First Listen - 4430s.

[sfellini]

Hello again everyone -

I've been listening to the 4430s for about a week now and
have a few comments and questions. I'm driving them
with an MC2120 amp.

So far, I've been listening mostly to jazz, and on most CDs
they sound really fine. First rate dynamics and instrumental
timbres are true. Imaging isn't particularly important to me,
but they are fine there too. Bass sounded boomy on some
jazz trio recordings, but going from the 8R to the 16R tap
on the McIntosh amp fixed that.

Now the bad news: I noticed problems immediately with
classical music. There is a lack of orchestral "bloom",
which usually means a suckout in the bass frequencies.
(I've had the problem before with other speakers in
other rooms). I used a simple Radio Shack meter and
test warble tones to try to see what was going on.

Which is: over 10 dB down around 50 Hz and 60 Hz, depending
on positioning. I tried moving both speaker and listening
positions forward and backwards, but would always get that
suckout at one or the other, or both frequencies. This is a
bummer, as replacing the room would be somewhat expensive .
The room is 20' x 13' x 9' (and opens into a kitchen area).

Any help or suggestions would be much appreciated.

Thanks,
Steve.

[JBLnsince1959]

Steve:

when you tested this were you on the 8 or 16 tap? if you were on the 16 tap go back to the 8 and test again ( there are better ways to get rid of bloomy)

[JBLnsince1959]

The one thing I learned MOST about the 4430's is this: they will sound whatever you give them( more than most speakers). Hook them up to a MAC and they sound like a MAC, hook them up to a marantz and they sound like a marantz, mark levinson, aragon etc. My marantz MA700's worked great for "tightening up the bass"

Also, the wires and interconnects will also make a difference in the way it sounds.

Botton-line is that when things don't sound the way we want them to ( or worst, what we've been use to), we tend to blame the speakers and fight with them instead of learning to work with them. I personally did not have that type of drop with mine.

try putting it back to the 8 tap ( if you haven't done so) and try different amps if needed.

also the Mac 2120 may not be the best ( or the best MAC) for the 4430 with it's Damping factor of 14. Mac's will have a very full bass compared to some other amps, which can sound bloomy on the 4430 if not setup right or corrected by such means as building stands( geting them off the floor) or retuning, or stuffing

[JuniorJBL]

look also at your transport (CD player) and pre amp as well. these things can add thier "own" sound. If your transport has a digital coax out try an outboard DAC.

I just had a demo with a Musical Fidelity KW500 and was blown away by the pre amp that is part of this unit. It made my adcom GFP-750 sound like an Emmerson all-in-one stereo. I also had a demo of a musical fidelity X-DACv3 and it had a nice affect on my denon 3910 dvd player.

as it has been said here speakers are not always the problem. They can tend to show you the weekness of other components tho (4430 is a good example of this)

my 2c

[JBLnsince1959]

look also at your transport (CD player) and pre amp as well. these things can add thier "own" sound.

as it has been said here speakers are not always the problem. They can tend to show you the weekness of other components tho (4430 is a good example of this)

my 2c

10-4..... the 4430's were my best speakers to "hear" the differences of different components. also, the secret with these puppies is patience

[Mr. Widget]

Electronics? Wires? ....well yeah sure, but start off by looking at the problem. You are probably right to think of the room and placement. The bass suck out is definitely a room mode issue. Try placing the speakers diagonally in the room.

Another issue is that the stock 4430 has the classic JBL bass bump. The tuning of the ports is a bit high. If you lower the tuning a bit you will get a more extended and more natural response. If you do some "searches" you will find info on this.

Widget

[JBLnsince1959]

Electronics. The bass suck out is definitely a room mode issue. Try placing the speakers diagonally in the room.

Another issue is that the stock 4430 has the classic JBL bass bump. The tuning of the ports is a bit high. If you lower the tuning a bit you will get a more extended and more natural response. If you do some "searches" you will find info on this.

Widget

I agree ( under normal circumstances)... however, he mentioned that he switched the taps and that changed the bass and now he doesn't have enough with some music. So it seems logical to get the bass back to where is was ( 8 tap) and then work with room placement and tuning. If the 16 tap has made a difference ( as he said it has), seems like the first place to look and then test again.

[Mr. Widget]

Sure, it would be a good idea to also try any competent SS amp and see how it behaves. The transformer coupled amps can be problematic with JBLs.

That said, rooms and room placement play a huge roll in LF performance.

Widget

[JBLnsince1959]

The transformer coupled amps can be problematic with JBLs.

That said, rooms and room placement play a huge roll in LF performance.

Widget

10-4...I was just wanting him to undo ( if he hadn't done it already) what he did and get the bass back to where he started and then measure again.

I had the same problem with my 4430's ( I didn't change the tap tho, so I don't know what that would do) at first. Room placement and getting them off the floor did the trick for me.

[sfellini]

I agree ( under normal circumstances)... however, he mentioned that he switched the taps and that changed the bass

Thanks for the suggestions so far...

Let me qualify what I said - changing the taps changed the character
of the bass, not the frequency response. I did do the frequency response checks with both the 16R and 4R taps: both had the 50/60 Hz suckout.

[edgewound]

I agree with Widget...sounds like an acoustics problem. Have you ever had speakers of this size in your room? What's it sound like in an adjacent room? Move yourself around the room while classical is playing and maybe you'll fine a "hot spot" of bass....then move again and maybe you'll find the "suck out" problem. You might have to resort to bass traps to fix your room...or some other acoustics treatment...or simply moving the speakers might help....just some thoughts


Edgewound

[Mr. Widget]

Have you tried radical changes in room placement? Getting them off the floor will definitely smooth out the bass but will also reduce the bass below around 80Hz.

Widget

[JBLnsince1959]

Thanks for the suggestions so far...

Let me qualify what I said - changing the taps changed the character
of the bass, not the frequency response. I did do the frequency response checks with both the 16R and 4R taps: both had the 50/60 Hz suckout.

knowing that then it sounds more like room placement or some other fix is needed.

did it do the same with the 8 tap?

[edgewound]

As an aside...but I think relevant here...Most recording studio monitors of this size are soffit mounted....way off the floor, and surrounded by soft, padded walls...in other words... a dead room. When they're on the floor, and/ or in a corner, you get a 3-6dB increase in most everything below 100Hz, and that includes the associated room peaks and nulls that go with it. Maybe we're throwing out too much info...lol.


Edgewound

[Zilch]

The JBL LSR RMC Room Mode Correction User Guide has an interesting exposition of these problems and potential resolutions. Response dips due to floor reflections are most prominent, occurring between 50 and 90 Hz.

"The dip, if it is severe, must be corrected through rearrangement of loudspeaker and listening positions."

EQing out any boundary boost between 40 and 60 Hz may help smooth it out, as well. Move 'em away from the walls.

I've never had a problem with 4430's. I plunk 'em and play 'em, always to great satisfaction.

Try a different amp, SS, preferably.

If you elevate them substantially, turn 'em upside down, as JBL recommends.

As a last resort, trade up to 4435's....