First QLS-1 comes out for cleaning and serious look.

[7.62]

Ok, found some units with the same rating and going to order 6 pieces today.

Chef & tubed, to run them wide open what resistor value would I need to try it, same deal ? 5 watt/25 ohm. And that would just be soldered in between the 2 wires that were hooked to the pot.

And would it matter on the type, sandcast or maybe a green Mundorf type.

Infinity was pretty generous with the wire so I can test the upper midrange and emits without putting everything back in. I don't have any measuring stuff other than my multi meter, just ears.

 

[slimpikkins]

What units have you found. The info would be helpful.

 

[7.62]

Slim, I don't know how to link it. On the auction site if you try this, should come up. What do you think....OK or no.

5 ohm 25 watt taper potentiometer
Jameco_electronics

 

[tubed]

You want 5 ohm 25 watt.
As to bypassing, you could bypass with a resistor of choice, or no resistor at all, just to see how it sounds without the pot.
With the original potentiometer, Infinity invites you dial in from zero to five ohms resistance.

 

[chef free]

Here's one: http://www.ebay.com/itm/25W-10-OHM-...eter-Rheostat-Variable-Resistor-/130697073925

I've been using the EMITs at full volume so I could see just wiring out the tweeter pot, but the domes need some trim and the midbass needs MORE trim than a 5 ohm pot can provide. I was wondering about getting one of these for the midbass: http://www.ebay.com/itm/25W-10-OHM-...eter-Rheostat-Variable-Resistor-/130697073925

 

[7.62]

Sheeesh, I typed that backwards. Your right, 5 ohm 25 watt.

Right now I'm getting somewhat upset, been online for most of the morning and finding the same value resistors and caps is like pulling teeth.

Yellow Caps.
2.5
1.75
13.6
Nobody makes these values anymore, fricking unobtainium.

The sandcast, cement resistors, 25 watt 5.4 & 2.7, fricking unobtainium

The inductors, 20mh, fricking unobtainium.

The only thing I can find is the 5.0/6.5 mH inductors and the 40mfd cap. That's it. I'm going to take a damn nap.

 

[chef free]

No need to replace the yellow film caps on the EMITs and domes, they last a long time and are part of the infinity sound. If you really want to replace them you can combine lower values.

Here's the 20 mH I used: http://www.parts-express.com/erse-super-q-20mh-16-awg-500w-inductor-crossover-coil--266-960

 

[slimpikkins]

2.7 ohm 25 watt resistors on eBay. Just bought a pair...

 

[7.62]

Thank you Chef & slim, I don't want to change the sound. Guess I got off track thinking I would change everything out while in the first one and compare between the 2.

The generations after we're gone when it's time to replace this stuff are going to have fun aren't they.

I found these, pretty expensive. If you guys don't mind could you take a look and see if these are close.

Elliott Electrical Supply.com
OHMITE 5ohm 25watt Rheostat

They look like the same gizmo just different name, is a Rheostat the same thing as a potentiometer?

Ok, guess they're not the same. Watched a few videos on YouTube. BUT....looking at the crossovers, the tweeters and mid-bass coupler only use 2 contact points, the midrange uses 3 points of contact. So essentially are the tweeters and mid-bass potentiometers being used as Rheostats, and the midrange is being used as a potentiometer?

If that's the case I should be able to use the Rheostats and out of the three potentiometers I have hopefully one I can rebuild/save to use as intended with 3 contacts. Actually of the three, the mid-bass is pretty clean, I think just a quick deoxit and lube would do and I could move it over one position to the midrange.

And chef, I guess that's an option but as slim mentioned it's open in the back. I live in a pretty dry climate with low humidity so I wonder if I'd have to worry about it ?

 

[slimpikkins]

The open back will let poly full and dirt fall in there so it will need to be covered. Even the stock ones should be wrapped in electrical tape as there are holes in the sides.

 

[chef free]

The open back will let poly full and dirt fall in there so it will need to be covered. Even the stock ones should be wrapped in electrical tape as there are holes in the sides.

Don't cover those holes, they are heat vents. Since the pots are resistors, they convert the electrical energy into heat. Try touching one of the shafts after playing lots of loud music, it's surprising how hot they get!

