Clik here to view.
MC1/60, E60M, TM100 SE amplifier - Part 1
In the DIY world of triodes amplifier lovers, most people know the best of the large power tubes like the 211/VT4C or the 845. These tubes are easy to source, still manufactured by Chinese, Czech or...
View ArticleClik here to view.
MC1/60, E60M, TM100 SE amplifier - Part 2
Back on the air with amplifier circuitVoltage requirements.We need 600V for the final stage, 300V for driver, negative bias voltage, heater voltage.High voltage is not very high, I can take advantage...
View ArticleClik here to view.
VT25, VT25A Push Pull amplifier Part 1
The 10 is a very old triode and probably one of the first power tube. It's linearity and sound qualities brought this tube a favourite among many DIY's. Dozens of amp and preamp using this tube and...
View ArticleClik here to view.
VT25, VT25A Push Pull amplifier Part 2
All Tango amp in white slim chassis...and fed with good looking and good sounding tubes.Sylvania VT25 bright lightMagic eye for funPhilips 5R4GYS is a perfect companion for the Sylvania VT25Sylvania...
View ArticleClik here to view.
EL84 Push Pull amplifier, the little giant
The EL84 is NOT a DHT, but still a fascinating tube for many triodes lovers (I belong to this group) who recognize its sonic qualities.Great manufacturers like Dynaco, Scott, Leak, Loyez just to name a...
View ArticleClik here to view.
6J5 line preamplifier Part 1
The 6J5 is a general purpose not to say an ubiquitous small signal triode. Its linearity is well known and appreciated by many DIYer's. It is commonly said that what goes in is what comes out. It is...
View ArticleClik here to view.
6J5 line preamplifier Part 2
High voltage requirementsNeedless to say that a good supply, free of ripple, is essential in SE stage that have very bad CMRR. This generally dictate a large capacitor bank at the expense of transient...
View ArticleClik here to view.
6J5 line preamplifier Part 3
Back on the air...Normally there should not be a part 3, but I recently found a few Visseaux 6J5G and put them to good use in my line preamp.While listening to CD's and LP's I know very well I was so...
View ArticleClik here to view.
E140 SE A2 amplifier part 1
A while ago I found some peculiar tubes that I bought for a decent price.These E140 tubes, like the E60M, where manufactured by SFR and it was a reason for me to buy some.SFR tubes are among the best...
View ArticleClik here to view.
E140 SE A2 amplifier part 2
Class A2 amplifiers need a more elaborated driver than the usual A1.Technical approachTo source the E140 grid properly it imposes a low impedance driver stage. It is the heart of this project. I could...
View ArticleClik here to view.
E140 SE A2 amplifier part 3
Tubes selection made, now it's time to mix up all these good things.Before publishing amplifier schematic let's have a look to the driver limitations.High frequency: 12B4A & Miller's effectThe...
View ArticleClik here to view.
Pots and attenuators
In every audio equipment there is a gain or volume control to set music reproduction to an enjoyable level . This control is usually devoted to a simple potentiometer mostly for cost reasons. On pricey...
View ArticleClik here to view.
E80CC SRPP line preamplifier Part 1
This project was initiated by a request of a line preamp with selectable input sensitivity to match sources with different voltage outputs. This preamp should also have a low output impedance to drive...
View ArticleClik here to view.
E80CC SRPP line preamplifier Part 2
SRPP calculationThe heart of the SRPP is the 3 resistors used in this circuit (the upper one is generally omitted but it is bad practice if you want a perfectly balanced push pull). Easy to calculate...
View ArticleClik here to view.
E80CC SRPP line preamplifier Part 3
Power supplyUnlike the 6J5 line preamp I used a CLC filtered supply. I usually prefer the LC for its very smooth ripple behind choke but listening tests demonstrated better dynamic with SRPP. A good...
View ArticleClik here to view.
VT25/VT25A push pull rejuvenation part 1
This amp have been my music companion for more than two decades and the only one I kept among the few I built until I came across the Philips MC1/60 triode.It had all the qualities expected from the 10...
View ArticleClik here to view.
High End Munich 2017
Had the opportunity to get a professional pass for the MOC and I spend 3 days of pure enjoyment listening to some of the best audio gears an amateur could dream for.Also had the chance and pleasure to...
View ArticleClik here to view.
VT25, VT25A Push Pull rejuvenation part 2
On the bench for surgery.This major changes just leave transformers, choke and sockets on the chassis.I also kept the hum and push pull balance potentiometers but removed the electrolytics (replaced by...
View ArticleClik here to view.
VT25, VT25A Push Pull rejuvenation part 3
Wiring and componentsI started wiring the SRPP driver first.It is the trickiest part to build as I favor compact, direct to socket implementation whenever possible. I also like to use soldering lugs...
View ArticleClik here to view.
C3g Line preamp part 1
A rare find initiated this project. A pair of new and mint audio transformers by LIE Belin came into my hands at a moment I was thinking how I could put to good use some tubes I have in stock for a...
View Article