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Loud & Clear
02-18-2015, 04:44 PM
It's Been Awhile For Me To Be On This Forum And Posting, Due To A Horrific Brain Injury... But I'm Glad To Be Able To Post My JBL 5234 Crossover Build..

Here Are The Basics: I Bought This Unit Off The Bay. I Received It, And Realized It Was Brand New, Never Plugged In... So Cosmetically It Is Nice. Electrically, Not So Nice. Funny What Just Setting Will Do, Even The Power Cord Was Rotting Away. Anyway, I'll Try To Make This Fairly Short, If You Have Questions Please Ask.

First Off, I Replaced All The Electolytics Except The Coupling Lytic That Was Part Of The H.F. Volume Control (the variable pot has ground potential) So I Used The Usual 25uf Nichicon ES Units, However, I Did Bypass Those Caps With A .01uf Polystyrene Film Cap. So, Lets See, Like I Was Saying I Did Replace (after a little math) The Lytics With Metalized Polypropylene Units. The Power Supply Lytics Are 220uf Panny FM's. I Replaced The 5% Carbon Film Resistors With 1% Metal Film, And In The Signal Path, All Resistor Slots Are Filled With 1/4 Watt Takman REY Units. I Removed The Internal Boost Cut Filter Switches, And Just Ran A Jumper To Energize The +6db @ 30hz. The Last Thing I Need Is A Bunch Of Switches To Oxidize On Me, And Become Resistors. I Chose This Particular X-Over, For It's Simplicity... I Do Not Need A Thousand Pots On The Front To Oxidize On Me... Where Was I, Oh Yes I Was Just About To Remove The Relay In This Unit, Then I Realized It Was Hermetically Sealed. I Installed New Gold Plated RCA Jacks On This Unit As Well... I Am Thinking About Removing A Bunch More Wiring That Connects To The Rear Panel Screw Terminals, I Really Do Not Need A Bunch Of Wiring, That Is Not Needed... Also Note: I Chose To Hang Onto The Original OP Amps, As I Figured There Performance Is Still Pretty Decent. Correct Me If I Am Wrong. I Just Did Not Want To Add A Bunch Of Filter Circuitry On The V+ And V- Pins On These Higher Performance Chips. I'll Stop Jabbering Now, And Let You Look At The Pictures...

NOTE: I Will Be Using My JBL 4350's That I Purchased From Rick (SAE Man)... This Guy Is "The Best"!!! I Have The Most Beautiful Pair Of Speakers I Have Ever Seen!!! My Hat Is Off To You Rick...

Loud & Clear
02-18-2015, 04:46 PM
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Loud & Clear
02-18-2015, 04:58 PM
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Loud & Clear
02-18-2015, 05:00 PM
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Loud & Clear
02-18-2015, 05:02 PM
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Loud & Clear
02-18-2015, 05:04 PM
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martin2395
02-19-2015, 05:18 AM
Nice work!

I have to admit that the 5234 looks more easy to work on than a 5235.

Mr. Widget
02-19-2015, 08:37 AM
Very impressive... and glad to see you back!


Widget

Loud & Clear
02-19-2015, 01:15 PM
Thank You Mr. Widget...

And "Yes" martin2395... The 5235 Contains Radial Capacitors, And 5234 Axial Units... The Axials Leave A Lot More Space For The Larger Film Replacements...

Loud & Clear
02-24-2015, 02:33 PM
Guess I Made This Post To Soon... I've Decided I Need To Clean Up The Wiring, Install 10K Gold Plated Stepped Attenuators For The H.F. Volume Controls, And I Am Toying With This Idea, Remove My Green Nichicon ES Units, And Replace With 22uf WIMA's... Chime In, Tell Me What You Think... :)

BMWCCA
02-24-2015, 06:24 PM
Guess I Made This Post To Soon... I've Decided I Need To Clean Up The Wiring, Install 10K Gold Plated Stepped Attenuators For The H.F. Volume Controls, And I Am Toying With This Idea, Remove My Green Nichicon ES Units, And Replace With 22uf WIMA's... Chime In, Tell Me What You Think... :)
Very impressive work. :applaud:

But I'm puzzled how you manage to write your entire posts in Title Case? Are you writing in Word and cutting and pasting? Otherwise It Seems Like It Would Be An Awful Lot of Trouble to Type That Way! ;)

Loud & Clear
03-09-2015, 01:57 PM
Thank You...

No Just Typing A Mile A Minute, My Left Little Finger Finding That Shift Key Very Efficiently... LOL... :) Oh, I can type like this as well, but somehow I have managed to move just as fast either way... :)

mciavaglia
01-17-2016, 07:48 PM
Hi Guys,

I am reasonably new here and this is my first post!

I have been researching the 5234 crossover and stumbled across this thread, there is some great information here and I love to see what you are doing with this fantastic vintage gear.

I have recently bought a 5234 crossover and realise that replacing the old electrolytics is probably a good idea. My question is this: are the capacitors you have used in the upgrade non-polarised? I was intending to use audio grade non-polarised polypropylene caps in place of the old polarised electrolytics as they are much easier to buy and I already have some left over from other projects.

Your answer to this question would be much appreciated!

Again, I love reading what members here are doing, cheers!!

Mark.