Home Theater Problems

[mulhearn1022]

After pulling my Polk Audio RMDS-1 system out after months of storage, the sound it produces is extremely distorted after being played at an average level. I suspect that the proper electrical output is not being produced. All the channels, including the subwoofer, become completely inaudible and distorted as the volume increases. I have tried both analog and digital inputs. I have also tried my speakers and subwoofer with another amplifier and they work just fine. I have to play the system with the subwoofer turned all the way down (-10dB) to listen to it without hearing the subwoofer clipping. Again, I suspect the lack of power being output to drive the subwoofer to cause this. I had the system brought into an audio repair shop after replacing the 8A fuse with a 20A fuse to see if that would also blow. I heard from the shop that the 20A fuse was blown when they got it. I suspect the problem lies in the transformer, but am not entirely sure. Is there anywhere I can test on the transformer to check if its working properly? Also, if the transformer is the problem and polk no longer supplies parts for this model, will I be able to fix it?

Transformer Pictures:

(I can't post them yet since I don't have 5 posts, but if you would like to see them PM me until I can put them up here)

If any additional information is necessary, please let me know and I will get back to you ASAP. I appreciate any help you guys can give me!

 

[TLS Guy]

After pulling my Polk Audio RMDS-1 system out after months of storage, the sound it produces is extremely distorted after being played at an average level. I suspect that the proper electrical output is not being produced. All the channels, including the subwoofer, become completely inaudible and distorted as the volume increases. I have tried both analog and digital inputs. I have also tried my speakers and subwoofer with another amplifier and they work just fine. I have to play the system with the subwoofer turned all the way down (-10dB) to listen to it without hearing the subwoofer clipping. Again, I suspect the lack of power being output to drive the subwoofer to cause this. I had the system brought into an audio repair shop after replacing the 8A fuse with a 20A fuse to see if that would also blow. I heard from the shop that the 20A fuse was blown when they got it. I suspect the problem lies in the transformer, but am not entirely sure. Is there anywhere I can test on the transformer to check if its working properly? Also, if the transformer is the problem and polk no longer supplies parts for this model, will I be able to fix it?

Transformer Pictures:

(I can't post them yet since I don't have 5 posts, but if you would like to see them PM me until I can put them up here)

If any additional information is necessary, please let me know and I will get back to you ASAP. I appreciate any help you guys can give me!

The power transformer is the least likely component to have failed.

Since you have distorted sound on all inputs, I suspect there is a plus minus power supply and one side is down and taking too much current and blowing the fuses. And by the way never fit a larger fuse, that is not productive, very dangerous and will do more damage to an already damaged unit.

The fault though could be in any section of the unit, as there may be a fault in any board , such as a broken down power transistor drawing too much current from the power supply.

You can not fix electronics with a shot gun approach of guessing. You need equipment and expertize to isolate the fault to know which components to replace.

Now I will be brutally honest. I down loaded the manual and the only thing that unit needs is a trip to the recycling center.

That unit was a waste of materials the day it was built. There is absolutely no reason to put any time money or effort into it, in fact every reason not to. If it is fixed it would be converted only to working junk.

The unit is about 20 years old and absolutely of no use whatever in today's AV environment.

Do yourself a favor and drop it off at the nearest recycling center.

 

[Nestor]

After pulling my Polk Audio RMDS-1 system out after months of storage, the sound it produces is extremely distorted after being played at an average level. I suspect that the proper electrical output is not being produced. All the channels, including the subwoofer, become completely inaudible and distorted as the volume increases. I have tried both analog and digital inputs. I have also tried my speakers and subwoofer with another amplifier and they work just fine. I have to play the system with the subwoofer turned all the way down (-10dB) to listen to it without hearing the subwoofer clipping. Again, I suspect the lack of power being output to drive the subwoofer to cause this. I had the system brought into an audio repair shop after replacing the 8A fuse with a 20A fuse to see if that would also blow. I heard from the shop that the 20A fuse was blown when they got it. I suspect the problem lies in the transformer, but am not entirely sure. Is there anywhere I can test on the transformer to check if its working properly? Also, if the transformer is the problem and polk no longer supplies parts for this model, will I be able to fix it?

