Cheap and Chinese KT88 SE amp

[andrew_whitham]

Originally posted by rcavictim
I see what you mean about lack of upgrade room. Too bad they couldn`t hide the supply electrolytics inside, otherwise it looks OK, but if it were mine those kitchen drawer handles would be gonzo.

those kitchen drawer handles are essential, they are the only cool bit of the amp once its been on for a few hours -

expect they'll go with the box though. (one day!)

Andy

[andrew_whitham]

Originally posted by TomWaits

Andrew, have you redrawn the schematic for a final revision?
Would it be too dumb to try some 807's on this rig?

Cheers.

Shawn.

No I havent drawn it yet, but wait a moment, might as well draw a full line under the project as it is now. I might even have some pictures of the insides too.

the amp itself is available in china with a variety of diferent tubes, some of which look very much like the 807's but since a top-cap scares me I didn't look closely. Really I saw the KT88 and jumped right in...

Andy

[andrew_whitham]

Okely Dokely here's the 'final' version

added a transistorised CCS for the driver stage! note that the MPSA92 could just as easily be an MJE350 but a mistake on the PCB meant that in this case it couldnt (oops)

if you dont like the idea of transistors this just replaces the 33K resistor in previous versions and you'll never know what you're missing

Andy

[andrew_whitham]

and finally a picture of the guts

[TomWaits]

Well done Andy! Now I want one

Shawn.

[chrish]

I have just come across this thread and might be interested in getting one of these amps, or perhaps something similar. My job has me travelling to China occasionally, to Beijing and to Shanghai. Do you think you might be able to post the details of the shop where you found these amps?

Thanks in advance!

[andrew_whitham]

Honestly I would if I could,

I dont speak Chinese well enough to actually do shopping in Shenzhen (and forget "getting by" often the Shopkeeper speaks zero English)

So long story short - I get my friends to accompany me to something that phonetically sounds like "Wah Chan Bey Lau". Then I go hunting to find the same shop I visited last time...

If you do at anypoint visit the Shenzhen area its in the same shop as www.diyclub.cn (that site does work sometimes honest)

On the otherhand If you are visiting Shanghai theres BOUND to be some equivalent gear. I seem to remember a lot of it is built there, so...

Good luck!

Andy