Newbie wanting a little direction

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Hey, I'm new to the DIY audio realm. i was just wondering if there is a place i could go (aside from the forum), that has a tutorial or additional info? im reading the forum here and learning a lot, but i want to start out building a really small amp (~15-40W), and just kinda work from there.

is there a place that could kinda guide me through (or even a KIT), that would be easy for someone that has NEVER done anything like this before? im fairly knowledgable in general, and can learn quick (i used to be an engineer my first year in college).

i just want a really simple amp to build as a stepping stone. i wnat to eventually build a 1Kw amp of course, but baby steps right?

thanks guys. and no "just read the forum" responses please, i realise that, and i am doing that, but there are no kits on here...
 
I thought not so long ago you were one of those die-hard video nuts who wouldn't touch audio for anything. Anyway, since you've finally seen the light, you should check out Elliot Sound Projects at http://sound.westhost.com . This is one of the all time audio shrines of the internet. You should also look at http://www.epanorama.net for schematics and stuff. Something else you should do, which will increase your audio knowledge by several orders of magnetude, is read Randy Slone's "High-Power Audio Amplifier Construction Manual" and Douglas Self's "Audio Power Amplifier Design Handbook."

There is no need to start out as small as 15-40W. Rather, 50W is a good starting point. The first power amp I ever built was a 50-60W amp from ESP (project03). It was really simple and only took an hour or so to make.

Good luck!
 
I second the notion about those 2 books. Both are excellent.
One of the authors, Randy Slone, has a business on the side, http://www.sealelectronics.com
If you want to start with a kit, he has a few smaller-ish sort of kits. Although I have never built one of his kits, it looks like you get pretty much everything you need with them(heatsinks, etc.) along with reallt good documentation. Also, he is extremely helpful when it comes to troubleshooting or any explanations you might want or need. I have emailed him several times and he has always replied quickly(one time he replied in only 80 minutes!!!).

Anyways, since you are new to this, I think a kit is a good idea. It will keep the possibility for error and frustration to a minimum. If you decide to go with a kit, make sure you will get the support and documentation you need.

Good luck!!! :D
 
cool cool.

my only concern here is cost. i just casually was looking at prices for some of the amps, and noticed they were like $100+. my DIY projector has kinda depleted most of my "toy" fund, so i don't have much for this project really...

could you guys give me an idea of price ranges for these products? i would eventually like to build my own 200W or so amps for my mains... i noticed some of the more advanced projects got EXPENSIVE

also, only last question (maybe, hehe), what about quality? am i going to be able to build something that will sound not only reasonably good, but exceptionally good? i would really really like to build custom amps (as mentioned above) to power my PSB speakers. would it be possible to really create something great in quality?

and only last thing, Kilowatt, the only reason i got into DIY-video was because i needed a projector to go with my audio system. audio comes first in my book. having a PSB image setup, with 140x5, or 320x2 in stereo, with a lousy 19" display, i needed something better :) you don't even need to convince me audio is great, i'm already there, and have been there. long time subscriber to stereophile, home theater, stereophile guide to home theatre, and CMJ new music monthly. (i usually skip past the video stuff too....)

cheers guys, hopefully you can help me with these questions and any more i may have along the way.
 
frugal-phile™
Joined 2001
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If you want to start out with a kit, want to keep the budget down, and yet end up with something quite decent, this Q-Kit is a real sleeper. Essentially an LM1875 gain-clone kit. There is a lot more info at the AmpChip DIY forum to help you optimize or mod the design supplied in the kit.

You will need to supply heatsinks, case & power-supply (one local fellow just uses a pr of 12V car batteries) which will be the pricey part of the amp (it would be hard to keep the cost of these below the $16 USD cost of a pair of the amp kits).

dave
 
Many of Slone's designs sound great (well, I haven't actually heard any), and he gives PCB patterns in his books, so you can make your own PCB's and save quite a bit.

I made my project03 for almost nothing because I already had most of the parts, including PSU and heatsink.
 
heatsinks are no biggie.

my last hobbie (before the projector thingie) was computer ultra cooling. i can get heatsinks and all sorts of cooling units for nothing. 100x more efficient than what i see being used here in the forum. (plus, for testing, i have an old watercooling unit i built, that can cool even the hottest computer CPU down to just a few degrees above room temp at FULL load. btw, cpu's use around 60amps. yes, 60 amps at full load.)

so cool. how much do PSU's run? and where do i get those? i would rather not build my own quite yet, becuase i dont want to shock the sh** out of myself, which i imagine i would do.

and i saw you can send your PCB designs to people, and they can make them for you, for cheap. is this true? how much would it cost to have someone make a PCB for me?
 