Transformer Pictures:

(I can't post them yet since I don't have 5 posts, but if you would like to see them PM me until I can put them up here)

If any additional information is necessary, please let me know and I will get back to you ASAP. I appreciate any help you guys can give me!

Powering it up with a 20A fuse in place of the nominal 8A may have made things worse.

Unless it has sentimental value, it's probably more cost effective to buy a new one.

 

[mulhearn1022]

Buying a new home theater system is currently out of the question as I'm a broke college student. Were it possible, I would love to buy a new one with the help of this community.

But anyways, I currently have two of the front speakers from this system hooked up to my 40w per channel outputs from my Logitech Z-2300 computer speakers and they seem to be working fine. I make sure not to put the volume too high so they don't clip or anything. I know my old satellites to my z-2300 were 8ohm speakers before I blew them out at a party by playing them too loud for too long and they overheated. So, my question is, is it okay to use these 4ohm RMDS-1 satellites with my z-2300?

Also, being in the financial situation I am (and not necessarily needing HDMI, DTS, etc...), would it be worth it to get this RMDS-1 repaired for like $200 tops?

 

[TLS Guy]

Buying a new home theater system is currently out of the question as I'm a broke college student. Were it possible, I would love to buy a new one with the help of this community.

But anyways, I currently have two of the front speakers from this system hooked up to my 40w per channel outputs from my Logitech Z-2300 computer speakers and they seem to be working fine. I make sure not to put the volume too high so they don't clip or anything. I know my old satellites to my z-2300 were 8ohm speakers before I blew them out at a party by playing them too loud for too long and they overheated. So, my question is, is it okay to use these 4ohm RMDS-1 satellites with my z-2300?

Also, being in the financial situation I am (and not necessarily needing HDMI, DTS, etc...), would it be worth it to get this RMDS-1 repaired for like $200 tops?

No, that system is not worth putting $200 into. You won't know it will stop there. A tech might use up your budget in shop rates and still not have the problem figured out and you would still have to pay the tech his time. Having done most of my own tech work, I can tell you a unit like that will be a service nightmare. In general really good stuff is the easiest to service and junk the worst and not worth it.

I would continue the way you are using the logitech system.

 

[adk highlander]

Take TLS's advice and don't invest in the Polk. For $200 on ebay you can find a much better receiver and also have a few new features for good measure.

 

[mulhearn1022]

Also, I just noticed that on the transformer that one of the capacitors appears to be blown. The top is bulging upwards. And the two pairs of capacitors don't match in specs. I'm not saying that they should but my guess is that they should all be the same type? I guess now would be a good time to mention that I am NOT the first owner of this system. It appears that this board has been taken out of the sub enclosure before, since one of the bolts holding it in was missing a rubber washer. Here's a link to the album:

http://imageshack.us/g/526/hpim1965v.jpg/

It appears as though the blue capacitor towards the middle is blown, as it is bulging. Can anyone more knowledgeable confirm this for me?

Also, the capacitor specs are as follows:

Blue - 15,000uF, 35 WV
Black - 10,000uF, 50WV

 

[mulhearn1022]

I appreciate the advice guys. Now, if the solution to this system's problem was the capacitor or another cheap component on the board, do you think it would be worth it to keep this system so I could also have a sub with my satellites instead of buying a new receiver and just having satellites? I like my bass lines and I will be listening to music with this system so I feel a subwoofer is necessary for any system of mine.

*EDIT: BOTH of the blue capacitors are bulging and soft on the top. Would this explain one side of the power supply taking too much current, TLS?*

 

[TLS Guy]

I appreciate the advice guys. Now, if the solution to this system's problem was the capacitor or another cheap component on the board, do you think it would be worth it to keep this system so I could also have a sub with my satellites instead of buying a new receiver and just having satellites? I like my bass lines and I will be listening to music with this system so I feel a subwoofer is necessary for any system of mine.

