Film-Tech Forum ARCHIVE: Speaker Recommendations

This is topic Speaker Recommendations in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Mike Frese (Member # 4361) on 06-11-2010, 08:05 AM:

I have a small room: 32' deep, 25' wide, and 14' H.

For the front speakers (Left/Center/Right), would the JBL 4647 with HF horn http://www.jblpro.com/pub/obsolete/4647.pdf be a good choice? Or JBL 3000 series? 3677 especially? http://www.jblpro.com/catalog/General/ProductFamily.aspx?FId=31&MId=1

Processor for now will be a smart mod IIc in SR with the idea of upgrading in the future. Using QSC DCA and ISA amps.

Thanks

Posted by Demetris Thoupis (Member # 833) on 06-11-2010, 08:42 AM:

I would prefer none of the above. The 4647 with HF horn would surely be an overkill for the size of room. I would prefer the 3678 bi-amped if possible with one 4165c subwoofer. Even the 3678 in passive mode is better selection although more expensive. Room is quite small. 9meters x 7.7 approximately so not much need for anything fancier. Also the KCS 1801 is an excellent performing speaker for your application. Try and go bi-amp if you can. If you can afford DCA amps or ISA then push that extra step. Additionaly the JSD-80D unit from USL is a much better performing processor than then Smart Mob IIB and not only that, it is futureproof as it is D-Cinema ready. My opinion is if you will do the job, do it right from the first time.
Demetris

Posted by Don Furr (Member # 1469) on 06-11-2010, 09:53 AM:

My room is 20X15 and I'm using the 3678's for stage speakers and the 4645C sub. I think the 3000 series would be plenty of sound in your space. Of course you'll get as many opinions as people who reply to this post!!!

Don

Posted by Marin Zorica (Member # 1716) on 06-11-2010, 10:27 AM:

Definitely 4000 series is to big for the room you have, if you have money take 3678 with sub and surrounds from 3000 series, but also, if you're lower on money, go to KCS's, I used S1800 in one cinema not so long ago, they performed so well for money, normally as usual BI amp is always better.....but requesting crossover or processor with, and aditional amps.

Posted by Steve Guttag (Member # 268) on 06-11-2010, 01:10 PM:

Are you people nuts? The 4647A is just a single 15" system and you think it is overkill? Turning the 4647A into a 4673 would be an excellent choice. I'm not the biggest fan of the 3000 series stuff...they are not too smooth at crossover.

Steve

Posted by Mike Frese (Member # 4361) on 06-11-2010, 03:28 PM:

I already own the Smart Mod IIc, it came with a bunch of stuff that I bought.

Looking at the specs. the 4647 seems pretty close to the 3677. I am leaning to the 4647s since there are a few used 4647s out their at half the cost of buying new 3677s.

I will keep my eyes open for some 4673s. I need these pretty soon though, so may not be able to wait.

Posted by Steve Guttag (Member # 268) on 06-11-2010, 04:15 PM:

The 4647A is JUST the bass system...not a complete speaker! To make them into 4673s you need to combine them with a 4670HF system and, for passive, use a 3115 crossover.

Steve

Posted by Mike Frese (Member # 4361) on 06-11-2010, 05:07 PM:

Yes, I know. Looks like the 4647 is the LF part of the 4671 and 4673. Looks like the 4670s use the same HF driver, with 3 different horns to form 4 different systems? Also seems the 4671 is recommended by JBL for smaller rooms. That big of a difference?

Posted by Demetris Thoupis (Member # 833) on 06-11-2010, 05:38 PM:

In theory it is better to have the speech coming from a single point of the speaker. In the 4671 the speech will be divided between the LF and HF of the speaker since it crossovers at 800 HZ and speech supposedly is from 500Hz and above. The benefit you have with the 4673 is that you have less problems with phasing since the HF section is crossovered at 500HZ and thus all speech is derived from there. That being said, ms time delays are there to better eq the phase difference created by the LF and HF. That is the reason the 4673 has a bigger horn since both 4671 and 4673 beam coverage is 90 degrees. If those are your choices I would think the 4673 is better and I would not even touch the 3677. All these solutions though lack the very low frequencies of 20-30Hz which kick a bit when needed to create that booming effect in addition with the subwoofer but these speakers frequency range is from 40Hz and above.
Demetris

Posted by Louis Bornwasser (Member # 3063) on 06-12-2010, 09:18 PM:

I just don't think any cinema is too small for 2 woofers and a decent horn. This is not about size/quantity. It is about quality. Louis

Posted by Steve Guttag (Member # 268) on 06-12-2010, 09:37 PM:

I definitely disagree with you there, Louis. A speaker can be too big for the screen...the sound will be unnaturally large and as the components are spaced further apart, one has to be further away from speaker for proper convergence of the various components. Why do you think the 4647A offsets the driver high in the cabinet? Likewise, the A7/A5 also offset the horn high...one wants to keep the system as close to a point source as possible.

The 4647 was also a VERY good box (4507) and the bass was notably tight and clear.

Steve

Posted by Tony Bandiera Jr (Member # 2365) on 06-14-2010, 04:23 PM:

Mike, you're already doing a QSC "front end" so save a lot of grief and get the best sound for the buck and go with the QSC Digital Cinema Series speakers Speaker Home page.

I just installed the three-way systems THESE (run bi-amped) in my new room at UC Irvine (95 seats) and they sound great, were easy to align and EQ, and the price point was favorable compared to JBL. I used the SB-5218 with them. Subwoofie

Contact Bevan Wright at Moving Images Technologies and he'll get you set up nicely.