I believe in deliberate aiming at specific THD Spectra during construction of amp/preamp, also having as major factor overall level of THD
so, no "voicing" at all, at least not in (pejorative) meaning as I see it - trying combinations what's going to sound better, without any clue what are reasons
as it is, result of above mentioned deliberate approach, there is much smaller sound difference between Irreverent and Tanka, than one is usually expecting; so, do not really expect that much Sugar to make any significant difference
same applies for difference between Iron Pumpkin and Tatanka; hope to present properly these too, these days
that's strictly mater of personal preferences; I believe in some cases there is something as too much Sugar ......... say combining SissySIT (more an THD Generator than a Amplifier) with common tube preamp of yesteryears;
but I don't have these problems - I'm not using nor building tube preamps of yesteryears, and I'm deliberate in trying to make preamp as much sonically invisible is possible, then adding all Sugar I want with amp itself
and, good to not forget - 6Ж52П is E810F
that's Cojones, if you ask me ..... king of xconductance, on par with mighty EC8010
if I ever make Tatanka SE for my own use, it'll be with 6Ж52П
Not having a clue…something I’m really good at! 🤪
System synergy seems like dumb luck sometimes.
Though, ZM toys makes it easier to get something right 😉
I thought at first these two new threads must be an admin error due to a title change. I don't know how you have the time, ZM. Amazing work!!
I've been dabbling with a M5Stack Dial to use as an IC2 controller for a relay volume. It was easy to get the display to work, but I haven't yet gotten it to communicate via I2C. (If anyone has used an M5Stack Dial successfully, LMK...)
I've been dabbling with a M5Stack Dial to use as an IC2 controller for a relay volume. It was easy to get the display to work, but I haven't yet gotten it to communicate via I2C. (If anyone has used an M5Stack Dial successfully, LMK...)
well, there is a video somewhere ...... lemme see if I can find it ...... nope, I can't
anyhow - there is a short vid where Pa, to paraphrase it - sez that he likes to build amps, but he also likes to sell them
it took me years to get to same stance - nothing wrong with selling your Drek, as long Customers are having all reasons to be happy
so, easy explanation - I'm doing this both as my day(night) work and as a hobby or, rather, passion.
problem being - as I'm enjoying this that much, there is not much time left to other things I like doing
ditching movies and series helps some, to leave some time for reading.
now I need to work how to finally find time to play with my bikes
I have mostly "concepts of plans" 😏 , though I do have a completed preamp that hasn't yet been written up to post.
Yea. Watch out for audio band oscillation on that one tho. Needs tight gridstoppers and maybe also a bead on the anode.
yeah, worth reminding......... though - when you pay the price of learning on own mistakes, it becomes regular practice with such type of tubes
btw. I did mention - what I found, even after decades of messing with toobz and making all sorts of mess..........
in past, I routinely wired 2 triode systems of, say, ECC88 in parallel, and even several tubes in parallel (anyone remembering CJ ART preamp?)
this time, my first decision was to use exclusively 88 in both SE and Bal iteration of preamp
logically, in bal, each triode section in one envelope is serving one signal phase; no problems there
now, for SE, I've just wired 2 systems in parallel, so xconductance doubled, all good, yadayada
then I realized that preamp is sometimes developing sort of hum/oscillation when powered on, and in most cases zing vanishing after some time
tried everything to cure that - changing grid stopper values, introducing beads everywhere, varying elevation of heater supply, varying impedance of elevation network, changing value of decoupling cap in same network, then varying heat-up time/HV delay ...... then realizing that I have that problem with some toobz, while with some other (production) there is no problem at all
well, then I was just puzzled for few days, without actually trying anything
so, I tried just one thing I didn't tried - introducing separate cathode resistors, as common way of equalizing shared currents in parallel elements - and that did it
explanation was - as I connected these triode systems, there is no single link in chain where I have any resistive loss ( yeah, being anal about that) and as tube as whole is practically biased/fed with CCS in cathode, even tiniest difference in transfer characteristic between two triode systems is resulting in see-saw effect
so, you have it, solution was to choose - either introducing small cathode degeneration resistors (aaaargh!), or simply desoldering toob socket, pulling all socket pins for one triode system, and soldering it back again, leaving said triode system just chillin' in da breeze
that was solution/approach, at least for batch of pcbs already made for ECC88
after that, I tried russkie E180F and PC900, choice ended on E180F, simply because I can get NOS ones easy, while my (big) stash of PC900 is (unfortunately) from production time of EI RC when everything in Yugoslavia/Serbia/whatever gone to hell, and big percentage of them are duds
in past, I routinely wired 2 triode systems of, say, ECC88 in parallel, and even several tubes in parallel (anyone remembering CJ ART preamp?)
