Would the amplifier in a typical plasma tv be able to drive some external speakers, assuming the external speakers were sensitive enough?
I want to disconnect the internal speakers and connect the (same) wires to some external single driver speakers. (I'm guessing the internal amp is anywhere from a few watts to a few dozen watts?) The TV is at my in-laws; one of whom is technicallly challenged, the other has Alzheimer's. I've tried external amp from the line level out, but between the extra remote, and choosing the input on the external amp, etc., they're constantly confused and I just want to make something for them that sounds better (one has hearing problems too) but is seamless from their standpoint. I'd build a pair of bookshelf speakers with some high sensitivity full-range drivers.
Is this likely to work?
I could also feed that internal speaker output signal to a simple (Lepai-type, always on) amplifier and then onto the new speakers, but don't know if the input voltage to the Lepai would be too high, or if there are impedance issues I need to consider.
Thanks for any advice. Watching TV is one of just a few things that make my father-in-law happy.
I want to disconnect the internal speakers and connect the (same) wires to some external single driver speakers. (I'm guessing the internal amp is anywhere from a few watts to a few dozen watts?) The TV is at my in-laws; one of whom is technicallly challenged, the other has Alzheimer's. I've tried external amp from the line level out, but between the extra remote, and choosing the input on the external amp, etc., they're constantly confused and I just want to make something for them that sounds better (one has hearing problems too) but is seamless from their standpoint. I'd build a pair of bookshelf speakers with some high sensitivity full-range drivers.
Is this likely to work?
I could also feed that internal speaker output signal to a simple (Lepai-type, always on) amplifier and then onto the new speakers, but don't know if the input voltage to the Lepai would be too high, or if there are impedance issues I need to consider.
Thanks for any advice. Watching TV is one of just a few things that make my father-in-law happy.
Should be OK as long as the manufacturer has used a speaker with standard impedance. Some are quite high.
If you're considering using an external amp you're better off taking the signal from the RCA sockets, assuming the TV has them.
If you're considering using an external amp you're better off taking the signal from the RCA sockets, assuming the TV has them.
Yes. I modded my LG LED tv - disconnected internal speakers (4 of them, rated at 20W each ! but barely audible),
routed their cables to the back of the TV, and connected bookshelf JBL speakers (Northridge N24 model).
That was 1 year ago and they work just fine - clear and loud.
rayma - unfortunately we've tried headphones and they freak him out.
thx to haiqu and minek123 - I'm going to give it a try.
thx to haiqu and minek123 - I'm going to give it a try.
If the external speakers don't work out, have a single speaker right next to him on a long wire.
In some of those "flat screen" TV sets, the internal amplifier does NOT have a "common ground" associated with the speaker lines.
In that case, it is not wise to ever combine those (negative -) lines by connecting to an external amp that uses a common ground for the inputs.
Just a warning from someone that knows.
In that case, it is not wise to ever combine those (negative -) lines by connecting to an external amp that uses a common ground for the inputs.
Just a warning from someone that knows.
Agree.
Speakers may be wired to a "Hot" chassis (read as "Deadly") because they safely live inside a plastic cabinet, NWVER meant to be wired to the outside world.
Before anything else, check whether thatb TV has RCA audio out (best) or headphone out (which sadly mutes internal speakers), both will give you signal to drive a small amplifier or powered cabinet.
Your relative could have a small powered cabinet nearby, and adjust comfortable volume as needed.
More complex than what you expected, but covers all bases.
And using a prebuilt module and some suitable power supply, not much more complex.
Speakers may be wired to a "Hot" chassis (read as "Deadly") because they safely live inside a plastic cabinet, NWVER meant to be wired to the outside world.
Before anything else, check whether thatb TV has RCA audio out (best) or headphone out (which sadly mutes internal speakers), both will give you signal to drive a small amplifier or powered cabinet.
Your relative could have a small powered cabinet nearby, and adjust comfortable volume as needed.
More complex than what you expected, but covers all bases.
And using a prebuilt module and some suitable power supply, not much more complex.
Feed the signal from this into a line in on a separate amplifier. Advantage with this is that the TV remote still works
Brian
No, sorry, I think I have to put it right. I was wondering how a three pole phone jack would work with a BTL stereophonic amplifier, as per the previous posting.
Best regards!
Best regards!
Modern TVs are not hot-chassis (don't use valves or CRT!), they run at low voltages (except for plasma driver section if plasma rather than LCD). Any TV with sockets for HDMI/VGA/SCART or whatever on the back must be earthed chassis!
