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OFD
11-27-2004, 09:33 AM
I’ve owned a pair of C56 Dorians (with potato masher tweeters and wood fretwork grills) ever since my parents (the original owners) willed them to me almost 15 years ago. The cabinets have never been opened.



They have served me well and are a beautiful cosmetic addition to my living room as they are in near “mint” condition. The woofers have retained their original white color and, without being able to do a double blind hearing test to compare with today’s technology, I am satisfied with the overall sound quality. They are currently the main speakers in my HT system, where I am using relatively inexpensive Missions for center and rear speakers – no sub woofer for me as I want the main speakers (and surrounds) to be capable of decent bass reproduction. Besides, living with neighbors in a townhouse complex doesn’t lend itself to reverberating floorboards between units.



Questions:



Are they magnetically shielded?



How does one tune (adjust) the crossovers for maximum performance?



Would they (despite their size) perform well as rear speakers in the surround system?



How would they compare to current technology from a manufacturer such as Energy (Connoisseur Series)?



What would their resale value be? The bidding for similar product on EBay is of no real help here, as there are either no bids at the $1500. level and (what I believe to be) over-inflated or false bids at lower levels.



Many thanks in advance for any assistance you might offer.

speakerdave
11-27-2004, 10:02 AM
Are they magnetically shielded?
Yes they are, inherently, because the cast pot magnetic return circuit directs the back field into the voice coil gap, and there is very little stray field.

David

speakerdave
11-27-2004, 10:11 AM
Here is the URL of the 1969 Catalog for JBL home systems.

http://www.lansingheritage.org/html/jbl/catalogs/1969-home.htm

The C56 was a cabinet that could be loaded with various systems. My comments about shielding apply to all of them because that was the Alnico era, but to answer some of the other questions one would need to know what drivers you have.

David

OFD
11-27-2004, 11:51 AM
Many thanks, David.

I bit the bullet and removed the crossover (LX10) to see what is inside.

From all appearances, this is the L101 Lancer (although the lable clearly shows "C56 Dorian"), with LE14A and 1217-1290 speakers. Does this give you enough info to allow you to evaluate what I have, and respond to the other questions?

Thanks again,

Dave

Steve Gonzales
11-27-2004, 12:57 PM
Hi Dave,

The C56-L101's are a wonderful speaker (owned a pair in the 90's). The question of whether or not they "compare" to today's technology is easy. These "old" speakers will smoke most of the "new" fancy speakers, given the proper set-up i.e. electronics-source. Due to insane competition, most of the Great companies have resorted to cost cutting measures and that spelled the end of "mass" produced horn equipped models. Not to offend the "cones" but compression driven-equipped JBL's and other brands for that matter are still the most sought after,desirable and coveted models in the world. I realize not everyone can have a HT and a two channel set-up but IMHO, the C56's deserve to be in a dedicated 2 channel system of it's own, that's where they will truly shine. I have always found most HT set-ups lacking in soundstage, warmth and coherence so I have a dedicated system for both HT and 2CH. As far as adjusting the levels, unless you have the SPL meter, RTA and other critical pieces of equipment, use your ears!. That sounds obvious but I'm not being a smartas*, Ask a friend to help you so he/she can adjust the knob while you are in your normal seating position (sweet spot) and play something you are very familiar with, and have that person adjust the level until you are satisfied. As far as using them for rear surrounds, well, that is like using a Porsche to go only to the Dump. You can do it, but that doesn't mean it's to be done. As to the value, humm, an all original pair in excellent condition has to be worth $12-1500. Ebay is a funny place to sell, it is like the stock market. there are times when prices are up and down. There are 4-6 billion people on the planet and you are one of the lucky ones to own a pair of C56's so they are priceless. Find a nice little tube amp or a well regarded SS (Creek) amp and preamp and a good quality CD player or TT and give these wonderful speakers what they deserve and they will give back an amazing sound in return. If you continue to use them in an HT set-up for whatever reason just know that they are capable of much, much more! I hope this helps you in some way. Happy Holidays, Steve G.


