early model 1C's

littlewoodboats

A friend who buys storage lockers found these. He knows he cannot use them without spending money on top of everything else so wants to pass them on to me.

They have two tweets one on top of the other. 2 MW6511 stereo drivers. 2 MW6510 SDA drivers. Dual board crossover with the blade blade IC cable. Cabinets look just like my 2A's only four inches taller. They did not come with the IC cable but those can be made without issue.

Any thoughts on what these might be worth? Any idea what it might cost to rebuild the dual board crossovers or could the boards be swapped for gimpod's units? IF gimpod's units at what cost?

I am not sure I need these but I know I want them. Any booby traps here I should know about up front?

PolkieMan

Wow I would give him $200 in a Texas minute, if they are in good shape. The drivers are correct you need the look at the crossovers to check the components then go over to Gimpod.com and check against his parts list if they match up then we are cool. Here's my beloved 1C pin blade new x-over

Schurkey

Blade/Blade IC sockets will have one terminal NOT connected to anything.

String a piece of wire from the un-used blade to the negative binding post in each cabinet--you're now AI-1 compatible if you can find the mating male blade cable ends. Otherwise, you can use a Neutrik connector or a third binding post--whatever your heart desires. Until then, a single ~16 gauge conductor from (the small?) blade of one cabinet to (the small?) blade of the other cabinet is functional.

http://www.polkaudio.com/forums/showthread.php?131691-2B-and-EARLY-1C-AI-1-modifications

Nice score.

westmassguy

Sounds like a transitional model, with 1B crossovers. Who knows what modifications were done to the two piece crossover to adapt it for use with those drivers.

Schurkey

westmassguy wrote: »

Sounds like a transitional model, with 1B crossovers. Who know what modifications were done to the two piece crossover to adapt it for use with those drivers.

First Guess: 1B STYLE round crossovers, modified or reworked as needed to provide complete 1C circuit and component compatibility.

littlewoodboats

The cabinets are viable but not great by any stretch. The vinyl is shot if they are in anything other than a dark room. The corners were decent with only one needing any serious repair. My understanding is this is not the first time these have sold at an abandoned locker auction.

What was the parts cost for populating the boards? Other than your board shown are there any other electronics in the cabinet?

With the drivers through the series being the same it might be good to upgrade to a single board. But maybe not. TL upgrades do not necessarily excite me but I have never heard a TL'd speaker so may be missing out big time. Ray's SDA handbook does not show the early 1C. I found the image and info I used to verify the ID at gimpod's site.

littlewoodboats

Schurkey wrote: »

Blade/Blade IC sockets will have one terminal NOT connected to anything.
http://www.polkaudio.com/forums/showthread.php?131691-2B-and-EARLY-1C-AI-1-modifications
Nice score.

I thought I had read where just the opposite is the case? I will pull my cable in the morning to verify but I was sure the blade blade used both spades. I know it is correct for my 2A's but these are not 2A's

westmassguy wrote: »

Sounds like a transitional model, with 1B crossovers. Who knows what modifications were done to the two piece crossover to adapt it for use with those drivers.

Gimpod shows it on his site as a transitional. Ray's SDA handbook does not show this particular model.

Schurkey wrote: »

First Guess: 1B STYLE round crossovers, modified or reworked as needed to provide complete 1C circuit and component compatibility.

most likely

EndersShadow

littlewoodboats wrote: »

A friend who buys storage lockers found these.

Your friend doesnt happen to look like this does he?

Attachment not found.

Or maybe this fella?

Attachment not found.

littlewoodboats

EndersShadow wrote: »

Your friend doesnt happen to look like this does he?

Attachment not found.

Or maybe this fella?

Attachment not found.

That fella is the reason we have concealed carry laws in Texas.

EndersShadow

littlewoodboats wrote: »

That fella is the reason we have concealed carry laws in Texas.

LOL... also a fan of Auction Hunters too lol...

tophatjohnny

Great score. You know what to do!!

littlewoodboats

tophatjohnny wrote: »

You know what to do!!

Listen to my fully modded SDA 2A's and be happy?

Malbec

Boatman if you would/could post a pic or two of the speakers and post the serial numbers.

