After a too long time of hi-jacking the ghetto mod/what tech did you buy today threads with these, I've decided to create a dedicated thread for posting my odd modifications, repairs and purchases of non-computer related electronics. I think it'll work out a bit cleaner than derailing the other threads ever will.
If you think my articles are totally TL;DR, feel free to just look at the pictures or read something else.
If you've got any questions (I know I might be a bit technical at times), be sure to post them, and I'll clarify. New additions at the bottom top, marked with NEW!.
The result is a rather big improvement:
Now, the new one:
The best part is that there's an extreme risk for electric shock if you open it up, spill water on it or even drop it. There are at least four cut off wires that are just connected directly to the wall somewhere in there.
A quick check showed that it would fit a little battery perfectly with some space to spare. It didn't take long to make a fitting PCB for the amplifier chip. I had been planning on making a new PCB for quite a while, as the one that came from the car stereo was fragile and crappy.
The meter is only there for looks, as I don't have any meter that's small enough to fit in there.
I currently own two of their amplifiers, of which one has had all caps replaced, but the other one (that this post is about) hasn't yet. Due to the price of big caps, I've decided to pull the same trick as I did on the Pioneer, but a little more seriously this time.
Since it's quite an old thing that's never gotten its capacitors replaced, it's got quite a lot of noise and humming in the speakers, totally raping the sound quality of it.
Now, the right way to fix this is to order a new pair of capacitors, remove the old ones and put the new ones there. I don't like that way of wasteful thinking. A while ago, I replaced the caps in one of my bigger amplifiers, which originally had two quite large capacitors that had deteriorated enough to make them improper for use in that amp, but they've still got about twice as much capacity as the ones in my Pioneer had originally. So, I take and replace the Pioneer ones with them, right?
Since I'm going the electronics/computer line, I've got a desk for the whole year, as well as access to a quite large collection of small electronic components. I can take stuff to school without having to move it around all the time, which is quite nice with all the spare time that I've got.
One of those things that I've brought there, is my home-made 2.1 speakers that I built in 7th grade. I built the box by myself, put a 6" speaker in it and taped the amplifier from an old boom box on top of it. It worked, but it wasn't exactly hi-fi, with 10% distortion (Which is bad.), and a whole 11W of power.
I took it apart, and found out that it was indeed the control electronics causing the bad sound. The crap Sony had put in there was a joke.
But, they were also nice-enough to put the amplifier on a PCB of its own, just to de-solder and use! It was basically just to put 12V on one pin and audio signal on another to make it work. On top of that, it had four channels and literally 10 times better specs than my old one. 20W per channel at 1% distortion, as well as four channels. It's not super hi-fi, but it's certainly an improvement. It was a jackpot, really, as those chips cost 20€ alone, and the rest of the parts (PCB, cooler, etc) would be another 20.
A fun fact is that the car stereo was rated for 4x40W, only twice as much as it's physically possible for it to output
The red cables are some ugly fixes my mate pulled off to use the super-cool standby mode and mute features of the amplifier chip, fuck yeah! The brown thingies are small capacitors and resistors used to make one of the channels output only low frequencies for the subwoofer, and two others output only high frequencies, for the satellite speakers.
Now, the surprise I was talking about has unfortunately been canceled. We were gonna do this:
The next project for the amp is already in the making: A wired remote control with power button, volume control and some other toys. We're gonna order some parts this week.
Ok, so it seems we could be arsed to make a better attachment system today. We borrowed a drill from electrical installation and made some holes in the amplifier's PCB, and then the box. We stole some distances from a computer and put the amplifier on them. We only used two, and put fat sticky tape between the PCB and box in the remaining corners.
If you think my articles are totally TL;DR, feel free to just look at the pictures or read something else.
If you've got any questions (I know I might be a bit technical at times), be sure to post them, and I'll clarify. New additions at the bottom top, marked with NEW!.
INDEX
21W LIGHTBULB FLASHLIGHT NEW!
