Amplifier IC used in the computer speakers plus a mod

[@DrCassette]

Back in the 2000s when these amplified computer speakers could be found absolutely everywhere, I used to get quite a few at flea markets just to experiment with them. The best ones I found actually used two TDA2030A chips.

[@jstro-hobbytech]

I got a set of klipsch 5.1 for my pc as a young fella and the preamp kept blowing and I lost them in a couple moves on my 20s. They sounded much better than normal pc speakers I paid 800 for the set. They stopped selling them because you could just do a small mod on the sub and hook them to any receiver. I wasn't a deep into electronics then as I am now. I'm getting ready to build an amplifier for my record player and hopefully come across a nice pair of second hand speakers from the 89s and 90s. None of my home theater systems due records justice. Porcupine Tree have some blurays mastered for 5.1 snd they sound amazing with all the layering coming in from different directions. It really does their dense, virtuous prog rock justice. I use nearfield studio monitors in my workshop for recording guitar and bass but I want to diy a stereo listening area. Sorry for rambling. I Nerd out easily.

[@terencekaye9948]

All your videos are Great John...

[@danieldrz251]

For you who like IC amplifiers, I suggest you try the sta540san. I built one at 14volts 4 ohms and double bridge for my PC and it was exlente, very musical.

[@OIE82]

ST says it's obsolete. Digikey and Mouser don't have any stock so...

[@gkdresden]

It is a really very old circuit design and manufacturing technology. I was impressed to find something like this in a product which is currently selled.

[@1pcfred]

It's definitely old stock from somewhere. John should have looked for a date code on that IC. I bet those speakers are more than 10 years old. It just looked old the board and parts.

[@JohnAudioTech]

@@1pcfred Probably more like 20 years given the ivory color.

[@1pcfred]

@@JohnAudioTech could be. It has a vintage look to it. You just don't see those chicklet capacitors in stuff anymore. Or the phenolic circuit board. I bet it's real lead solder even. Those flux fumes can take you back.

[@johncoops6897]

@@1pcfred - ROFL, you _almost_ wrote "those lead fumes" didn't you?

[@keithblume5159]

I would have been pleasantly surprised to see all those discrete components inside. I also would have felt compelled to mod it just like you!

[@creepingmee]

Like! Please continue to make shorts like this, interesting.

[@twotone3070]

I recently repaired a friends music keyboard which used a ta8227 and this had failed. I don't know why it failed, but the minimal, paper thin piece of bent aluminium masquerading as a heatsink was barely touching the chip. I replaced the chip and added some 1/16" thick aluminium to the bent aluminium with self tappers that must have at least trebled it's capacity, working on the basis it wouldn't do any harm. We shall see.

[@waterbuoy1262]

had the 'recessed screw problem' repairing motor air compressor. Was a torx screw bit. Ripped the plastic off! nobody wants repairs done to their products now days, but I got at the compressor and resealed rings. tks the other led diagnostic vid excellent run down of parts board and failure of led.

[@russellhltn1396]

I like the short format. I like the information of the long format, but finding time to watch them can be an issue.

[@worstuserever]

I'd like more of this type, if it fits with your schedule and if there's also some satisfaction in it for you. Cheap products can provide a reasonable base for quick and simple modification. I just dismantled a computer speaker set that has no serious faults but an ugly housing. The power switch is broken and pots probably just need a clean, that's all, then I'll build a nice little wooden enclosure and give it away.

[@richardbrobeck2384]

nice I love those computer speakers I have a older pair of Harmon Kardon ones that very similar . speakers like that are very useful and you can get them fairly cheap.

[@kernalkorn1514]

Short videos are alright too! They can be about more specific topics.

[@TheDrunkenMug]

Hey John, great video and record player demo :D Thanks, stay well. From Holland

[@kokodin5895]

i once got speakers to fix that just used some 2A switching transistors a whole 3 of them, in paralell mono those were sooooo well made i couldn't bring myself to screw them back

[@fiercefeline5096]

The washing machine provides sympathetic vibration and resonance that vastly improves the sound of Crosley type record mutilators, when playing Motörhead lps.

[@strugglingparodox5709]

I certainly was expecting a tea2025b chip. Back when all you could find at second hand stores fo a while, was computer speakers. Thats how i ended up with a small hoard of boards. And, how i sent you those chips.

