Wow! It has more than a year since I last wrote anything here. This is embarrassing considering I used to write every few weeks.
What happened? Well, you could see I’m still alive, kicking and soldering but more than that, I have spent more than a year improving on Discreet Monica.
I know, I know, I’m a pain in the arse but with each improvement, you learn a lot more. I improved on her layout, grounding and even incorporated a FPGA for signal processing capability.
Err, in layman’s term, I had to redo the PCB layout through a few revisions (very expensive process I tell you), learn a new (to me) programming language called VHDL (VHSIC Hardware Description Language but to me it means Very Hard Darned Language), program the FPGA to replicate what I had with 14 integrated chips previously, measure and hand match the high precision resistors (a royal pain I have to tell you) etc etc…
All this effort, so that she sounds better and she’s much easier to build. She definitely sounds so much better now but unfortunately, still tedious to build. Is there more to come? Sure there is! But save that for another day.
I then wanted to build a proper All-In-One system. You see, back when we participated in the KLIAV show way back in 2008, I built an All-In-One.
Back then we have the Monica3, Maggie, output transformer coupled 6GM8 and Charlize2 built in separate chassis and linked via interconnect cables, like a typical separate system.
Once built into a single chassis, the sonics gained a quantum leap!
Why so you ask? It could be lack of RCA interconnections, much shorter signal path and more crucially, the much much shorter return path (also known as GROUND) path between components. Simply put, the electrons travel in a much much shorter loop and they are happier :). And my electronics background tell me that the happier the electrons, the better the sound! And so it proved.
That was then, so I had to build something better today. Since we are going on a purist’ path here, might as well go all the way with just a single gain stage throughout the signal chain. And nothing is simpler than a one-tuber aka spud amp.
Over the years, have always wanted to build a spud and back then the popular tubes were 417, 5842 as well as 6C45. There are others but those are usually 2 stages in an envelope. I’m being purist here. I want ONE and ONE only.
The last few years, another tube gained popularity and it’s a Ruskie 6E5P tetrode. I learned a lot about this tube thanks to the fine work done by Bartola Valves as well as Romy the Cat.
Now this little fella is a like a super tube. Specs wise, everything rocks! So much so that I just have to build it!
Also, over the years, I have heard a lot about the parallel feed scheme. I’m not sure how many commercial amps out there have such a scheme. Just shows us hard core DIYers are more cutting edge than mainstream. Ha! So this is a fantastic vehicle to put in everything together.
And so, we have… A Purist’ Wet Dream.
The initial idea was to build this to be mounted on to a wall but since I’m a such a pain the arse, I just can not build a simple amplifier. So 2 power transformers, 2 power supply chokes, 2 plate chokes, 2 parallel feed output transformers and 4 beer cans oil capacitors later… this whole contraption is just too heavy to be mounted on the wall. So now it has legs and it’s going somewhere!
Input takes USB from your Music Machine be it Windoze or Mac and
Output goes to your speakers via the binding post
USB Input – Discreet Monica – modified Intact Audio Autoformer Volume Control – triode-wired 6E5P Magnequest Iron Parallel Feed Output – Speakers!
All in all, there is only ONE gain stage throughout.
Want to know more about this Purist’ Wet Dream? Stay tuned for the next article.
Yeo, good to see that you’re alive, kicking and soldering. All the while I’ve been keeping tabs on you. LOL!
True, good to see you. Years ago it was because of your site that i’ve gathered enough courage to dive into tubes and all the stuff around. I knew nothing and im still alive. And its a bit funny that 6e5p (6e6p) into 6s19p is my main amp now. Keep on
hi miso
nice to hear from you!
how do you like the 6s19p? how many watts do you have there?
6e5p is really versatile. preamp, driver, power, you name it!
yeo
i’m getting 1.7-2W with 2.5k OPT. 6s19p is a great output tube. slim, tolerant, clean and doesn’t need much money ; just likes to be swung 90v peak-to-peak for full power. That wasn’t possible with my existing beloved 6n6p ‘simple preamp’ so i tried 6e5/6p (based on the similar motivation as yours) and liked the result. The overall sound of this integrated amp is mostly about precious detail and clarity. and it’s not bass-shy, possibly something with low Rp. Simplest triode applications, pio caps in psu-s, silvered mica for coupling and shortest wires possible. With Klangfilm OB-s im so happy that i’ve forgot about the next project, 6n6p-4p1l..they just sit in the box for a year.
Yeo,
I did kind’a opposite, I have one HV PSU, Heater PSU,
one set of SE OPT and two set’s of amp’s on one
chassis. 6DN7 and 6C45Pi. I will unplug the pair of
6DN7 and plug the 6C45Pi.
Well, that was the idea, do not have the 6C45Pi yet,
so we will see if it works, but the idea is good, yes? Hee?
I was previous “baron von vulpes” ,but I forgot my psw. 🙁
I am at moment building the combine amp and a docking
station with a AS7 headphone amp.
hi joe!
wow! that’s a great idea! i don’t have enough space in the house to build so many amps so amps that serve double duties are welcomed.
after all, if you built a great power supply, it makes sense to reuse with different tubes in similar circuits.
i will try this out in the next amp i build. thx!
yeo