP like some other amplifier companies too.

Posted by Aleksandar Obradovic (Member # 7266) on 01-11-2015, 02:24 PM:

Here is my idea so please do not hesitate to comment on it...

1. Power amplifers QSC CXD4.2 (700W X 4 channels) - 2 pcs
2. QSC SC-1150 for L/C/R channels - 3pcs
3. QSC SB-1180 as LFE - 1pc
4. QSC SR-8101 as Ls/Rs/BLs/BRs - 8 pcs
5. Dolby CP750
6. Barco DP2K-10Sx

Main problem is space so all components must be "miniature". E.g. behind screen i will have less then 50cm (20"), room is about 65 sq meters, 3m height... As far as i am in this there is no concern bigger for me than sound engineering so client can be satisfied (and also patrons).

BR Alex

Posted by Harold Hallikainen (Member # 5405) on 01-11-2015, 04:02 PM:

From my somewhat biased position, you MIGHT want to look at the USL JSD-60 . Also, you can plug a USL CMS-2200 into that Barco 10-S.

Harold

Posted by Aleksandar Obradovic (Member # 7266) on 01-11-2015, 06:05 PM:

Harold, USL is not good option for me because of their support in my area which is none (or i am not aware of it). But i would like to have some of their test equipment [Smile]

Can you give me some prices for audio/video testing/calibration instruments like LSS-100 and PCA-100?

BR Alex

Posted by Harold Hallikainen (Member # 5405) on 01-11-2015, 09:09 PM:

Sorry to hear about the apparent lack of support in your area. I'll ask Clint to contact you about prices - that's not my department (which is design).

Thanks!

Harold

Posted by Aleksandar Obradovic (Member # 7266) on 01-15-2015, 04:42 AM:

Hi all,

Maybe some of you guys (from Europe) would like to know prices for QSC speakers so here they are (approximate):

SB-1180 = 700 euros/pc
SC-1150 = 800 euros/pc
SR-8101 = 200 euros/pc

And can someone point me in right direction for QSC amplifiers here in Europe because my supplier doesn't have them? I am actually looking to find QSC CXD4.2 (4x700W)

BR Alex

Posted by Marco Giustini (Member # 4544) on 01-15-2015, 04:04 PM:

I'm not familiar with the CDX series and I don't know the prices. I'm wondering if it would be better a non-DSP amplifier with a central, more advanced, sound processor.

Such as ISA/DCA and a JSD or maybe an external DSP.
CP750 does not support DTS over optical, which could be a huge issue if your customer wants to play a DTS disc.

Posted by Carsten Kurz (Member # 5396) on 01-15-2015, 04:30 PM:

Add a 60€ BluRay Player from Samsung which allows to recode DTS to DD, and the issue is solved. Not that I'm a CP750 fan...

- Carsten

Posted by Aleksandar Obradovic (Member # 7266) on 01-18-2015, 12:39 PM:

Guys i will be more than happy to install JSD series audio processor from USL but main problem is that i can not find them somewhere near to me. Fortunately guys from USL have contacted me and now we are talking about some kind of collaboration and so i will probably be able to get my hand on it but not for a while. Until this i have to solve this in old way with equipment i have in reach.

Maybe this time next year if everything would be as planned i will have all of it at my warehouse and at my disposal at any time. For now i have to do some magic.

BTW have someone of you had some experience with Behringer ECM8000 mic? I have never used it for calibration but i have heard that is is very good for this job. Point is that i can get it for small price and i am considering to buy it.

BR Alex

Posted by Marco Giustini (Member # 4544) on 01-18-2015, 03:17 PM:

get a Beyerdynamic. They are actually checked and won't fall apart on you after 2 years.

Posted by Mark Gulbrandsen (Member # 72) on 01-19-2015, 01:25 PM:

Good grief! Skip the CP-750. The thing is ancient and they are having major power supply issues with them. I remember seeing the first ones installed way back when I worked for CLACO around 2006 or 2007. It's old stuff now. The JSD-60 is a much newer design and has much superior DAC's in it.

Mark

Posted by Carsten Kurz (Member # 5396) on 01-19-2015, 01:48 PM:

There is actually a german site that shows statistics over thousands of calibration microphones -the vast majority cheap ones like the Behringer 8000.