:smthsail:

Zilch
11-27-2004, 02:09 PM
Search the forum for the multitudinous threads discussing "Bypass Capacitors." Your crossovers can be "improved." Here's your crossover schematic:

http://www.jblproservice.com/pdf/Network%20Schematics/LX10.pdf

Looks like only one per crossover will be required, across C1. The bypass gurus here will likely (please?) advise you as to what type and value to use.

Check the surrounds of your LE14A's for stiffness and/or cracks. If they are the original (ivory-color) "Lans-a-loy" surrounds, they will likely need replacement to restore the original bass response of the system; they lose their resiliency over time.

Take them to your local JBL Professional reconer for an accurate assessment. Cracking may only be visible with cone displacement, and the LE14A suspension is inherently stiffer than many other designs, so it takes some experience to know for sure. If he says they need new foam surrounds, have him replace them for you. Should cost about $100 for the pair.

Note: JBL does not sell replacement surrounds, so they'll be using aftermarket substitutes. Chances are pretty good they'll get it right....

OFD
11-27-2004, 05:49 PM
Thanks guys. Steve, my tuner/amp (mid-range Onkyo TD-DS595) allows me to select only the front main speakers (JBL) for stereo and, yes, they do rock at this setting. You have convinced me to hang on to what I had considered to be an exceptional set of speakers, which will remain the cornerstone "Porsches" of the HT and stereo systems. I may consider improving on the center and surround rears but, right now, I'm taking the position of "if it ain't broken, don't fix it".

My first real speakers were a pair of Tannoy 15" monitor gold dual concentrics in monster corner speakers. Believe it or not, I gave them away to a friend when I ran out of space and had won a Technics system in a contest. http://audioheritage.csdco.com/vbulletin/images/smilies/banghead.gif

Zilch, thanks for the link on the crossover but I must admit that this end of the business is a bit over my head. I do notice that there is only one finite spot where sound will be produced when I rotate the crossover dial, and I don't know if this is to be expected or not. Is this perhaps your reference to "improvement"?

The LE14A surrounds are the original ivory color and are relatively soft and pliable, continuing to produce what my ears hear to be exceptional sound. I'll have them evaluated for replacement by an expert if I can find one here. Again, I'm inclined to the above-noted position not to fix something that isn't noticeably out of whack but won't let that stop me if there's a gain to be had.

Once again gentlemen, your input is invaluable and has really helped to put my mind at ease and my ears in cruise control. http://audioheritage.csdco.com/vbulletin/images/smilies/wink.gif

Zilch
11-27-2004, 06:33 PM
I do notice that there is only one finite spot where sound will be produced when I rotate the crossover dial, and I don't know if this is to be expected or not.It is to be expected, but it's not normal operation. Over the years, the operating surfaces in these L-pads have become non-conductive through contamination and/or oxidation. The one spot where they work is where they were set over the years. Simply turning them back and forth many times will often restore proper operation, albeit temporarily.

There are chemical sprays available to assist with cleaning the contacts, but effective use of them may require disassembly. If it remains a problem, the ultimate best answer is to replace the L-pads with new ones. This forum can likely specify a current JBL part number for you, or a recommended generic replacement.

lpd
11-27-2004, 07:25 PM
I had three pairs of these and recently sold two pairs. I have one left and they are super heavy for their size. Really nice sounding speakers, although I'm partial to my L250's :)

OFD
11-28-2004, 09:40 AM
Thanks for the tips Zilch. It all makes sense now, and I've found the name of a place in town here who does JBL warranty work. Understand where you're coming from lpd. The L250s are some serious speakers.

This is one of the best forums that I've been on in a long time. Very well informed members who freely offer their knowledge. Kudos to all, and to all a Happy Holiday.

Dave

OFD
11-28-2004, 12:26 PM
Damn. Here I am, now much better informed, and somewhat smug with my newfound knowledge, and I've forgotten to ask one of the most important questions on getting the most out of my speakers; not just the main, but also the center and surrounds - Mission 73 Series.