*EDIT: BOTH of the blue capacitors are bulging and soft on the top. Would this explain one side of the power supply taking too much current, TLS?*

You just can't guess at long range. Obviously those caps need replacing. The question becomes did those failing caps cause other problems? How much more damage did you do putting in a 20 amp fuse? Likely quite a lot.

Very likely there are other problems then the bulging leaky smoothing caps.

Electonic components are very complex, and I can say nothing definitive unless I had the unit in my bench attached to a battery of test equipment. That would include the ability to run the unit from the Variac at low voltage, so you have a chance of not adding to the problems during service.

That unit is of an age and quality that it is not worth wasting any time and money on.

What did the tech say who confirmed the blown 20 amp fuse? I bet he was not enthusiastic about putting any time into that unit. Did he have any advice for you?

The other issue is: - Does Polk still have a circuit and service manual for that unit? A circuit is essential for service unless you are very lucky. Generally forget trying to fix something you don't have a circuit for. A factory service manual is an extra bonus and usually very helpful.

 

[mulhearn1022]

The tech was actually a younger employee, so he really didn't have much to say about it. But as I was speaking to the owner, he was saying just as you have that I shouldn't put anymore time or effort into this system. I already spent money getting it fixed and they really didn't even fix the problem, apparently they thought they did. So I figured I was going to bring this unit back in on Monday and tell them the problem was not fixed and see if they could actually fix it since I already spent $100 getting it "fixed". Since I have already put this much money into "fixing" it, do you think its worth it's worth it to show them these capacitors and have them run any necessary tests to see if they could fix it at a decent price? I could tell they didn't take this part out of the subwoofer so they most likely did not see it.

 

[TLS Guy]

The tech was actually a younger employee, so he really didn't have much to say about it. But as I was speaking to the owner, he was saying just as you have that I shouldn't put anymore time or effort into this system. I already spent money getting it fixed and they really didn't even fix the problem, apparently they thought they did. So I figured I was going to bring this unit back in on Monday and tell them the problem was not fixed and see if they could actually fix it since I already spent $100 getting it "fixed". Since I have already put this much money into "fixing" it, do you think its worth it's worth it to show them these capacitors and have them run any necessary tests to see if they could fix it at a decent price? I could tell they didn't take this part out of the subwoofer so they most likely did not see it.

So they charged you a minimum service charge for confirming a blown fuse! That was a bit steep, but they are entitled to. It could also have been the passive aggressive way of telling you to get the POS out of here and don't bring it back.

If you really want to pursue this, find out if a circuit and or service manual is available. If there is not at least a circuit available then you will waste money and NO service done will be reliable. Do not break this rule or you will end up poor.

If there is a service manual or at least a circuit available then ask the shop if they will at least put in the full hours work for the minimum service charge you paid them. However be warned you usually don't accomplish much in an hour with a mess like this. A good tech could still not get the whole extent of the problem elucidated after six to eight hours work, and then you are on the line for $600 to $800 dollars and you still have the time to fix it and component costs.

Face it, this is just not a reasonable course of action.

In this day and age of compact boards and close spaced components, very few electronic components are worth servicing any more when they fail.

 

[mulhearn1022]

When I emailed polk they said the schematics and/or service manual was not available. But I just don't see how a system retailing at $2,800 could not have a service manual. I'll have to give them a call tomorrow when they're open and get them to give me the service manual or something of relevance.

 

[TLS Guy]

When I emailed polk they said the schematics and/or service manual was not available. But I just don't see how a system retailing at $2,800 could not have a service manual. I'll have to give them a call tomorrow when they're open and get them to give me the service manual or something of relevance.

It is not unusual in these money grubbing days, not to have circuits and service manuals published. A lot of gear, especially of the type you have was designed NEVER to be serviced.

