Altec 32343 Network Divider

Hello Altec Users!

First post here. I came across your forum while searching for info on the Altec 32343 speaker cross-over.

Some time ago, I purchase from a friend a set of home-built PA speakers. Loaded with a 12 inch JBL woofer and plastic rectangular horn. I never used them until recently when I hooked them up to a small stereo system in my workshop. They are a compact speaker, dimensionally resembling something like the 9849, but with a full 1 inch vent gap across the bottom of the entire baffle board. They use the 32343 Network Divider with the HF compensation and 1/4" phone plug input.

They sounded just "ok." Nothing great. One of them sounded a bit different than the other, and the compensation resistors seemed like they were both dirty, needing some cleaning. So I pulled out the 32343 boxes and noticed that one of the caps in one unit was leaking and the same cap in the other unit was completely blown! There was paper everywhere. And I could see that someone had done some messing around in there... bad soldering. I figured that I would just buy some quality caps and go through both units. But then it occurred to me that maybe whoever was in there may have changed something, and I was hoping to get a good schematic to verify that things are right and to get the cap values. Does anybody here have that schematic? Also, thought I would ask if you guys have a preferred type/brand of cap to use in these?

I will post some pics of one of the units tomorrow night.

Thanks in advance,

Allen

i prefer oil caps.

i have no schematic .









37

Ok... here are some pics... sorry, a bit blurry...

It turns out the woofers are JBL 123A-1 (8 ohm)

http://www.hostboard.com/forums/hbmc...2011/04/45.jpg


I don't know about the horn. I found no markings on it. The black rear cover is cast aluminum and the horn is plastic.


http://www.hostboard.com/forums/hbmc...2011/04/46.jpg


I don't know if the cabinet is home-made or if it is an Altec Lansing design. (Ed: Now I think it is DIY). It is made from 3/4 inch birch ply and its outside dimensions are: 24" (H) x 16.5" (W) x 12" (D). It doesn't have a lot of physical depth, as though it was designed around JBL 123A-1 which has a shallow basket.


http://www.hostboard.com/forums/hbmc...2011/04/47.jpg


In both of the 32343 cross-overs, the black plastic caps were leaking, and in one of the cross-overs, one of the 18uf caps fully exploded. I'm sure this happened before I bought these and it's probably why I got them so cheap. Cap values are: 3uf/75V; 6uf/100V; 8uf/75V; 18uf/50V.


http://www.hostboard.com/forums/hbmc...2011/04/48.jpg


So I was looking at replacing the old caps with Solens, since there is not a lot of room inside the control box and they are not too expensive. I've never used them though so I don't know what to expect. The old caps (marked "TSI") do appear to be a PIO cap, judging by all the paper shrapnel plastered over everything. If you guys have any suggestions on better caps, please feel free to chime in.

Thanks again,

Allen

P.S. still would like the schematic if anybody has it. thnx.

Hi Allen,

http://www.hostboard.com/forums/hbmc...2011/04/53.jpg

- If you click on the above image you'll see the complete collection of ( Lansing Heritages ) 1975 Altec reference charts .

- The last page of those charts, has 3 references to the network model which you have .

- That network # ( 32343 ) was installed in the 9849 ( series ) of speakers.

- The stock 9849-8B has different dimensions from what you've posted / maybe yours was the original design or maybe it's a custom build .

- FYI, 9849s are supposed to have 414 woofers in them / not a JBL and certainly not the JBL 123A-1 model .

- I've scoured the forums and can't find a schematic of this crossover for you / apparently no one has yet committed it to paper .

- Bowtie427 has a pair of these and has made numerous mention of the network having some built-in HF compensation (IE; midrange suppression ) .

- From the capacitor parts ( quantity & the values which you've mentioned ), it appears that the network could have a Zobel in the LF area of the network ( most likely the 18uF cap, if it's wired in series with an @ 7.5R resistor / then strapped across the networks' woofer output ). The 3uF & 6uF caps should belong within the HF portion of the network with either the 6uF cap ( or the 3uF ) spanning ( ie; bypassing ) the typical Altec "T-Pad" & therefore engaging the mentioned HF compensation .

