Our TV power supply transistors finally gave up the ghost and so we purchased a new "smart" Vizio D40f-JO9 TV but we've been appalled at the very low quality of the audio. Voices sound like they're talking through a pillow and sound very muffled. After trying to improve the sound by adjusting the audio software I decided to connect a pair of outboard speakers. That's when I learned that there aren't any output ports for external speakers and that the new convention is to go 'wireless' with Bluetooth technology.

Some comments I've read say that we can run an HDMI cable to a stereo tuner/amplifier but others say this creates a delay between the audio and the video so characters voices don't match their lips onscreen.

Other comments recommend that amplified speakers with Bluetooth technology is the best way to get some sound from our set. Before I invest $80 - $110 on a 'sound bar' or amplified speaker, I'd like to get some advice from those who can offer me some guidance on this issue. If anyone has solved a similar problem, I'd sure like to hear from them, perhaps with a specific product / model number.

I have several pairs of external speakers but they're old technology and I have no clue how they might be connected to my new smart TV. (???)

 

The TV spec says it has a Analog Stereo Output (3.5 mm) so all you need is a Plain-Jane Stereo amplifier to drive existing speakers from it.

Analog Audio Out — Select Variable if you are controlling the volume with the
remote. Select Fixed if an external audio device (sound bar or AV receiver) will
control the volume.

 

Do have an external amplifier, or just speakers?

 

A friend had the same problem. I made an amplifier using this module from AliExpress: It's powered by 5V from the TV USB port. The input is a stereo cable with a 3.5mm connector that plugs into the TV headphone output. I used RCA connectors for the output to two decent bookshelf speakers. It has a volume control and gives more than enough volume for normal viewing. The plastic box I put it in cost more than the amplifier module!

 

There are two external outputs for audio , 3.5mm stereo headphones and a spdif fibre optic, usually when the headphone socket is used the internal speakers are shut off, or there is an option in the audio settings for a separate volume control.

According to the manual if using a soundbar the internal speakers are automatically shut down and there's a lip sync adjustment in the settings.

 

Thanks, folks! I believe I've got it now. This is the lousiest sound that I've ever encountered on any TV and it's something that we really just don't want to live with. I was of the impression that the onscreen setup was all the information available and so it's good to know that there IS an owner's manual online. Nothing in the box mentioned it.

It's also good to know that there IS an audio output jack that I can use to connect an external speaker. I was laying awake last night trying to devise a way to use an amplified speaker and switch it on/off with the TV power. I really like the 5 V amplifier idea for that reason alone! That'll most likely be my next little project around here while in the meantime there are a number of speakers out in the shop for us to use in a pinch. Tomorrow, I'm off to the thrift stores to find a plug/cable. (Radio Shack is gone.)
I love it when a plan comes together! You'uns are the GREATEST! I appreciate you!
Dax

 

Let us know how it works out.

 

The little PAM8403 amplifier IC produces 3W per channel into 4 ohm speakers with severe distortion or 1.2W into 8 ohms or 1.8W into 4 ohms with low distortion. That is enough power if you sit near the speakers.

 

devise a way to use an amplified speaker and switch it on/off with the TV power. I really like the 5 V amplifier idea for that reason alone!

They do sell outlet strips you plug the TV into, and they turn other outlets on when the TV is drawing power, and off when its not (example).

As AGA noted, amps using the limited power 5V output may not generate sufficient volume, especially for the bass frequencies.

 

If you need inexpensive quality audio this is one place to shop: https://www.parts-express.com/home-.../home-audio-amplifiers?base_price=0.00to76.22

 

The little PAM8403 amplifier IC produces 3W per channel into 4 ohm speakers with severe distortion or 1.2W into 8 ohms or 1.8W into 4 ohms with low distortion. That is enough power if you sit near the speakers.

In actual fact, it produces very clear sound with no noticeable distortion using two 8 Ohm speakers. That is 1.2W on each channel which is far more than enough volume when using reasonably good speakers. My friend is very happy with the results.

