Help Identify Resistor

[Krunchy]

Hi guys, I am trying to accurately identify this resistor, I looked up some info on the net but was not able to find the exact one. Colors seem to be Orange, Orange, Green & Red.
This little guy is from my CCX-over from the 4345s and I seem to be having some issues with the horn tweeter and I believe this might be one of the culprits.
I think this is a 3.3m (or 3M3 model# resistor?) Carbon film 1/4 watt 5% resistor but would like some confirmation on this and also, where can I purchase them. I found some 4 band resistors but with a gold body, same color sequence?!
Thanks in advance,

Fred

[quindecima]

3.3 megaohms. Get it at Mouser

[Krunchy]

Thank you Quindecima, Order placed. Hopefully this will take care of the issue otherwise I'll have to do more diagnostic evaluations as to why the horn is not working.
I did run a set of jumper wires from my other speaker's x-over to the one that was not working and when I hooked them up & powered them the horn worked fine so I'm keeping my fingers crossed.
Thanks again! ;)

[JeffW]

3.3 megohms sounds suspiciously like the pull up resistor to feed the biasing voltage to the capacitor junction - I wouldn't think it would cause any of the drivers to stop working.

[Krunchy]

Hi Jeff, I have to confess that all this stuff is like trying to learn Mandarin, totally foreign to me. I started by replacing the L-pads and working backwards, the L-Pads were ok.
When I jumped the wires from my other speaker which was working fine, I connected the white & green terminal wires on the malfunctioning speaker to the "good" x-over and the horn tweeter jumped into life and sounded like it should.
There are some Mills 30 ohm caps there, maybe they are compromised I don't know (nothing looks like its compromised/blown) but I am trying to be methodical about figuring out where the problem lies.

The horn driver on the "bad" speaker was/is working but it was all "broken up/muffled", not clean and lively which is what it sounded like when I jumped the cables from the "good" cross over? There are 4 wires going to the Lpads, black & red to the Ultra high tweet and white & green that fed the Horn tweet, when I hooked it up to the other speakers xover everything sounded fine. with my limited knowledge about all this stuff I'm just trying to figure things out one step at a time.

Any suggestions or thoughts on this are gladly welcomed, I merely want these to be back in working order.
The 2405H L-pad is not in contact/connects or feeds the 2425H L-pad , for all intents and purposes they are independent of each other. the UHF tweet works fine regardless?! Hence my dilemma.

In the pictures below you can see the resistor between the Aeons (under the zip tie) that is the one I suspect may be faulty, this is hooked up directly to the Battery.

Thanks!

[JeffW]

Rather than the resistor, I'd suspect the connection between the two caps might be intermittent where the resistor joins them. I guess that a blown resistor might remove the center connection of the capacitor pair from ground and halve (edit not *double*) the capacitance in that section of the circuit, too, but I'm not sure. You could disconnect the battery and just jumper a wire where the resistor was and see it the driver fires back up - you don't need the battery voltage for the crossover to work.

And there's gotta be some hidden connections under those terminal strips - a lot of components don't appear to be connected to anything.

[Krunchy]

Rather than the resistor, I'd suspect the connection between the two caps might be intermittent where the resistor joins them. I guess that a blown resistor might remove the center connection of the capacitor pair from ground and double the capacitance in that section of the circuit, too, but I'm not sure. You could disconnect the battery and just jumper a wire where the resistor was and see it the driver fires back up - you don't need the battery voltage for the crossover to work.

1 - You mean the connections/fasteners might be loose, I checked them, they were all screwed pretty tight but I could check them again.
2 - you mean use a jumper wire to the Caps without the resistor in line & see what happens?

Excuse my ignorance and thank you for your patience :)

[JeffW]

That should have said "halve the capacitance" instead of "double". Charge couple circuit uses twice the capacitance as the original circuit, but that gets chopped in half when capacitors are used in series to provide a point to apply the bias voltage between them. So if there is no point in between the capacitors to return to ground, you end up with a really wonky smaller value in your circuit (if my reasoning is correct - I might be totally wrong here). But just restoring the ground point between the capacitors should restore the original capacitance value to the circuit. The resistor is just used to keep the current draw from the battery to a minimum, you don't need the resistor - or even the battery - to just test it, but you would need to jumper the connection between the capacitors back to where the resistor was connected just long enough to see if the crossover works again. The caps should block the DC from the battery, so I don't think it'd hurt to leave it in, but I'd take it out for a short test.

