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greyhound
07-31-2011, 07:22 AM
hello...im back form being distracted by another audio brand...but rest asured...im here to stay.
so hello again to anyone who can remember me.
i bought a pair of 4312a monitors and i was wondering what do the 2 controls..how you call em...potmeters?
that control high freq and low freq output?
is it so that when i turn them down to zero...i hear the speaker as it normaly sounds?
as it should sound?
or do i hear the speakers full potential only when i turn em way up?

so does anyone know what the controls do exactly?

kind regards
robin

and it realy feels good to be back here...i wondered off the path way to long

hjames
07-31-2011, 07:27 AM
Welcome back, good to have you here!



hello...im back form being distracted by another audio brand...but rest asured...im here to stay.
so hello again to anyone who can remember me.
i bought a pair of 4312a monitors and i was wondering what do the 2 controls..how you call em...potmeters?
that control high freq and low freq output?
is it so that when i turn them down to zero...i hear the speaker as it normaly sounds?
as it should sound?
or do i hear the speakers full potential only when i turn em way up?

so does anyone know what the controls do exactly?

kind regards
robin

and it realy feels good to be back here...i wondered off the path way to long

greyhound
07-31-2011, 12:09 PM
thanks....ill never leave again...i realy missed jbl
i missed the dynamics...the power...the real live sound.....i have to admit that my spendor studio monitors gave me lots off pleasure...but they are a bit dull

had to sell the gold centuries due to financial problems.
didnt get the chance to hook these 4312's up yet

ill do it tomorrow

Don C
07-31-2011, 05:07 PM
Start with the controls at half way up and then adjust to suit your own taste and room acoustics.

greyhound
08-01-2011, 12:00 AM
yep...thats about the same way i planned to do it...i was going for turning way down and work my way up.

but im interested in what happens when i turn em up. technically

is there a users manual for download somewhere?

greyhound
08-01-2011, 07:08 AM
and does anyone know the max Dba output?

greyhound
08-05-2011, 12:03 AM
well i didntknow my questions were:
a) to difficult
b) not much of a challenge
c) boring
d) been there done that got the link for you.....
e) none of the above

;)

greyhound
08-05-2011, 05:10 AM
i'll also have to take the x over out because of scratching potentiometers...ive found the audiokarma link
so im afraid ill have to use a blow dryer and a spatula

grumpy
08-05-2011, 07:06 AM
Dba?

http://www.jblproservice.com/pdf/Studio%20Monitor%20Series/4312LR.pdf

Breaking it down to just a single number isn't necessarily all that informative, but
a brief look at the specs gives an indication:

91dB sensitivity + 200W (program) => 114dB SPL @ 1m

probably more peak capability in some frequency regions and less in others...
as well as losing some ultimate level capability due to power compression
(stuff gets hot and loses sensitivity)

Don C
08-05-2011, 08:45 AM
E) Tedious and pointless. Just turn the knobs and see what they do, and turn up the volume and see if it's loud enough for you. You want a number for how loud they'll play? Why?



well i didntknow my questions were:
a) to difficult
b) not much of a challenge
c) boring
d) been there done that got the link for you.....
e) none of the above

;)

grumpy
08-05-2011, 09:13 AM
that was my kneejerk reaction... then I set it aside for a bit. :)

A minor distraction from world events is useful now and then.

greyhound
08-05-2011, 09:33 AM
thank you gentleman.

in reaction...i didnt ask what the controls did "sonically"
then i would agree...i asked whet they do technically.

so for example...is it so that i hear the speakers natural sound when i turn em all the way up?
is it just a capacitator ( or how you call them) that builds resisitance as i turn the knob?
so does this mean the potentiometers are 0 resistance when fully open?


second question was because of the fact that i have a big amp. a friend of mine built something inside (like a safety) in 1 channel.( like a rothwell attanuator)...and the other channel is original.

my last speakers couldnt take more than 105 Dba so i had to be carefull not to blow them ( only when im fooling around in the livingroom, dancing with the kids and all) so i wondered if there would be any chance whit this speakers...but with 114 Dba...we all go deaf first.

so thank you for the answers.
tonight im gonna try to remove the filters and clean the meters.


im sorry if my reaction was tedious ( had to look it up) it was not my intention

grumpy
08-05-2011, 09:45 AM
The newer -A model adds an inductor to roll off the tweeter more rapidly, but
the knobs simply adjust how much power makes it to the mid and tweeter,
while making the 'network side' still see ~8 ohms (or the nominal L-pad operating value
... some are 16 ohms). That way, the crossover points do not shift as the knobs are
turned.

http://www.jblproservice.com/pdf/Network%20Schematics/3112D%20Network.pdf

Turning it all the way up allows for maximum power to pass.
Turning it all the way down absorbs the power in the "L-pad" attenuator
(that the knob controls). The amp won't see much difference, if any.
Nominally, a design will use the midpoint of such an adjustment for 'normal'
or 'flat' use.

I suppose you have some sort of sound level meter, hence the concern with dBA?
I'd be more concerned about my ears... which, by the way, are a fair indicator
of when to turn the volume down (if it sounds different, hard, or distorted, ... turn it down).

greyhound
08-05-2011, 09:51 AM
yes i have a dba meter...

i dont play very loud when im listening to music...but i have kids that have turned the volume up before.
you can tell em "dont"...but i know how i was when i was a kid ;)

but the speakers are safe now when you turn it all the way up.
its just 1 worrie less.

thanks
kind regards
robin



not on the carpet dude....it realy tied the room together.:D