N333/L-300 crossover

[300_Summit]

Hello all, as some of you know I've recently become the recipient of my father's L-300's which I had reconed and new L-pads installed. They sound really good. I'm now contemplating recapping the xover. My questions are:

1. Would the 300's significantly benefit from a recap?

2. From the schematic, I know that there are (2) 20uF, (1) 1uF, (2) 1.5 uF, and (1) 16.5uF on each network. Which capacitors are on the top of the xover and which ones are on the bottom submerged in the wax?

3. Can the top caps be replaced without replacing the bottom ones?

4. Should I decide to do a recap, what brand and type of cap should I use?

5. Does anyone have a picture of the bottom of the n333 xover?

Thanks in advance for your help

[Wagner]

Best suggestion I can give you?

Use the "search" feature

There are dozens and dozens of pages here on the subject of your inquiry

You also do not need or have to start a new thread for every new angle/question that pops into your head:
http://www.audioheritage.org/vbulletin/showthread.php?37813-My-L-300-s

Thomas

[Wagner]

3. Can the top caps be replaced without replacing the bottom ones?

4. Should I decide to do a recap, what brand and type of cap should I use?

5. Does anyone have a picture of the bottom of the n333 xover?

Thanks in advance for your help

http://www.ebay.com/itm/Jbl-N-333-Crossover-Network-Pair-L300-4333A-136A-136H-077-LE85-/251823855717?nma=true&si=uGhr4NFdxSJyR9oB82AQ3ZFqfOU%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

[300_Summit]

Best suggestion I can give you?

Use the "search" feature

There are dozens and dozens of pages here on the subject of your inquiry

You also do not need or have to start a new thread for every new angle/question that pops into your head:
http://www.audioheritage.org/vbulletin/showthread.php?37813-My-L-300-s

Thomas

Thanks Thomas, actually since posting the thread, I have found a lot of info on this site about the matter. Particularly an old thread from Regis and what he did with his L-300's xover. I think if do decide to recap, I'll use Dayton caps and go from there. I was looking at using Solen caps, but from what I've read, Solen caps tend to be on the "bright" side.

[Wagner]

Thanks Thomas, actually since posting the thread, I have found a lot of info on this site about the matter. Particularly an old thread from Regis and what he did with his L-300's xover. I think if do decide to recap, I'll use Dayton caps and go from there. I was looking at using Solen caps, but from what I've read, Solen caps tend to be on the "bright" side.
IF you do decide to use the Dayton caps, do not waste the additional money on their "1%" line
The tolerances on the last 25 or so caps I've used from them, of various values, was just as good if not better with the 5%

In other words, with the 5%ers, they measure the same as what's written on them and are very consistent from batch to batch

Use film and foil .01uF by-passes with your rebuild (plenty on that subject here too)
This is a forum favorite:
http://www.parts-express.com/audiocap-ppt-theta-001uf-600v-film-foil-capacitor--027-700

This is what I just recently used/tried for the first time on 3 projects (within the past 6 months). I had been using the Audiocaps as they were so highly recommended. So far, I cannot tell a great deal of difference between the two except the price. I will have to say that I am basing this on subjective listening impressions and not measurements:
http://www.parts-express.com/dayton-audio-dffc-001-001uf-400v-by-pass-capacitor--027-450

[300_Summit]

IF you do decide to use the Dayton caps, do not waste the additional money on their "1%" line
The tolerances on the last 25 or so caps I've used from them, of various values, was just as good if not better with the 5%

In other words, with the 5%ers, they measure the same as what's written on them and are very consistent from batch to batch

Use film and foil .01uF by-passes with your rebuild (plenty on that subject here too)
This is a forum favorite:
http://www.parts-express.com/audiocap-ppt-theta-001uf-600v-film-foil-capacitor--027-700

This is what I just recently used/tried for the first time on 3 projects (within the past 6 months). I had been using the Audiocaps as they were so highly recommended. So far, I cannot tell a great deal of difference between the two except the price. I will have to say that I am basing this on subjective listening impressions and not measurements:
http://www.parts-express.com/dayton-audio-dffc-001-001uf-400v-by-pass-capacitor--027-450