A good source for me, when I first started out, was electronic repair shops. I got cases and power supplies galore for nothing, I mean free. Most of them have these laying around that are junk for some reason or other that they can't give away. Tell them you are new and learning and be sincere and they will go out of their way, and don't be disuaded by one grouch just go to the next shop. A word of warning, you will be surprised at how new some of this junk really is.:D
 
Well cowanrg making your own PCB is damn easy with the photo resist method and can yeild some really good results (alot better then I expected, looks as good as the pros to me). I always used protoboard or did point to point until I built a discrete active crossover, 24dB/octave complex buffers, part count in the 300s, so I had to use a pcb, works great too.

As for building your own psu, it's the easiest part, a piece of cake compared to the audio circuitry, basically you've got transformer(s), rectifier(s) and caps (unless you want to get all fancy). Most of the cash will be in the transformer(s) the caps aren't that expensive, unless you get really big ones. I'd highly reccomend building your own power suply. As for shocking yourself, just don't touch the caps until you've discharged them...

As yes if you DIY you can make something sound exceptionally good. But if you don't have much to spend then it'll be harder. Although my first project (an LM3886 based 5 channel amp) cost me the price of the transformers and the rest I already had or got free samples of. So if you want something easy to start with go with what planet10 said, an LM1875 based amp would be great to begin with.
 
Water cooling. That's cool. I pumped about 800W of heat into the cooling system for my big amp and it didn't even rise quite 1 degree C above ambient. I love water cooling!

As for PCB's, a 3"x5" plain copper clad board is $2.59 at Allied Electronics. A presensitized one is $5.98. This is what someone would almost certainly use if they made a board for you, it's the only practical way to make all but the simplest circuits. 1 gallon of FeCl3 is $25.14, and you can probably make about 40 to 50 3"x5" single sided boards with that. So that is about $0.50 per board. Developer for the poto-resist is $8.35 for 17oz, and you can make a great many boards with that, I'm not sure how many, but probably about 30. Let's say $0.28 per board. If you add all this up, it's about $6.76, but someone would probably double that if they made it for you. You can make one yourself though in about an hour with this stuff if you have fresh, warm FeCl3, and once you get good at making them, if you're not already. I'm sure you can find prices for Slone's ready-made PCBs too. That would be the easiest route if you use one of his designs, if you're willing to pay the money. ESP also sells boards.

For PSUs, I'd tend to agree with PassFan.
 
nice. well, i gotta get some sleep for tonight, but im going to try and read most of that information tomorrow, and try to maybe order that cheap model first.

my ultimate goal here is to make my dad some powerful monoblocks (like 250W @ 4ohm) for his PSB goldi's. (and similar ones for myself).

so, if i get good at this, (which im sure i will), ROUGH estimate on how much a decent pair (single pair) of like 250W (4ohm mind you) monoblocks would cost? just electronics and power supply, casing not included. im just curious.

you guys have been great. im impressed. once i get all this down, i will do my best to pass on the info to the next newbie :)
 
planet10 said:
If you want to start out with a kit, want to keep the budget down, and yet end up with something quite decent, this Q-Kit is a real sleeper. Essentially an LM1875 gain-clone kit. There is a lot more info at the AmpChip DIY forum to help you optimize or mod the design supplied in the kit.

You will need to supply heatsinks, case & power-supply (one local fellow just uses a pr of 12V car batteries) which will be the pricey part of the amp (it would be hard to keep the cost of these below the $16 USD cost of a pair of the amp kits).

dave

Hey, I have read pretty much all the info on all those sites now. (the beginner tutorials anyways, not the advanced stuff yet). Wow, my head hurts, a few hundred pages later, I have an idea what's going on.

But had a couple more questions, i was looking at that kit you linked, and you say it needs power supply, would a computer PSU work? I have one that is a 500-watt. And if not, they say they have a kit that works, but i was unable to find it? do they sell a suitable kit? i would also like to try my hand at building PSU's.

and lastly, does anyone out there want to sell any of their old equiptment for cheap? dont want to go out and buy a ton of stuff just to find out im not into this. so, if anyone has some decent stuff to unload, let me know.
 
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