I recently bought a used Khartago amp from a fellow member. It was advertised as a "9" with original box and manual, with very little use. Upon receiving it, it was none of the above. Cosmeticly, I'd give it a 7, looks like it's been knocked around a bit. It did come in the original box, but without the internal packaging stuff, it was drowning in a sea of styrofoam peanuts, last but not least, no manual or paperwork. I wrote back to the seller, no response. Not a big deal to me as long as it works properly. Now, here's where it gets to be a problem. In the last 2 1/2 to 3 weeks since I got it, I've been dealing with the following:
1. Weird "BOING! sound at turn on. Sounds kind of like a cartoon spring sound.
2. Intermittent humm. Sometimes when I walk down in the basement and it's quite, I can hear humm from the amp. I turn it off, turn it back on [BOING!] and the humm goes away.
3. Upper mid-range and treble sound very good thru this amp. Lower midrange and bass are mediorce at best. Using two pairs of speakers I know to have good, clean bass [Shamrock Keelins & Paradigm Studio 60's] the bass I'm getting in my system is not great. Both my Jolida 502 and 707 have better control in the bass, as well as better all around sound. [I figure that's another story for another time.]
4. I can live with all the above [though I'd rather not] but this next on is driving me nut's. A thumping, spitting sound. It sounds like someone tapping their finger on a needle on a cartridge. This only seems to happen every couple days but it's enough for me that, frankly, I'm a bit concerned about leaving the amp on. The preamp I'm using is a Rogue 66 with brand new tubes and no problems as far as I can tell. [for what it's worth, I've heard the thumping both before and after changing the preamp tubes.
Is it possible I maybe have a prototype that was not meant for the public? Maybe a lemon? The S/N of the amp is 2025. Klaus, is there any history of repairs on this particular S/N? At this point I'd sell it but I don't want to pass it along like it was passed to me. I also cannot afford another amp at this time so I'm pretty much stuck with it. Any suggestions on what I should be looking for? I know this amp should sound and work better than it seems to. Any help?