Ok......thanks Thomas for all your help and insight

[300_Summit]

After doing EXTENSIVE research on this forum, instead of recapping my stock crossover, I'm going to build (from scratch) charge coupled networks. I figure, if I'm going to go through all of the trouble of recapping, I may as well just build new networks and leave the original N333s completely unmolested. The only question that I have is whether to build a charge coupled version of the original design or do a charge coupled Nelson Pass version. Any opinions out there?? :D


Thanks,

Lamont

[Wagner]

After doing EXTENSIVE research on this forum......................The only question that I have is whether to build a charge coupled version of the original design or do a charge coupled Nelson Pass version.................................Any opinions out there?? :D
Thanks,
Lamont
Yeah, do some more research (as it would appear that EXTENSIVE means different things to different people)

What you seek is already here x10

[300_Summit]

Yeah, do some more research (as it would appear that EXTENSIVE means different things to different people)

What you seek is already here x10


I've read damn near everything on charge coupled crossovers for the L300/4333. I have the schematics that 4313B posted. I, however, haven't found anything in the LH forum on someone actually building a Nelson Pass CC crossover. If it is, can you direct me to the thread? I was just curious to know whether there would a big difference between a CC Nelson Pass network vs a CC (Original design) N333 network

What I mean by EXTENSIVE, is at least 6 hrs a day, 4 days a week, over the last week or so......almost borderline obsessive, lol

[Wagner]

I figure, if I'm going to go through all of the trouble of recapping, I may as well just build new networks and leave the original N333s completely unmolested.
I have never understood that one..........many members here subscribe to it though

"Preserving" old networks? The ones with the generic Mylar caps and Jap L-pads all mounted on slabs of Masonite hardboard? They were nothing more than decent quality parts assembled as cheaply as possible yet well enough to still be rugged enough to prove reliable (talking the behind the foilcal point to point designs) Little better with the Greg Timbers era copper trace stuff like the L96

The metal box types, the ones from the Golden Years, I can understand leaving those untouched, up to a point..........but I mean, how difficult is it to unsolder the original devices and put them in a labelled bag if one is that fastidious about it

It's not as if James Lansing assembled the things (and in THAT case I would make exception)

And then there's the ongoing matter of not being able to source today some of the parts that they used yesterday, like exact match inductors for networks such as the original N1200............so, why not re-cap original networks?

If done with care it is 100% reversible and 30-40-50 years old solder joints should be re-flowed anyway
You can keep most of them absolutely original in their appearance, even better with the ones JBL used glue, basically poured all over the place, to secure the caps

I do care that my restoration efforts both electrical and cosmetic say true to the original designs but I'm not going to obsess over it (or squirrel away boxes of old passive devices) Again, for what!?

(Hi! My name is Thomas and I'm a cardboard, sand and wax tube re-stuffer)

Potted networks? Now that's another discussion

This practice of "NEVER" touching original networks, that they should be"put away" is absurd (again, unless it is a piece of HISTORICAL significance) What for? What purpose does it serve?

Photograph the original as received, make sure you have a schematic that coincides with your examples and have at it is my philosophy (I always save all original parts for future reference/research, but even that's a bit much) Made in Mexico no name caps, 25-33% of which have drifted as much as 30-40% off value on at least one in every pair of networks I have overhauled...................again, remind me of why I need to save this junk? I'm going to start saving burned out light bulbs too?

Having old speaker crossovers to use as paperweights and conversation pieces is not going to be of much interest to but a very few in another 10 years.............and that will be for those who need the correct original parts from which to build or repair their networks in their ancient systems, that, or the information, values and data discussed above in order to pull off a clone (and even this is a stretch)

I myself would rather have the very cool and beautiful industrial metal boxes as JBL made them, stuffed with new spec spot on components and working the way they were meant to be, rather than sitting on a shelf somewhere or in a box, surely to be sold for next to nothing, hauled off to a thrift, or more likely than not thrown out 2 seconds after I am dead

Not going to be a great deal of interest in this guys after we are gone, some, but nothing like what's left of us now

I say USE the stuff

[300_Summit]

I have never understood that one..........many members here subscribe to it though

"Preserving" old networks? The ones with the generic Mylar caps and Jap L-pads all mounted on slabs Masonite hardboard?

