Studio 1C's Rebuilt

WastelandWand'r

Recently, while staring at my 1C's and looking at everyone else's on the forum, I started to develop some deep rooted issues with them.

I had not touched them since picking them up last fall, and felt more then satisfied with the sounds they made. I started searching and reading '1C crossover upgrades' and soon it was apparent that I was listening to second rate loudspeakers hardly worth being placed in a landfill.

Something needed to be done, and thankfully Soniccraft had their 20% off sale.
After breaking the news to the family that dad needed some new parts and that they would be eating ramen noodles for a while longer, I placed the order for new caps, resistors, and a roll of Cardas quad-eutectic solder.

I prepped it by printing off photos of completed crossovers from recent threads, thread discussions, and had my own camera handy to document things as I went along.

The parts came and with it the realization that my attempts at passing myself off as, 'someone in the know' when it comes to electronics was a poor acting job at best. My wife laughing as I nervously removed the passive radiator was of no help at all. She wanted to know why I was sweating and trembling and swore I would make a **** surgeon. (She is my biggest fan)
It was with much relief when I saw that there were quick disconnects for all the driver wires. Hey this was starting to look easy!

I set the crossover onto the workbench, which in my world is the kitchen counter, and got to work. After removing several parts, I realized my first mistake, which was taking more than one part off at a time. Thankfully I had taken some photos of the crossover before removing it from the speaker, so I figured it out, very slowly.
I know someone will probably recommend that I should have just consulted the schematic for guidance. Let me stop you and save the typing as those are written in a language quite foreign to me. I do leave them laying around the house for conversation starters however.

Back to the project. After about 3.5 hours I had everything back on except for the polyswitch and bypass cap which threw me for a loop. Thankfully I found out that F1 was still up and he walked me through it. I re-installed the crossover and powered them up. No smoke!

The next day things went much smoother and it only took about an hour for the second one.

I have been told there is a substantial amount of burn in so I have not done any critical listening. It has not been a detriment that I can tell, and am looking forward to things getting settled in and stabilized.

In closing, thanks everyone for posting their experiences, and especially photos as they were a big help. And thanks again F1.

Happy Trails,
Nathan

WastelandWand'r

I did notice that the polyswitches were different shapes and different colors. Also, one of the 4.4 uf caps was swollen/bulging on one end, while one of the 12's was discolored, and had an odd appearance on one end. All in all it was probably time for a swap anyways.
Nathan

WastelandWand'r

If anyone is thinking of doing this I have one suggestion. When double stacking the 2-20's, do not crowd the coupler for the wire leads. I did not see that I was, and it was touch and go trying to get the connections back together with my arms stuck inside the speaker and trying not to snap the board in half. It made some ominous creaks while I swore at it.
FYI.

F1nut

Recently, while staring at my 1C's and looking at everyone else's on the forum, I started to develop some deep rooted issues with them.

LOL

Quite the entertaining write up, thanks!

george daniel

WastelandWand'r wrote: »

If anyone is thinking of doing this I have one suggestion. When double stacking the 2-20's, do not crowd the coupler for the wire leads. I did not see that I was, and it was touch and go trying to get the connections back together with my arms stuck inside the speaker and trying not to snap the board in half. It made some ominous creaks while I swore at it.
FYI.

LOL been there-done that on my first set too. Nice work sir.Keep us posted as to their progress/burn in.

gdb

That is very impressive looking workmanship!:D

If it isn't too impolitic, may I ask what the outlay for parts totalled?

thsmith

Great job Nathan ! It only gets better from here out.

NotaSuv

Looks great..nice winter project..

Conradicles

Good job and more polkies should do these mods. It is really fun. Enjoy.

chandler9a

Very nice, you are a brave man who has given me hope in someday doing mine.:)

WastelandWand'r

Thanks everyone.

GDB, not impolite at all, the grand total with the solder was $267.21 with shipping to the other side of the world, (Bethel Alaska). The solder was $44.00 so if you don't need it you are looking at about $200.00 with the 20% discount.

I used sonicaps all around, which is the spendy option. It has been discussed that there are other options for the low end which are a little less expensive.

I figure that the pound of solder will last me several lifetimes at this rate.

Nathan

MillerLiteScott

Nice Job!

I found the Sonicaps to be reasonably burned in after about 100 hours +/- and then they really sounded great after 400+/- hours.

Scott

gdb

I'd like to do the XOs in my SRS2s just the way you did your 1Cs, my problem is that I can't read the printing on the schematic sticky thread to know if they use similar parts or not. I hope they do, and that my costs will be close to what yours were, with my luck.....mine will cost DOUBLE. With Polk's impeccable consistency and record keeping in mind.......I wont be sure until I pull the XOs anyway, then I'll know which parts to order for sure.:)

heiney9

Nice work! You are going to LOVE your 1C's.

H9

WastelandWand'r

I am looking forward to it. I really have enjoyed them in the house. Because of the housing situation they are really not set up properly for the SDA effect. Small apartment with little room for them. Even without it I really do enjoy them.