Also remember Polk has been sold an bought at least once since that unit was made. If there were service documents available originally, typically they become NLA under new owners. To keep them takes to big a bite out of short term profits. This is one of the hall marks of "Crony Capitalism".

The original purchase price was outrageous. Polk must have been taking a leaf out of the Bose page book.

In future avoid all units of that type, especially Bose and all HTIBs like the plague.

Since you are a poor student cobble a system together from eBay and your local Craig's List. That will get you far further ahead.

 

[mulhearn1022]

What are some brands and models of receivers that I should be on the lookout for in my price range?

And if I do get a new receiver, would I be able to use the connects from the subwoofer driver to connect it to the new receiver? If that were possible, I'd just use the same enclosure I currently have with a slight modification.

 

[TLS Guy]

What are some brands and models of receivers that I should be on the lookout for in my price range?

And if I do get a new receiver, would I be able to use the connects from the subwoofer driver to connect it to the new receiver? If that were possible, I'd just use the same enclosure I currently have with a slight modification.

Forget trying to salvage your current sub. Take it to the recycling unit and end your relationship with it.

I can't answer your question precisely, unless I have a clear idea of how you want to use your system and what you want it to do.

I suspect at the minimum you need a 5.1 receiver with at least Dolby digital and DTS. You will need a powered sub. You can keep your current satellite speakers for the moment, but keep you eyes open for something much better.

I don't know if brand matters a lot. If it is older and still working fine, that tells you most of what you want to know.

Now when I said equipment is not serviceable, I should amplify that a bit.

Generally modern equipment is only serviceable by board change and that does not need circuits and a service manual as a rule.

The reasons are that modern boards use surface mount components, that can only be placed by robots and not humans. The law only requires boards be kept available for seven years after the last production.

Boards are made once and when gone they are gone. It frequently happens boards are gone before seven years. It is hard for a manufacturer to know how many boards to produce.

The next issue is the ICs to even make the boards. A lot of the ICs will be custom. Only one production run of almost all but the most popular ICs have only one production run, because of cost of set up. When gone they are gone. That is why older equipment with tubes and discrete transistors are so much easier to service.

I have had to give up in nice older units now and again or wait a long time for what I want to come up on eBay, because a custom IC has been NLA and usually for a long time.

You are not viewing the modern world of electronics from the correct window.

I would be 99% certain your unit is not serviceable by anyone. The reason being the boards are not serviceable due to type of construction and lack of service information and the boards being NLA a long time ago.

So this is my last piece of advice: - Move on!

 

[GranteedEV]

I recommend not bothering with multi-channel on your budget. try out a decent two-channel integrated amplifier. While it's nothing world class, here's something to start with:

Emotiva Audio | mini-X a-100 Stereo Flex Amp

 

[TLS Guy]

I recommend not bothering with multi-channel on your budget. try out a decent two-channel integrated amplifier. While it's nothing world class, here's something to start with:

Emotiva Audio | mini-X a-100 Stereo Flex Amp

It is not a desk top computer system. You can download the manual in a link in my first post.

It is a Bose type of knock off complete with a Bose full set of vices I would imagine..

I have asked the OP what his needs are however.

 

[mulhearn1022]

I will be needing a 5.1 channel amplifier and I will be using these satellites I have right now because I don't have the budget currently for new ones.

And you're right about the powered subwoofer. I would much prefer having a subwoofer hooked up to my home theater system rather than using my z-2300 as a seperate component, but I'm not opposed to that route either because of budget constraints. I suppose it would be possible to use the z-2300 sub hooked up to an amp through an analog multi-room output, since it can accept an RCA connection with the adapter I have.

 

[TLS Guy]

I will be needing a 5.1 channel amplifier and I will be using these satellites I have right now because I don't have the budget currently for new ones.

