• 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.

El Cheapo ok for a first build?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I've read many (but not all) of the 67 pages on the El Cheapo at Audiophiletalk. It seems like an excellent amp and not too complicated, but I am totally new to this- is it too big of a bite? I like that there is so much interest in it, and the parts kits from Jim McShane makes it appealing too.

Actually for a first first build I will probably do a phono preamp, but would like to have a larger project on hand for when I'm overloaded with work and need to procrastinate ;).

The name itself has me sold on it.
 
Big John,

I am currently nearing completion of my first amp, and it is indeed the El Cheapo. It has not been extremely difficult, just time consuming. I hadn't played with electronics for a good 15 years, so a lot of this has been a learning experience.

Good luck with your choice!
 
I went with the kit from Jim McShane, as I had some concern about being able to pick out the right kind of resistors and capacitors from Mouser or DigiKey.

All of my iron came from Allied Electronics, with the exception of the OPTs, which came from TriodeElectronics. I opted for the 'upgraded' Z565 transformers.

All this talk.. now I just want to go home and finish the thing!
 
I built it and it was fairly straightforward with a good sound. Also lots of NOS parts to swap and change- there are loads of cheap 6AQ5 / 6V6 / 7C5 available.

If you can, get ultralinear output transformers, that way you can experiment between triode, ultralinear and pentode modes.
 
John,

Whatever your 1st build is will be fine, provided it's NOT a phono preamp. A scratch built phono preamp is as tough as things get. Things like layout and grounding are extremely critical. Get some experience under your belt, before tackling a phono preamp.

If you decide to try "El Cheapo", thought must be given to the B- supply. The Allied 6K27VF is no good, for "240" V. zone dwellers. With their dual primaries, a Triad N-77U and a Triad VPL24-2000 will take care of B+, all heaters, and B+ boost. You have to come up with a 50 V. or so 15 mA. negative rail. The 10 KOhm part connecting the 12AT7 cathodes to the tail CCS would become 100 Ω. Using the hybrid bridge shown for rectification, a dual primary Triad VPL36-140 would do nicely.
 
John,

Whatever your 1st build is will be fine, provided it's NOT a phono preamp. A scratch built phono preamp is as tough as things get. Things like layout and grounding are extremely critical. Get some experience under your belt, before tackling a phono preamp.

If you decide to try "El Cheapo", thought must be given to the B- supply. The Allied 6K27VF is no good, for "240" V. zone dwellers. With their dual primaries, a Triad N-77U and a Triad VPL24-2000 will take care of B+, all heaters, and B+ boost. You have to come up with a 50 V. or so 15 mA. negative rail. The 10 KOhm part connecting the 12AT7 cathodes to the tail CCS would become 100 Ω. Using the hybrid bridge shown for rectification, a dual primary Triad VPL36-140 would do nicely.

Yes, I've been digging for info on phono preamps in the last couple of hours and sort of got that impression!
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.