<> EarlK

ps ; What resistor values to you see ?

Hi Earl K-

Thanks for the link and for looking around for the schematic. I looked before I posted. I must commend you guys for having such a nice library of documents!! Very handy!

The resistors I saw all looked like 10w ceramics... going from memory here... 2 x 5ohm in series and an 8ohm. I will verify how they are wired.

I'm just wondering if it might be worth changing out the ceramic resistors for non-inductive 25w (finned aluminum) resistors that I can bolt to the box for extra cooling. These would have the additional benefit of being much smaller than the huge ceramics.

The 18uf cap that exploded was installed right up against one of those ceramic resistors. I can't imagine the heat would have done it any good. I have no idea how long it was like that. I have not used these speakers much since I have had them.

I was hoping to have a look at a schematic of the network to verify if it has been altered. Just wanted to know. If I get a free hour, I will attempt to derive it for the group.

Best,

Allen

Allen--I saw your photos regarding this thread over at L.H. and am posting the link here since you mentioned you'd be posting the photos here eventually. This may help you to get some more info from our members.
http://www.audioheritage.org/vbullet...What-are-these Your H.F. drivers look very similar to Altec 802-8G drivers and the cabinets look to be home-made, but there are most likely other members here who can be more specific/add to these observations.

By the way, I have used the Solen caps (that you mentioned) in my Model 19's and Model 14's and have found them to have excellent sonic characteristics. However, everyone has their own preferences in caps and I have seen threads regarding capacitor preferences generate almost as "spirited" of a debate as threads regarding wire/cables. Best of luck with your project....

Hi V.O.T.-

Thanks for the cross-link over to L.H., and for the info on the Solens. I went ahead and purchased a set for both networks and I'm sure they will be more than adequate. They would have to be better than the old dried up caps that were in there!!

I tend to prefer paper in oil caps or good quality foil in oil, but with the space limitations on this network box, and the cost of oil caps... HA! The caps would be worth more than the rest of the components combined!

With regard to the HF drivers, I too thought they looked a lot like something that might have come in an old Altec. They actually sound very good whatever they are. Great dispersion pattern and wide "sweet spot." The 123A-1's seem to lack punch. I have no experience with them beyond this project, so I don't know their innate character. Do people ever modify these? Or is that considered sacrosanct amongst the vintage JBL fans? Just curious. I'll re-evaluate them after the XO networks are finished.

Well I hope to have some time to draw up the 32343 schematic. When I do I will post at both forums.

Thanks again for the assistance,

Allen

I'm glad I could help.

Quote:

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Originally Posted by Corona Blue

The 123A-1's seem to lack punch. I have no experience with them beyond this project, so I don't know their innate character. Do people ever modify these? Or is that considered sacrosanct amongst the vintage JBL fans?

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If they were my speakers I'd replace those 123A-1's with a pair of 414's. As you probably know, Altec doesn't manufacture the 414's any more (or any of their high quality speakers) as a result of being bought out by Sparkomatic (to make a long story short). However, Great Plains Audio does manufacture brand new 414's. If you've never heard of GPA, they are owned and operated by former Altec employees who bought the designs, schematics, tooling etc. to make authentic Altec Lansing replacement parts. Here's a link to some brand new 414's http://cgi.ebay.com/Altec-Lansing-GP...item35ad4c1876

This link is for Great Plains Audio's website for more info about the company http://www.greatplainsaudio.com/ If you call them, you can bypass Ebay. Of course you could look for a used pair of 414's, but I'd go for the brand new ones--you will be amazed by their sound and you don't have to worry about buying used (and potentially expensive) speakers that may need re-cones, etc.