Speaker cable. From my searches here, it seems that just about everyone has a different opinion of just what's best, and I really don't want to start a rehash of old cable wars. I'm a KISS kind of guy, so simple is better for me.

While my components are interconnected with Monster type cables, I am using generic speaker wire for my speaker runs. The mains and center are relatively close, but the surrounds are run under the floor for approximately 20 feet, give or take a few. Everything that I have read tells me to use the heaviest gauge wire I can find (which I must admit I haven't done....yet). Monster, of course, say that theirs is the best (at a major premium cost), and I'm not going to go there.

Hence my two questions.

1. What gauge will give me the best results, (single, stranded or twisted) with the least loss and noise?

2. Will bi-wiring the rears produce a noticeable difference?

Realize that I'm off-topic from my original C56 start, but have found your knowledgeable input to be very helpful. I've been on a roll thus far. Why quit while I'm ahead?

Thanks guys,

Dave

Steve Gonzales
11-28-2004, 12:46 PM
I would bet my bottom dollar that if you just stuck with some decent 12ga wire you will be okay. All the hype about cables really drives me crazy. I'm sure that in some super high end cases some small improvement is realized but for the most part, you're just farting in the wind. Bi -wiring isin't going to make a big difference in your system. Bi amping is cool way to set up a system though but overkill in your case. I always like to at least try something once for the experience of figuring it out, but again, you will not realize any or little sonic improvement IMHO. I might suggest that if you ever get your hands on some good 2 channel stuff or have a friend with some to test the C56's with, try that. Just because your Onkyo has a 2ch mode doesn't mean that, that's what pure 2ch sounds like. I can do the same with my Denon 3803 HT, My L220's sound WAY different than they do thru my dedicated 2ch system. As for RCA cable I must say that if you can't make your own (I can), get at least something more than the typical cheap little "stock" cables just for the extra shielding against E.M.I Good Luck

:smthsail:

OFD
01-08-2005, 03:29 PM
I spend a lot of time in here, just reading the volumes of posts and trying to comprehend some of the more technical aspects of your trials and tribulations. To be truthful, I’m completely lost most of the time, but still drawn like a moth to the flame.



Unless I win the L100 raffle which, by the way, I really want, I’ll be happy to carry on with my L101s, with which I’ve had some success. And, to my untrained ear, they sound great. I’m still kicking myself in the ass for missing out on the Mac C34V pre-amp that Dennis Leisz had for sale. My parents originally drove these speakers with a Mac, and I know I would have seen a positive result with this pre-amp.



First, the crossovers (LX10) – I was able to physically access the crossovers easily by simply removing (sliding off) a cylindrical cap (with JBL logo) which then exposed two copper coils, each with a contact pad. The x-over dial turned the coils against the pad. A good spraying with contact cleaner made a world of difference in my ability to tune the speakers, and I’ve now got them set in a middle of the road center point. Take this as coming from a real neophyte, but am I simply increasing/decreasing base/treble response equally as I rotate the dial? Do I then let my ears decide if I want more bass and less treble, or vice versa? Is there not a way to get the best of both worlds; or am I completely missing something here? BTW, the complete x-over assy cover is of heavy duty plastic with screws, and not sealed as someone had earlier suspected.



Second, I have been able to access and download the Operator’s Manual for the Lancer L101 Speaker (a 23 page document) with the critical pages 10 and 11 (placement and adjustment) missing. Does anyone out there have these 2 pages available?



Third, the binding posts are the original spring loaded type where the opening is not large enough for 12ga cable. Interesting that back in production time, very little attention was paid to cable (just use any old lamp cable was good enough). The binding posts are really the weak link in the system. At the amp end, I can just barely squeeze 12ga onto the opening. Should I simply remove enough strands to allow for maximum contact? Or, is there a screw on connector for the cable that would be better? Think I’ll use spades for the Mission surrounds on the HT side, unless this is overkill.



