A Little OT:...I Wanna Make An Amp

[Guitar Dude]

Hey,
I was hoping someone out there might have a few tips for me. You see, recently I've become frustrated at the fact that I don't have the necessary skills to work with any circut that doesn't run off a 9V battery. Over the last year I've been launched into the world of electronics and been pleasantly suprised at what I'm capable of.

Over the last year I took a course in electronics at High School. It dealt with all the basics ("This is a resistor", "This is a capacitor" etc, etc.) and I had the oppertunity to make a number of low-voltage circuts. Throughout this past year I've made numerous guitar pedals with the aid of a schematic and a layout diagram and, while some may not have worked, I feel I'm ready to advance to the 'next step'.

Basically what I want to do is make a solid-state guitar amp that runs off of the mains, but to do this I need a few things.

First of all I need some kind of resource that will tell me all the safety procedures I need to know in order to work with lethal voltages. Unfortunately there are very few people in New Zealand who are knowledgable about guitar amps and their characteristics. I assume there must be an in-depth site on the internet that will tell me what I need to know.

Secondly I need a project that has all the information I need in order to make the amp. I was thinking I would make, say, a 50-100w solid-state amp because they have no output transformer and no tubes to mess around with. I need a schematic and a layout/PCB diagram that will show me where all the parts go and maybe even a step-by-step guide (Not because I'm inept, but because I don't want to @#$% up!). The amp doesn't have to be complicated, just a volume and a tone control would be fine, only one channel, no effects loop...The only thing I need is an 8-ohm speaker jack output (Keep in mind that it's impossible to find out-of-the-ordinary parts in NZ, it's a nightmare finding certain semiconductors)

As I've said before, this project is not intended to be ultra-high fidelity, I'm not intending on even using it, all it is is a builing block. My ultimate goal is to be able to safely and confidently make 100% valve amps, I'm just in one of those situations where you've gotta crawl before you can walk.

Cheers
Tim

PS: If there is ANYONE in Christchurch, New Zealand who is willing to give me a hand PLEASE e-mail me!

[Ansil]

can i make a suggestion. before taking on such a daunting task making an amp that big what about making a smaller one.

i have a nice push pull Solid State amp. that rocks and is around 15 watts or so.

[Jim Jones]

Hi Tim,

Why waste time making a SS amp when you can start with the good stuff.    Here's a great place to get your feet wet - www.ax84.com

Jim

[gez]

If you can get hold of the Babani range of electronics books, see if you can order 'Power Supply Projects' (BP 76) and 'High Power Audio Amplifier Construction' (BP  277) both by R.A. Penfold.

They cost next to nothing, don't take long to read and there's a lot of good practical advice.  The circuits in the Amp book are discrete, and you'd probably be better off using an IC (a lot simpler), but it's still worth a read.  The power supply book is an excellent intro to mains powered projects.

[RDV]

Hi Tim,

Why waste time making a SS amp when you can start with the good stuff.    Here's a great place to get your feet wet - www.ax84.com

Jim

Hi Jim!

I plan to build a P1 and I also plan to get one of your eyelet boards, and use your layout also. Why no Paypal? I hate snailmail.

Regards

RDV

[Jim Jones]

Hi there,

Paypal's a pain in the ass for me.  I'm not in the US and I have no desire to leave a credit card number on file with them.  Besides, my board thing is just a hobby so it makes no difference to me.

Jim

[RDV]

Hi there,

Paypal's a pain in the ass for me.  I'm not in the US and I have no desire to leave a credit card number on file with them.  Besides, my board thing is just a hobby so it makes no difference to me.

Jim

That's fine. Do you have the P1 eyelet boards in stock?

Regards

RDV

[Jim Jones]

Sorry, my Paypal response sounded snarkier than I'd intended, my apologies.

Yep, I have some P1's around I think.  If not it's easy enough to put one together for you if you like.


Jim

[RDV]

I'm sure PP is a pain if you're not doing a lot of volume, no offense was taken. You'll probably see an order from me after the holidays.