I clicked on the links that Earl K was kind enough to provide for you http://altecpro.com/pdfs/vintage/Spe...r%20System.pdf I can see that your crossover was designed to work well with the 414 woofers and Altec 902 h.f. driver which means AFAIK it should also work well with your h.f. driver (other members please chime in to confirm this). Altec used the 802-8G (which is what your drivers look like to me?) in Model 19's for example, and then later switched to the 902 h.f. driver but kept the same crossover--in other words they were used more or less interchangeably by Altec in some applications AFAIK (the 902's replaced the 802-8G's). So, you'd basically have speaker very similar to an Altec 9849-8B studio monitor which was an excellent speaker! You would of course, have to adjust the tuning of your cabinets to optimize them for use with the 414 woofers--there are people here in addition to myself who can coach you on that (a few in particular who are very knowledgeable in cabinet tuning). It's not as hard as you might think.

Keep in mind, you can sell the JBL woofers (ebay, audiogon, craigslist, etc.) to recoup a good portion of the cost of new woofers--so for not much money--you could have some amazing speakers--very similar to Altec 9849-8b studio monitors in home made cabs. Hopefully others here (there are some amazing experts here) will chime in to either support or modify my recommendation......

I'll pull out an unmolested 32343 this evening and try to get some comprehensive pics that a wiring diagram can be drawn from.

If those HF drivers have been paired with the 32343's all along, they're likely a late version of 806 equipped with 23744 diaphragms and in some cases tangerines.

AFIAK, you would only find 902's in very late 9849's that also used ferrite 414-8E's by this time the networks were no longer labeled 32343, they were instead labeled with "9849-XX loudspeaker system", i don't think there are many examples of Altec mixing alnico and ferrite motors in the same systems.

Quote:

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Originally Posted by bowtie427ss

If those HF drivers have been paired with the 32343's all along, they're likely a late version of 806 equipped with 23744 diaphragms and in some cases tangerines.

AFIAK, you would only find 902's in very late 9849's that also used ferrite 414-8E's by this time the networks were no longer labeled 32343, they were instead labeled with "9849-XX loudspeaker system", i don't think there are many examples of Altec mixing alnico and ferrite motors in the same systems.

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They look similar to the Altec 802-8G (great h.f. drivers with 23744 diaphragms and tangerine phase plugs)--but Bowtie is more of an authority here. If he says they're likely late versions of Altec 806's with 23744 diaphragm and possibly tangerine phase plugs, those are also amazing h.f. drivers and I'll defer to his expertise there. I'd still recommend going with Great Plains Audio's brand new (alnico) 414's. The 414 woofers were selected by the Altec engineers to work well with your crossover (and with the 806's)--and they are incredible woofers..... You could also, as I mentioned, go with used 414's but if they need work done on them, you won't be saving money going that route. I checked ebay and I don't see any 8 ohm alnico 414's on there currently. I did see some 16 ohm 414's (a resistor can make 16 ohm woofers work with an 8 ohm speaker system)--in the description for one pair the seller states he was going to send them to Great Plains Audio for service--so you've got a seller who seems to know what he's doing--but with his asking price combined with the cost of servicing them I'd go brand new..... With new 414's installed, and possibly a tuning adjustment to the cabs, you won't be complaining about a lack of "punch" any more!

Oh i'm no expert here VOTT, but i am familiar with the 9849's as i've owned a few. AFAIK, the 9849 is the only speaker that was factory equipped with the 32343 XO, and the 23746 compression driver. Apparently the 23746 was made with both annular metal and radial plastic(tangerine) phase plugs, i think member RonSSS has examples of each. I currently have 9849-8D's with annular metal phased 23746's, those drivers "look" like an 802-8G with the same new style rear cover and rough cast exterior surface except they're the shorter body and smaller magnet of the 806. Here's a pic of one of my drivers from a while back.

http://www.hostboard.com/forums/

Quote:

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Originally Posted by bowtie427ss

