Sony TV Audio Distortion

[teknoprep]

First let me say I am noobie and know very little about audio. Let me also say that I love your site, and look forward to learning much about the topic.

I have a problem. My 20 year old Sony Model#KV-2791R 27" television has recently began to have audio distortion problems. It happens when I turn the volume past the 50% mark (I am hard of hearing). It sounds like the bass distorts and loud noises are very hard to understand. A small rumble comes from the TV when this happens, so I am assuming it was the bass. I have went in the back and checked the RCA connection between my Dish Network receiver and the TV. When I take out the white cable, the problem decreases, but doesn't go away, leading me to believe the problem is located mostly in the left speaker. Also, when I switch to a coaxial cable, the problem stays there, telling me that the audio cables aren't at fault.

I was going to take it in for repair, but I wanted to see online what I could do myself. First, let me say I don't want to do the following:

1) Get external speakers (with a receiver) - I like the built in ones, and the fact that I don't have to have an extra remote just for the sound.

2) Get a new TV - my son wants me to get a new fangled HD Plasma 100" 7.1 Surround.....it goes on and on. This thing cost me $1000 20 years ago and its doing a pretty good job (despite the on/off button not working, but thats what remotes are for anyways).

I asked a friend if I could replace the speakers and he said I should be able to unscrew them and replace them with one's purchased online. I searched around but couldn't find any replacements - instead I found this place.

What do you guys believe the problem is? Also, if you recommend replacing the speakers, do you think I could do it himself, and if so, where could I purchase them, and how much would they cost?

Thanks again for your help - I look forward to learn a lot about this great hooby!

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UPDATE: I just called sony parts and they said the complete speakers where discontinued for this model. They did, however, sell just the tweeter, part #150348611, for $20.04 a piece. I'm not sure this would help (since I learned after some research that these are for high frequencies) and I assume theres no return policy.

 

[mtrycrafts]

First let me say I am noobie and know very little about audio. Let me also say that I love your site, and look forward to learning much about the topic.

I have a problem. My 20 year old Sony Model#KV-2791R 27" television has recently began to have audio distortion problems. It happens when I turn the volume past the 50% mark (I am hard of hearing). It sounds like the bass distorts and loud noises are very hard to understand. A small rumble comes from the TV when this happens, so I am assuming it was the bass. I have went in the back and checked the RCA connection between my Dish Network receiver and the TV. When I take out the white cable, the problem decreases, but doesn't go away, leading me to believe the problem is located mostly in the left speaker. Also, when I switch to a coaxial cable, the problem stays there, telling me that the audio cables aren't at fault.

I was going to take it in for repair, but I wanted to see online what I could do myself. First, let me say I don't want to do the following:

1) Get external speakers (with a receiver) - I like the built in ones, and the fact that I don't have to have an extra remote just for the sound.

2) Get a new TV - my son wants me to get a new fangled HD Plasma 100" 7.1 Surround.....it goes on and on. This thing cost me $1000 20 years ago and its doing a pretty good job (despite the on/off button not working, but thats what remotes are for anyways).

I asked a friend if I could replace the speakers and he said I should be able to unscrew them and replace them with one's purchased online. I searched around but couldn't find any replacements - instead I found this place.

What do you guys believe the problem is? Also, if you recommend replacing the speakers, do you think I could do it himself, and if so, where could I purchase them, and how much would they cost?

Thanks again for your help - I look forward to learn a lot about this great hooby!

--------------

UPDATE: I just called sony parts and they said the complete speakers where discontinued for this model. They did, however, sell just the tweeter, part #150348611, for $20.04 a piece. I'm not sure this would help (since I learned after some research that these are for high frequencies) and I assume theres no return policy.

Will this Sony allow you to hook external speakers directly to the TV? Some models do this, XBR for one.

It sounds like your low frequency driver may be suffering old age rot; 20 years is a long time for those speakers.
You either solve the speaker issue with an external one, see if you can learn about the internals speakers to replace them with comparable size and shape ones, or get a new TV. After 20 Years, maybe it is time to upgrade to HDTV

 

[teknoprep]

Lfd

Will this Sony allow you to hook external speakers directly to the TV? Some models do this, XBR for one.