Schurkey

littlewoodboats wrote: »

I thought I had read where just the opposite is the case? I will pull my cable in the morning to verify but I was sure the blade blade used both spades. I know it is correct for my 2A's but these are not 2A's

On a speaker that is INTENDED to use the blade/blade system, both terminals are connected, both conductors in the cable are used. For example, on the 1B and 2A, each speaker cabinet sends a full-range, full-voltage signal to the other cabinet, where it connects to the SDA capacitor bank, SDA inductor, and the negative side of the SDA drivers.

The early SDA 1C and 2B that were built using up left-over blade-blade sockets, only one terminal is connected, and one conductor in the cable is un-used. The "fix" is to connect the other terminal to the negative binding post inside the cabinet.

PolkieMan

The cost of one crossover with new board was about $200.
Schurkey is right only blade is active just like only the pin is active on pin/blade.

Mr. Bubbles

I would get them. Just for the experience. You may love them. I personally would turn them as I unlike most on here, am not a 1c fan and have sold a pair while keeping my 2A's. To me the 2A's are just much better all around. But most others disagree with my opinion on that. Get them and judge for yourself. Keep them, turn them, have fun with whatever you do with them. Either way congrats and enjoy.

rromeo923

My 1C's are blade/blade (w/only one of the connectors connected) and have the dual crossover boards. Trey upgraded my crossovers. At the time Gimpods boards did not support the dual crossover SDA 1C's. That may have changed.
I would jump all over these. First upgrade I would do is get the RDO 194 tweeters.

Schurkey

rromeo923 wrote: »

At the time Gimpods boards did not support the dual crossover SDA 1C's. That may have changed.

First Guess: The Gimpod boards would be JUST FINE in this application, except that you'd have to create some way to mount them in the cabinet.

rromeo923 wrote: »

I would jump all over these. First upgrade I would do is get the RDO 194 tweeters.

I would jump all over these. First upgrade I would do is to refresh the crossovers.

heiney9

I believe if you read Gimpod's disclaimer, it states his boards don't work with the split board models.

http://www.polkaudio.com/forums/showthread.php?133912-SDA-Custom-PCB-s-Round-2&highlight=board

I am not saying they won't 100% work, but they will not be plug-n-play and you'll have to jury-rig some stuff if they even will work.

H9

Schurkey

heiney9 wrote: »

I believe if you read Gimpod's disclaimer, it states his boards don't work with the split board models.

http://www.polkaudio.com/forums/showthread.php?133912-SDA-Custom-PCB-s-Round-2&highlight=board

I am not saying they won't 100% work, but they will not be plug-n-play and you'll have to jury-rig some stuff if they even will work.

H9

They don't work with split-board speakers because--except for the transitional 1Cs--all the split-double-round-board-speakers use the prior-generation of transmitting the SDA signal between the cabinets. There may be other circuitry differences that would make them incompatible also. So, true enough, the Gimpod boards wouldn't work for 1Bs, for example. However, since the circuity is the same between the split-board 1Cs and the rectangular-board 1Cs, and the 1Cs use the latest-generation of SDA transmission, I'd expect the Gimpod boards to work just fine--except for physically mounting them in the cabinets, which will take some cleverness. He'd also have to convert the wire harnesses to use the plug-together (Molex???) harness connectors.

heiney9

Good explanation Schurkey

H9

Malbec

Tony did verify in another thread that his boards would work with the dual board 1C's. One of the low pass inductors has to be rotated 90 degrees in order to be soldered to the board. I'm planning on doing this mod as a retirement project next year. I have everything I need to do the upgrade except new ic sockets and plugs.

As far as mounting the boards I was going to take a close look at the 16mh inductor to see if they would mount on it.

littlewoodboats

Thanks for all of the information. I get nervous when I see the words "transitional model" without understand just what it means.

Looks like the 1C owners club has a new member. I am going to need another set of rings.

JayCee

Malbec wrote: »

Tony did verify in another thread that his boards would work with the dual board 1C's. One of the low pass inductors has to be rotated 90 degrees in order to be soldered to the board.

