• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Tube amp cost

I just stumbled upon this forum, and I have a love for tube amps. Problem is they are so expensive. What I'm gathering here is that I can build my own? I have a couple simple questions...

How much would a good one cost?

Could a newbie such as myself build it sans problems?

Where do I find parts lists/instructions and the like?
 
Welcome. The best advice I can give is don't even start. Because once you do you won't be able to stop!

1- What is a good one? You can build a pretty nice sounding amp for under $200 from a K-12 kit, a bit more than $200 if you add their chassis. The big cost in tube amps is the "iron", the power and output transformers.

2- Tube amps generally employ lethal voltages. Usually from 200 to 500 volts DC. Are you comfortable working with such voltages? Can you follow instructions and solder? Everyone starts somewhere and with care I think most people can build successful tube amps.

3- Google "tube amp schematics" and see what pops up (hundreds or thousands of sites). You can find schematics all over the place. That isn't the hard part. The hard part is is related to your first question. What is a good one? And the answer to that depends on how much power you need, what music you listen to, how big your listening room is etc.

Having said all that I'll take a chance and recommend a couple of types of amps.

First, search this forum for Mikael's KT88. It is a single-ended design of around 5 to 8 watts. The schematic is very simple and many people here have successfully built this amp (including myself).

Next, not recommending a specific schematic I would look at a push-pull EL84 amp. You should be able to get 10 to 12 watts per channel from a good design. (Some are optimistically rated at 15 to 17.5 watts.)
 
Reply

I have had the bug for a while now, it just takes different forms. When I was 14 I got a job so that I could buy my first amp, an adcom GA-535, and a matching preamp. Bought a pair of Bose AM-5 speakers to go with it as well (didn't know better at the time) I still have pictures of the setup. Got a car and moved on to car audio for a while, and would still be doing so if I had a garage and vehicle, and time to go to all the shows etc. I used a put a lot of high end equipment in cars, (scanspeak, seas, aurum cantus, hiquphon, etc) Decided I was going to build a set bookshelfs for the home and just happened to find this part of the forum....and I got bit.

I can solder and follow a schematic, the jargon may take me a while to pick up on...

By good, I mean relatively low distortion, (I know you sacrafice some with tubes) and enough power to drive a pair of bookshelfs well, I was thinking 15-20 watts but I'm sure it can be done with less. I listen to just about anything that is superbly recorded, for me, it is more about the magic in the setup, not so much the material. $200 sounds reasonable to me :)
 
Eastcoast,

Unfortunately, the inflation genie is loose and materials prices have been on rise. :( Still, you should be able to build a decent 12 WPC amp around a pair of Edcor CXPP25-6-7.6K O/P trafos, for not too much more than $200.

The "El Cheapo" Project I've been involved with for the last 2.5 years will meet your need. The linked thread is LENGTHY, but (IMO) worth your time.

BTW, you don't need a separate preamp, if you build an "El Cheapo". :D
 
Cost?
Your' free time.
Your' hobby allowance.
Your' tool allowance (if separate from above).
Your' free space (pre-amp, new DIY speakers, another amp, more speakers, a sub and of course, all of the parts you buy that add up over time.)


Listening to your own amp/speakers/whatever... priceless!


enjoy
7/10 (who, if pressed for a total "cost", would say..hmmm 1 million dollars should do it.