resistor and polyswitch

[ANWKLO]

What are the purpose of these resistor and polyswitch for please?

http://www.polkaudio.com/forums/attachment.php?attachmentid=40503&d=1243310086

[george daniel]

What did the come out of(speaker type/model)? It does not look like anything I've come across,,but who knows? Is that original,or aftermarket,,sorry I'm not much help,but others will chime in,I;m sure. Good luck.

The poly, is like a fuse for tweeter protection,,but your picture/application looks different,so I'm not sure of the application in this case.

[ANWKLO]

It is inside the crossover from the original Monitor 5A with fuse, Peerless, MW6500 and 8" passive radiator:)

[george daniel]

It looks like someone added that,, your's are fused IIRC,,so no poly was used,,do you have a pic of the actual x-over?.I would remove them if in fact they are aftermarket.Good luck and let us know what you do/happens.

[ANWKLO]

Nobody add that. Here is the crossover:)

http://www.polkaudio.com/forums/attachment.php?attachmentid=40459&d=1243130436

[george daniel]

is there a fuse on the binding post plate?

[ANWKLO]

Certainly, a 1A fuse.:)

[zingo]

Those are extra parts that someone added along the way. I would just desolder them and check to make sure all the stock parts are working correctly. Is that only added to one speakers?

[ANWKLO]

I am the first owner and sure that no modification of the x-over ever. I have checked one speaker only:)

[skrol]

ANWKLO
In an earlier post I thought you mentioned that one of the MW6500 was replaced with a MW6502 by a local dealer. Could they have added these components too? I am wondering if they could have been added to match impedance. Do both speakers have these?

[megasat16]

That seems like a poly cap in series with the resistor for high pass X-over network for the tweeter. I don't think it's a Polyswitch which is different from Poly capacitor and functions differently.

[ANWKLO]

ANWKLO
In an earlier post I thought you mentioned that one of the MW6500 was replaced with a MW6502 by a local dealer. Could they have added these components too? I am wondering if they could have been added to match impedance. Do both speakers have these?


I was there watching the technician to replace the MW6500 with MW6502. No parts were added. Just checked another speaker, also has resistor and polyswitch:)

[ben62670]

That is not stock. Sorry. PDF's are posted here.
http://www.polkaudio.com/forums/showthread.php?t=38755
The resitor would have lowered the impeadance of the speaker.
Ben

[george daniel]

Again,, it does not appear to be stock,, I did not know that polk used the screw/nuts to attach the crossover to the b/p plate,,IIRC they used "standoffs". Is the OP the "original owner of these speakers"? If not,,it sure appears that someone has been in there previously.

[ANWKLO]

That is not stock. Sorry. PDF's are posted here.
http://www.polkaudio.com/forums/showthread.php?t=38755
The resitor would have lowered the impeadance of the speaker.
Ben



I am idiot for the schematic reading. Is the 2.7 ohms resistor used correctly:confused:

[ben62670]

I certainly would not say your an idiot. I would do a little research on what you have there and mod it appropriately. There are plenty of folks to help you out here.

[ANWKLO]

Again,, it does not appear to be stock,, I did not know that polk used the screw/nuts to attach the crossover to the b/p plate,,IIRC they used "standoffs". Is the OP the "original owner of these speakers"? If not,,it sure appears that someone has been in there previously.


What is OP stands for:confused:

[ben62670]

original poster;)

[ANWKLO]

I certainly would not say your an idiot. I would do a little research on what you have there and mod it appropriately. There are plenty of folks to help you out here.


Many thanks:)

[ben62670]

I am pretty much done for the evening, but I, and many others can help to rectify the situation in short time. Stick around:)
Ben

[ANWKLO]

original poster;)


Of course:)

[george daniel]

I think what Ben and myself are saying,is that it appears that someone else has been inside those speakers before you,,hence the question,of are you the original owner. If not,,it might be a good idea to remove the resistor ,etc,and see how they sound. Good luck.

[ANWKLO]

I think what Ben and myself are saying,is that it appears that someone else has been inside those speakers before you,,hence the question,of are you the original owner. If not,,it might be a good idea to remove the resistor ,etc,and see how they sound. Good luck.


I am the original owner and bought them from HiFi shop:)

[george daniel]

So, they were new when you purchased them? Those are 25+ year old speakers.I'm not disputing your statement,,but I have never seen a resistor and poly on that speaker,and I own a pair as well.The mystery continues.

[F1nut]

ANWKLO, as Megasat16 stated, that is NOT a polyswitch, it's a capacitor in series with a resistor.

I don't know a whole lot about that model, but since you bought them new, they must have come from the factory that way. Looks like the factory decided a little tweak was in order. Simple as that.

[george daniel]

So, they were new when you purchased them? Those are 25+ year old speakers.I'm not disputing your statement,,but I have never seen a resistor and poly on that speaker,and I own a pair as well.The mystery continues.

I just finished a search,, and it's a capacitor(film?) and not a polyswitch.

[ANWKLO]

ANWKLO, as Megasat16 stated, that is NOT a polyswitch, it's a capacitor in series with a resistor.

I don't know a whole lot about that model, but since you bought them new, they must have come from the factory that way. Looks like the factory decided a little tweak was in order. Simple as that.


Then, does it match with the schematic of Monitor 5:confused:

[george daniel]

Then, does it match with the schematic of Monitor 5:confused:

not that I can tell.

[ANWKLO]

So, they were new when you purchased them?


Correct:)

[george daniel]

Well,,then,,like Jesse said,,must have been a "tweak" that Polk used/performed,,you certainly seem to have a very unique model/version. Also,,that is a capacitor and not a polyswitch(since you have a fuse).How do they sound?

[ANWKLO]

Well,,then,,like Jesse said,,must have been a "tweak" that Polk used/performed,,you certainly seem to have a very unique model/version. Also,,that is a capacitor and not a polyswitch(since you have a fuse).How do they sound?


Am I lucky or not:confused: They sound airy , bright and tight:)

[OldmanSRS]

That's a .047 uF 5% tolerance cap in series with a 6.8 Ohm 5% tolerance resistor. The intended purpose would be to attenuate or to pass very high frequencies depending on where that is in the circuit.
Greg

[ben62670]

That's a .047 uF 5% tolerance cap in series with a 6.8 Ohm 5% tolerance resistor. The intended purpose would be to attenuate or to pass very high frequencies depending on where that is in the circuit.
Greg

I think the HiFi shop may have done the tweak because they didn't like the sound. It is a resistor, and a cap across the main terminals(positive to negative).

[DarqueKnight]

This may be one of Polk's famous, yet undocumented, "transition" models. Polk's historian and customer service manager, Ken Swauger, may be able to solve this mystery. Send him an email and reference this thread. Ken's email address is KSwauger@polkaudio.com.

[skrol]

In interesting tid-bit. I have a pair of Monitor 5A's with Peerless tweeters that I just bought from the original owner. He said that they are all original (except for a mod to the stands) and I believe him. My XO's are a little different from ANWKLO's in that his have a 6.2 ohm resistor in series with the tweeter and mine has a 2.5 ohm. I don't know if mine have the RC network in the cup. Photos of ANWKLO's XO and mine can be found in this link:

http://www.polkaudio.com/forums/showthread.php?t=83521

His were built in 1979 (stamped on MW) and mine in 1983. The resistor values seem like a significant change. Could it be due to different Peerless tweeters? Mine are the USA version.

[skrol]

I check my Monitor 5A's and they do not have the extra RC network. I did find it interesting that the XO cups were signed by, I presume, the builder. It is a good sign of pride in their work.