I'm in the F-5 camp, but its the only Pass power amp I have built. Variations on it, Dual out put Cviller boards and F-5balanced are on the building table, as well as Aleph, both mini and a larger to be determined model. I built the F-5 because of the tremendous popularity of the build, and it seems to have more beans than some of the others, which I need in most of my systems. I like it so much I've got another getting close to done, if I could find a little more time.
Russellc
Russellc
Well, not sure if this is even on topic, considering the DIYaudio setting, and Nelson's modern designs' own attributes.
But, my favourite Nelson Pass amplifier is the Threshold 400A. I'm not even sure "favourite" really describes how I feel about the amp. "First Love" might be getting closer. "A revelation" might be another possible choice.
Were it not for Pass's 400A, which I encountered as a 19-year old working my dream job at the time in a mid-to-high end audio store I eventually ended up owning (along with 3 partners), and which we sold alongside some very capable competition, I may well not find myself an audio nut today.
I moved on to a different career after that gig. I moved away from the pursuit of HiFi as a thing to itself in the process ... although that shouldn't be read as abandoning a quest for good sound. I was doing live recording and mixing for a decade after that (before changing careers again ... a rather larger jump the second time, to a field about as far away from music as you can get. Still doing that one, actually).
My tolerance for poor audio quality hasn't abated in the time since, though ... I didn't buy my first CD until about 1997, and actually have never owned a dedicated CD player in my life ... they didn't sound good to my ears, at least not enough to move into the big rig. Like many people these days, I moved to a music server for my digital sources, although I probably did it sooner than most. Still, my house contains the same stuff other members of this forum would have no trouble identifying as the home of an audio enthusiast.
Nelson's 400A didn't sound like a vacuum tube amp to my ears. What it did sound like was more along the lines of "not like a solid state amp, and not like a vacuum tube amp either, but with some qualities borrowed from both".
Although I'm a vacuum tube amp owner now, I still appreciate solid state and you'll find some SS gear around my place, and look at a choice as not being between one or the other, but between two products on their own merits. Not only that, but I consider Class A and Class AB, regardless of the silicon or glass content, viable options if your list of criteria consists of just one bullet point.
The 400A changed my perception of what was possible in this art. In a way, it kept me in the game, long after I was no longer involved in HiFi on a daily basis, confident that we don't know everything there is to know about the quest. It's a part of what forces me to ask the question every time I critically listen ... why can some particular amps, after all we know and all we can measure, sound so different? And that question is the fundamental reason I find myself on this forum.
In my current job, although it's not the reason I do it nor the reason my clients hire me, I sometimes change people's lives, forever and in a good way. Nelson Pass had that effect on me, probably just as inadvertently.
Maybe it's a romantic attachment, a love of a sound reproduction memory that is best remembered, not revisited. But I can say without any hint of sentimental nostalgia that I've looked for a bit of what the 400A had in everything I've chosen to use since.
But, my favourite Nelson Pass amplifier is the Threshold 400A. I'm not even sure "favourite" really describes how I feel about the amp. "First Love" might be getting closer. "A revelation" might be another possible choice.
Were it not for Pass's 400A, which I encountered as a 19-year old working my dream job at the time in a mid-to-high end audio store I eventually ended up owning (along with 3 partners), and which we sold alongside some very capable competition, I may well not find myself an audio nut today.
I moved on to a different career after that gig. I moved away from the pursuit of HiFi as a thing to itself in the process ... although that shouldn't be read as abandoning a quest for good sound. I was doing live recording and mixing for a decade after that (before changing careers again ... a rather larger jump the second time, to a field about as far away from music as you can get. Still doing that one, actually).
My tolerance for poor audio quality hasn't abated in the time since, though ... I didn't buy my first CD until about 1997, and actually have never owned a dedicated CD player in my life ... they didn't sound good to my ears, at least not enough to move into the big rig. Like many people these days, I moved to a music server for my digital sources, although I probably did it sooner than most. Still, my house contains the same stuff other members of this forum would have no trouble identifying as the home of an audio enthusiast.
Nelson's 400A didn't sound like a vacuum tube amp to my ears. What it did sound like was more along the lines of "not like a solid state amp, and not like a vacuum tube amp either, but with some qualities borrowed from both".
Although I'm a vacuum tube amp owner now, I still appreciate solid state and you'll find some SS gear around my place, and look at a choice as not being between one or the other, but between two products on their own merits. Not only that, but I consider Class A and Class AB, regardless of the silicon or glass content, viable options if your list of criteria consists of just one bullet point.
The 400A changed my perception of what was possible in this art. In a way, it kept me in the game, long after I was no longer involved in HiFi on a daily basis, confident that we don't know everything there is to know about the quest. It's a part of what forces me to ask the question every time I critically listen ... why can some particular amps, after all we know and all we can measure, sound so different? And that question is the fundamental reason I find myself on this forum.
In my current job, although it's not the reason I do it nor the reason my clients hire me, I sometimes change people's lives, forever and in a good way. Nelson Pass had that effect on me, probably just as inadvertently.
Maybe it's a romantic attachment, a love of a sound reproduction memory that is best remembered, not revisited. But I can say without any hint of sentimental nostalgia that I've looked for a bit of what the 400A had in everything I've chosen to use since.
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Not familiar with Aleph F-4....I assume Aleph 4? I'd like to see that build...
Russellc
There is a thread on the Pass Labs tab with my progress so far.
It came to a bit of a halt with wife No. 2 F****** O**.
It's just been brought out of hibernation again and the output stages are being built.
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