Howdy out there; first post here and a question:

I just picked up a pair of Klipsch 3002's, and have scoured the forums already for information.  The internal crossover in one of them is inoperable, the HF out is non-functioning.  [Originally I thought the horn driver was bad and have a replacement for it, but on a hunch, I checked the drive PCB from the other housing in the broken one and the horn started working again.  So obviously the HF channel on the distribution circuit is bad.]

 One friend suggested powering the speakers and tracing voltage along the PCB until I got a dead reading, and then presuming that component was bad.  Is this a viable test method, or how else should I go about testing the board?  Will replacement components be available, or should I just plan on buying a new control board?

Pictures for the fun of it:

The suspect panel with screws already removed

The grille and front

Bottom reinforcement added by the previous owner?

Corner damage. If I have time, I'll reinforce these with rounded metal corners similar to those you find on the roadready boxes.

I plan to follow the 15th post of this thread to help with the "restoration."  (It's more of a function thing than a good looks thing; I just want it to work well first... We'll worry about looks later.)  The idea is to go with a less expensive and portable system similar to JoeyDingo's Beer & BBQ system.

I also have a "Crest 4001 Professional Power Amplifier" that I'll be troubleshooting soon, it has one channel out.  Is this forum an appropriate place to discuss that?  I have little to no experience troubleshooting sound system amplifiers.

 

Thanks in advance,
Stevo

 First thing I found was this dismounted component.  From my limited experience, it's a transformer, yes?  The mounting (silicone) is done, but the piece itself is still attached.  It appears to be on the LFcircuit anyway, so there should be no issue here...

Then I found this connection which appeared to be a little bit long, and might have been touching the hanging component from earlier.  I pared it back..

Here's an image of the board.  Everything appears to be in order - no loose solders, and no obviously blown components.

The other side.

The jacks / fuses.  Yes the fuses are intact, yes, they are the 20A fuses, yes I will be changing them to the recommended 1.5A and 3A fuses.

The boards are messy and dirty, yes - I'd expect that after 25 years of wear.  No obvious problems to my eyes, can anyone with more experience say anything about it?
Stevo

 This might be easier than you think.

 

See that photo with the two yellow capacitors? Next to one is what looks like a little orange disc capacitor. It's a polyswitch and it's the 'KLIP' circuit for the tweeter. Using a wire  (alligator clip test leads work well), jumper around that guy. There is a good chance that in pro use, it's tripped so many times that it's burn out. Sometimes they actually blow apart or one edge is charred but I don't see that here. 

You can get replacements at Parts Express (follow the schematic on other thread to get value), or just bypass it with a piece of wire. 

 

Michael

 Thank you Colter; as long as I watch my levels it will be okay to jumper the KLIP circuit, since it's just a emergency protection limiter, correct?  

So just jumper (short) the small cap out of the circuit... will give it a try tonight.

Thanks.
Stevo

Booyah.

Being artsy...


So I tried bridging (shorting) that small capacitor. It did not solve the problem I began to work through the circuit with a VOM set on ACV. The signal stopped at this connection. As I was probing around the connection, I jumpered the component lead to the solder lump and spooked myself when I suddenly got sound out of the horns...


I added a healthy amount of solder to the lead/solder connection, but it didn't solve the problem (no picture, sorry). I went probing around again, and jumpered the solder to the board during the testing - the joint had come off the board. So I removed as much solder from the connection as I could and scratched a through the insulation on the PCB....


No picture of that result either, but I fired it up, and man does it sound good. Of course, it's after midnight and I'm being quiet so as not to wake the rest of the house, but chalk one up to troubleshooting.

Thanks for the help Colter.
Next on the table I have a Crest Amp that I'll be troubleshooting; would there be people here who can help me through that, and is it appropriate to post about here?
Stevo

 EXCELLENT troubleshooting stevo! You get Crossover Repair Merit Badge for your efforts. We'll toss Photography Merit Badge in there too for your excellent close up shots of your repair job.

It's amazing what we can do with a soldering iron, a little bravery/instruction, and some patience! 

 

WOOHOO! Rock on my Klipsch Brother!

 

Michael

I am having the same problem with a pair of 3002's I bought a few weeks ago. I don't think they had been used in a few years.

I fired the first one up no horn, just a little more volume, horn comes on and stays on all day.

Speaker #2 I fired it up no horn, a little more volume, horn pops on , but this one is intermittant. at high volumes it works good, but it cuts out at low volumes

I pulled out the crossover, but it looks good. Im going to use your pics. to troubleshoot mine, so thanks.

Thoughts?

 

Thanks Colter.

Bobby, I'd put enough signal out of your amp to get a decent bounce in your needle when you measure AC voltage exiting your amp (Red probe to Red out, or positive; Black probe to Black out, or negative). [I have a needle on my VOM because it's an oldschool analog; I'd wager newer VOMs will fluctuate in reading on the display.] When I say "signal" I just used a current pop tune with a lot of fluctuations at all frequencies, that way I'm going to get a good oscillation no matter where I am on the crossover circuit, high or low freqs. I also have a clip to attach on the end of the probes so that I could clip the black probe to the -HF in.
Verify signal across +HIN / -HIN.
Leaving one probe (black) on the -HIN, proceed through your circuit with the other probe (red). from each component to the next, checking for the voltage fluctuations before and after each component.
The place where your voltage disappears is highly suspect - that component, or solder, is where I'd begin your further testing.