Oh i'm no expert here VOTT, but i am familiar with the 9849's as i've owned a few. AFAIK, the 9849 is the only speaker that was factory equipped with the 32343 XO, and the 23746 compression driver. Apparently the 23746 was made with both annular metal and radial plastic(tangerine) phase plugs, i think member RonSSS has examples of each. I currently have 9849-8D's with annular metal phased 23746's, those drivers "look" like an 802-8G with the same new style rear cover and rough cast exterior surface except they're the shorter body and smaller magnet of the 806. Here's a pic of one of my drivers from a while back.

http://www.hostboard.com/forums/

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Allen, does that look like your h.f. driver? (click to enlarge the photo) It looks similar to me but hard to tell from the angle and lighting of your (Allen's) photo. If that's your driver, I'd still recommend 414's since they were selected by Altec engineers to work with that h.f. driver and your crossovers.... As I mentioned before, your speakers would be very similar to Altec 9849's (which are great speakers) in (well made) home made cabs. With those woofers you'd have an amazing pair of speakers.....

Quote:

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Originally Posted by Corona Blue

The cabinet is well made from 3/4 inch birch ply and its outside dimensions are: 24" (H) x 16.5" (W) x 12" (D) with a 3/4" vent across the lower part of baffle board.

Allen

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Wow! Thanks so much for your kind help guys!! I spent this afternoon deriving the schematic. Have a look and see if it looks right to you.

http://www.hostboard.com/forums/hbmc.../2011/04/1.png

I haven't had time to put a meter on VR1 to verify its value. I suspect it is around 100k. (04/25 UPDATE: VR1 is 7 ohm/50 or 100 watt component) And I don't know the values of the inductors. If anybody knows this stuff, I can update it. Once we know it's right, feel free to add it to the documents lib.

VOTT- yes, that does indeed look like the same HF driver! Sorry about those blurry snaps... batteries in the cam were dying so auto focus was dodgy... I will attempt to get some clearer shots tomorrow... for now... just put yer glasses on! :-)

Let me know and thanks again.

Allen

:thankU:

Thanks so very much for this Allen !

I'm always very thankfull when someone takes the time to expose the workings of an older network such as this . We all benefit by these efforts / so thanks again !

Does it look right ?

- Yes, electrically your layout is very workable ( when designing for an @ 1500 to 1600hz acoustic crossover point ) .
- The component layout ( visually ) on your drawing is fairly unconventional ( & may confuse untrained eyes ) / but it's the eletrical layout that matters here .

FYI ;

• L1 & L2 could be in the neighbourhood of 1.2 mH for a standard "B2 filter" rolloff ( B2 = 2nd order ButterWorth filter ) .
• L3 ( at that location ) would need to be @ .075 to .20 mH to function properly and do anything of importance to the HF filtering .
• VR1 should be a standard type 8 ohm variable Lpad ( 100 watt ) .
• The values of the capacitors do "ball-park" to where I would expect them ( ie; knowing the components somewhat , as well as Altecs' standard approach to dealing with the FR curves of those components ) .

- It would be nice to have your layout confirmed by a second set of eyes on another network ( before declaring this all correct ) .

<> cheers EarlK

Thanks EarlK-

If anybody would like to modify the schematic, I can email them the source file which was done in TinyCad (shareware/freeware). It would be great to have it laid out so it would be clear to anyone. My thought in the lay-out was to clearly show the two sides of the network, but better is better!

Just PM me or send an email!

Best,

Allen

Here are some clearer pics of the horn and driver... don't know if this will help you identify it or not. Let me know if you need me to do anything to identify these. I'm not all that familiar with what I am looking for on this.

http://www.hostboard.com/forums/hbmc...2011/04/54.jpg


http://www.hostboard.com/forums/hbmc...2011/04/55.jpg


http://www.hostboard.com/forums/hbmc...2011/04/56.jpg


http://www.hostboard.com/forums/hbmc...2011/04/57.jpg


The driver is painted with black wrinkle finish paint. The horn feels like heavy carbon plastic and it mates to the driver with a fiberboard gasket that is about 1.5mm thick.


