• 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.

Help with Budget SET amp for Klipsch Cornwalls

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I have done quite a bit of searching on here and cant find what I am looking for and would appreciate some help.

I have a pair of 1983 Klipsch Cornwall speakers rated at 99 dB SP (I believe) and what I would like to do is a low budget DIY build of a SET amp between 2-10 watts. I can build the base, and use a schematic with some help. I would prefer point to point wiring but would consider using a PC board for this build.

I have moderate soldering skills (I have built a pair of speakers including the crossovers and a small SS amp).

I am aware of the high voltage of these amps and will look for some pointers from y'all in regards to that.

I listen to mainly Rock N Roll, Pink Floyd, Robin Trower, Iron Maiden, Grand Funk, and an occasionally classical music as well.

My listening room is about 15 ' X 15', wooden floor with furniture.
 
SE - yes, modest cost - yes, triode - no, it's ultra-linear (UL) and based on a Mullard setup for the 6BM8/ECL82.

Let me contact Jeff Yourison, who executed the design successfully, about this thread.
 

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I recommend going for a little more power than the 6BM8, having built it along with others.

6L6 or greater dissipation with UL, or possibly plate to grid feedback would better suited for your listening preference with the Cornwall's. ( I almost bought a set in 1978, but settled for Hersey instead because I couldn't imagine the Cornwall's in a trailer in college.)
 
i built one of georges tubelab SSE - very easy to build and to mod to suit your budget and skill level.
also it is easy to add choke/extra PS cap later on if thats what you want.
id say going with the PCB design probably gives it a higher chance of it all working and being safe for first time tube amp builders. obviously still lots of risk but it is minimised a great deal.
as for sound, im running my tube lab SSE with KT88s in triode mode into Klipsch KLF-10s and love it

good luck
 
A budget needs an amount attached to it. So, in order to make reccommendations you should tell us the amount of money you would like to spend. Do you have any parts already in hand? What about tubes do you have any tube that may be used in the amplifier?
 
Thanks for the replies everyone. I like the sound and options of the Tubelab SSE, but am concerned with some of the post on here regarding the parts list etc. and it being incorrect. I have also started looking up the parts from the list on the website and a few are obsolete? Can anyone who has done a recent build comment on this and post a link to the last and most up to date parts list?

DAK808, my initial budget will be between 2-3 hundred. Then modding it further down the line as I get used to it and have the money to play. I can make my own base and save some money that way.
 
DAK808, my initial budget will be between 2-3 hundred.
Even at $300 you will be 'stretched' if you have nothing in your 'junk bin', IMO.
Just paying shipping charges if you end up using several suppliers will cost a fair bit.
Check George anderson's (Tubelab) ideas on building cheaply - he has some good ideas on transformers and components.

Finding an old stereo tube console at the dump or 'Free' on CList would be a good start at a simple amp.

I don't think you will fit a 2A3 amp into a '$300 max for everything' budget....but you might manage it.

At least $100 + shipping for transformers for any SE amp, so you want to try relatively cheap tubes, IMO.
www.thetubestore.com - 2A3 Tube Types
 
Danconway327,

As promised, here is the implementation of a 6BM8 amp that Eli, me and some others worked on. It sounds pretty good, very easy to listen to. Loud enough to fill a room pleasantly (it doesn't crank to party levels).

And inexpensive, to boot.

Jeff
 

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Danconway327,

Here is the 12AB5 amp I mentioned earlier. Eli intended this to be a cheap SE84 knockoff. It sounds very detailed and the trioded 12AB5s produce good bass and treble. This one is capable of higher volumes than the 6BM8.

Note: The amp schematic says "Draft" but it is the final build I implemented.
 

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The remarks about the base cost of magnetics and the cost to ship them are spot on.

The 6BM8 amp takes a pair of $29.84 Edcor GXSE10-5K O/P transformers. The B+ supply uses a $16.37 Triad N-68X isolation transformer energizing a SS diode "full wave" voltage doubler arrangement. Include a filament trafo and (possibly) a B+ filter choke, to round the package out, and magnetics base costs are remarkably low. 😉

A build of the 6BM8 amp will not exceed budget. 😀 Less than $300 is a realistic expectation.
 
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