Basking in the beauty of my Aleph J but being a greedy boy, I can't not be looking toward a future build. That being said I still have a few projects in the que including a FM5, but there's always bigger, better, faster or just different waiting to be enjoyed. The problem, there are so many options out there I haven't a clue where to start?
Any insights/suggestions are welcome as long as there is some explanation as to why.
Any insights/suggestions are welcome as long as there is some explanation as to why.
F6
The combination of transformer gain & phase inversion with the simplicity of an all N-type output stage. Many possibilities to try, especially with higher voltage rails & high transconductance devices.
The combination of transformer gain & phase inversion with the simplicity of an all N-type output stage. Many possibilities to try, especially with higher voltage rails & high transconductance devices.
Did a quick search, looks intriguing. Took a quick look at Jim's post w/ BOM, do you know if there is reasonable availability to parts, I still don't have much of a grasp regarding various JFETs. I could probably find this info with more digging but, since the transformer inverts phase does that mean the speakers get connected in reverse as well?
Aleph is at one end the spectrum. F5 / F5M is at another end of the spectrum. There are many options in between that can use the same chassis and power supply. Then it's a matter of swapping the amp boards. I'd suggest some run time with your AJ and the F5. Write down what you're enjoying (or not) and then ask again. Looking for more power? Like the H2? What do you like about Bass/Mids/Highs for each amp? 3D? Imaging?
Look at all the First Watt amps
Look at the ZM amps, too: https://www.diyaudio.com/community/threads/list-of-zm-projects.375782/
Look at all the First Watt amps
Look at the ZM amps, too: https://www.diyaudio.com/community/threads/list-of-zm-projects.375782/
There is a version of the F6 that doesn’t require the use of JFets in the front end. Check out the F6 Revisited thread and the F6 Diamond board set. Yes, I’m the instigator. 😉
I did score a stash of FQA28N15s with the thought of possibly building a Babelfish XA252 down the road. I am thoroughly enjoying the Aleph and will for some time before my next amp, just looking forward 😉
When you say "at one end ..." what spectrum?Aleph is at one end the spectrum. F5 / F5M is at another end of the spectrum.
I did score a stash of FQA28N15s with the thought of possibly building a Babelfish XA252
how - with small ones, and just one polarity?
small ones (TO247 case) are good for small XA252, which is Plethora of Pinjatas, but you need both polarities of mosfets
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This is for the Revel's? With some nasty dips to 3.7 ohms in the bass and midbass, I would do something that takes advantage of the square law character of the FETs in your next amp. XA252 likely worth looking at (I have not built that one myself).looking toward a future build...
Perhaps I misunderstood someone, or they gave me wrong info.how - with small ones, and just one polarity?
At the moment, but I don't anticipate having them too long. I am interested in 1 of Troel's designs but need to get my woodworking stuff out of storage, and that necessitates making space.This is for the Revel's?
When you say "at one end ..." what spectrum?
Jim "6L6" shared this with me a few years ago when I was building the F5. Prior to that I had an Aleph 3, then Aleph J.
if speaking of amp you did mention, there is a thread ....... and pretty much all info is therePerhaps I misunderstood someone, or they gave me wrong info.

You mean Lynn's ZD25 mini (Holy Grail Follower) or Aleksander/Zen Mod's Plethora of Pinjatas. The Big XA252 uses BIG might PUCKS and is a nice big project worthy of a 5U/500!Perhaps I misunderstood someone, or they gave me wrong info.
Best,
Anand.
Thus spoke Zenathustra! Has anyone else seen a cockroach smile? 🤔Jim "6L6" shared this with me a few years ago when I was building the 5.
That makes it sound like the 2 amps are similar sonically but that the Aleph is more transparent. I had purchased the F5M before I was given the opportunity to build the Aleph, does it make sense, from a sonic stand point, to build the F5?
One might say the F5 is more "transparent" and Aleph is "sweeter". Built the F5M, listen to both, and then see where the adventure takes you.
Interesting, I have been thinking that the Aleph isn't as transparent as the ACA Mini but hadn't felt the desire to swap it out yet to experiment 😉. I was pondering what correlates to my impression, lovely soundstage but kind of like in a smokey room. Was wondering if it has something to do w/ 2nd order distortion but I'm just a Bozo on this bus!
Yeah, I think the F5M is a good choice for next but then...........
Yeah, I think the F5M is a good choice for next but then...........
The F5m has proven to be a wonderful amplifier, and a good use for the FQA28N15. I built mine using standard F5 boards, with selective population of components to realize the F5m design. The complementary P-type FETs were IXTQ26P20P, which are much more available than the FQA36P15.
My next new build will be the ZD25 Mini, also using the FQA28N15 / IXTQ26P20P and a chassis that can handle 26V rails and around 1.5A bias.
My next new build will be the ZD25 Mini, also using the FQA28N15 / IXTQ26P20P and a chassis that can handle 26V rails and around 1.5A bias.
The M2x would be a fun one to build after the F5m. I like the original M2 and with the M2x you can play around with different input buffers, including using the original jfet one.
But build the F5m first if you already have the kit... 🙂
But build the F5m first if you already have the kit... 🙂
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