Let me know what you think and if there's something else I should look at...

Thanks again,

Allen

Looks like the 806 style driver. Hard to say exactly what it is until you take it apart and remove the fram. Or look down the throat and see what kind of phase plug is in there. Tangerine would be orange.

Looks like the drivers were subjected to moisture.

I don't think the horns are Altec.

Ron

The caps you have there are original. All altec crossovers from that era used those black caps with red ends. So I don't think anyone had changed values. I'm betting the blowed up one is the shunt cap that goes across the woofer. Which means someone really cranked the volume!

I don't think you would gain anything by replacing the resistors. They certainly shouldn't be getting hot.

Is that JBL woofer some sort of high powered deal? If someone had these up loud enough to pop that cap, I wonder how the hf fram survived?

I have a pair of the 9849's and I hate to adnit that I've never listened to them......

Ron

Quote:

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Originally Posted by Corona Blue

Hi Earl K-

Thanks for the link and for looking around for the schematic. I looked before I posted. I must commend you guys for having such a nice library of documents!! Very handy!

The resistors I saw all looked like 10w ceramics... going from memory here... 2 x 5ohm in series and an 8ohm. I will verify how they are wired.

I'm just wondering if it might be worth changing out the ceramic resistors for non-inductive 25w (finned aluminum) resistors that I can bolt to the box for extra cooling. These would have the additional benefit of being much smaller than the huge ceramics.

The 18uf cap that exploded was installed right up against one of those ceramic resistors. I can't imagine the heat would have done it any good. I have no idea how long it was like that. I have not used these speakers much since I have had them.

I was hoping to have a look at a schematic of the network to verify if it has been altered. Just wanted to know. If I get a free hour, I will attempt to derive it for the group.

Best,

Allen

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I had a minute to revise the schematic of the Divider Network... just some clean up really. I wanted to show the logical correlation between the Zobel filter in the LF and the LR filter in the HF sections. And I added in the extrapolated inductor values as provided by Earl K. If you have additions or corrections, please advise, and I will do so.

http://www.hostboard.com/forums/hbmc.../2011/04/2.png



I will re-post on Wednesday with some measurements of the horn driver. One question: If I choose to remove the rear cap, do I need to be careful about anything in particular? What to I need to be wary of?

Thanks!

Allen

Quote:

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Originally Posted by Corona Blue

... If I choose to remove the rear cap, do I need to be careful about anything in particular? What to I need to be wary of?

Thanks!

Allen

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The magnet can suck your screwdriver tip right into the diaphragm if you're not prepared for the pull.

Driver measurements:

From the rear surface of the driver ring to the forward surface of the driver's housing, I measure 2.210"


http://www.hostboard.com/forums/hbmc...2011/04/60.jpg


The horn base gasket is .100" thick, so 2.310" to the horn flange face.


Don't know if this helps identify the unit or not. Maybe it's just a Korean clone driver???? Hey, no biggie if so... the horns sounded pretty darn good!!


Anybody know if these measurements narrow it down to a known driver?



Allen

Quote:

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Originally Posted by Corona Blue

Driver measurements:

From the rear surface of the driver ring to the forward surface of the driver's housing, I measure 2.210"

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Too small to be 802-8G's--I suspect they're 23746 compression drivers as shown on the chart that Earl K provided (under Altec 9849-8D) http://www.lansingheritage.org/image...ers/page11.jpg That would also make sense as to why they are paired with Altec 32343 crossovers in your cabs (not to imply that these things always make sense!).....

Quote:

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Originally Posted by Corona Blue

Don't know if this helps identify the unit or not. Maybe it's just a Korean clone driver???? Hey, no biggie if so... the horns sounded pretty darn good!!


Anybody know if these measurements narrow it down to a known driver?



