Grey,
after I realized that I don't really need 50w on each channel of my active system I thought of using this little thingy for amplification. On top of that I would be well on my way of being fully Pass-ified with the last piece of the puzzle being the active Xover.
How does the DC offset behave over time? Basically, is this thing safe for use DC coupled to the driver?
after I realized that I don't really need 50w on each channel of my active system I thought of using this little thingy for amplification. On top of that I would be well on my way of being fully Pass-ified with the last piece of the puzzle being the active Xover.
How does the DC offset behave over time? Basically, is this thing safe for use DC coupled to the driver?
DC offset isn't likely to be a problem...at least any more than it would be for a "real" Aleph. A few tens of millivolts here and there at worst. It does have a bit of a turn-on thump, though, so I'd use a cap if you were going to use the circuit to run a tweeter. For a woofer...no problemo, go straight in.
Take note of earlier posts about current and rejigger the bias if you need to run a 4 ohm driver. Feel free to run it at a higher rail, if you want a bit more power. Once you get up into the low to mid-20s on the rail voltage, go ahead and build an Aleph 3 or 30. This is just sort of a cute 'toy' Aleph; something to burn up leftover parts.
I'm still waiting for someone to build one in a Pepsi can...
Grey
Take note of earlier posts about current and rejigger the bias if you need to run a 4 ohm driver. Feel free to run it at a higher rail, if you want a bit more power. Once you get up into the low to mid-20s on the rail voltage, go ahead and build an Aleph 3 or 30. This is just sort of a cute 'toy' Aleph; something to burn up leftover parts.
I'm still waiting for someone to build one in a Pepsi can...
Grey
I finished a pair of monoblocks for a friend a couple of weeks ago, slightly beefed up compared to the original Mini A schematic.
I used a 150VA 2x12V transformer per channel that feeds a pi filter with 15000uF - 1,1mH - 47000uF.
Gives 14W/8ohms and 23W/4 ohms, but then I also raised the bias a bit since the guy I made them for has 4 ohms speakers.
I used a 150VA 2x12V transformer per channel that feeds a pi filter with 15000uF - 1,1mH - 47000uF.
Gives 14W/8ohms and 23W/4 ohms, but then I also raised the bias a bit since the guy I made them for has 4 ohms speakers.
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Banned
Joined 2002
Do I do the Mini-A?
...this is a trick question, perhaps?
As I said in the first post of this thread, the Mini-A was something I did as a stepping stone to the Aleph-X. It's basically a cut-down Aleph 3. Nothing particularly weird or original. Somewhat later, one of the installments in Nelson's Zen series featured an Aleph-style entry (#4, I think).
Other variations are possible and I've fiddled with a few of them.
If time permits, I may start another thread or two based on some of the things I've done here, but it's very time-consuming to support a thread; I've got more ideas than I can practically put out. I don't make any money at this, so I still have to show up at a non-audio job in order to keep my daughter in diapers. What with work and eating and sleeping and a few other odds and ends, there's little slack at the moment.
Nelson, incidentally, was not warned about this thread. With the Aleph-X, I kept him abreast of things pretty much from conception--that story has been detailed elsewhere--but the Mini-A was as much news to him as it was to anyone else. If I'm lucky, he'll forgive me sometime during our present incarnations. If I come back in my next life as a microbe, I'll know that I've got some kharma-balancing to do.
Sigh.
I have at least two or three other Aleph ideas that might make interesting threads. I fear that one of them might be close to the Aleph-J (no, I haven't seen a schematic for the J, just guessing), so I won't bother with that. I have not had time to try out the 'Maxi-A' idea yet, so I don't know if that's worth pursuing.
At any rate, I had artwork for PC boards, but lost it in one of the hard drive crashes, or perhaps when the virus set up shop in my machine a couple of years ago. If necessary I can recreate it, but at this point I'd rather move forward and do a new circuit than revisit the old one.
MikeW, bless his heart, was kind enough to adopt the Mini-A. He and a friend of his worked up boards, which then travelled to the four corners of the Earth. When those ran out, he did a revised version. Any audience the Mini-A has garnered has been his doing. Thanks, Mike.
Note that the Aleph patent is still active. Do not attempt to produce Mini-As for profit or a platoon of lawyers will infest your underwear. Your wife/girlfriend/(in)significant other will leave you. Perhaps all three of them at the same time. Don't tempt fate. Though Nelson did not draw the schematic for the Mini-A, it is based directly on his patent and is covered just as much as an official Aleph from Nelson, himself.