Are you sure? Our Philips TV only has a 2-pin plug so must be class 2 (double insulated)
Brian
Then it either has not exposed parts/sockets or a double-insulated PSU, otherwise it would be unsafe. If no exposed parts then
it would require further investigation for safety.
it would require further investigation for safety.
Let's let the OP enlighten us by posting the make and model number of the particular TV discussed.
Then, without speculation or endless meaningless guessing, I can perhaps locate a service manual - I've got access to them since I have serviced thousands of TV sets over the decades.
Panasonic Plasma TV model TH-C42HD18.
Sadly no headphone jack.
Service manual and Owner's manual linked below.
Service manual:
PANASONIC TH-C42HD18 SERVICE MANUAL Pdf Download.
Owner's manual:
Panasonic TH-C42HD18 user manual - ManualsBase.com - Solve your problem
Sadly no headphone jack.
Service manual and Owner's manual linked below.
Service manual:
PANASONIC TH-C42HD18 SERVICE MANUAL Pdf Download.
Owner's manual:
Panasonic TH-C42HD18 user manual - ManualsBase.com - Solve your problem
As I suspected, on page 48, the audio amp uses a floating speaker system, meaning neither speaker is at common ground. - the same basic design as my 2004 Panasonic Viera LED TV.
Notice, both + and - leads are not at ground potential, and if they were to be grounded together, it would destroy the amp chip.
The only safe way to derive audio from those outputs is to run "4" 1uf mylar caps to an external amp that uses a common ground system. (caps mounted on each speaker + / - lead)
This way any danger is eliminated.
Trust me, you don't want to have to get involved in replacing that audio amp chip!
Notice, both + and - leads are not at ground potential, and if they were to be grounded together, it would destroy the amp chip.
The only safe way to derive audio from those outputs is to run "4" 1uf mylar caps to an external amp that uses a common ground system. (caps mounted on each speaker + / - lead)
This way any danger is eliminated.
Trust me, you don't want to have to get involved in replacing that audio amp chip!
Yes, the on-board amp in the TV will work just fine.
As the "chip amps" are supplanting most all other amp types, they are being upgraded all the time, year after year.
Case in point, I'm always re-purposing amps all the time....what many years ago would be in TVs, PC outboard speakers, portable music boxes, etc...would be low power & low cost, AKA, the TDA 2822 amp chip....well, that seems to be changing, outright power is cheap, but the drivers inside our TVs & most all other speaker drivers are getting less & less efficient.
I dug up a pair of PC speakers, dusty, unused, unloved. I wanted to power a simple music system in our spare Bedroom, we had a "collectable"? pair of sixties era loudspeakers, the size & shape worked fine as a pair of nightstands.
Imagine my surprise as those old PC speakers were 12VDC outboard power & rated at Six watts of output power?...using the amp chip, the TDA1517P chip.
Now, the sixties were a time of "expensive power"...and those big old loudspeakers would just love to have Six watts to really sing. This setup will indeed drive you out of that bedroom just fine. It's the BIB, bigger is better philosophy. Pull apart that TV & go ahead & put some external speaker terminals to let the music come thru loud & clean.
--------------------------------------------------------------------Rick........
----------------------------------------------------------------------Rick......
As the "chip amps" are supplanting most all other amp types, they are being upgraded all the time, year after year.
Case in point, I'm always re-purposing amps all the time....what many years ago would be in TVs, PC outboard speakers, portable music boxes, etc...would be low power & low cost, AKA, the TDA 2822 amp chip....well, that seems to be changing, outright power is cheap, but the drivers inside our TVs & most all other speaker drivers are getting less & less efficient.
I dug up a pair of PC speakers, dusty, unused, unloved. I wanted to power a simple music system in our spare Bedroom, we had a "collectable"? pair of sixties era loudspeakers, the size & shape worked fine as a pair of nightstands.
Imagine my surprise as those old PC speakers were 12VDC outboard power & rated at Six watts of output power?...using the amp chip, the TDA1517P chip.
Now, the sixties were a time of "expensive power"...and those big old loudspeakers would just love to have Six watts to really sing. This setup will indeed drive you out of that bedroom just fine. It's the BIB, bigger is better philosophy. Pull apart that TV & go ahead & put some external speaker terminals to let the music come thru loud & clean.
--------------------------------------------------------------------Rick........
----------------------------------------------------------------------Rick......