Allen

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No, those aren't Korean clones--they look to be real Altecs--we just have to find out which ones. Bowtie and RonSSS-- you guys both own 9849's. Any chance one of you gentlemen can measure your h.f. driver to help figure this out (or does anyone know the dimensions of a 23746 driver)?

Quote:

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Originally Posted by RonSSS

The caps you have there are original. All altec crossovers from that era used those black caps with red ends. So I don't think anyone had changed values. I'm betting the blowed up one is the shunt cap that goes across the woofer. Which means someone really cranked the volume!

Ron

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I agree--every Altec crossover I've ever recapped from that era had those original caps in them--here are the ones I replaced that were in my Model 19's

http://www.hostboard.com/forums/hbmc...2011/01/43.jpg

Quote:

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Originally Posted by RonSSS

I have a pair of the 9849's and I hate to adnit that I've never listened to them......

Ron

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Ron, you should dig those things out and crank them up! Don't you know there are underprivileged children in poor countries who may never get to experience tinnitus?

The 2.21" says 806 type driver. I can't find my calipers, but a tape measure confirmed that.
So next question is the phase plug. Just use a flashlight in the throat....remove it from the horn....and tell us if it's silver or orange.

Then be sure to measure the resistance to make sure it's not dead.

Alwaws fun to remove the frams and get the part number....but if you haven't done it, you can damage them pretty easy.

If you want to try, I'll give you my procedure.

These odball 806's of mine have the desired 23744 lightweight frams and the tangerine phase plugs.

And yeah, these have been sitting in my living room half assembled for 6 months now. I just need to remove one bug screen, put them together and haul em down to the audio room.

It's hot rod season. Headed out the the garage to Chop, Cut, Rebuild.......and weld!

Ron

Gentlemen! Thanks a million for your patience and good will toward my newbie ignorance.

Yes, VOTT, those caps are exactly what I have... even down to the leaking crystallized cap goo... mmmm... caaaaaap goooo...:doh:

I'm convinced that these XO's are as per their original spec. The new Solen's arrived today, so I'm hoping I will get a couple of free hours tomorrow to install them and try them out. Stay tuned for a full report.

OK... RonSSS, thanks. So, is the screen I'm seeing in the throat of the driver actually part of the diaphram ass'y? Does anybody have an exploded diagram of one of these that I can study?? Just so I know what I'm working with.

Thanks everyone for the help and the enthusiasm.

Allen

Hi Allen,

The screen assembly is in front of the fram. Controversial about removing it, I like the change.

You will be able to see through it.

Ron

Quote:

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Originally Posted by RonSSS

The 2.21" says 806 type driver. I can't find my calipers, but a tape measure confirmed that.
So next question is the phase plug. Just use a flashlight in the throat....remove it from the horn....and tell us if it's silver or orange.

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Nice! Thanks for measuring Ron--now we're getting somewhere..... Allen, with the horns you have, you won't have to remove the drivers from the horns to see the phase plug. Just shine a flashlight in the throat of the horn and you'll see the phase plug. If it's a tangerine plug it will look like the orange circle at the left of this photo--if you use a bright flashlight--even through the screen you will see what looks like tangerine slices and an orange-ish hue....
http://www.hostboard.com/forums/hbmc...2011/04/62.jpg

Quote:

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Originally Posted by RonSSS

And yeah, these have been sitting in my living room half assembled for 6 months now. I just need to remove one bug screen, put them together and haul em down to the audio room.

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Ron, my Model 14's and 19's still have the bug screens in them. What differences/advantages do you notice from removing them? Since replacing the capacitors in my speakers with Solens, I am extremely happy with their sound. However, if there's a way to get them to sound even better, of course I'm interested. These are being used in my home, and I don't move them around. Do I need the "protection" of bug screens? Anyone else want to chime in about the merits or drawbacks of removing the screens? I play my speakers without the grills on--I don't want the sound to have to pass through fabric. Do I lose anything by having the sound pass through screens?

