Getting ready to start my first Pass build. I’ve done a lot of reading and as I’m still a rookie at electronics, I’m looking for verification. My primary speakers are Altec 605a’s, they are around 100db at 1 watt and 16 ohm, is the aleph a good match? Maybe I’d be just as well served with an ACA? I have an Antek 18-0-18 400va on the way as that seems to be compatible with several of the Pass builds.
The Aleph J is a fantastic match for your speakers! Probably the best choice out of the entire series.
Lol,if I could afford it I’d build them all! This hobby is quickly turning into an addiction. Thanks for the quick responses. I’m afraid it will have to be one or the other, at least till next year probably. I have decent soldering skills and have done a couple recapping jobs and just populated new boards on an old hafler dh-200. I’m really wanting to try out a class A design though. I’m leaning towards the aleph, does it do anything the aca doesn’t? I think if I do the aca I’ll just wonder what I’m missing with the aleph....
Build one a year.
My parents pay way more than that in Golf membership fees. That's before they even play one game of golf.
My parents pay way more than that in Golf membership fees. That's before they even play one game of golf.
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The ACA is a great, and safe, way to see how you like DIY audio. I got the full kit a few years ago, when I started. My speakers are ZuAudio high sensitivity full range speakers. They sounded great with the ACA.
They sound even better with the DIY Aleph J that I built next. VFet monoblock amps in production. It is a slippery slope...
They sound even better with the DIY Aleph J that I built next. VFet monoblock amps in production. It is a slippery slope...
A couple of quick questions if I may. I have a power supply of -24v/+24v. Is this sufficient or should I go after more voltage? And, can I mount this on a piece of wood to get it up and running or will I run into grounding problems. I have the boards and matched J74's. My speakers are open baffles. thanks
That PSU is fine if of sufficient current. More voltage will be detrimental.
Yes, you may bread board it, but remember that the Mosfets must be adequately heatsinked. Alephs run hot!
It's a great amp, you'll love it. 😀
Yes, you may bread board it, but remember that the Mosfets must be adequately heatsinked. Alephs run hot!
It's a great amp, you'll love it. 😀
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Welcome to the club. We have cookies. 😀
If your choice is between the ACA and the Aleph J, there's no comparison in my opinion. Build the Aleph J. If for no other reason than power. The ACA is a wonderful amp, but it's still just a couple of watts. The Aleph is 25w, and sounds much, much bigger than that as it clips so incredibly gracefully. It's also my favorite FW amp. Nelson also says it's the best sounding of the entire Aleph series, and I'm inclined to agree.
PCB
Is the Aleph J pcb still the same as this? I plan to do my own PCB. I have not expert into this but if this is the pcb then I have no problem to make it.
Or anyone could share the AJ pcb in pdf?
Is the Aleph J pcb still the same as this? I plan to do my own PCB. I have not expert into this but if this is the pcb then I have no problem to make it.
Or anyone could share the AJ pcb in pdf?
Aleph J with K170 and IRFP9240
Possibly a stupid question, but could the Aleph J circuit not be "inverted" to use 2SK170 for the input stage and IRFP9240 for the output?
Possibly a stupid question, but could the Aleph J circuit not be "inverted" to use 2SK170 for the input stage and IRFP9240 for the output?
Where? Not asking for specific links (you have better things to do than looking these up for me), but rather search terms that might get me there🙂
Hi Nic,
Found this in my hard drive, it might be what you have found..
It is a mini-aleph using N-jfet and P-mos output.
Have fun!!
Attachments
Firstly, it's going to get hotter. Watts is V x A, so increasing V will make more watts, an in the example of this amp, that's all going to be more heat in the heatsinks that needs to be dissipated.
Also you'll need bigger V rated capacitors, and at a certain point you'll burn up the Jfets.
Also you'll need bigger V rated capacitors, and at a certain point you'll burn up the Jfets.
Which way to go?
I have a 4U 400mm Dissipante chassis with stout dual mono +18v/-18v rails, and want to try it with a low voltage Aleph J build.
I have very efficient speakers and am not worried about maximum power output, but rather, how to get potentially the best sound out of the lower rail voltage.
Is it best to use all 4 output mosfets, or drop to one pair of outputs, ala Mini Aleph-J?
Thanks,
Matt
I have a 4U 400mm Dissipante chassis with stout dual mono +18v/-18v rails, and want to try it with a low voltage Aleph J build.
I have very efficient speakers and am not worried about maximum power output, but rather, how to get potentially the best sound out of the lower rail voltage.
Is it best to use all 4 output mosfets, or drop to one pair of outputs, ala Mini Aleph-J?
Thanks,
Matt