Cheers

RDV

[casey]

the little gem is a cool first time amp build.

here are some other sites as well:

http://missionamps.kitamp.com/scholar_kits.html

http://www.stf-electronics.com/

http://www.torresengineering.com/suplowpowtin.html

This is solid state stuff:
http://sound.westhost.com/projects-5.htm

http://www.hoffmanamps.com/

This one is supercool:
http://www.londonpower.com/kits.htm

http://www.allenamps.com/kits.html

http://www.ultratoneamps.com/

http://www.stf-electronics.com/Page0015.Html

Parts is Parts:
http://www.angela.com

http://www.tubesandmore.com/new/scripts/silverware.exe/extpage@d:%5Cdfs%5Celevclients%5Ccemirror%5CELEVATOR.FXP?page=DOWNLOAD


Hope this helps out!  

[dubs]

Anyone tried the str electronics champ head kit? PRetty cheap looks like a good starter in to amp building?

[gtrmac]

The Elliot Sound Products SS amps look like good projects for a semi-beginner and he has PC boards available too:

http://sound.westhost.com/index.html

I might build one of his preamps to use for recording.

I've built two all tube point to point amps so far and they both came out great but you really have to watch out for that high voltage with those things. The other thing is that it can get expensive.

//www.18watt.com is a cool site for Marshall style amps.

[Leftrights]

This may be too small a stepping stone for you but there is a AC powered practice amp in Craig Anderton's book Do it yourself projects for guitarists.  I've seen pedals that are more complicated.  The whole thing is built around one power amp IC (LM383) but it might be something to get you started.  I don't suspect it sounds really good (Anderton says its good for "tuning back stage") but you said that you didn't really want to use it anyway.

As for safty, don't lick any really big caps. :wink:

[runmikeyrun]

ahhh... high school electricity class!!  Brings back fond memories.

We had these kits, musta been from the 70s.  Big wooden box with a power supply, oscilloscope, and some other things.  A lot of stupid, pointless series, parallel, and series-parallel circuits involving a couple of light bulbs but it beat the basics into me.  I can pretty much figure out multiple speaker loads without a paper and pencil after all that.

Try sharpening a pencil at both ends, clipping a + lead to one side and a - to the other.  Starting at 0V, slowly crank it up to about 300VDC.  Oh yeah don't do it when the teacher is around!!  The wood will start to smoke and then burn off until there is nothing left but the graphite, which will glow cherry red then white hot until it snaps.  Set off the fire alarm with that one day when a substitute teacher was in.  Also works with those mechanical pencil leads without the smoke and the fire.

[Ansil]

This may be too small a stepping stone for you but there is a AC powered practice amp in Craig Anderton's book Do it yourself projects for guitarists.  I've seen pedals that are more complicated.  The whole thing is built around one power amp IC (LM383) but it might be something to get you started.  I don't suspect it sounds really good (Anderton says its good for "tuning back stage") but you said that you didn't really want to use it anyway.

As for safty, don't lick any really big caps. :wink:

that is the second book that states that.. the first one.  uses a different chip and is actually quite nice.  

i would still go with a push pull configuration of two lm384 since the 383 is on the obsolete list.

[MarkDonMel]

I had a quick question about the 18watt.com thing....

I was checking out that site, which is pretty cool, but I followed a link and ended up at another site selling the 18w amps for like a grand or two...Is that right?

Also, are these things really 18watts?  Im not expert, but I think I saw 4 power tubes in that thing.. I could have been looking at a schem for another circuit...


Thanks, Matt.

[jimmy]

ansil, could i get a look at that 15 watt rig?

jamesm88ATtpg.com.au

cheers
Jim

[Doug H]

If you want to get started building a tube guitar amp, run- don't walk to ax84.com. It is the best site on the web for learning how to build tube amps.

Doug

[Jim Jones]

Also, are these things really 18watts?  Im not expert, but I think I saw 4 power tubes in that thing..

Hi Matt,

Yep, they are in the neighbourhood of 18 watts.  They use a pair of EL84's for power tubes (cathode biased) and a couple 12AX7's for preamp tubes.  Technically the "first" 12AX7 is the preamp and the second is the phase inverter.

Jim

[MarkDonMel]

Cool, thanks Jim.


Anyone know of a book or website that will tell me about safety precautions.  I want to build this amp, or the ax84 or whatever, but it will be my first amp build.  I do have a gift card from barnes and noble so if anyone knows of a comprehensive basic electronics/saftey book, I'd be most thankful.

Thanks, Matt.