The bug screen removal was touted by Joe Roberts of Sound Practices Magazine years ago.

So I tried it, it made sense to me.

I used to tweak my system using pink noise. Sitting in the sweet spot, I noticed a real phasey sound when moving my head back and forth even a few inches. Peaks and valleys. With the bug screens gone, that went away, and to my ears, the sweet spot became bigger.

Shine a flashlight through a screen at the wall.

I also noted better HF extension.

This is what I noted. Others here will say that the screens were designed in, and removing them will mess up the sound. I only found improvement. And there aren't many bugs in my basement.

That said, once removed, there is no going back on the older 800 series drivers. You have to cut it out with an exacto knife. The newer 900 series are much easier. The screen is right under the mounting gasket.

If your model 14's have 900 series drivers, you can try it, and change back if you don't like the effect.

Try the pink noise test.

Ron

Hi guys-

Sorry been away for a couple days. Had a few hours to work on the XO's though... here's a before/after of the job...

Before with original caps:


http://www.hostboard.com/forums/hbmc.../2011/05/1.jpg



http://www.hostboard.com/forums/hbmc.../2011/05/2.jpg


And AFTER with new 400V Solens...


http://www.hostboard.com/forums/hbmc.../2011/05/3.jpg


http://www.hostboard.com/forums/hbmc.../2011/05/4.jpg


Pack one of these in your suitcase next time you plan to fly to see the inlaws... Hee hee...

Allen

Quote:

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Originally Posted by RonSSS

Hi Allen,

The screen assembly is in front of the fram. Controversial about removing it, I like the change.

You will be able to see through it.

Ron

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Ron and VOTT:

Well, I tried to look into the throat of the driver, through the screen, and I even removed the horn to have a closer reference. But I swear, using the brightest flashlight I had, I could only make out a silver ring that seemed to have 3 notches that were positioned 120 degrees from each other (around the ring). At the center of this ring, there seemed to be a darker void, but I could not determine if I was seeing an orange hue or not. That bug screen really is a fine mesh and makes it tough. Spent a long time messing with it and finally just put the horn back on and loaded everything back into the cabinets, cleaned all connectors with deoxit and hooked them up.

I was driving these with a NAD 3020A that I have recently gone though completely. Fully re-capped with the best caps I could get my hands on, with some minor bypassing tweeks to the signal chain, but no major mods. Just better components. It's a very sweet sounding little thing, albeit anemic after about the mid throttle point. But I rarely listen to it that loud anyway. I listened to the speakers at about the 1/3 point which is plenty loud and a known sweet spot with this little NAD.

Listening to classical music at first, I had the horn attenuators down to around 6. The HF was very pleasing and apparent. It sounded round and "tubey" at this setting. The main thing I noticed was the LF was smoother and consistent from left to right, which makes sense since one side had a blown 18uf zobel network cap. I experimented for a couple of hours with different settings of the attenuator. I found that I liked them best set at around 1.5 or so: good detail, but not so bright as to be fatiguing. I wish the L-pads were a little more precise. They seem very "notchy." I cleaned them thoroughly with deoxit and compressed air, but not much improvement in their response. I have seen this before with pro-audio PA monitors. It's just not a very precise kind of component.

Overall, a nice improvement. The Solens don't sound much different on the high end than the stock caps at least to my ears. I'm still not crazy about the JBL 123A-1's. I may keep an eye out for some 414's. Were these JBL's designed for a specific application??

Best,

Allen

I was just perusing Altec stuff on ebay, and came across a person selling a single 9849-8b speaker. In the pics, I noted that the terminals are different than on my own...

http://www.hostboard.com/forums/hbmc.../2011/05/5.jpg

Here, you see the spring loaded wire terminals, whereas on mine, it would appear that someone at some time drilled out the center retaining rivet, and installed 1/4" phone jacks in parallel. The guy that I bought these from was a jazz guitarist who used these speakers for a small cabaret style PA system, driving them with a small 100 watt power amp.

