GigaWatt

i always wanted t build one... buying one is too expensive... but if i would have to choose one that is prebuild, i would go with some of the following...


Jolida JD300B


A powerful Class A Single-Ended 300B stereo integrated amp with dual tube rectification. Potted transformers and incredible realism. 8 watts of pure music for sensitive horn and Lowther-type single driver speakers.


Sunfire Avon



A single-ended triode amplifier featuring an Ayon 62B power tube, it is said to offer zero decibel feedback, "pure class A" operation for "3D holographic sound," a reproduction that amounts to "space illuminated by music."


Antique Sound Lab AQ1001 MK II



Newly updated with higher quality parts and New aluminum chassis. choke filtered power supply for a faster and more dynamic sound. 50 Watts per channel, switches to 29 Watts per channel in pure triode mode. Wide range bias adjustment for other octal based output tubes. Built in calibrated bias meter. Line level subwoofer outputs. Seriously refined real audiophile sound.



but if you are more into building them, which is definitely harder than even building a regular transistor or integrated circuit amplifier, here are some schematics on some simple hi-fi tube amplifiers and preamplifiers.

Mihir Shah - Remake of the Dynacto ST-70

http://online.physics.uiuc.edu/cours...fi_Tubeamp.pdf


12AX7/12AU7 Tube Preamplifier project (a really simple preamp, almost anyone can build it )

DIY 12AX7 / 12AU7 Tube Preamplifier Project


Beauty - Another 12AX7 Based Tube Preamp (also very simple to build )

The "Beauty" - 12AX7 Tube Preamplifier Kit



i also had some other schematics of tube amps and preamps... but the links i tried are no longer working.... so, i guess you would have to use these ones as a starting guide...

if anyone else is more experienced in building tube amps and preamps, please post some links or give some kind of an advice...

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It's not schisophrenia... it's just a voice in my head...

dj_stick

i've got a 12ax7 based stereo valve mic pre, quite warm sound when i drive the input

just remember, if you're after pure, pristine sound, valves won't give you that (unless you don't overdrive them) - most people like valves for the "warmth" that comes from the harmonic distortion of an overdriven valve

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GigaWatt

yeah, i know , i've actually be thinking of modding an old radio amp to fit the job..

but i have a little trouble making the output transformers (transformators), the original ones are pretty old and have a very wide hysteresis characteristic, which makes them impossible to use in a hi-fi amplifier, since the AFC goes up to about 5KHz, and the nonharmonic distortion is terrible (all because of the wide hysteresis characteristic)... i was thinking of coiling new ones, but it's a very hard process, so i just kinda gave up on it... maybe i'll continue modding it if i could find someone who could coil the transformers for me...

i was thinking of overdirving the tube (it's a dual triode, can't remember which model though) just a little bit, maybe increasing the input voltage by 1.2X or 1.4X, not too much... i just wanted to hear some more 3rd and 5th harmonic components .

anyway, if i do happen to mod it the right way, i'll post it for sure...

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It's not schisophrenia... it's just a voice in my head...

ROBSCIX

If you look around the net you can find many plans for building them. They can turn out very nice and have great "musical" sound quality.

GigaWatt

i know , i posted some links when i started the thread ... i have some designs on my own too (actually, two of them)... just on paper though, haven't had the time or the money to build or test them (measure their characteristics)... but i hope i do one day...

one of my designs is a buffer amplifier (just like the last two schematics i posted), but instead of the dual triode 12AX7, i used the dual triode ECC82... it's cheaper, and easier to find where i live, i would have to order the 12AX7 from the net. the characteristics are in some parts even better that the 12AX7, for example: the voltage needed to drive the tube is much lower, and the heating thread voltage is higher, which leads to better stability and overall better performance of the tube... but, unfortunately, the cost of the overall better performance is more power consumption, but the problem can be resolved with transformers that can supply more power...

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It's not schisophrenia... it's just a voice in my head...