10-MINUTE MODEM UPS/POWER SUPPLY
2x18W AMP RIP
SCHOOL SPEAKERS REVISITED: KILOVOLT
NOT-SO-CRAPPY LUXMAN AMPLIFIER CAPACITOR MOD
HALF-CRAPPY PIONEER AMPLIFIER CAPACITOR MOD
SCHOOL SPEAKERS
EMERGENCY LIGHT CONTROLLER BOX THING
I got tired of my ultra-cheap chinese LED flashlight, which barely emits any light at all, so I took it upon me to find parts around the shop to build a better one. The result is the following:21W LIGHTBULB FLASHLIGHT NEW!
A 2.5kg, 21W, three-ish hour rechargeable flashlight. It consists of four components; a plastic housing for the lightbulb, ripped from another ultra-cheap LED light, one 21W 12V lightbulb, the kind you find in the rear lights of cars, one 7Ah lead battery and one huge plastic switch. And tape. Lots and lots of tape.
The result is a rather big improvement:
Not a lot to cheer for. Note that I couldn't be arsed to fuck around with the white balance; it isn't that blue, and the new one has a yellowish tint to it. These pictures are mainly relative.My old light:
Now, the new one:
Quite an improvement! It'll be nice to have around the house now in the dark time of the year.
This is what drawing 2A out of a cheap 12V battery looks like.
Having just moved, the modem in the house is no longer in my room, and the other residents weren't too happy about the big, beige, wall-mounted locker that used to house it. So, I ripped out the innards, took a big red cardboard box, slammed it in, taped it shut and placed it by the modem. Everything is just placed in there. It isn't attached to the box in any way10-MINUTE MODEM UPS/POWER SUPPLY
The best part is that there's an extreme risk for electric shock if you open it up, spill water on it or even drop it. There are at least four cut off wires that are just connected directly to the wall somewhere in there.
Today I acquired some junk from one of the few remaining places on this island that allows scavenging. Among some other funny stuff was a couple of car radios. All of them had nice little amplifier chips, not very different to the one used in Kilovolt. One of them, however, a little Clarion thing, had a nice modular solution to the whole amplifier section.2x18W AMP RIP NEW!
The amplifier had its own little PCB, connected to the rest of the stereo by a couple of little connectors. Clarion had been nice enough to not mix anything else in on the board, so it would be really easy to work on.
Don't need that anymore.
After an hour or two of tracing lines on the board, I could solder wires to where it would connect to the rest of the stereo, and control the chip by myself. It can be a bit tricky getting everything right, as the chips usually have a couple of extra features such as soft muting and stand-by.
Connectors replaced by wires.
After a little fiddling with the power on pin I got it working, and, well, it works just fine. Now I just gotta come up with some use for it.
A heatsink according to the Japs - A fat piece of aluminium.
No matter how cool it was, the school amplifier solution wasn't very practical, having to climb under the table to adjust the volume. Through a strike of luck I found an old high-voltage cable tester in the trash in school. A nice little wooden box with a step-up transformer and a big knob on it, dating back to 1955. As I have no use for such a contraption, I figured I'd rip out the innards and use the box for something.School speakers revisited: Kilovolt
A quick check showed that it would fit a little battery perfectly with some space to spare. It didn't take long to make a fitting PCB for the amplifier chip. I had been planning on making a new PCB for quite a while, as the one that came from the car stereo was fragile and crappy.
A circuit board.
We were out of black and red cables, so yeah.
Mounted and heatsink'd inside the box. Fits like a glove. Green cables for ultimate glory.
Fits perfectly. There were eight yellow wires added afterwards. Totally service friendly.
All parts in place.
The front isn't made out of plastic. It's made out of bakelite, same for the power switch and volume knob.
The final result!
The meter is only there for looks, as I don't have any meter that's small enough to fit in there.
The handle isn't all that beautiful, but looks weren't the no.1 priority with this thing.
Wooden cover and handle makes it quite rugged and mobile.
The speakers are 20W 5" one-wayers. They work good enough to be listened to.
In operation with the matching speakers.
As you may have noticed, I deal a lot with higher-end vintage audio equipment, with Luxman being one of my favourite brands, as they focused on quality in every field rather than sales. Their cheaper options were simply smaller versions of the more expensive ones, giving them a quite exclusive reputation, and a warm place in my heart.Not-so-crappy Luxman amplifier capacitor mod NEW!