Only reason I bring this up is that, in my schematic, I depicted the XO input as having two paralleled TS style phone plugs, never stopping to think that it probably never came that way originally.

Just an interesting footnote.

Allen

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Originally Posted by Corona Blue

Ron and VOTT:

Well, I tried to look into the throat of the driver, through the screen, and I even removed the horn to have a closer reference. But I swear, using the brightest flashlight I had, I could only make out a silver ring that seemed to have 3 notches that were positioned 120 degrees from each other (around the ring). At the center of this ring, there seemed to be a darker void, but I could not determine if I was seeing an orange hue or not. That bug screen really is a fine mesh and makes it tough.

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Sounds like you have the Altec circumferential style phase plug--not the tangerine. There is significant controversy as to which is better. Both have been incorporated into some top notch Altec speaker systems. Some people swear by the tangerine, others consider the tangerine a cheaper product (it is made of molded plastic that's glued into place) and say that any audible improvement is from the h.f. (eq) compensation of the crossover networks/lighter diaphragms used with some of the tangerine phase plug drivers, not from the tangerines themselves..... Does this look like what you saw with the flashlight? (click on image to enlarge)

http://www.hostboard.com/forums/hbmc.../2011/05/6.jpg

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Originally Posted by Corona Blue

Ron and VOTT:

......I wish the L-pads were a little more precise. They seem very "notchy." I cleaned them thoroughly with deoxit and compressed air, but not much improvement in their response. I have seen this before with pro-audio PA monitors. It's just not a very precise kind of component.

Overall, a nice improvement. The Solens don't sound much different on the high end than the stock caps at least to my ears. I'm still not crazy about the JBL 123A-1's. I may keep an eye out for some 414's. Were these JBL's designed for a specific application??

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Parts express has L-pads that would be suitable replacements for the ones in your crossovers. Old, worn, and oxidized L-Pads can degrade your signal. You may find that the combined improvement on the high end from replacing the capacitors with Solens and replacing the L-Pads is much more significant.

As far as the JBL's, a pair of used 414's (in excellent condition) or a new pair of 414's will blow them away IMHO. The 414's are amazing woofers. Not to mention that your crossover network is designed to work with the 414's. As I mentioned before, you can recoup a good chunk of the expense of purchasing 414's by selling the JBL's on ebay or Audiogon, craigslist, etc. JBL's are popular and they will sell if you price them realistically. Here are some recent ebay sales to give you a ballpark idea of what those woofers are worth--depending on their condition of course.

JBL Vintage 123A-1 12" Alnico Woofers Speakers L100 L88 | eBay $135 plus $30 shipping

JBL Vintage 123A-1 12" Alnico Woofers Speakers L100 L88 | eBay $195 plus $22 shipping....

http://cgi.ebay.com/JBL-Vintage-123A...item19c4a157e6 $150 plus $22.75 shipping

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Originally Posted by voice of the theater

Sounds like you have the Altec circumferential style phase plug--not the tangerine. Does this look like what you saw with the flashlight?

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Hi VOTT- Yes, that DOES look like what I was seeing... to be honest, I could not make out the detail of the center area of the plug. But I could clearly see the bright, outer ring with the slots at 120 degrees apart. So I'm inclined to think these are indeed what I have.

Thanks for the info about the L-pads. I may go back at some point and replace them. Put that one on the loooooong list of "things I shoulda done..." Dang!!! I just keep gettin' smarter all the time!

:rolleyes:

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Originally Posted by Corona Blue

.....Dang!!! I just keep gettin' smarter all the time!

:rolleyes:

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That's better than the alternative!:doh:

Does anyone have a copy of the Altec 32343 Network Divider on the wild?

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Originally Posted by LostInTennessee

Does anyone have a copy of the Altec 32343 Network Divider on the wild?

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