4344 L-pad adjustment need advise

[hoto]

I finally have time to play around the 4344. noticed that one channel is slightly louder than the others, so not able to get the exact center image... I started to adjust the 3 knobs on the front and noticed that some interesting points and need forum members's advise.

1. the reading on the 4344 foical is difference, I mean when I turn the knobs all the way up, it never go to the +6db marks on the foical, it only goes to the +5.5db, I think it just happen because when they glue the foical not really pay attention to the reading/mark.But one speaker's focial match exactly when tuning.

2. Since the READING is not the same on the speakers, I manually adjust the knobs to match the others. (e.g. left speaker is 0db (middle),right speaker turn to middle as well but READING is -0.5db )

3. If i do the step 2,means the SAME setting on both speakers, the RIGHT channel is slightly louder than the LEFT.

4. Once I adjust the knobs on the RIGHT speakers (means -2db on the knobs, )then I get the perfect /balance sound fr both speakers and able to create center image.

5. Speaker placement is very hard for the 4344, is that right?

Summary:
Queation:

**Is that normal to have different L-Pad adjustment on EACH speaker or must do as a PAIR??

**-2db on one channel to get the balance sound is acceptable?

Thanks for the helps.

Tom

[Chas]

It's not likely that you can expect the foilcal marking positions to match, the L-pads and driver sensitivities have a fairly wide tolerance. No doubt the L-pads are the worst offender, here.

I would recommend:

A/ Do a search here and study Ian's and Bo's postings about 4345 set up, it would be relevant for all 434X series.

B/ Get an RTA to at least, give you a benchmark idea of the MF/HF/UHF levels relative to the woofers. If you haven't got an RTA, I might be persuaded to drop by with one :) - although I will be away for a couple of weeks.

C/ Or, simply do it by ear. This is not as easy as it sounds, especially when bi-amping, since this can also complicate things somewhat.

[Robh3606]

What do you have as measurement tools?? Do you have an SPL meter?? You can download free RTA software but you would need a measurement microphone and a phantom supply to run it. You might want to look at a battey powered phantom supply and the Behringer Measurement Microphone. You can use your sound card microphone input's to interface with the software. You can also go the SPL meter route but you need to make sure you can get a copy of any correction curve for the inexpensive ones. Radioshack has a couple of models an analog and a digital. The more common models have correction files readily available if you search for them on the internet.

http://www.hometheatershack.com/forums/downloads-area/19-downloads-page.html


I set mine up with an RTA.

Rob:)

[hjames]

The L-pads are mounted on a separate wood "sub-panel" that is held against the back of the front panel with phillips screws (hidden under the foil-cals). The L-pads are kind of like volume controls - metal "cans" with an adjuster shaft sticking out the front, and are held on the "Sub-panel" net with nuts that go around the shaft to clamp the lPad body against the subpanel. The marker dot you see from the front is on a knob that slides onto the L-pad shaft. If the nut isn't tight enough or the L-pad turns (slipped) slightly on that panel, the "Wide Open" and "full-cut" extreme settings will no longer match the high and low marks on the foil cals. Accessing the L-pad sub-panel means getting removing the foilcal to access the hidden screws that hold the panel against the baffleboard and (probably) removing the big woofer to go inside the cabinet - Its kind of a big deal if you know what you are doing and its something a novice may not want to do to a working speaker system. You might just want to set them where it sounds good and not worry about what number the pointer is on ...

If you do decide to "do it right", getting levels correct may also involve rebuilding the crossover, and checking/replacing and driver diaphrams that are not correct or have been changed for non-stock parts in the past. Getting the speaker in correct working order means making sure all parts of the speaker are working correctly as designed - its what the hot-rod car community would call "blueprinting" the system, changing out of spec parts for the correctly performing parts.

I don't mean to insult if I over-explained this - I'm not sure how technical you are or what tools you have to check and set levels.



I finally have time to play around the 4344. noticed that one channel is slightly louder than the others, so not able to get the exact center image... I started to adjust the 3 knobs on the front and noticed that some interesting points and need forum members's advise.

1. the reading on the 4344 foical is difference, I mean when I turn the knobs all the way up, it never go to the +6db marks on the foical, it only goes to the +5.5db, I think it just happen because when they glue the foical not really pay attention to the reading/mark.But one speaker's focial match exactly when tuning.

Tom

[hoto]

Hey
thanks for the infos again, I am not a DIY person and really need your clear explanations.
I am not going to do anything now and just adjust the knobs to the balance level.

[Ian Mackenzie]

It's not likely that you can expect the foilcal marking positions to match, the L-pads and driver sensitivities have a fairly wide tolerance. No doubt the L-pads are the worst offender, here.

I would recommend:

A/ Do a search here and study Ian's and Bo's postings about 4345 set up, it would be relevant for all 434X series.

B/ Get an RTA to at least, give you a benchmark idea of the MF/HF/UHF levels relative to the woofers. If you haven't got an RTA, I might be persuaded to drop by with one :) - although I will be away for a couple of weeks.

C/ Or, simply do it by ear. This is not as easy as it sounds, especially when bi-amping, since this can also complicate things somewhat.

yep,

The tolerance of those L pads is crap ..and that is being polite.

So any of ya who uses the markings is wasting your time

Assuming the voltage drivers for the Xover are correct the subtractive methed of -x bd using a spot near field ( 5 cm) sine wave on each driver (of each channel) yields the flatest (RTA ) response every time. Game over Man, Game over.

[porschedpm]

This is a link to Ian's method of setting L-Pads on the 43XX monitors. You'll need an SPL meter. It works.

http://www.audioheritage.org/vbulletin/showpost.php?p=60625&postcount=7

[Ian Mackenzie]

It works best when your wearing a JBL shirt (authorised adjustment!)