 

[slimpikkins]

Thanks chef free but mine were covered with electrical tape from factory. I was the only guy ever in there for sure.

 

[Bucky Badger]

 

[tubed]

I've never thought of a potentiometer function as being a dissipator of heat.
Ones amplifier, if not functioning well, could supply that heat but DC offset to the speaker would have to be off the chart?

 

[7.62]

Well I ordered the last 2 Ohmite 5 ohm 25 watt Rheostats from Elliot Supply. One each will replace the tweeter potentiometer in each speaker so they match. The remaining potentiometers I've formed a different plan of attack to rebuild, going to try an automotive hose clamp around the ceramic body while I rivet the pins back in, fingers crossed.

The rest of the crossover parts really look Ok to me so I'm going to rearrange the chokes to cover any crosstalk, re-glue all the loose parts and put them back in.

I'll post some pics of the potentiometer rebuild if the clamp method works.

Tubed, I see you changed all the caps, how did it affect the infinity sound ?

Well crap, was going thru my junk drawer and found my torn apart Kappa 8 crossover boards, they have 3 potentiometers, all marked 5 ohm. The polygraph if I'm reading the Kappa 8 schematic right rates that potentiometer at 5 ohm 30 watts. I'm thinking that might work in the tweeter circuit?

 

[7.62]

Here's how close I was then snap.

 

[tubed]

^^^^^^^^^
I noticed the sound tightened up, more cohesiveness.
I'm sure the point to point wire harness helped also.
I kept the big cap for if I ever get a hold of a capacitance/esr meter.

 

[7.62]

Well after this little potentiometer adventure. I'd buy the 5 ohm 30 watt Chinese units. I'm no Speaker expert but the original's are no longer available and I don't think the extra 5 watts would hurt.

My Ohmite units came today and they are open back, I couldn't tell from the pic. But they are the exact value. For the price of two I could have bought 6 of the Chinese and ran with it.

I'm really hoping to clean the remaining ones the best I can, but admittedly I'm disappointed .

 

[tubed]

Well after this little potentiometer adventure. I'd buy the 5 ohm 30 watt Chinese units. I'm no Speaker expert but the original's are no longer available and I don't think the extra 5 watts would hurt.

My Ohmite units came today and they are open back, I couldn't tell from the pic. But they are the exact value. For the price of two I could have bought 6 of the Chinese and ran with it.

I'm really hoping to clean the remaining ones the best I can, but admittedly I'm disappointed .

I've opened up quite a few speaker cabinets that used polyester fiberfill and have never encountered much if any dust or debris.
If there's no rust/humidity issues, most crossovers I've come across look rather new.
Cabinets with fiberglass, a different story.
I doubt if the open-backed Ohmites would be a real problem or I'd find a away to seal them.

We used to put x-over boards placed in sandwich bags in the door wells of our cars and trucks where water and road dirt could be a problem.

ADD> Acoustic Research used to place a piece of cheese cloth between the fiberglass fill and the woofer to keep dust from the voice coil.

 

[7.62]

Well, definitely some improvement replacing the 2 pots. All of the emits are working and can be adjusted though very subtle. I used the Ohmite unit in the mids & the 5 ohm 30 watt unit from the Kappa 8 board on the emits. Had to drill 2 new holes in the plastic plate to make it all fit and resolder.

I couldn't save the original pot in the mid, one pin was so corroded after drilling it snapped with the first tap of a punch. With an automotive clamp wrapped around it. I think they could be saved, with a drill press and press for resetting a new pin carefully, I don't have either.

The bad news is, I think I need a trip for a hearing test. Lastnight I couldn't sleep. Got up and War Dogs was just starting on HBO. I turned on the amps, preamp and settled into the couch to watch. The wife came out and says babe your shaking the walls, those......Watkins are really working well after the refoam. It was comfortable for me, I had no idea I was bothering anyone.

Great movie if you haven't seen it !

So I'm off to get into No# 2, the emits are out, the pot has to be worked back and forth pretty hard to pickup the signal to come back. I'll post a pick of the plate when I'm done.