It sounds like your low frequency driver may be suffering old age rot; 20 years is a long time for those speakers.
You either solve the speaker issue with an external one, see if you can learn about the internals speakers to replace them with comparable size and shape ones, or get a new TV. After 20 Years, maybe it is time to upgrade to HDTV

Thanks for the quick reply!

I don't believe I can hook external speakers up direclty to the TV. I could always buy external speakers, but then I would have to get a receiver (correct me if I'm wrong) to convert from the speaker wire to RCA, and change the volume with another remote.

Another person also told me that I could get internal speakers as long as they were the same shape and size - but I have no idea where to look for them (I've been searching Google forever).

I know, everyone is telling me you have to upgrade to HD, especially with my son getting an XBOX 360. But you would be amazed at the quality of this TV. Besides the size, you couldn't tell it was 20 years old. Plus I'm probably going to wait until the LCD 40 inchers get a little cheaper before I splurge and buy one...in the mean time I hope these speakers are cheap enough to replace on their own (crossing my fingers at under $100).

What is the low frequency driver, btw? Is it in the speaker or is it in the TV? I am kind of trying to figure out where the problem is, because I'm wondering why both speakers went bad (the left worse than the right) at the same time. Also, any links and prices to sites that sell these speakers would be great.

Thanks again!

 

[mulester7]

.....Technoprep, I run the TV cable signal to an S-VHS VCR, and use the TV as a monitor only, tuned to ch 3....I send the left and right stereo signals of the TV audio from the VCR to a pre-amp, and my TV sound makes people just sit and stare at the whole system....I think you can do the same with a satellite system, I wish someone would comment....you can also put a Games-Box three-way-rca, on the front panel of the S-VHS model I have....with any VCR, especially an S-VHS, if it is new, it can sharpen and color-up a cable signal when you kick in "it's" tuner section....and lastly, the S-VHS deck, is coupled to the TV by an 8 or 9 post din-jack....am I kidding myself?....is this old-timey?.....

.....edit....and as far as I'm concerned, there is no one better at building S-VHS VCR's than JVC....and we'll have strong words over that one....

 

[mtrycrafts]

Thanks for the quick reply!

I don't believe I can hook external speakers up direclty to the TV. I could always buy external speakers, but then I would have to get a receiver (correct me if I'm wrong) to convert from the speaker wire to RCA, and change the volume with another remote.

Another person also told me that I could get internal speakers as long as they were the same shape and size - but I have no idea where to look for them (I've been searching Google forever).

I know, everyone is telling me you have to upgrade to HD, especially with my son getting an XBOX 360. But you would be amazed at the quality of this TV. Besides the size, you couldn't tell it was 20 years old. Plus I'm probably going to wait until the LCD 40 inchers get a little cheaper before I splurge and buy one...in the mean time I hope these speakers are cheap enough to replace on their own (crossing my fingers at under $100).

What is the low frequency driver, btw? Is it in the speaker or is it in the TV? I am kind of trying to figure out where the problem is, because I'm wondering why both speakers went bad (the left worse than the right) at the same time. Also, any links and prices to sites that sell these speakers would be great.

Thanks again!

Most likely you may have two small speakers on each side but not sure. If you do, the low frequency driver is for the lower frequencies and the tweeter is for the upper ones.
I had an older XBR that had speakers separate from the TV case, externally mounted and that had speaker wires from the TV going directly to the speakers. When they went, like what yours sounds like, I was able to connect external speakers directly But then the TV died as well not long afterwards.

So, if you cannot hook one up directly, then the only option is replacing the internal speakers or adding an amp or receiver with speakers from them.

If you pull the TV case, or somehow look inside and see how many actual speakers you have inside, perhaps a part number, maybe even Sony might have replacements. If not, the internal speakers would have written how many ohms it is and you can measure the diameter, then maybe even Radio Shack may have that size speaker. After all, as long as it works, you will benefit.

 

[teknoprep]

Most likely you may have two small speakers on each side but not sure. If you do, the low frequency driver is for the lower frequencies and the tweeter is for the upper ones.
I had an older XBR that had speakers separate from the TV case, externally mounted and that had speaker wires from the TV going directly to the speakers. When they went, like what yours sounds like, I was able to connect external speakers directly But then the TV died as well not long afterwards.

So, if you cannot hook one up directly, then the only option is replacing the internal speakers or adding an amp or receiver with speakers from them.