 

I just bought a Sony with a similar problem, the mid range-Human-Speech was a little muffled for the elderly us, I picked up a Bose Under-TV speaker that has a mid-range enhancement option, also works with Blue-Tooth.

 

TV speakers are always terrible, flat panels even more so. You can get high quality two-channel or decent surround sound from the optical output, or by using ARC through an HDMI connection to an AV receiver. My choice would be the best used AV receiver you can find for a reasonable price. If it doesn't support HDMI audio with at least TrueHD and DTS-MA, it's obsolete, but it'll be good enough for most TV and streaming content. AV receivers can be configured for whatever number of speakers you can manage to hook up, though I'd say 2.0 is the bare minimum unless you only watch old movies and TV in original mono.

 

It's probably overkill for this application but I have a Denon receiver in a 5.1 configuration (bought a "refurbished" one for about $100 less than a new one, but it looked brand new when it arrived).

The side surround speakers usually don't do much, but I like the center speaker along with the left and right front speakers, since I can turn up the volume of the center relative to the sides, which reduces the relative ambient crowd noise that often comes over the side speakers in some sports broadcasts which is so loud it makes it difficult to understand the announcers from the center speaker.

It also has a good subwoofer, which is nice for action or Sci Fi movies which often have significant low frequency sound effects and rumble below 100Hz, which you can't really hear at all with standard TV speakers.
Even hearing the low frequency ambient sounds at a football game, such as the band bass drum, or the Buccaneers' cannon firing, make you feel more like you are at the game.

I run the HDMI signal from my Fire TV Streaming Stick through the receiver to pick up the full uncompressed 5.1 sound signal, which the Toslink optical signal can not carry.
The receiver also has an adjustment for sound delay to sync it with the picture.

 

For a stereo amp, I'd use something that runs on 12V, which will give you a healthy 10 to 15 watts, which happens to be the same as a "high power" car head unit. There are ready to use amp modules on ebay etc for under $10. I've used TA2024 (Tripath, which are long out of production so new amps may have counterfeit chips), but also obtained YDA138 and YDA148 modules (based on Yamaha chips), but haven't used them yet. For power, I've used 12V Wii power supply from a thrift store, but there's usually a bunch of 12V bricks at thrift stores if you don't have one lying around. If you want the least sketchy TA2024 amp boards (or a complete one in a box), check out Sure Electronics. I got one of their boards to start with, and it came complete with binding posts, power and audio cables, so when there was a power failure one winter night I took it out of the envelope and had it playing music in minutes with no soldering.

 

Tripath says 15W but the graph shows clipping begins at 5.6W for 8 ohm speakers or 9.5W for 4 ohm speakers.
My car speakers produce higher power since the battery is charging at 14.4V and the speakers are much closer to me than my TV is. You probably need more power for the TV sound system.

 

Tripath says 15W but the graph shows clipping begins at 5.6W for 8 ohm speakers or 9.5W for 4 ohm speakers.
My car speakers produce higher power since the battery is charging at 14.4V and the speakers are much closer to me than my TV is. You probably need more power for the TV sound system.

Have you really listened to 5.6 Watts of stereo using a pair of decent 8"+ infinite baffle speakers with tweeters (not an inefficient TV soundbar using 2.5" toys)? In a domestic environment, it is enough to blow you out of your seat. Even 1 Watt can be uncomfortably loud!

 

I have never had a stereo that produces only 5.6 real Watts per channel.

 

You can read reviews like this from back when audiophiles discovered that cheap class-D can sound rather good.
https://www.stereophile.com/solidpoweramps/1006sonic/index.html

In a large room with background noise you may need more power, but since loudness isn't a linear relationship to power, you'll need ten times as much power to sound twice as loud.

 

Tripath Technologies went bankrupt 17 years ago. The similar TPA3116 but higher power (with a higher power supply voltage) class-D amplifier from Texas Instruments has replaced the Tripath amplifier IC.