[@quananginh9446]

It is less than 1W into low-sensitivity speaker drivers, but still pretty loud :D

[@era7928]

Whoa, i was thinking to redo a review as video on how my 20 year old tda2822 based cheap pc speaker could drive a left passive of active speaker while improving their sound quality with bigger coupling caps. Albeit at lower volume. Could have shown people that sound quality is all about the loudspeaker brand and amp problem is already solved by cheap class D component.

[@sixtyinsix]

Any other cheap mods for improving those speakers? Polyfill/batting in the original enclosures? Splurge on real wood enclosures made from free pallets?

[@Friendroid]

I still have 3 pairs of this kind of speakers and recently brought them out again. One pair sounded too shrill and I was able to improve the sound overall using polyfill.

[@xaenon]

The 'real wood' enclosures combined with larger drivers isn't a bad way to go, though I would pick 8-ohm drivers so as to not push the amp chip too hard. I transplanted a similar amp into some older thrift-store speakers. There is more bass and they don't do too awfully bad. A bit big to be 'computer' speakers (unless you have a really big desk!). Makes a nice 'shop' setup, though.

[@amitghosh6966]

Very nice video

[@andymouse]

This sort of stuff is fun !......cheers.

[@alphabeets]

I hope that tape holds. If it doesn’t, it could short something if it flops around inside.

[@jutukka]

True. And it can cause a damage worth $3.55. Of course, if it shorts in a big way and burns your house as well, damage can be much bigger.🤔

[@JohnAudioTech]

The tape is pretty good. I haven't had problems of things coming detached if the specifications are followed.

[@jutukka]

@@JohnAudioTech If you say so, I believe you. But after many year's bad experiences of many types of tapes, IMHO the definition of tape is: Stuff that sticks to everything it shouldn’t, but does not stick reliably to any surface it should stick to. 😀

[@41intelectual]

Hey John, just stumbled on your channel. Already subbed! Curious about those speaker kits from parts express. Have you done any reviews on them? Like the C-note or Overnight Sensations.

[@JohnAudioTech]

Thanks for watching! I have not tried these kits. I'm happy with the speakers I have now. I don't review speakers very often. There are some other channels that do nice speaker reviews.

[@イエンスヨハンセン]

Love your work as always. I reckon you could improve these speakers vastly more by sticking them in a better enclosure. This amorphous plastic rubbish is never ever good. Even a simple ported enclosure would make for a much better tonal balance

[@1pcfred]

For a few bucks those speakers are loss leaders. A better enclosure might help them out but they're pretty decent as is for what they are. I took apart some PC speakers I had lying around and made a center channel speaker out of them for my PC. Just the drivers. They're Altec Lancings.

[@gehanameresekere1345]

The enclosures are the problem. Even having these drivers in open baffle configuration should be a big improvement. Or you could connect the outputs from the board to your large speakers and test for distortion and power output. In my opinion these will do 60% of the quality of a large 35 amplifier. Please try this and see ... connect the ouput wires to large speakers and make a video.

[@johncoops6897]

In Australia we have a saying that advises that "You cannot polish a turd".

[@1pcfred]

@@johncoops6897 Mythbusters tested that and found that you actually can polish a turd. The real question remains do you really want to though. Because polishing turds is as nasty work as it sounds. Some turds do polish better than others do too. They went to a zoo and got all kinds of different scat. You really don't want to polish lion crap from what I hear. It has a pungent bouquet.

[@イエンスヨハンセン]

@@johncoops6897 haha, yeah we have that in the UK too. This might not a turd though -- only way to find out is to stick them in a proper enclosure.

[@Gabson9]

These kinda speakers sounded so good for their price. Now you have to pay 50euros for entry-level 2.0 that sound a lot worse.

[@twotone3070]

That Philco sounded like it has baked bean cans instead of speakers, well I suppose they'd be cheaper.

[@1pcfred]

I thought the video was entertaining. I really wanted to hear that one track and you played it.

[@larryshaver3568]

that cartridge doesn't sound bad

[@pedrosantana3283]

For some reason I can't find an english version of the amplifier datasheet. All of them are in japanese. Pain

[@forsale313]

Great video.

[@XtremeKremaTor]

Caps would benefit from being on the stand offs and away from the heat

[@johnsonlam]

For a portable record player, it's not too bad.

[@johncoops6897]

You are kidding, right? Not too bad compared to... scraping a garden stick around the grooves?

[@larryshaver3568]

where do you get that tape ? that sounds good

[@JohnAudioTech]

Digikey. Check the datasheets to select the best tape for your needs.

