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JoeStrange
09-04-2006, 11:04 AM
Hey guys,
I was fortunate enough to find a pair of near mint JBL 4435's recently,They had been refoamed in the past 5 years and are ready to rock.

Now I have never setup anything like this before...Im a recording engineer not a tech,But this job has been thrown on me so I gotta come up with anwsers for the studio owner. I purchased 2 Crown k2's to power the 4435's and I want to bridge each amp which I have no idea how to do.

I also need to know what gauge speaker wire im looking for and what I need to bridge each amp. I was looking at canare 14 gauge? Am I in the ballpark?

So again heres my 2 questions simplified:

How do I bridge 2 Crown K2's to power the JBL 4435's (1 k2 a side)

What speaker cable should I be using? IE. Brand and Gauge.

Zilch
09-04-2006, 12:03 PM
So again heres my 2 questions simplified:

How do I bridge 2 Crown K2's to power the JBL 4435's (1 k2 a side)

What speaker cable should I be using? IE. Brand and Gauge.The K2 manual doesn't tell how to connect them bridged?

Frankly, I cannot conceive that 4435s would require that much power. Look at the specs for recommendations. I'd just take one of the K2s home. ;)

Wire? Unless its a run more than 25', it's Radio Shack 14 ga. here. Your amp manual will have recommendations for different lengths, most likely....

speakerdave
09-04-2006, 12:13 PM
Hey guys,
I was fortunate enough to find a pair of near mint JBL 4435's recently,They had been refoamed in the past 5 years and are ready to rock.

Now I have never setup anything like this before...Im a recording engineer not a tech,But this job has been thrown on me so I gotta come up with anwsers for the studio owner. I purchased 2 Crown k2's to power the 4435's and I want to bridge each amp which I have no idea how to do.

I also need to know what gauge speaker wire im looking for and what I need to bridge each amp. I was looking at canare 14 gauge? Am I in the ballpark?

So again heres my 2 questions simplified:

How do I bridge 2 Crown K2's to power the JBL 4435's (1 k2 a side)

What speaker cable should I be using? IE. Brand and Gauge.
You may have a superfluity of headroom there, so one K2 connected normally will certainly get you up and running.

Congratulations on the acquisition--and welcome to the forums!

David

JoeStrange
09-04-2006, 01:29 PM
I have no manuals for the crown k2's...I bought them used.

I did the spec work and cant remember what the power rating @ 8 OHMS on the 4435's was, but I came to the conclusion that 1 crown k2 will underpower them @ 8ohms and we cant have underpowering because that blows speakers, so I decided to go with 2 crown k2s bridged to fulfill or exceed the maximum power rating.

Radio shack cable for a commercial recording facility would be out of the question in my mind.....Any gauge reccomendations? The speaker cables will be around 20 feet maybe more. Im under the impression that the larger the gauge the cleaner the current flow....Is that right?

JoeStrange
09-04-2006, 01:51 PM
Ok,
I downloaded the k2 manual from crown that anwsered both of my initial questions.

Heres a new question for you guys.

Who knows for sure what the power rating of the 4435's is?

CROWN K2:

2 ohm stereo (per channel) 1,250W
4 ohm stereo (per channel) 800W
8 ohm stereo (per channel) 500W
4 ohm bridge-mono 2,500W
8 ohm bridge-mono 1,600W




Specs from JBL- JBL 4435's:
Recommended Amplifier Power,Biamplification @ 8 OHM
Low Frequency: 400 w

High Frequency: 150 w



But it also says max power input 375w,This is where it gets confusing for me...How much can the 4435's handle.....whats the peak rating?


I got 2 crown k2's cause I was for some reason under the impression the peak was over 700w.


4435 specs from JBL here:
http://www.jblpro.com/pub/obsolete/443035.pdf

Zilch
09-04-2006, 02:05 PM
4435 is 96 dB, 1 W @ 1 m. Recommended LF biamp power 400 W, the big load.

http://www.jblpro.com/pub/obsolete/443035.pdf

K2 is 500 W/channel into 8 ohms.

JoeStrange
09-04-2006, 02:19 PM
So is 1 crown k2 more than enough power to power both JBL 4435's?

Zilch
09-04-2006, 05:35 PM
It would seem so, yes.

I just don't see much point in using four times the recommended power, instead....

grumpy
09-04-2006, 07:54 PM
Opinion/FWIW:

I'd find out the largest gauge of wire that would fit your speaker terminals
and go from there... they're not huge. I'm sure canare would be fine ... I've
got 4-wire mogami on my 4430's when I bi-amp.
I've not heard a significant improvement trying anything else on a run so
short (others obviously think they have, and it may be so).
Your studio customer may have a preference.

Regarding the powering situation... I'd biamp and use the k2's without
bridging them... would need a dedicated external electronic crossover
to emulate the 5234a or 5235 + cards with slopes designed to work with
the 4435's ... worth spending some quality time in the "Library" here.
Perhaps later suggest to the studio a smaller sledgehammer on the high
end as a refinement/upgrade, if they have any issues in the top octaves.

My only real concerns in using the K2's full-range in bridge mode are
in terms of audio quality... I'm sure they'd still bang out plenty of bass into
the few ohms presented by the paralleled 2235H's (ok... + L&R) and
you -might- get a few dB more in peak volume... but why? You'd already
likely be in the realm of permanent hearing-loss in a studio environment.
Make the job easy for the amp and it will likely reward you :D

(wow.. LOTS of opinion in this post :o: )

-grumpy

JoeStrange
09-04-2006, 08:49 PM
Thanks for your help zilch....really appreciate it man.

Grumpy,
Thank you for getting in on this. Yea I have already been exploring bi-amping the 4435's and adding a crossover but I was looking at 2 bryston amps for the hi's and mids and using just the K2's for the lows.

Who knows what will end up happening? What I do know is im going to have to find a use for that second k2 or im going to look like a jacka$$ for over spending 800 bucks on somthing we didnt need. So I'll probly just take your advice grumpy and look into a crossover.

BMWCCA
09-04-2006, 08:52 PM
Put 'em both in the rack, have them both power-up. Only hook up one to speakers. In a professional setting you always must plan for any eventuality. Double redundancy is certainly justified in amps. (Not really, I'm just trying to help!)

Zilch
09-04-2006, 09:05 PM
I'll have my nephew in Michigan pick up the second K2 from you.

He'll send it to me.

I'll test different wire gauges and types with 4435s using it and write a thorough report of my findings for your client upon completion.

There'll always be new wires to test.... :p