this time, my first decision was to use exclusively 88 in both SE and Bal iteration of preamp
logically, in bal, each triode section in one envelope is serving one signal phase; no problems there
now, for SE, I've just wired 2 systems in parallel, so xconductance doubled, all good, yadayada
then I realized that preamp is sometimes developing sort of hum/oscillation when powered on, and in most cases zing vanishing after some time
tried everything to cure that - changing grid stopper values, introducing beads everywhere, varying elevation of heater supply, varying impedance of elevation network, changing value of decoupling cap in same network, then varying heat-up time/HV delay ...... then realizing that I have that problem with some toobz, while with some other (production) there is no problem at all
well, then I was just puzzled for few days, without actually trying anything
so, I tried just one thing I didn't tried - introducing separate cathode resistors, as common way of equalizing shared currents in parallel elements - and that did it
explanation was - as I connected these triode systems, there is no single link in chain where I have any resistive loss ( yeah, being anal about that) and as tube as whole is practically biased/fed with CCS in cathode, even tiniest difference in transfer characteristic between two triode systems is resulting in see-saw effect
so, you have it, solution was to choose - either introducing small cathode degeneration resistors (aaaargh!), or simply desoldering toob socket, pulling all socket pins for one triode system, and soldering it back again, leaving said triode system just chillin' in da breeze
that was solution/approach, at least for batch of pcbs already made for ECC88
after that, I tried russkie E180F and PC900, choice ended on E180F, simply because I can get NOS ones easy, while my (big) stash of PC900 is (unfortunately) from production time of EI RC when everything in Yugoslavia/Serbia/whatever gone to hell, and big percentage of them are duds
Good that you found out and yes it can also differ a lot between different species of the same toob. Cathode followers in general are usually sensitive lo load capacitance causing hf oscillation. General solution being having two Rk in series, upper smaller and lower bigger taking signal out in between, to isolate the networks somewhat.
Bit of my
stash
Bit of my
Nice stash
Back in the late 80s and very early 90s I worked at three metrology labs.
They had tubes.... the warehouse had racks and racks and racks full of tubes. With calibrated tube matching equipment. Part of their task was to provide calibration for the plants, both in R&D and production.
You guys would have loved it.
Actually, they had pretty much everything... op amps, semiconductors, ICs, processors, you name it. We just didn't have any of them East of the Berlin Wall sourced stuff, Couldn't put Mig parts in an F16, you understand?
For a few years, I ran US Mil-Spec tubes in my stereo.
For free.
Back in the late 80s and very early 90s I worked at three metrology labs.
They had tubes.... the warehouse had racks and racks and racks full of tubes. With calibrated tube matching equipment. Part of their task was to provide calibration for the plants, both in R&D and production.
You guys would have loved it.
Actually, they had pretty much everything... op amps, semiconductors, ICs, processors, you name it. We just didn't have any of them East of the Berlin Wall sourced stuff, Couldn't put Mig parts in an F16, you understand?
For a few years, I ran US Mil-Spec tubes in my stereo.
For free.
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