[Krunchy]

YOu The Man Jeff! :applaud: :bouncy:
I jumped the wire without the battery (& Resistor)...It Worked like a charm. Then I plugged the Battery back on, same thing, worked fine, horn was singing.
I then re-introduced the resistor and it worked till I plugged the Woofer back on (w/batt on line) & Tweet went out!. Took the Battery out but the horn was still out.
I took the resistor out of the signal path, jumped it again, with the woofer in line and sure enough, everything was running fine & dandy like sour candy. Did the test again with & without the battery and the horn was working as it should.
So, what that hell does this mean, that the resistor is faulty?! Please advise.

In either case you resolved my fricken mess, I cant thank you enough. Next thing I have to address is a ground loop issue, but that's another story, I need to mess around with that for a bit.
I'm playing them at very conservative db levels, is there any chance of doing damage to the drivers this way or should I hold off till I replace the resistor?

Thank you yet again ;)

[JeffW]

It's funny - originally I doubted the resistor could be the issue, but thinking about it and how it could really influence the capacitance of the circuit if open I convinced myself I guess.

So yeah, looks like that one little resistor is the problem - but you had already figured it out before I stumbled along. ;)

I don't think it'll hurt anything to run it with the jumper, other than draining the battery quicker, but I'd sure like a second opinion there.

It wouldn't hurt a thing to run it jumper/no battery.

Ground loops? You're on your own!

[Krunchy]

It's funny - originally I doubted the resistor could be the issue, but thinking about it and how it could really influence the capacitance of the circuit if open I convinced myself I guess.

So yeah, looks like that one little resistor is the problem - but you had already figured it out before I stumbled along. ;)

I don't think it'll hurt anything to run it with the jumper, other than draining the battery quicker, but I'd sure like a second opinion there. (if anyone has any suggestions I'd be open minded to hear them, thank you)

Ground loops? You're on your own!
:rotfl::rotfl::rotfl:
Yeah, that seems to be an ongoing theme with ground Looops.
I have a few ideas about that. Oddly enough I set up a designated circuit breaker just for the 4345s, along w/(5) 8' copper ground rods on a "Technical Grounding Pattern" as per studios set up, hooked them up with the cable in a star commoning pattern on a "commoning Block" . I'll have to figure that little riddle out later.

Thanks again Jeff, I really appreciate all your time and consideration in helping me resolve this issue.

Cheers! :cheers: :homer: :)

[Krunchy]

Just wanted to thank all you guys who pitched in to help me figure this problem out, I truly appreciate it ;)

Fred

[grumpy]

I believe that something else may be (or was) wrong.

The resistor is not there to limit battery drainage per se, but to
allow a voltage swing (the music signal) on top of the DC bias,
and to isolate the various signals at each biased cap intersection
from each other. Shorting the 3.3M resistor quickly forces the voltage
between the caps to be 9v... something an amp would have to work
against to get a signal to pass.

Two caps in series act as half the value. There is no requirement
for a path to ground between them for this to be true.

As correctly mentioned, the battery and resistors are not required for
the crossover to function normally, but you need both if used at all
to provide the DC bias between the pair of caps.

Something fishy is going on. Perhaps an unintentional connection or open.
That the MF stopped working when the woofer was connected is
an indication of this. If it's all working now, maybe the issue was bumped
and intermittent. Worth re-checking your work... maybe with a 2nd set
of eyes.

I'd hate to see this come back and bite you.

[allen mueller]

I believe that something else may be (or was) wrong.

The resistor is not there to limit battery drainage per se, but to
allow a voltage swing (the music signal) on top of the DC bias,
and to isolate the various signals at each biased cap intersection
from each other. Shorting the 3.3M resistor quickly forces the voltage
between the caps to be 9v... something an amp would have to work
against to get a signal to pass.

Two caps in series act as half the value. There is no requirement
for a path to ground between them for this to be true.