The metal box types, the ones from the Golden Years, I can understand leaving those untouched, up to a point..........but I mean, how difficult is it to unsolder the original devices and put them in a labelled bag if one is that fastidious about it

It's not as if James Lansing assembled the things (and in THAT case I would make exception)

And then there's the ongoing matter of not being able to source today some of the parts that they used yesterday, like exact match inductors for networks such as the original N1200............so, why not re-cap original networks?

If done with care it is 100% reversible and 30-40-50 years old solder joints should be re-flowed anyway
You can keep most of them absolutely original in their appearance, even better with the ones JBL used glue basically poured all over the place to secure the caps
(Hi! My name is Thomas and I'm a cardboard, sand and wax tube re-stuffer)

Potted networks? Now that's another discussion

This practice of "NEVER" touching original networks, they should be"put away" is absurd (again, unless it is a piece of HISTORICAL significance) What for? What purpose does it serve?

Photograph the original as received, make sure you have a schematic that coincides with your examples and have it is my philosophy (AND always save all original parts)

Having old speaker crossovers to use as paperweights and conversation pieces is not going to be of much interest to but a very few in another 10 years.............and that will be for those who need the correct original parts from which to build or repair their networks their ancient systems

I myself would rather have the very cool and beautiful industrial metal boxes as JBL made them, stuffed with new spec spot on components and working the way it was meant to be, rather than sitting on a shelf somewhere or in a box, surely to be thrown out or hauled off to a thrift 2 seconds after I am dead


Point taken......the reason that I want to preserve my networks and build new ones is so I can compare the new with the old and see if I'm able to hear a tangible difference.

[Wagner]

Point taken......the reason that I want to preserve my networks and build new ones is so I can compare the new with the old and see if I'm able to hear a tangible difference.
I digressed with that post

If you don't restore/refresh the originals first and listen to those FIRST in order to have as meaningful a baseline/reference as possible to the system as originally built, then what have you accomplished?

I don't know if it was here or another thread? But the point being obvious

Of course you'll hear a difference, but how will you know how to ascribe what to what, and what the degree or magnitude of that difference really is in the new network or the fact that your original design reference will be 40 years old and possibly operating with significantly degraded parts?

Follow me?

I always encourage folks to start with stock before jumping on the mod or upgrade wagon, with ANYTHING, speakers or electronics. I learned this the hard way.

In this case, the charge coupling is a proven winner, however, you will still not know as best one can, what the system sounded like as originally designed (and that fact is what got me off on the "why not" tangent above) or an accurate assessment of the degree of improvement resulting from your new network.

Good luck whatever you do,
Thomas Wagner

[mech986]

Thomas, I'm sure you're familiar with the N333, but if not, here's a couple of pics:

http://www.hifido.co.jp/photo/03/186/18650/a.jpghttp://i.ebayimg.com/00/s/MTIyNlgxNjAw/z/GA0AAOSwzrxUzYit/$_3.JPG

They are the boxed and potted types. There is considerable work in taking the boxes apart, melting the potting compound, changing out the caps, and then putting it back together to preserve the original cosmetics, especially if one is going to try to put in new film caps to replace the flatter ovals - there is precious little room under the protective grille in the OEM form.

The reason to build new and preserve old as is is because the oem crossover is still very valuable by itself, even moreso with the attached wiring and L-pads, to collectors and restorers who value the original design. (I've seen the N333 go for as much as $700/pr). If I was going the modded crossover route, I'd go with new boards and/or box, and build to my heart's content, especially because it will take up much more room, maybe even two layers thick if you want to conserve space. As for CC version is better, haven't heard or seen anyone do the Pass design but I know some have.

OP, google L300 crossover, images, and you'll see a bunch of DIY versions to give you ideas about it, also, CC L300 will get you some additional. of course, be prepared to spend a bit of money, it will be well worth it.

IMHO, I'd also be looking to refresh or renew your LE85 diaphragm (but reservations about breaking a red wax seal), look into new aluminum OEM JBL ($$$$), OEM Titanium but somehow get them aquaplas coated, or switch to Radian AL with mylar suspension - but again, may require crossover tuning with the last one.