You can build one, play with it, use it for a paperweight, or even listen to music with it...just don't sell it at a profit. Don't say that you weren't warned.
Grey
P.S.: They are kinda cute, aren't they?
...this is a trick question, perhaps?
As I said in the first post of this thread, the Mini-A was something I did as a stepping stone to the Aleph-X. It's basically a cut-down Aleph 3. Nothing particularly weird or original. Somewhat later, one of the installments in Nelson's Zen series featured an Aleph-style entry (#4, I think).
Other variations are possible and I've fiddled with a few of them.
If time permits, I may start another thread or two based on some of the things I've done here, but it's very time-consuming to support a thread; I've got more ideas than I can practically put out. I don't make any money at this, so I still have to show up at a non-audio job in order to keep my daughter in diapers. What with work and eating and sleeping and a few other odds and ends, there's little slack at the moment.
Nelson, incidentally, was not warned about this thread. With the Aleph-X, I kept him abreast of things pretty much from conception--that story has been detailed elsewhere--but the Mini-A was as much news to him as it was to anyone else. If I'm lucky, he'll forgive me sometime during our present incarnations. If I come back in my next life as a microbe, I'll know that I've got some kharma-balancing to do.
Sigh.
I have at least two or three other Aleph ideas that might make interesting threads. I fear that one of them might be close to the Aleph-J (no, I haven't seen a schematic for the J, just guessing), so I won't bother with that. I have not had time to try out the 'Maxi-A' idea yet, so I don't know if that's worth pursuing.
At any rate, I had artwork for PC boards, but lost it in one of the hard drive crashes, or perhaps when the virus set up shop in my machine a couple of years ago. If necessary I can recreate it, but at this point I'd rather move forward and do a new circuit than revisit the old one.
MikeW, bless his heart, was kind enough to adopt the Mini-A. He and a friend of his worked up boards, which then travelled to the four corners of the Earth. When those ran out, he did a revised version. Any audience the Mini-A has garnered has been his doing. Thanks, Mike.
Note that the Aleph patent is still active. Do not attempt to produce Mini-As for profit or a platoon of lawyers will infest your underwear. Your wife/girlfriend/(in)significant other will leave you. Perhaps all three of them at the same time. Don't tempt fate. Though Nelson did not draw the schematic for the Mini-A, it is based directly on his patent and is covered just as much as an official Aleph from Nelson, himself.
You can build one, play with it, use it for a paperweight, or even listen to music with it...just don't sell it at a profit. Don't say that you weren't warned.
Grey
P.S.: They are kinda cute, aren't they?
Banned
Joined 2002
Banned
Joined 2002
That's not true. I answer all the (real) email I receive, and I
was answering yours this afternoon when I got interrupted.
I don't receive all the emails sent to me for unknown reasons,
(I comb my spam net, that's not the reason) but what I do get
is enough to occupy a good portion of my workday.
/pass/: should be working on that time machine
was answering yours this afternoon when I got interrupted.
I don't receive all the emails sent to me for unknown reasons,
(I comb my spam net, that's not the reason) but what I do get
is enough to occupy a good portion of my workday.
/pass/: should be working on that time machine
Banned
Joined 2002
Nelson Pass said:That's not true. I answer all the (real) email I receive, and I
was answering yours this afternoon when I got interrupted.
I don't receive all the emails sent to me for unknown reasons,
(I comb my spam net, that's not the reason) but what I do get
is enough to occupy a good portion of my workday.
/pass/: should be working on that time machine
Could my email please be advised so i can further my action's .. as i have superb idea's.. Please email me back nelson.. Or i could directly call you.
It's hard to realize that you only have twenty-four hours in a day. It's harder still to realize that others only have twenty-four hours in their days.
Go gentle on Nelson, he's gracious to a fault, but human, hence limited to mortal time.
If you have ideas, try a few yourself before springing too many of them on others. It'll help both you and Nelson.
I still blush about the time I sent a really idiotic circuit to Nelson. I had an excuse, in that I was on (doctor prescribed) drugs at the time, but it still bothers me. If I had waited until my head was clear, I would have seen the flaw in the circuit, myself.
Grey
Go gentle on Nelson, he's gracious to a fault, but human, hence limited to mortal time.
If you have ideas, try a few yourself before springing too many of them on others. It'll help both you and Nelson.
I still blush about the time I sent a really idiotic circuit to Nelson. I had an excuse, in that I was on (doctor prescribed) drugs at the time, but it still bothers me. If I had waited until my head was clear, I would have seen the flaw in the circuit, myself.
Grey
Banned
Joined 2002