As correctly mentioned, the battery and resistors are not required for
the crossover to function normally, but you need both if used at all
to provide the DC bias between the pair of caps.

Something fishy is going on. Perhaps an unintentional connection or open.
That the MF stopped working when the woofer was connected is
an indication of this. If it's all working now, maybe the issue was bumped
and intermittent. Worth re-checking your work... maybe with a 2nd set
of eyes.

I'd hate to see this come back and bite you.

I thought the same thing something else is going on, there's allot of soldier joints and connections in that crossover. Maybe there is a cold soldier joint some were.

Also hard to tell whats going on with out a schematic but in the pics it appears that in 2 places there is bias voltage being applied to capacitors that are in series but are different values. I could be wrong but I thought in CC networks the capacitance on either side of the bias voltage had to be equal value.

AL

[Krunchy]

Appreciate the input guys, right now speakers are going to take a rest till the new resistors arrive. As for the woofer affecting the horn that only happened when the perceived faulty resistor was in place.
Just for the record (& I think its plainly obvious) I did not build these X-overs, these are John.w's clones and I believe the x-overs were made by Mr. G aka 4313B, as we all know he is held in high regard when it comes to all things speaker/electrical/technical. Would be nice if he weighed in.
I'll let you know how things work out when the resistor is replaced, believe me, no one wants to resolve this issue more than I do.

Thanks,

[grumpy]

Yes, a schematic would help :)

and the caps don't have to be the same value,
although same type and order of magnitude in value
is probably a good idea.

[Krunchy]

I thought there was a schematic for the CC Crossover somewhere here in the vault but I was unable to locate it. :(

[JeffW]

I'd like to know how those terminal strips are connected on the bottom side - seems like a lot of components connected to nothing, but the quad wire (L-Pad?) is hooked up the same way, so there has to be something going on.

There are a few different 4345 CC schematics floating around, but posting the wrong one would probably just add to the confusion.
The one in post #5 http://www.audioheritage.org/vbulletin/showthread.php?16967-4345-References-Thread&p=175125&viewfull=1#post175125

appears to have some of the same capacitor pairings - I see a 24/24 a 15/9.1 but no 24/12

[Krunchy]

I'd like to know how those terminal strips are connected on the bottom side - seems like a lot of components connected to nothing, but the quad wire (L-Pad?) is hooked up the same way, so there has to be something going on.

There are a few different 4345 CC schematics floating around, but posting the wrong one would probably just add to the confusion.
The one in post #5 http://www.audioheritage.org/vbulletin/showthread.php?16967-4345-References-Thread&p=175125&viewfull=1#post175125

appears to have some of the same capacitor pairings - I see a 24/24 a 15/9.1 but no 24/12

Thanks for the schematic Jeff, I looked at it and the other one referenced in that post by Heather. Way over my head and I don't have the time to learn electronics right now .:D

[Krunchy]

I was able to replace the resistor this morning, make the connections, fired 'em up and its back in action :bouncy:.
I don't like to mess with all that electrical stuff & thin little wires so I think I will leave well enough alone.

Thanks everyone for all your help, hopefully I wont have to re-visit this thread any time soon.

Now to address that pesky ground loop.

:)

[Wagner]

Beautiful layout
Expensive
High parts count
And all tied together with crappy crimp connections

THAT is you problem(s)

Have someone properly solder all those lugs and spades in the networks and you won't have anymore of these phantom/intermittent issues, I promise

And if you ever need a resister like that again, please PM me. If I am here and I have it in house I will happily drop one in the mail to you. Don't pay shipping for a .10 cent part

I have plenty of 1%ers better than that metal film shown in your photo

You should also consider investing in an inexpensive DVOM so that the next time you THINK you have a bad resister you can check it yourself in about 2 seconds and eliminate a great deal of wasted time and useless speculation

It could also (if you are willing, or want to try) help you find your intermittent connection

You can pick one up good enough for this task for about $5 bucks (I have these all over the house, like pencils and paper):
http://www.harborfreight.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/i/m/image_23332.jpg
Won't hurt to familiarize yourself with this as well (print one out and tape it to the fridge; if you don't like this one there's about a million versions on-line):
http://nearbus.net/wiki/images/7/7d/Resistor_color_codes.jpg