While looking around inside of them, I noticed that the SDA interconnect was very loose (wiggled the pin receptacle with my fingers adn thought it was going to fall off) and will think about replacing them, along with the cord. I have ordered some dampening material and have mortite, but am trying to spread it out to have some fun during the dark months of our winters.

Spiking them along with shoring up the bases somehow are also in the plans.

Currently they are sitting on carpet, and thick carpet at that.

Nathan

dcmeigs

Hey Nathan,

The workmanship looks first rate. Congratulations. Very good point you make about crowding the couplers. I did the same thing. Allowing a quarter inch clearance makes life a lot easier.

Did those speakers come through Camas?

WastelandWand'r

DC,
No, I found these in all places of Fairbanks, AK. $250.00 for the set so I thought it would be criminal not to buy them and give them a good home.
However, I do have a set of 2.3TL's and 2B's in the hills behind Brush Prairie waiting for me.

Hope that sailing worked out for you.

Nathan

WastelandWand'r

Well since the time that I upgraded the X-overs, I have had some free time and pulled all the drivers, welded the magnets into place (noticed several of them had shifted ever so slightly), dynamatted the drivers and PR, mortited the seals, bumped into someone who described himself as a 'machinist' and for a nominal fee got some custom made, at least to me, brass spikes for them. In McGrath Alaska of all places!!
I am not one to wax eloquent, but all of the modest tweaks have brought them to life. The sound is coherent, and on proper recordings do that neat trick of pushing everything away and keep you rooted to the spot listening to music.
With the spikes, I am constantly thinking I have left the sub on or forgot a setting and am listening in 2.1. Nope, they just have the goods to dig a little bit deeper and more convincingly.
All in all, not bad for about 600.00 and some of my time.
Thanks everyone againg for posting the information and fielding the questions.

Happy trails,
Nathan

geoff727

And just think.....you have, like, 5 other pairs of Polk's to do this to now! 'Cause once you do the first pair, the bug hits and doesn't go away. Then it's Ramen noodles for the next 5 years.:rolleyes:

Take care!
Geoff

hearingimpared

WastelandWand'r wrote: »

Well since the time that I upgraded the X-overs, I have had some free time and pulled all the drivers, welded the magnets into place (noticed several of them had shifted ever so slightly), dynamatted the drivers and PR, mortited the seals, bumped into someone who described himself as a 'machinist' and for a nominal fee got some custom made, at least to me, brass spikes for them. In McGrath Alaska of all places!!
I am not one to wax eloquent, but all of the modest tweaks have brought them to life. The sound is coherent, and on proper recordings do that neat trick of pushing everything away and keep you rooted to the spot listening to music.
With the spikes, I am constantly thinking I have left the sub on or forgot a setting and am listening in 2.1. Nope, they just have the goods to dig a little bit deeper and more convincingly.
All in all, not bad for about 600.00 and some of my time.
Thanks everyone againg for posting the information and fielding the questions.

Happy trails,
Nathan

Very cool Nathan. The brass spikes are amazing aren't they. BTW I just wanted to commend you on the job you did on the crossovers, very neat and the components are well placed. I tell can Jesse had some kind of hand in it LOL!!! Congrats Bro.

george daniel

Great write up.Gets a little crowded in the kitchen around supper time eh? I know the feeling;)Fine work sir,,indeed---enjoy,, might I ask,,any tubes?
Have fun--great job.:)

Toolfan66

Looks Good..

Enjoy, can't wait to fire mine up as well..

WastelandWand'r

Geoff, yes, I am a hoarder and will someday get to those other sets. Hopefully sooner rather then later. Just have to learn some of those skills you have with regards to refinishing them.

No tubes. I do own a HCT/HTC? integrated that came with a ipod dock, but it is at work making music there. It did sound really nice matched with the 7's.
I feel like I will have to wait until I am a little closer to the civilized world to start playing with those (tubes).

I have been staring long and hard at Pass products lately (used). Again, only because I read this damn forum. And to think I was completely satisfied with my 10's and my 10 year old Denon receiver a short while ago.

Nathan

heiney9

I have one of those HCT's in my office rig running a pair fo modded 5B's...............very nice sounding little unit.

I can highly recommend Pass products, among the best I've ever heard. Most aren't common ground, so either build a nice AI-1 interphase or do some research. The Aleph line is common ground (non-mono blocks) but the X series is NOT common ground. Of course the Aleph line is discontinued so you'd have to go used the First Watt stuff isn't designed for multiple driver speakers.

H9

P.s. Realized you have studio versions..........not sure the AI-1 will work with those. Shoot me your seila numbers and I'll check when I get home.

WastelandWand'r

H9,
Serial numbers are L9452 R8394. I believe they fall out of the range of numbers but appreciate the confirmation.
I really liked the 7/HTC combination, just too big for the office that I share with 3 others.
Nathan