Steve,

Tony's boards are 100% compatible. Over a year ago I was the first one to use his boards to convert my dual board 1C's. Tony's confirmation Malbec refers to above had the picture of my boards. Tony annotated them with all the correct parts so I'd know where to place them. I used Sonicaps, Mills resistors and converted to a single binding post for the SDA IC. A few weeks ago I upgraded the .40 mH inductors to Jantzen and the 16 mH to Solen. Basic solder skills are needed and honestly, not difficult.

Malbec wrote: »

As far as mounting the boards I was going to take a close look at the 16mh inductor to see if they would mount on it.

Malbec,

I used the plastic spool the inductors come on to mount the new and much bigger Solen. The spool is riveted. Drill out the rivets and the assembly seperates into 2 halves. I centered and hot glued the inductor to one of the halves, then glued the 2 halves together. Drill holes on the second half around the center of the spindel and shoot hot glue down the center and load it with glue. Very solid and I was able to mount the inductor above the binding post cup in the original location of the 2nd board using the original hex screw. The single XO board was mounted to the binding post cup from the inside and hung upside down to make the shortest connection to the 16 mH inductor. Here's a picture:

littlewoodboats

If both of these boards are in 1C's why does the top one have an extra component? (just above the P1 input)

Are there sonic reasons to switch from the dual round boards to gimpod's? should probably have them based on the cool factor alone

Malbec

The top photo is showing the polyswitch which is used for tweeter protection. The other photo shows a jumper in place of the polyswitch.

JayCee

Malbec wrote: »

The top photo is showing the polyswitch which is used for tweeter protection. The other photo shows a jumper in place of the polyswitch.

Spot on...littlewoodboats and I just hung up the phone. The polyswitch/jumper is what he was asking about.

PolkieMan

Yes I used the poly switch and he used a jumper, you can use a resistor see the url below just mouse over the area.
It's a lot easier to build your new crossovers with the new boards and service them in the future should you decide to change anything.

http://www.gimpod.com/partsp1c.html

littlewoodboats wrote: »

If both of these boards are in 1C's why does the top one have an extra component? (just above the P1 input)

Are there sonic reasons to switch from the dual round boards to gimpod's? should probably have them based on the cool factor alone

Malbec

Thanks for posting the pics gents. I've added them to my visual library. I believe I got yours from an earlier post PolkieMan.

JayCee, is that the original location for the 16mh inductor? What gauge wire is the Solens?

Littlewoodboats, I would recommend getting the boards. They make the job practically foolproof.

JayCee

Malbec wrote: »

JayCee, is that the original location for the 16mh inductor? What gauge wire is the Solens?

Yes, the 2d original XO board w/inductor was mounted in this position. The Solen is part # S1416.0, 16.0 mH, 14 AWG, 1.24 Ohms DCR. I believe a few other folks have used this in the CRS rebuilds and I have another set for my future CRS+ project.

Here's a shot of the original crossovers separated from their standoffs. The closest one is the binding post cup:

littlewoodboats

Schurkey wrote: »

They don't work with split-board speakers because--except for the transitional 1Cs--all the split-double-round-board-speakers use the prior-generation of transmitting the SDA signal between the cabinets. There may be other circuitry differences that would make them incompatible also. So, true enough, the Gimpod boards wouldn't work for 1Bs, for example. However, since the circuity is the same between the split-board 1Cs and the rectangular-board 1Cs, and the 1Cs use the latest-generation of SDA transmission, I'd expect the Gimpod boards to work just fine--except for physically mounting them in the cabinets, which will take some cleverness. He'd also have to convert the wire harnesses to use the plug-together (Molex???) harness connectors.

I wanted to thank you for your input to my education. Between what we have covered here and your other thread I think I know what I am headed. JayCee's image below is of a round board unit converted to the gimpod board. If it worked for him it should work for me.

JayCee and I talked about the mounting location. There used to be a round board on top of the inductor up top. Putting a board this big right behind the center line of the bottom pair of MW's would be considered a bad thing, correct? JayCee put his on the back of the binding post cup as that is about as far as he could go without the wires being to short. The wiring harness looks simple enough one could rewire and put it on the floor of the cabinet. Thanks again Schurkey