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5u4 4th February 2006 03:50 PM

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I've recently completed a Fi-Primer Loftin-White. Tubes are Sovtek. OPT's are Transcendar I got from e-bay; they seem to be exellent. Power transformer & choke are custom Electra-Print. I used Shottky Cree doides & later added a standby switch as turn on surge went above 500V. Voltages are within +5% except for the driver which I need to bring down some. Sound is very neutral with extended lows & highs. There's no euphonic mids, soggy bass & rolled off highs one might expect from a SE amp. Micro detail is very well defined, easily revealing double tracked vocals, ect. It's also easily driven by a CD player/passive preamp. This is my third major project, the first being a SE amp using a Svetlana 811-10. The L-W is much better sounding. The second was a EL-509 OTL which is a very nice sounding amp, but doubles a s a space heater. So far I'm very impressed with this amp. Let me know what you think.

Burnedfingers 4th February 2006 04:15 PM

Very Nice!

5u4 5th February 2006 01:11 PM

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And the underside.

rcavictim 5th February 2006 01:23 PM

Exceptionally clean construction inside. Nice job!

kevinkr 5th February 2006 05:36 PM

Super nice! I bet it sounds really good too.. I googled transcendar the other day, are their prices competitive or expensive?

5u4 5th February 2006 10:52 PM

Thanks, I really like the sound of this amp. It easily drives my 90db speakers in a small room. I think the circuit designer got it right.

I found the Transcendar OPT's on e-bay by searching for "300b" There's a pair for sale every couple weeks or so. The price is on the low side & a good value. They are made in California, 3K pri., 100ma., 8 & 4 ohm sec. I measure around 268 ohm pri. dcr & they are very well matched. They have black cloth cemented around M6 lams & 18g teflon leads. Interleaving on pri. & sec.

kmtang 6th February 2006 12:11 AM

Hi 5U4,

What is the driver tube you are using?


slowmotion 6th February 2006 07:28 AM

Very nice :cool:

I especially like the inside!

cheers ;)

5u4 6th February 2006 07:45 AM

Sovtek 6SL7 SRPP.

5u4 6th February 2006 02:49 PM

Thanks, everything has its own ground wire & is star grounded to a screw near the input, except power transformer CT & C1 share a ground. For the most part signal is in one bundle & PS is in another bundle. Don't know if this is the best way to do it or not, but it works & notice no problems. The amp is very quiet & channel seperation is very good.

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