Indeed, the Beyerdynamic is the only low-to-medium-cost device which offers good repeatability out of the box.

https://www.hifi-selbstbau.de/grundlagen-mainmenu-35/softwaremesstechnik-mainmenu-66/480-1000-mikrofonkalibrieru ngen-eine-uebersicht

Look at the graphs for ECM-8000 and MM1!

The company maintaining the site offers to calibrate all mics and deliver calibration files for them. But not every techs tools can deal with these files, so it is certainly better to get a Mic that shows a higher level of confidence.
That said, we should know now that classic EQ-style room measurement and calibration sucks, and a better calibration mic doesn't help with that.

- Carsten

Posted by Steve Guttag (Member # 268) on 01-19-2015, 01:51 PM:

Sorry Mark...we're not having CP750 issues and it is good sounding/reliable processor that can switch decode modes on the fly without having to create "user preset" buttons. While I have not done any sort of exhaustive listening test...I have yet to hear a JSD sound favorable to a CP750.

Both line ups have their ups/downs and are worthy of consideration.

Posted by Marco Giustini (Member # 4544) on 01-19-2015, 03:07 PM:

quote: Mark Gulbrandsen
The JSD-60 is a much newer design and has much superior DAC's in it.

While the JSD60 seems a nice product, the 750's DACs are definitely less noisy. The JSD60 is a budget product, I'm happy with that, but it's unfair to say its DAC's are better than the 750's.

Carsten,
Interesting. Each MM1 microphone comes with a sheet and a custom graph, Beyerdynamic claims the mike has been tested and it's +/- 3dB I reckon.
According to the website you linked, basically every microphone they tested had a boost at high frequencies? Every single one of them?

Posted by Carsten Kurz (Member # 5396) on 01-19-2015, 04:15 PM:

Marco - you will probably have a hard time understanding the accompanying text - basically the graphs are all set for a 0degree mic positioning, and at high frequency, mic response has a strong directional factor.

Their preferred way of measuring stereo and surround systems (not individual speakers) is at an 90degree angle, pointed up. In this orientation, the response is much flatter. ProMics usually come with a polar diagram also depicting this.

See: https://www.hifi-selbstbau.de/images/stories/grundlagen/hallraum2/MicCalDeg.png

When you send in your mics to them, you can tell them to use either positioning or both for the calibration.

Also, some mics (usually the DIY capsule types) have been supplied for calibration by their owners including their preamp/USB-A/D, so they would be factored it.

- Carsten

Posted by Marco Giustini (Member # 4544) on 01-20-2015, 01:55 PM:

Thanks Carsten,
My German is indeed rusty.
Forgive me for my scepticism, I've sent microphones to calibrate before and I've never been very impressed by the results to be honest. I feel that every person had a different approach when calibrating a mike.

Posted by Marin Zorica (Member # 1716) on 01-21-2015, 03:06 PM:

There is not much to say about choice, choice of speakers is good. But one other thing i like, when there is anought space- in rack is to use two channel power amp.....if anyway one fails you have four channels dead, is two channel power amp, in case one fail,- you can always say switch to other and leave surrounds off.
As for CP750, newer hear for that power supply problem, tought, i wouldn't be too suprised, since CP650 power supply was basily same like PS from sat receiver [Big Grin]

As for behringer mics....i know some they used it since it's cheap, and one time i have colegue which also graduated in electroacustic, he told me they did compare that behringer ECM to bruel&kjaar in dead chamber, and that ECM is great, that offseet (calibration) is not so big, just 1-2dB on some freq......like i said, i hear that.

Posted by Avi Bm (Member # 8776) on 03-21-2015, 02:47 PM:

Hi Aleksandr
what's your verdict on the qsc 1150?
I have to choose between qsc sc-1120 to
Jbl 3677. The 1120 uses a 12'' driver.

My room is small only 16×21×86ft (5×7×22.52.5m)

As part of 7.2.4 Atmos in my living room.
Will use these with 4 SR 8101 and sb 1180

Room will be acousticaly treed with baffEl wall in front and speakers behind AT screen