JBL 16 Ohms L-pad

[spirou38]

Happy new year everybody :wave: .

I'm looking for 2 JBL 16 Ohms L-pad for my 4333A but can't find any in France :crying: .

Is there anybody who knows where I can find those parts :confused: ?

Or is there a possible adaptation of a 8 Ohms with an additional 8 Ohms resistance :idea: ?

Thank you.

Pascal

[4313B]

I'm trying to find another source as well (with 1" shafts). I cleaned JBL out of their remaining stock.

[Guido]

I believe I can still have them from JBL Pro here.
They are expensive! I believe > 20Euros. Should I try it?

[macaroonie]

These are 16 ohm 30 watt from 3114 network. Pm me if you need them

[spirou38]

I'm trying to find another source as well (with 1" shafts). I cleaned JBL out of their remaining stock.

Hello Giskard,

Happy newyear.

Thank you for your answer. As Guido is closest from France, don't worry for those 16 Ohms l-pads for the moment. I will keep you informed if Guido doesn't succeed in getting them.

Best regards.

Pascal

[spirou38]

I believe I can still have them from JBL Pro here.
They are expensive! I believe > 20Euros. Should I try it?

Hello Guido.

Happy newyear.

Of course you can try :applaud: Please keep me informed.

Many thanks.

Pascal

[spirou38]

These are 16 ohm 30 watt from 3114 network. Pm me if you need them

Hello Macaroonie,

Thank you for your answer and happy newyear.

As I answered Giskard, Guido is closest from France, so don't worry for those 16 Ohms l-pads for the moment.

Best regards.

Pascal

[Guido]

:shock: 37 Euro EACH! :eek:

[spirou38]

:shock: 37 Euro EACH! :eek:

Ooops :blink:

Parts from JBL Germany seem to be as expensive as from JBL France :( ( but that part is discontinued in France ).

I think I will ask Giskard if he has a cheapest solution !

Thanks for your inquiry.

[boputnam]

One should ponder all the ramifications given these three impedance curves...:eek:

The Red curve confounds me - I would have thought "wide open" to have the least impact, yet the impedance spikes. I guess I pick Green.

Yikes...

[macaroonie]

They are still here at no big cost I have no use for them. May cost you a nice bottle of something from La France. Allez Allez

[4313B]

They are still here at no big cost I have no use for them. May cost you a nice bottle of something from La France. Allez AllezCan't beat that deal. Do it. :)

[spirou38]

The spikes are because there aren't any shunt resistors in the circuit while the L-Pads are wide open. Green looks good but the 4355 network is "looking" for the yellow curve in post #10. Which is actually "ok", higher impedance means smaller network values and that means lower cost.
You can try replacing the 16-ohm L-Pads with 8-ohm L-Pads and then put a 4 ohm series resistor in front of the 8 ohm L-Pad. Here I used a 4.7 ohm because it's all I had laying around within easy reach.

Red = 2421B 2307 2308 with 20 ohm shunt 16 ohm L-Pad at 50 percent.sini
Green = 2421B 2307 2308 with 20 ohm shunt 8 ohm L-Pad at 50 percent and 4.7 ohm series.sini

Hello Giskard,

Thank you for those very interesting tests and explanations :applaud: .

[spirou38]

They are still here at no big cost I have no use for them. May cost you a nice bottle of something from La France. Allez Allez

Hello Macaroonie,

Very nice proposition :D .

I just discovered that you also are living close to France :crying: .

I send you a private mail.

[Bruno GINARD]

Hello SPIROU 38

I've bought the 100 watts models / 16 ohms directly on Parts Express web site

THey have a 20/20 service !

http://www.partsexpress.com/webpage.cfm?&WebPage_ID=3&filter=l+pad&sm=1&so=1

Good luck !

[spirou38]

Hello SPIROU 38

I've bought the 100 watts models / 16 ohms directly on Parts Express web site

THey have a 20/20 service !

http://www.partsexpress.com/webpage.cfm?&WebPage_ID=3&filter=l+pad&sm=1&so=1

Good luck !

Hi Bruno,

I previously had a look on their web site but they don't have the 1" shaft model that is suitable for the 4333A, they just have the 3/8" :thnkfast:

I sent them an email asking for the 1" and they can't get it :(

[Guido]

Hi Bruno,

I previously had a look on their web site but they don't have the 1" shaft model that is suitable for the 4333A, they just have the 3/8" :thnkfast:

I sent them an email asking for the 1" and they can't get it :(

Spirou,

the 4333 should use a spacer at the L-Pad shaft! So you probably don't need a 1" L-Pad. Check this.

[spirou38]

Spirou,

the 4333 should use a spacer at the L-Pad shaft! So you probably don't need a 1" L-Pad. Check this.

Hello Guido,

Yes there is a 8 to 10 mm spacer. Probably 1/3" ?

1" shaft = 25.4 mm
better usable lenght of 1" shaft = 25.4 - 10 (spacer) = 15.4 mm
3/8" shaft = 9.5 mm

So, when removing it, it will be short of about 5 or 6 millimeters :(

[macaroonie]

I think this will clear matters up

[Guido]

It's crystal clear that using a shorter shaft with the same spacer won't work.
It's also crystal clear that using no spacer won't work either.

What about using the partsexpress L-Pads and modify the spacer?

Bingo!

[spirou38]

I think this will clear matters up

Hello Macaroonie,

They will be perfect for me :D

Did you received the private mail I sent this morning ?

[spirou38]

It's also crystal clear that using no spacer won't work either.

Yes because the cables are attached to the plate just under the l-pad.


What about using the partsexpress L-Pads and modify the spacer?

The partsexpress shaft is 3/8" that is not long enough even without spacer :(

[Zilch]

Somebody needs to find or start making shaft extensions or "long" knobs.... :(