Finally (at least for now) the manual suggests that the walnut surface should only be treated with “wax specifically formulated for use on oiled finishes”. I know I’ve seen several opinions on just what to use on the surface, and wondered if a simple application of lemon oil would be sufficient? There is no apparent drying of the wood and it looks great as is but…………..could it be better?



Not really intending to butter y’all up, but you are one amazing group of people gathered here and I hope to take advantage of your knowledge, expertise and generosity. http://audioheritage.csdco.com/vbulletin/images/smilies/wink.gif

Thanks in advance,

Dave

Steve Gonzales
01-09-2005, 05:21 PM
Hey Dave,

Here is the LHS's original JBL information as to maintaining your C56's
http://www.lansingheritage.org/html/jbl/reference/general/finish.htm

I would suggest another option. If your enclosures are not faded or damaged, use WATCO "Clear", It will do the same thing, just be CAREFUL!! As far as placement: usually there are space/room limitations to consider but I like to start out by placing my speakers in the corners about 1-2 feet from the back and side walls. I'll play some very familiar music being careful to choose some with good low frequency content (Steely Dan's 2 against Nature) and LISTEN at moderate volume. If the bass becomes "muddy", you have too much coner loading so you must move away further from the walls. Corner-loading (half-space) is a technique used for cornerhorns and "in general". The principle is that the back and side walls reinforce the low frequecies. Too much and the bass is BOOMY and unnatural. I would also suggest that you make some sturdy platforms to raise your C56's up about 12 inches. This will place the HF's to a more desirable heigth and if done properly well help the LF too. In a world were there are so many spec's to consider and so many expensive gadgets needed to set up a system, I rely on what i think is the finest instrument in the WORLD: MY OWN EARS!!. I have set-up MANY surround sound systems for friends and family and professionally for years. I recently helped a friend choose a system and one of the best examples of man verses machine is this: He got his new system home and used the "auto level microphone/option" built into the DENON 3805. I got a call from him and he sounded VERY disappointed so I said "Don't worry,I'll be right over. Having the 3803 model, I am very familiar with this line so when I got there, I scrolled thru the level menu and just laughed at what I saw!. I quickly set the levels back to a general baseline starting point and within a few minutes saw his frown turn UPSIDE-DOWN! Try these basic steps to optimize your system. Just remember that a few inches can make a big difference in your sound. Trust your ears! You are unique in your own taste so no "machine" can "tell" you what's right, it can only tell you in which direction to go and diagnose problems faster, ultimately it is your ears that determine "what's right". Good Luck;)

OFD
01-10-2005, 08:04 PM
Hey Steve,


It’s not without a trace amount of envy that I have watched your projects and the fruit of your labor. You, speakerdave and Zilch were quick to reply to my first request for help and here you are again, knee deep in your L220 project, taking the time to offer up some valid suggestions for my setting. Believe me; I am probably singularly responsible for a large number if hits on this site due to my ever increasing thirst for knowledge on how to get the best out of what I have.


If I hadn’t found this site and got your first response, I would probably have dispensed with my L101s and replaced them with something “new”. Thank you.


That LF thud sound you must hear is me kicking myself in the ass for even having had that thought.


I’ve made adjustments here – mostly minor, like cleaning the crossovers, rearranging the rears and tuning the setup for best distance to result ratio. I’ve always had the main L101s 12-15” off the wall, but my real problem is that I have no corners in this part of my living room to play with (just a corner fireplace at one side and my dining room on the other). The speakers are about 72” on center apart so I have taken to locating “me” for the best listening position when I’m serious about what I hear. Your telling me that my 2 speaker stereo selection on the Onkyo can’t touch a dedicated 2 speaker system has only served to keep me looking at the bank account with one eye, and product reviews with the other. This ain’t easy as my crappy CD player is stone age DVD cheap with no redeeming features so, unless I spot a real steal on an amp, I‘ll probably toss some money at a good quality DVD system (Yamaha and Denon are leading the race for my wallet so far) to double up as my CD player.


Then the power will come.