I currently own two of their amplifiers, of which one has had all caps replaced, but the other one (that this post is about) hasn't yet. Due to the price of big caps, I've decided to pull the same trick as I did on the Pioneer, but a little more seriously this time.
I start by attaching some fat cables onto the solder joints of the original caps, which have been replaced by some tech on the island from higher-voltage ones. They're rated for 63V, but the amplifier has about 66V over them, making them wear out very, very fast, and they were at about 1/2 of their capacity when I got it.
SOLDERAN
Awesome industrial caps are attached using fat screws.
Screws.
They're big, old, industrial and awesome. I decided to use another pair later on, however, as these have a big-ass screw on the top, which would get in the way once inside the amp.
Caps.
2x10 000µF is now 2x 28 000µF. Well, at least 2x20 000, as the originals are shit. The humming it had is gone, and it'll sound nice until I feel like spending 40€ on new caps.
The result.
So, for many years, I used a half-crappy Pioneer SA-330 amplifier for my front speakers. It recently got replaced by a much, much better one, so it's taken out of service for a while, leaving room for playing around with it a bit.Half-crappy Pioneer amplifier capacitor mod NEW!
Since it's quite an old thing that's never gotten its capacitors replaced, it's got quite a lot of noise and humming in the speakers, totally raping the sound quality of it.
The two capacitors in the Pioneer were at 5600µF when they were new, but I doubt there's much more than 60-70% of that left. (µF is the unit in which you measure the amount of energy a capacitor can store. Most amplifiers have two capacitors between 4700 and 6800µF each.)
The originals in the Pioneer
Now, the right way to fix this is to order a new pair of capacitors, remove the old ones and put the new ones there. I don't like that way of wasteful thinking. A while ago, I replaced the caps in one of my bigger amplifiers, which originally had two quite large capacitors that had deteriorated enough to make them improper for use in that amp, but they've still got about twice as much capacity as the ones in my Pioneer had originally. So, I take and replace the Pioneer ones with them, right?
No. I just add the bigger ones to it using too thin wires...
100% overkill, just like it should be. It sounds a lot better now, I think the originals were a bit undersized from the beginning.
...and hot-glue them to the case!
As some of you may know, I have a lot of "free time" in school. Almost 15 hours a week, there's no work, but still obligatory presence. This has lead to many interesting experiments and projects, many minor, some bigger. The school amplifier is the most fun one out of those according to me. Since a little while ago, I've started adding random, usually oversized stuff to it to pass time.School speakers
Since I'm going the electronics/computer line, I've got a desk for the whole year, as well as access to a quite large collection of small electronic components. I can take stuff to school without having to move it around all the time, which is quite nice with all the spare time that I've got.
One of those things that I've brought there, is my home-made 2.1 speakers that I built in 7th grade. I built the box by myself, put a 6" speaker in it and taped the amplifier from an old boom box on top of it. It worked, but it wasn't exactly hi-fi, with 10% distortion (Which is bad.), and a whole 11W of power.
One day, during the free time, I was raping the school's old Compaq computers in the cellar for parts, when I noticed that they had some really fucking huge capacitors, and lots of them. I thought they would make excellent replacements for the dried-up ones from about 1985 (capacitors age, they won't work optimally for more than about ten years) in my amplifier. A capacitor is basically a very small and very fast battery, which will effectively filter out interference and give a cleaner and more powerful power supply that can handle peaks, such as extended bass tones better. So, I ripped out a couple of motherboards and started de-soldering caps from them and soldering them onto another PCB.
How it used to look a little while ago, same as when I built it three years ago. The metal cover on top is a raped CD-ROM drive. It's there to protect from messy classmates.
That hunk was born to replace three "tubes", roughly half the size of each of the new ones. Sound was improved, with lots of the interference from the AC adapter removed. Still, it wasn't good, so I thought I should upgrade it a bit more, as the whole design was both ugly, bad-sounding and impractical. At first, I thought about ordering some amplifier chip and making a little circuit board myself, but after scrounging through my room, I found an old Sony car stereo that I had used for some toying around with a while ago. It had pretty shitty sound, but I suspected it was just the cheap control electronics causing that.
The result.