[Krunchy]

Beautiful layout
Expensive
High parts count
And all tied together with crappy crimp connections

THAT is you problem(s)

Have someone properly solder all those lugs and spades in the networks and you won't have anymore of these phantom/intermittent issues, I promise

You should also consider investing in an inexpensive DVOM so that the next time you THINK you have a bad resister you can check it yourself in about 2 seconds and eliminate a great deal of wasted time and useless speculation

It could also (if you are willing, or want to try) help you find your intermittent connection

You can pick one up good enough for this task for about $5 bucks (I have these all over the house, like pencils and paper):

Won't hurt to familiarize yourself with this as well (print one out and tape it to the fridge; if you don't like this one there's about a million versions on-line):


Hey Wagner. Yeah, I was thinking the same thing this morning, aint too crazy about the crimps myself. When I installed the new res to the spade I crimped & soldered it, that just seems to make a lot more sense . If I have these issues again I will remove x-over from speaker, find prob & while its out solder all the spades.

Thanks for the diagram I did "consult" it when I was trying to find/identify the one I had. I ordered a bunch of resistors, I think about a dozen so I should be good for a while on that end, thanks for your offer nonetheless.

When its running smoothly it is a great system but the fact that its bi-amp only has its own drawbacks, sometimes I wish it was just passive and not have to deal with the extra amp & external crossover. I just put in some new gear in place hence the issues. There's something to be said for simplicity, which is something I am striving for all around ;)

This weekend the groundloop, fun fun fun!

[Wagner]

There's something to be said for simplicity, which is something I am striving for all around ;)

This weekend the groundloop, fun fun fun!
Well, you can start by finishing up the assembly job on those networks with a hot iron, some good flux and a little solder

What is the "ground loop" problem? How do you know that is what it is?

Most can be resolved with common sense

Have fun,
Thomas

[Krunchy]

What is the "ground loop" problem? How do you know that is what it is?

Most can be resolved with common sense

Have fun,
Thomas

I thought I had common sense but I wonder sometimes. I don't know if its a proper ground loop, but when there is nothing playing/no signal the speakers emit a "Hum".
What I have rigged up here is actually quite the opposite of simplicity.
Then new amps and Pre amp are mark levinson which use a camac/fisher interconnect, cool little pieces but doesn't mix well with other conventional gear ie: RCA Xlr.
I had to make all the interconnects to hook up various pieces of gear which all (aside from the MK) are XLR, so the interconnects are camac on one end and xlr on the other.

Lots of wires & Tv equipment all next to each other which just aggravates the whole process.
Bottom line is I have to mess with it this weekend & see if I cant figure out what is causing the Hum.

Here's a picture of the Camac ic. this is cam to rca.

[allen mueller]

Yes, a schematic would help :)

and the caps don't have to be the same value,
although same type and order of magnitude in value
is probably a good idea.

Cool, learn something new every day.

Al

[Krunchy]

I believe that something else may be (or was) wrong.

The resistor is not there to limit battery drainage per se, but to
allow a voltage swing (the music signal) on top of the DC bias,
and to isolate the various signals at each biased cap intersection
from each other. Shorting the 3.3M resistor quickly forces the voltage
between the caps to be 9v... something an amp would have to work
against to get a signal to pass.

Two caps in series act as half the value. There is no requirement
for a path to ground between them for this to be true.

As correctly mentioned, the battery and resistors are not required for
the crossover to function normally, but you need both if used at all
to provide the DC bias between the pair of caps.

Something fishy is going on. Perhaps an unintentional connection or open.
That the MF stopped working when the woofer was connected is
an indication of this. If it's all working now, maybe the issue was bumped
and intermittent. Worth re-checking your work... maybe with a 2nd set
of eyes.

I'd hate to see this come back and bite you.

You're right Grumpy, I did find some "oddities" when I pulled out the Cross over. I will elaborate and post some pictures to illustrate. A bit of a mystery still but it could also be my clumsiness.
More to come.

[Krunchy]

Where's Wagner/Thomas? has he been sent on a temporary hiatus?