In the meantime, I’ll carry on with the tweaking. I had a look at the “Amazing hi-fi collection” thread and got a great, but simple, idea of how to raise my speakers with a wood block kind of arrangement. This would give me several build possibilities, especially with the ability to play with the LF end at the bottom.


Watco Clear, huh? Spray on, brush on, or rub on? Remember, you are the master refinisher speaking to the unwashed here. Watco have so many choices, my head is only spinning a bit.


Once again Steve – thanks. I know how involved you are with your projects. Mine is just a little puppy, but you treat it with respect. For that alone, I am grateful.


Dave


"It's what you learn after you know it all that counts."

-Earl Weaver

Steve Gonzales
01-10-2005, 09:21 PM
What a great thing to say about us here on the site, that is what it is all about!.
There are so many people with so much information to share, I love it too. As for the question about the Watco: I would take some SUPER FINE steel wool and VERY GENTLY clean the original surface WITH THE GRAIN. When I say VERY GENTLY, I mean SUPER LIGHT pressure, like, "it wouldn't hurt a baby's butt!!. You just want to get rid of most or all of the surface dirt. Then I would dampen a rag with lacquer thinner and wipe them down. Be careful to use the right gloves and do it in a WELL VENTILATED area, away from pilot lights too. This step will remove the wax and grime. You do not want to "soak" the cabs in it, you just want to gently clean the surface. Put the Watco in a very shallow pan and pour about a 1/2" into it. This reason will become evident when you start to work with this very thin product. I use a 2and1/2" wide SPONGE BRUSH to apply the Watco. Get an idea of how much you need to load the brush by testing on a scrap piece of wood. LESS IS BETTER!. Once you get most of the Watco spread out of the brush and there is just a little bit left in it, carefully do the edges. Once the enclosure is covered evenly, let it sit for 20-30 minutes. Use a DARK teeshirt to carefully wipe off the excess with a swirling motion,being careful to push against the wood to ensure even coverage. The reason for the dark cloth is that when I have used white or light material, little pieces get caught in the grain and you have a bear of a time picking them out. If you have access to another junk walnut "something", test this procedure on that first. It's not because I dont trust my technique but because you may want to get an idea of what you will like. Good luck with it and I look forward to your posted results!. BTW, Your C56's have LE14A's so, check out my LE14A restoration tip entitled A bright idea for restoring Aquaplas. Thanks again for your appreciation, Steve Gonzales :D

sgculture
03-08-2005, 06:28 PM
Hi Dave, Steve

I was lucky to own a dorian C56 as well, and am in process of restoring the marble beauty. I have a few questions that hopefully you can help:

1. Best wattage to drive them: I tried using my 2A3 SET amp to drive them. While they sound beautiful, the overall performance esp the bass is not comparable to that of a higher wattage amp using tube such as KT-66/6L6, or EL34. Speaker sensitivity suggested @ 96db is quite efficient, so I am wondering if there is any thing I could do to improve its 2A3 performance. I am using McIntosh C20 as controlling pre-amp.

2. The loudness level at equal volume output differs at 10%. Time to look at the crossover?

cheers,

OFD
03-08-2005, 08:19 PM
Hi sgculture, and welcome to the forum.

I am but a humble student here, but you can rest assured that Steve and some of our senior experts will have some sound advice (sorry for the bad pun) for you. I am driving my L101s with a Denon 3805 at 120WPC and they are not wanting for power. Steve has convinced me that a 2 channel dedicated amp will provide results unlike anything I've yet heard, or imagined.

In my efforts to get the most out of my little beauties, I've turned them into towers by adding a 12" high base unit that gets the sound closer to listening level when I'm seated. I'm now trying multiple locations and positions for the speakers for maximum enjoyment. Mine are also suffering at the bass end and sadly, they will need to visit the shop (not mine, but a pros) to have the LE14As fitted with new surrounds, and the LX10 crossovers are overdue for an overhaul - cleaning and perhaps degaussing.