If you pull the TV case, or somehow look inside and see how many actual speakers you have inside, perhaps a part number, maybe even Sony might have replacements. If not, the internal speakers would have written how many ohms it is and you can measure the diameter, then maybe even Radio Shack may have that size speaker. After all, as long as it works, you will benefit.

It does look like 2 big (internally) removable speakers, kind of like this:

http://servicesales.sel.sony.com/web/viewItemDetail.do?operation=getItemDetail&itemID=596126&category=4&categoryName=Home Audio

Sony said they still made the tweeter, but thats it. I'm going to listen closer to the audio tommorow to see if its the low frequencies or high frenquencies. If this is the problem, will I have to replace the entire speaker, or just a part (do they solder on)? Also, are those components inside each speaker, or inside the TV unit (I am curious why both went out at the same time, one slightly worse than the other)?

I guess I am going to remove the speakers tommorow and look for the information you told me, call Sony and go to Radioshack. Hopefully they don't cost $250...we'll have to see...I'll give you an update tommorow.

Thanks!

 

[mtrycrafts]

It does look like 2 big (internally) removable speakers, kind of like this:

http://servicesales.sel.sony.com/web/viewItemDetail.do?operation=getItemDetail&itemID=596126&category=4&categoryName=Home Audio

Sony said they still made the tweeter, but thats it. I'm going to listen closer to the audio tommorow to see if its the low frequencies or high frenquencies. If this is the problem, will I have to replace the entire speaker, or just a part (do they solder on)? Also, are those components inside each speaker, or inside the TV unit (I am curious why both went out at the same time, one slightly worse than the other)?

I guess I am going to remove the speakers tommorow and look for the information you told me, call Sony and go to Radioshack. Hopefully they don't cost $250...we'll have to see...I'll give you an update tommorow.

Thanks!

Most likely they went pout because the surround material attached to the cone is deteriorated equally with time.
I would not suggest buying new Sony speakers as per your link. You should find something for much less that will serve your TV watching needs. You could run speaker wires, if you end up buying external speakers, from the speakers to where the old one is connected.

I have no idea how your TV has the speakers constructed and mounted. Just be careful about opening the TV unless you can just gain access to the speakers alone excluding access into the TV. I cannot recommend that as there are high voltage caps even when unplugged, they can give a good jolt.

 

[teknoprep]

Operation

Well, I took her apart. Boy does a lot of dust accumulate in those things after 20 years!

I saw 2 speakers and 2 parts to each speaker - the LFD and the tweeter. Two cables were running out from each and all 4 combined to one cable to run into the main board. The part numbers were as follows:

Tweeter - 1-503-486-11 ($20.04 from Sony)
LFD - 1-503-538-11 (Discontinued from Sony)

I tested out the sound again, and sure enough it was the low frequencies - just my luck! Since the wires were soldered in the LFD, I probably couldn't have replaced them anyways.

I decided to (carefully, as not to get shocked) remove the left speaker's wire from the motherboard's connector. After turning on the TV, the right speaker still made the rumble, but not as bad. So I'm guessing both speakers have the problem, but the left one is worse.

As a temporary solution, I've disconnected the white RCA cable so only the right speaker works. I know this would probably freak out all you audiophiles, me only having mono sound, but my old ears can't tell the difference

I have some external Bose speakers from a radio, but they have speaker wire instead of the RCA jacks. I assume I have to purchase an AV receiver to get these to work, but the cheapest one's I could find were $200. They all were for surround sound systems. I'll be looking at my local pawn shop tommorow for some cheap ones. Does anyone know of any that are cheap and just run 2 speakers, or a device that's similar that does the same job?

Thanks!

 

[mtrycrafts]

Well, I took her apart. Boy does a lot of dust accumulate in those things after 20 years!

I saw 2 speakers and 2 parts to each speaker - the LFD and the tweeter. Two cables were running out from each and all 4 combined to one cable to run into the main board. The part numbers were as follows:

Tweeter - 1-503-486-11 ($20.04 from Sony)
LFD - 1-503-538-11 (Discontinued from Sony)

I tested out the sound again, and sure enough it was the low frequencies - just my luck! Since the wires were soldered in the LFD, I probably couldn't have replaced them anyways.

I decided to (carefully, as not to get shocked) remove the left speaker's wire from the motherboard's connector. After turning on the TV, the right speaker still made the rumble, but not as bad. So I'm guessing both speakers have the problem, but the left one is worse.