[@jp040759]

Heavy Duty are all carbon zinc batteries. Don't support Goodwill. Great video. Happy Thanksgiving

[@ergindemir7366]

According to datasheet 9V@4Ohm is fine. Would it be better if the heatsink was made of copper and soldered to the ground pins?

[@JohnAudioTech]

Yes. The center ground pins are designed to remove heat from the chip. The way I did it isn't ideal, but will remove enough heat to keep the die temp down.

[@johncoops6897]

I've made quite a few headphone amps from this style of chip, and I've always just soldered copper flag heatsinks to the ground pins as-per datasheets. I found one amp recently that is about 35 years old and my heatsink flags were made from an old baked beans tin can !!

[@ergindemir7366]

@@johncoops6897 Cool, you can actually get a decent cooler for a penny, which is a penny. I use Russian dimes which are even cheaper.

[@amitghosh6966]

Can we use the same type of heatsink with tea2025 using this thermal tape ?

[@JohnAudioTech]

It would help but heatsinking off the center pins would be ideal.

[@johncoops6897]

These kind of chips are designed with internal heatsink that conducts out via the centre pins (either 2 or 3 on each side). After soldering the chip into the PCB you then solder two flat sheets of copper or tin-plated steel onto the outsides of the ground pins in the middle of the chip. You may find old datasheets to find the specs of heatsink surface area, but the bigger the better. I shape and angle them like little butterfly wings.

[@JohnAudioTech]

@@johncoops6897 Yep, the old Starver V-7 heatsinks

[@xaenon]

Unless it is specifically labeled as an 'alkaline' battery, you can safely assume it's not alkaline. The term 'heavy duty' is used for zinc-carbon type batteries because 'heavy duty' is essentially a meaningless but impressive-sounding term that marketing types love to throw around.

[@keithblume5159]

I had recently read that "super heavy duty" refers to Carbon Zinc. I put them in my maglight Because they are so light. They work awful though

[@JohnAudioTech]

Back in the 1980s and before there were often three types of primary cells available in the common sizes (AA, C, D, ect.) With the cheap carbon zinc cells, Eveready brand sold with a primarily silver label, Radio Shack used red. The next step up was the so called "heavy duty" cells, primarily in black by Eveready and green by RS. I think these were a zinc chloride chemistry. They were touted as having double the life of the carbon zinc cells. Alkaline was the premium cell and Eveready used the "Energizer" brand and RS used a gold label. At some point (1990's?) the true "heavy duty" zinc chloride cells were no longer produced and the marketing champs put "heavy duty" on the carbon zinc cells.

[@keithblume5159]

@@JohnAudioTech I was thinking of the "Super" designation. I have Energizer Alkaline that say Heavy Duty. But it seems the "Super" is reserved only for the Worst of all!

[@dmcbohol]

and where's the little snicky sneaker cat? 8-)

[@thomasr.5443]

Darn it John, where the heck did you get these cool speakers for just around three bucks? 😱 eBay?

[@TheTrueVoiceOfReason]

Clearance section at Parts Express. Shown a couple of videos back.

[@thomasr.5443]

@@TheTrueVoiceOfReason thanks!

[@jstro-hobbytech]

You should've got the liquid metal out instead of thermal tape haha

[@brianbenson5769]

If you can find them, the TDA 2005'S are far better. And they are class B amps, too.

[@kermets]

I like any videos.....

[@ats89117]

How would you get cancer from a screwdriver?

[@22hilding]

The only thing I got from screwdrivers was a hung over...;-)

[@xaenon]

Supposedly from the materials is made of; the plastic handle and the chrome plating. The risk is actually quite small, but there's a push to plaster warning labels on anything that might even be SLIGHTLY dangerous. You can thank lawyers and insurance companies for this.

[@ats89117]

@@xaenon I think the risk might be that if you swallowed the screwdriver, you might develop cancer years later. But if you swallowed one of those screwdrivers, you would have much more serious issues to deal with!

[@1pcfred]

Crush up the handles and smoke them in a crack pipe is my guess.

[@listerine-pr5lt]

So called Cheap Pc Speakers sound more expensive than they look.

[@AnthonyPrechtl]

Definite like

[@fredfabris7187]

Oh my gosh the record is horrible!😂

[@KuntalGhosh]

This is why i don't buy computer speakers. All of them are real over priced crap. I made my own speakers with a pair of sony car speakers and mdf box made by a guy who specialises in speaker cabinets and i use a tda7498 class d amp board to run them at enough power to vibrate my room 😂 although the pc harddrives don't like the bass.