And you're right about the powered subwoofer. I would much prefer having a subwoofer hooked up to my home theater system rather than using my z-2300 as a seperate component, but I'm not opposed to that route either because of budget constraints. I suppose it would be possible to use the z-2300 sub hooked up to an amp through an analog multi-room output, since it can accept an RCA connection with the adapter I have.

I think you have already gone as far as you can with the Logitech system, by using the better quality satellite.

If this does not satisfy, then you need to put a good 2 channel system together with a sub. In general only multichannel receivers have bass management. This means that basically you need what I advised in my previous post.

One other word of advice. It will be much better to save for better gear and use what you now have in the meantime.

I was an impecunious student many years ago now. I learned in grade school to not bother with junk, but to be patient.

I still have units from my student days working well in my system now. It is now 50 years on. Now that's value.

If you do go with eBay and Craigslist then be very thrifty and spend no more than you can afford to use.

I have found eBay sellers not as honest as they were a few years ago.

A couple of weeks ago I bought a vintage Quad 34 preamp, that the seller said was working. It arrived and the electronic input selector board was down. The seller pretty much must have known this, and someone had been soldering on the board in a vain attempt to find a dry joint. I had to service the flip/flop switching board.

I made a formal complaint against the seller and made him reimburse me 1 hour of my service charges, which was $100. eBay came through and made him pay me for the service. I was impressed by that.

I pursued the matter to alert eBay to the fact that this sort of thing is not acceptable practice.

This would have turned out differently if I did not have the ability to service the unit, and the seller would have said it was damaged in transit and the unit was as is. However the seller stated that the unit was in perfect working condition. I objected to the fact that I had paid top dollar for a unit advertized as working perfectly.

So you have to be a bit careful and don't spend more than you can afford to loose. Unfortunately you are already $100 behind. I would go to that service shop and plead poverty and see if they will not give you some or all of that money back. However promise them that Polk unit will never set foot inside that shop again!

 

[BoredSysAdmin]

I think you have already gone as far as you can with the Logitech system, by using the better quality satellite.

If this does not satisfy, then you need to put a good 2 channel system together with a sub. In general only multichannel receivers have bass management. This means that basically you need what I advised in my previous post.

One other word of advice. It will be much better to save for better gear and use what you now have in the meantime.

I was an impecunious student many years ago now. I learned in grade school to not bother with junk, but to be patient.

I still have units from my student days working well in my system now. It is now 50 years on. Now that's value.

If you do go with eBay and Craigslist then be very thrifty and spend no more than you can afford to use.

I have found eBay sellers not as honest as they were a few years ago.

A couple of weeks ago I bought a vintage Quad 34 preamp, that the seller said was working. It arrived and the electronic input selector board was down. The seller pretty much must have known this, and someone had been soldering on the board in a vain attempt to find a dry joint. I had to service the flip/flop switching board.

I made a formal complaint against the seller and made him reimburse me 1 hour of my service charges, which was $100. eBay came through and made him pay me for the service. I was impressed by that.

I pursued the matter to alert eBay to the fact that this sort of thing is not acceptable practice.

This would have turned out differently if I did not have the ability to service the unit, and the seller would have said it was damaged in transit and the unit was as is. However the seller stated that the unit was in perfect working condition. I objected to the fact that I had paid top dollar for a unit advertized as working perfectly.

So you have to be a bit careful and don't spend more than you can afford to loose. Unfortunately you are already $100 behind. I would go to that service shop and plead poverty and see if they will not give you some or all of that money back. However promise them that Polk unit will never set foot inside that shop again!

Couldn't say it better myself...
TLS would say $200 is budget for junk and no where near possible to get a decent system even for a college ... and he's right... mostly

You could OK system, but you really need to start counting the pennies, looking for 2nd hard equipment and stop wasting $100 for such "repairs" - I agree with TLS - try to get the money back

I bet if you look hard enough you could find a solid used $100 5.1 AVR (without hdmi and other bells and whilles) and a $100 pair of Cerwin Vega speakers which would loud enough for parties

you polk system needs to be recycled.