Good luck with your project. Glad to see someone else here with these great speakers from the past.

sgculture
03-09-2005, 10:22 PM
ok, here a pix of the pair that i am working on...

Steve Gonzales
03-10-2005, 08:55 AM
Well, it looks like those have seen better days and are in need of some TENDER LOVING CARE. The output difference could be caused by several things, one of which is the crossover components. You don't say whether it is the HF or LF or both. Is the problem only in output or does the suspect speaker(s) make unusual noise? Without test gear, the first thing I would do is to swap the drivers to the "good" side and listen for the same problem, this will let you know if it is indeed crossover related. The L-pads are certainly suspect and i would plan on changing them out just to be sure. Parts Express will have a 50 watter that will do. Second of all, the yellow "LANSALOY" surrounds on tyhe LE14a's GOTTA GO!. I've probably stuck my neck out here but, they just don't perform "up to snuff" for me and never have. Be selective in your choice of refoamer's, ask questions about how CLEAN you can expect them to complete the job. Ask around about their reputation!. Next, those poor enclosures need HELP and you can get it right here. Audiobeer is an EXCELLENT refinish man and I've got some good tips for you also. I've done some cool restoration projects and I know you will find all the right stuff here on the LHS. One word about those LE175 compression drivers. These wonderful vintage compression drivers have a exponential value premium if those RED WAX SEALS are left intact!!!!. Don't remove them for ANY reason except for diaphragm replacement!!!!!!. As for your choice of amplification, I'm sure that a nice little tube amp will be just fine. I'm just to the point of experimentation with that type of amp but I'm sure if you start another thread and ask, someone will have suggestions for you. OFD has taken the bull by the horns (pun intended) and worked hard to get the most from his C56's by building some very handsome and equally funtional stands to raise those short lil' babies up and it has benefitted him by getting that wonderful horn up to a better heigth and consequently de-coupling the speaker from floor reflections thereby reducing the boominess. I've seen prototype pictures and they have a JBL style to them to boot!. Welcome to the LHS and I eagerly await to see the step by step transformation of your C56's back to their proper glory. There are MANY trains of thought here from different people. I do not assume that my way is the ONLY way, I can only give advice along the same lines of what I would do if they were mine. I have owned a pristine pair of L101 Lancers that are identical to your C56's. I regret letting them go. I'll keep an eye on your thread. Feel free to send me a PM too if you need help. Good Luck , Steve G ;)

mike
03-10-2005, 06:09 PM
I used to own two pairs of L101's. Since they are a nostalgia piece I think they mate best with the type of equipment that they were likely to be used with when new. The Japanese collectors used to go crazy over L101's. They like them because they are small, they have fretwork grilles and they look unique , and they contain a compression driver/horn just like the large JBL systems. JBL even reissued a more modern version of these for the Japanese market. I believe it was called the S101.

Mike

OFD
03-10-2005, 10:38 PM
These may be physically small, but at 85 pounds of weight, they cannot be called "small" speakers. The upper end is amazing, and a 14" woofer should blow loud and low. Age has taken its' toll on the poorly chosen Lansalloy surround, but are there any other 35 year old surrounds out there that shouldn't be replaced? I'm not convinced that there isn't a better crossover than the LX10, and am open to suggestions.

First though, I'm going to have the woofs resurrounded and the crossover cleaned and retuned (possibly even replacing the L-pads if that will make a difference).

I've no reason to believe that I can't get a pair of extraordinary speakers out of the ones that I already have, and would be hard pressed to get any that are better looking.

sgculture
03-11-2005, 11:43 AM
Steve, Mike, OFD

Thanks for the input. I will certainly take these into account during the restoration.

Just a point to add: I am from Singapore, so while some of your recommended referrals are beyond me, the techical information are very much appreciated. I am looking at the Lansalloy surround and seeking suitable replacement. The carbinets does need some work. I am taking a step by step plan to identify the area of priority.

Mike, you are right about the S101, which is very popular in this part of the world due to its size. ;) Then again, which JBL vintage model has not enjoyed its fair share of success?