The low quality GC

[Bonce]

Heres a pic of the amp I finished last night. Its a stereo amp using PCB's from chipamp.com (standard components). The heatsink is from a pentium 1 system, and the transformers have been scrounged from a battery charger and an old valve amp and with the outputs in series give +-18v after rectification (25 amp standard bridge rectifier).

There is pretty much nothing "audiophile" in this setup, yet it sounds absolutely great, and whilst i could improve it in many ways I really dont think I would be able to hear much difference for the money I would pay.

Its currently driving my own CSS Fr125S sealed full rangers and it seems to be able to drive them much better than my previous home made amp.

http://www.freemyimage.com/ims/pic.php?u=7CRGFR&i=618

[owen]

Dude that looks as scary as hell... please be careful

Now an interesting point - thats no ordinary mains transformer you have pulled from your valve amp.. Thats a Parmeko special (I have one in NOS condition) - You could build a nice valve buffer (try Joe Rasmussens recipe) to go with your chips

Have fun, and play safe...

Owen

[jimbo1968]

ditto, last night I was listening to my standard lm3875 chipamp into my sealed fr125s.

Makes me wish for some kind of meet-up where we could all compare efforts.

I think you will have to put it in a box at some time, if only for the protection of animals and small children.

[demogorgon]

Bonce, thats the way diy should look! just has that certain charm.

i would invest in an ordinary xformer though, or scavenge for one.
pentium sinks are grat for gc's, been using them for almost all my amps. used computer psu sinks for my aircooled lm 4780 though.

-Marius

[Bonce]

Thanks for the replies guys. First of all yes it does look scary but most of the exposed mains terminals have been covereed, you would really have to go out of your way to poke something hard to get a shock. I am also currently living with my parents who understand what I do and know not to touch stuff. Next week Im going back to uni where it will be locked in my room with very few people to touch it

About the transformer, I didnt realise it was anything special. Its not in the best of condition since my dad used it as a battery charger about 30 years ago, and so it has some holes that look as if theyve been epoxied over. I dont think I'll be making a buffer though sadly. Im very minimalistic, and hate the thought of sticking a big, hot valve in the signal path

[Bonce]

Just out of curiosity what makes the Parmeko special so special? I realise that its oil filled, and it doesnt seem to get hot when running compared to the cheaper transformer. But what makes it better?

[Nordic]

Bonce, about that tube, I've done it, and won't go without it for a very long time...

[owen]

The Parmeko works was the greatest UK transformer production company. Thier transformers are incredibly built for a long (understatement) working life. The tolerances they worked to were phenominal, and there are those who would argue audible.

I have the mains transformer which is multi tapped (has 6,12 and a small number of HT voltages on secondary) making it very very useful to the valve experimenter.

I also have a nice brace of thier chokes (1 henry at 1 amp!) that was destined for a DC Darling, but I lost some interest in Valves once I started gaincloning.... I still have a few interesting designs that I may get round to one day

Owen

[Eva]

Hi Bonce

Are loudspeakers still allowed in UK (computing) parties?

In my late teens I had a lot of fun in Spanish parties with my four channel TDA7294 bi-amped setup (including 10" woofers and +-40V supply rails), but then the rules were changed to no longer allow speakers at party places (particularly *large* speakers ). It was a pity

BTW: My system looked even more scary.

[demogorgon]

Eva, you suprise me greatly!

never had the guts or the room to take my gear with me to lans, after carrying the 21' monitor, case of coke and my watercooled maxitower i cant be bothered to carry my 12' subs, veroboard amps and the bookshelves

besides, perhaps this is for the best, others dont seem to like deathmetal, and i dont like nerd music
had to sit the entier TG 03 besides a group called "Norwegian Nerds" with 4* cerwin vega's and monster amps. safe to say they didn't play music i like.
ordinary electronic music i can take, but well, the song was called "pink helicopter". performed by to 10 yeard old swedish girls. with really bad techno behind the vocals. 5 days in a stretch. traumatizing.