[Wagner]

Thomas, I'm sure you're familiar with the N333, but if not, here's a couple of pics:
They are the boxed and potted types. There is considerable work in taking the boxes apart, melting the potting compound, changing out the caps, and then putting it back together to preserve the original cosmetics, especially if one is going to try to put in new film caps to replace the flatter ovals - there is precious little room under the protective grille in the OEM form.

The reason to build new and preserve old as is is because the oem crossover is still very valuable by itself, even moreso with the attached wiring and L-pads, to collectors and restorers who value the original design. (I've seen the N333 go for as much as $700/pr). If I was going the modded crossover route, I'd go with new boards and/or box, and build to my heart's content, especially because it will take up much more room, maybe even two layers thick if you want to conserve space. As for CC version is better, haven't heard or seen anyone do the Pass design but I know some have.
Yes I am familiar, I wouldn't have posted if I wasn't

I make no argument with any of your points except to say that removing the potting material and refreshing these networks is not all that difficult if you have any mechanical skill and common sense

As for which approach is "better"? Well, I've already shared what I think on that one as well

I am also aware of the money these old networks are realizing, now, but that won't last forever. You think (rhetorical question here) that those paying it are doing so in order to repair a pair of L300s? I doubt it very seriously

And none of it matters if one or more of the caps is off spec value.............don't care what people are paying.

I bet you a nickel that for the most part they are being purchased (for that stupid money) by those building clones because those building want that beautiful original JBL box but more importantly those NLA inductors. If what I suggest was NOT the case then there should be readily available "core" units available...............so, back to my position:
UNLESS you are a cannibal/flipper, and if you plan to use these speakers, restore the original networks to as good if not better than new.....................I mean you can only wind up with a pair of N333s one of two ways: by owning a pair of L300s OR buying them from a cannibal/flipper or some other parts seller

Right?

[300_Summit]

Thomas, I'm sure you're familiar with the N333, but if not, here's a couple of pics:

http://www.hifido.co.jp/photo/03/186/18650/a.jpghttp://i.ebayimg.com/00/s/MTIyNlgxNjAw/z/GA0AAOSwzrxUzYit/$_3.JPG

They are the boxed and potted types. There is considerable work in taking the boxes apart, melting the potting compound, changing out the caps, and then putting it back together to preserve the original cosmetics, especially if one is going to try to put in new film caps to replace the flatter ovals - there is precious little room under the protective grille in the OEM form.

The reason to build new and preserve old as is is because the oem crossover is still very valuable by itself, even moreso with the attached wiring and L-pads, to collectors and restorers who value the original design. (I've seen the N333 go for as much as $700/pr). If I was going the modded crossover route, I'd go with new boards and/or box, and build to my heart's content, especially because it will take up much more room, maybe even two layers thick if you want to conserve space. As for CC version is better, haven't heard or seen anyone do the Pass design but I know some have.

OP, google L300 crossover, images, and you'll see a bunch of DIY versions to give you ideas about it, also, CC L300 will get you some additional. of course, be prepared to spend a bit of money, it will be well worth it.

IMHO, I'd also be looking to refresh or renew your LE85 diaphragm (but reservations about breaking a red wax seal), look into new aluminum OEM JBL ($$$$), OEM Titanium but somehow get them aquaplas coated, or switch to Radian AL with mylar suspension - but again, may require crossover tuning with the last one.


Yeah Mech, I've seen tons of DIY crossovers. A lot of real nice custom stuff out there. As far as removing the LE-85 diaphragm, I'm of the opinion that I won't replace that until it blows up, lol. You can't find those anymore..........But, they were my father's speakers,they weren't abused and didn't get played a lot. Until I had them "cleaned up" they had been in the basement for the last 30+ years.....I'm pretty confident that those diaphrams are ok, and will be for a while

[Wagner]

Thomas, I'm sure you're familiar with the N333, but if not, here's a couple of pics:
(I've seen the N333 go for as much as $700/pr)

Again, yeah
See post #3 and click on the ePay link
$692.00 + Shipping (close enough?)
EIGHTEEN bids
And with DAYTON caps..............so I guess it ain't the vintage craps they want, huh?