I took it apart, and found out that it was indeed the control electronics causing the bad sound. The crap Sony had put in there was a joke.
But, they were also nice-enough to put the amplifier on a PCB of its own, just to de-solder and use! It was basically just to put 12V on one pin and audio signal on another to make it work. On top of that, it had four channels and literally 10 times better specs than my old one. 20W per channel at 1% distortion, as well as four channels. It's not super hi-fi, but it's certainly an improvement. It was a jackpot, really, as those chips cost 20€ alone, and the rest of the parts (PCB, cooler, etc) would be another 20.
A fun fact is that the car stereo was rated for 4x40W, only twice as much as it's physically possible for it to output
The awesome new amplifier.
As this new thing is about 1/5 the size of the old one, we can mount it on the rear of the speaker, above the battery, instead of on the top of the box. A good thing, as desk space is a little limited. The battery is there because power in the room is usually off in the morning when we get there.
Mounting the capacitors
Because that thick 3M sticky tape is friggin' awesome.
It's going to be attached with sticky tape.
The red cables are some ugly fixes my mate pulled off to use the super-cool standby mode and mute features of the amplifier chip, fuck yeah! The brown thingies are small capacitors and resistors used to make one of the channels output only low frequencies for the subwoofer, and two others output only high frequencies, for the satellite speakers.
The amplifier is successfully mounted on the back of the box! It's a bit messy (you should see the rest of the desk), as we had to hurry away to the bus after testing it. I'm probably gonna update this with final results on Monday. I've also acquired another 100% oversized thing to add to it, which I shall reveal then, too.
Mounted!
The amp had fallen off during the weekend, so we had to remove it from the back and just lay it on the top until we can be arsed to make some better mounts. We also added a couple of volume controls (ripped from the old amp, lol) on the satellites, as the filter for the sub makes it pretty quiet.
Volume control for the satellites mounted. Er, well, put there.
Now, the surprise I was talking about has unfortunately been canceled. We were gonna do this:
Add a really, really ridiculously fat capacitor (53000µF, the bank on the battery is 9000µF), but we decided against it, as caps that big are quite expensive, and it'd get stolen within a week.
The next project for the amp is already in the making: A wired remote control with power button, volume control and some other toys. We're gonna order some parts this week.
Ok, so it seems we could be arsed to make a better attachment system today. We borrowed a drill from electrical installation and made some holes in the amplifier's PCB, and then the box. We stole some distances from a computer and put the amplifier on them. We only used two, and put fat sticky tape between the PCB and box in the remaining corners.
The volume controls are for the satellites; one per speaker. To set them evenly, I use a ruler
Sexy.
This is where the beauty is being used. The small speakers are some (actually fairly decent) chinese 2-way car speakers.
Desk.
Speaker tower.
After some interference by classmates with itchy fingers, I've constructed a case for it. It's made out of the case from the Sony stereo I raped. 1mm thick steel, fuck yeah! The only way to get in is by brute force, or endless screwing of big wood-screws. It's sturdy enough to handle picking the whole 8-kilo speaker up and swinging it around a bit.
A TANK
Connections. They're soldered shut. The chap in the background is my desk mate. He's even more of an all-knowing electronics god than I.
Today I got my hands on an old emergency light battery box... thing, that a local school got rid of a while ago. It's got a nice little power supply with integrated battery charger and lots of exposed high-voltage wiring. And, on top of all, it's a big, beige box from 1986. Just how I like it!Emergency light controller box thing
Testing it a little
It's gonna be the home of my ADSL modem until I come up with something better to do with it.
Batteries mounted. Ready for installation.
Installed in my room.
It is going to be mounted on a wall when I move this summer. Might put some small server or something in it, too. If you've got any suggestions, be sure to post them
Last edited by Freezer7Pro (2009-10-14 13:55:07)
The idea of any hi-fi system is to reproduce the source material as faithfully as possible, and to deliberately add distortion to everything you hear (due to amplifier deficiencies) because it sounds 'nice' is simply not high fidelity. If that is what you want to hear then there is no problem with that, but by adding so much additional material (by way of harmonics and intermodulation) you have a tailored sound system, not a hi-fi. - Rod Elliot, ESP
