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FS: F4 clone and 4P1L preamp integrated

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Hi there,
I am selling one of my "too many amps built lately".
It is a F4 clone with an 4P1L integrated preamplifier. The combination is indeed reqarding: a power buffer driven by a very good sounding direct heated pentode in triode mode. The input sensitivity is better the 2Vrms for full 25Wrms delivered into the speakers. I used two enormous heatsinks 10.08"X8"X2.875" from heatsinkUSA. They are comfortable warm. The power transformer is Antek 400VA followed by SiC rectfiers and Nichicon gold tune KG(total capacitor bank of 60mF/35V. All components are high quality, low noise.
The preamplifier can be seen at http://www.diyaudio.com/forums/tubes-valves/190857-4p1l-dht-line-stage-94.html#post4494660. It mounted on #10 threaded rods.
Volume control is provided by two Alps RK27 potentiometers 100K.
The amplifier has two separate Carlings lighted power switches. The left one is for main amp and the next to it is the one that powers the preamplifier, so one can switch them in the right order to protect the speakers.
The case is made of 3/4" oak boards stained with English chestnut and 3 urethane top coats. Inside I used 5 mil copper sheets for screening.

Total cost of the parts was around $900. The amp weights about 50 lbs, shipping weight is around 58 lbs from 06851.

If you are interested, please PM me with an offer ( that includes shipping of your choice). I would be happy to recover most of the cost of parts.


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This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.