Home project

markwho

As a home project i'm thinking of building a tube amp. I was gonna use the tubes from an old radio and the parts from an old solid state amp i have lying around.
Anyone have any thoughts on this, or anywhere i could go online for a bit more info.
Really interested in trying this out.

Paolo_M

markwho wrote: »

As a home project i'm thinking of building a tube amp. I was gonna use the tubes from an old radio and the parts from an old solid state amp i have lying around.
Anyone have any thoughts on this, or anywhere i could go online for a bit more info.
Really interested in trying this out.

I've built a few valve amps and willing to help you out if you have any questions. You can see some of my stuff on the uTube link in my sig.

There's no parts in a SS amp that you will be able to use.
The power transformer usually supply a split rail of around +-30Vdc, which is no good for valves. You'll need around 400Vdc to ground, plus a negative bias supply and this requires a valve transformer.

There are loads of forums I can recommend, but first how 'bout a little info.
What exactly are you trying to build?
An amp for a stereo, a bass amp, a guitar amp? What features, styles etc.?
Many of the forums are specialist, like some specialise in building high gain guitar amps and so on.
Also on-line suppliers tend to specialise a bit too.

markwho

I'm just looking to build something that makes a bit of a noise, a basic guitar valve amp with an eq, which has an output to run into a speaker, or into headphones, so i can effectively use it as headphone preamp too. Maybe even with multiple outputs. But i havent looked into that the headphone bit yet. Would i overload them? What are the precautions
And i've looked around at some of the amp building kits but i'd like the fun of building one myself from scratch.
Thanks for your help.

Edit: A link to the forums would be nice too. Or are they super secret place where outsiders are forbidden :P

madtheory

A headphone amp is quite a different beast to a guitar amp. You're looking for a multipurpose type thing right? Well a guitar amp has a very high input impedance and is usually mono. A headphone amp is stereo and has a not so high input impedance. Sounds like what you want is something simple...so maybe you should be looking at just a pre amp/ pedal type of thing instead? Listen to Paolo, he knows what he's doing!

Paolo_M

markwho wrote: »

I'm just looking to build something that makes a bit of a noise, a basic guitar valve amp with an eq, which has an output to run into a speaker, or into headphones, so i can effectively use it as headphone preamp too. Maybe even with multiple outputs. But i havent looked into that the headphone bit yet. Would i overload them? What are the precautions
And i've looked around at some of the amp building kits but i'd like the fun of building one myself from scratch.
Thanks for your help.

Edit: A link to the forums would be nice too. Or are they super secret place where outsiders are forbidden :P

Designing and building a guitar valve amp is not "fun". You'll need to put in around 2 years of study (that's what I needed and I have an Electronics degree) and then try out a few FX pedals, SS amps etc. before having a go of designing/building valve amp from scratch.
If you do insist on diving straight in with a valve amp then a kit is definitely the way to go.

You need to be careful with outputs on a valve amp. Headphones are not an adequate load and can't be used.

www.ampmaker.co.uk do a decent Marshall 18 Watt kit. It'll get you Vox AC15 type tones and have a simple EQ. Easy to build, relatively cheap and Barry is pretty sound. He also does a smaller 5 watt "Champ" type kit.

Check out
www.18watt.com
www.sewatt.com
www.ppwatt.com
http://www.aikenamps.com/ excellent tech section
http://www.el34world.com/
http://www.valvewizard.co.uk/ the best valve guitar amp designing/building tech info on the web, bar none.
www.tube-town.net parts and kits
http://www.tubeampdoctor.com/index.php?cPath=96


DISCLAIMER: IF YOU HAVE NO ELECTRONICS EXPERIENCE, AND DONT INTEND INVESTING TIME LEARNING ELECTRICAL AND ELECTRONIC SAFETY PROCEDURES AND GOOD PRACTISES, THEN THERE'S A PRETTY GOOD CHANCE OF YOU SERIOUSLY INJURING AND EVEN KILLING YOURSELD BUILDING A VALVE AMP.
Kits offer step by step guides but these are not paint by numbers FX pedals or solid state amps.
400Vdc is more than enough to kill you if you are stupid enough.


Don't wanna sound like a kill-joy, but I think you're taking this a little too lightly if you're actually serious about it.

studiorat

Great site Paolo. Nice work.

Like the man says, try a few pedals and battery operated stuff first.