Being firm here is, IMO, okay - I'd use that red probe to press on the solder joints, to see if they're loose. I got lucky in that I pressed hard enough to expose a loose solder joint *purely by accident*.
When you do find that disappearance in voltage, I'd suspect the joint where you located the disappearance, and the component before that joint, and the joint before that joint, and the joint after that joint. That's a lot of joints.....

I.e. if your troubleshooting went like this: +HIN (okay) .... joint to transformer (okay) .... joint after transformer (okay) .... joint to capacitor (okay) .... joint after capacitor (NO VOLTAGE HERE) ....
then I would suspect the joint after the capacitor, the capacitor itself, and the joint before the capacitor. check those solders and components for proper values and use resistivity to check continuity.

Note: You could also use pink noise, or a tone track, if you know the tone you're working with should propagate through the "side" of the crossover you're testing.

Best luck. Post how it goes for you....

Same component, same place! i only had to heat it up with a soldering iron, now it works great. I'm going to pull out the other one tomorrow to see if that one will do the same thing. In the 5th and 9th pics that you posted the part labeled CBB61 is different on yours than it is on mine.On mine that part looks like a larger version of the part in front of it. yellow and rounded. Has yours been replaced? does one of your cabinets sound different than the other?

Bobby,

If I had done it right, the same fix would likely have worked for my board, good call.

I can't see evidence of them necessarily having been replaced, but I believe these were from the era when industrial and manual solders looked the same, so much of what I've seen could go either way. They both seem to sound good; although I've been spending time on the amp and acquiring the rest of the setup, so I haven't strenuously tested them.

Good job man.
Stevo

Great info and follow-up guys!

I hope it is something that I'll never have to do, once I figure out how they are coming home to roost in Canada, but take great comfort in the step by step provoded here and elsewhere, thank to you, Colter and many others who have tread before.

This is a little bit out of date, but could still be beneficial to someone.  I bought a pair of these in late Spring and they didn't even have the crossovers in them at all. Neither crossover was present. I bought a couple of Selenium crossovers from Parts Express and mounted them on thin cedar boards high on the inside of the cabs and they are working quite well. The price was under $100.00. These crossovers are heavy-duty gear, substantial and well-made. There are differences in some of the engineering and operating parameters but what my ears hear sounds good. If I had it to do over again, I'd do it the same way. Parts Express also sells crossovers by other manufacturers.  

You have got to be kidding.... no crossover at all?? Insane. So both loads were being driven by the full signal? What were the jacks plugged into, just nothing? That is interesting. Were they bridged internally or simply independently wired, each driver to each jack? Perhaps the previous owner had biamped them.... ? Just a thought.

I would love to hear them bi-amped, and use the crossover from a digital crossover, like a dbx driverack. I'm using mine live in about 10 days on top of my KP-115sw's.

 I'll use the 3002's full range with the Klipsch crossovers. I'm running the subs off of a seperate amp and digital crossover, I will also go through the Klipsch crossovers on the subs just because they are there, I'll probably just send from about 45hz to about 150hz to the subs.

In retrospect, what probably happened is the crossovers and the woofers all got blown at the same time. I bought these in Nashville, a very big music town. On a visit with Townes Van Zandt up there about 30 years ago, I looked in the phone book and there were over 200 recording studios listed in the yellow pages. Big music town. Memphis is the same way. There are risks inherent in the place I found them. The woofers had been replaced with woofers made by McCauley Sound out of Washington state near Seattle. It's a company similar in culture to Klipsch when Mr. Paul was still around, definitely mad-scientist-driven! They spec a little different than the stock Eminence woofers, but with the crossovers I installed and some diligent and careful application of EQ (I like Rane EQ's), it's workable and I did not have to replace the woofers. They were being run bi-amped, and the guy even threw in an older variable crossover made by the Biamp company. I figured they had it that way just to manage the power amplification of whatever rig they had been run in before I got them, and that the inputs had simply been rewired, never imagining the native crossovers would be absent. A little bump in the road, but not disruptive of the grand scheme of things. As I was working on them, one of the terminal clips fell off/out of one of the Eminence HF drivers and I already had a Selenium Titanium driver for my center channel, so I robbed that and put it in the cabinet until I could order a replacement, and I liked the sound of the Selenium driver better than the stock Eminence HF driver in the other cabinet, so I wound up loading both cabinets with the Selenium drivers and am now using the Eminence driver with a short, wide-dispersion horn as the center channel speaker. The Eminence driver is a little bit more prominent in the upper highs, and the Selenium unit is a little smoother, so the overall effect is good, and I may now have a pair of speakers that out-perform what they would have sounded like new. They sound unbelievably good, especially with classical and big band jazz program material. I've got about $500. in the pair now and they sound like more $$ was invested. The grills were bent and rough, paint gone in some places,  but the cabinets themselves were in great shape, so I gently hammered the grills out straight, sanded and repainted with a textured flat back Rustoleum spray paint, and they look right respectable now.