As a temporary solution, I've disconnected the white RCA cable so only the right speaker works. I know this would probably freak out all you audiophiles, me only having mono sound, but my old ears can't tell the difference

I have some external Bose speakers from a radio, but they have speaker wire instead of the RCA jacks. I assume I have to purchase an AV receiver to get these to work, but the cheapest one's I could find were $200. They all were for surround sound systems. I'll be looking at my local pawn shop tommorow for some cheap ones. Does anyone know of any that are cheap and just run 2 speakers, or a device that's similar that does the same job?

Thanks!

Since you went to all this trouble and now have a better idea what is going on in there, you may just want to replace the low driver and if you find one that will fit, might as well do the tweeter for that $40 for the pair.

Does that LHdriver have an ohm rating on it? Also, buy a soldering iron and unsolder the wires. It is easy to do. You may want to take that LF driver to Radio Shack and see if they can match it. Problem solved. Or, there may be an on line replacement speaker place?

Can you see physical damage to the cone area on that LF driver? I bet there will be like I figured it would be it.
Great job of troubleshooting so far.

 

[teknoprep]

Since you went to all this trouble and now have a better idea what is going on in there, you may just want to replace the low driver and if you find one that will fit, might as well do the tweeter for that $40 for the pair.

Does that LHdriver have an ohm rating on it? Also, buy a soldering iron and unsolder the wires. It is easy to do. You may want to take that LF driver to Radio Shack and see if they can match it. Problem solved. Or, there may be an on line replacement speaker place?

Can you see physical damage to the cone area on that LF driver? I bet there will be like I figured it would be it.
Great job of troubleshooting so far.

Thanks for the encouragment!

I put the cover back on to watch some TV - its easy to take off but a pain to put back on, heh, but I remember seeing an OHM symbol on the unit, kind of like this:

http://home.flash.net/~ohmmusic/ohmwebhead.jpg

So I assume it had a number next to it. I also really didn't see damage (there could be but my virgin eyes aren't seeing it), except for a lot of dust...the wires looked intact.

I have a soldering iron, but the unit is pretty deep in the TV and has plywood around it (yep...this TV is so old the case wasn't made 100% of plastic). I see some screws, but I'm not sure if I can unscrew the LDF & tweeter then then unsolder them...I assume I can, but I'll have to look more in depth, or take some pictures and post them. I might even pay someone to do it, because if I screw this up, I'll have to spend the money on an AV receiver anyways.

I'll open her back up tommorow and see if I can take out the LDF, then take it to Radioshack for analysis. I'll report back then.

Thanks as always!

 

[teknoprep]

Fixed!!

I know this is going to drive all you audiophiles crazy, but I fixed my TV! You wanna know how? Hints...it didn't cost a penny, nor did it require opening up the TV.

Answer: I turned the Bass knob on the front panel of the TV to the 1/4 position (from 1/2). I know, I know...most of you guys think bass is the best part (or is that teenage kids), but this fixed the problem 100%. When I turn the sound up, no more rumbling or audio distortion, and it didn't require getting shocked or forkin' out the big bucks for new equipment- heh.

This should probably let this TV live a couple more years until the LFD corrodes so worse that it won't even work. Hopefully by then digital and high def TV will be in full view, and the good quality LCD TV's, Surround Sound systems, and Dish Network receiver's will be a little cheaper. Believe me, I'll be back then to get your advice on the "latest and greatest" surround sound system! I'm amased at how long this thing lasted with no repair. I love how Best Buy tries to sell you 4 year extended warranties - my reply is, "Shouldn't it last that long without repair WITHOUT the warranty?" - I guess they don't make 'em like they used to.

Finally, I would like to again say 'Thank You' for all your support! Those fast responses were great, and I actually learned a thing or two about speakers. I hope to continue learning in the future about this great hobby!

 

[mtrycrafts]

Answer: I turned the Bass knob on the front panel of the TV to the 1/4 position (from 1/2). I know, I know...most of you guys think bass is the best part (or is that teenage kids), but this fixed the problem 100%. When I turn the sound up, no more rumbling or audio distortion, and it didn't require getting shocked or forkin' out the big bucks for new equipment- heh.
!

That's great Now you have experience at troubleshooting those speakers
With the bass setting up so much, either they were over driven or the internal amp was over driven.
I'll try to remember this for the next time.