Aleph J build guide for noobs

[6L6]

1) Of course.

2) You don’t need bigger. The ‘standard’ Firstwatt PSU uses (8) 15,000uF 25V capacitors. You are going to have at least double that because dual mono. More is not necessarily better in this situation.

These will do beautifully, have high ripple rating, are suitably sized both physically and capacitance, of at least enough voltage rating, competitively priced, and there are a suitable number in stock. https://www.mouser.com/ProductDetail/EPCOS-TDK/B41231A7189M000?qs=f4aWRLuQiuxmb9fSgWqBfQ==

 

[Zen Mod]

1. yup
2. more, the merrier; from 10mF to 33mF, snap-in, 25Vdc to 35Vdc, reputable brand (if in doubt, ask) ........ I believe CDE are in stock ; in case of 35Vdc caps- take care of max Dia allowed on pcb; I presume it is 35mm

 

[wildlabs]

Well that was FAST -- and from two of my favorite contributors! Ordering now and hoping to post some photos (if I gather the courage) in the next month or so. Thanks so much, sincerely,
David

 

[TungstenAudio]

Getting a second AS-3218 transformer is a good way to go.
There are a variety of capacitors that will work with the power supply PCBs. Look for 15,000 uF or 18,000 uF in 35V or 50V rating. Not 25V. Set your search for snap-in electrolytics with those parameters.

 

[wildlabs]

Thanks TungstenAudio -- you were the inspiration for going with the dual power supplies. Have to decide on the case -- but I'm thinking the 5U 400 so I've got some elbow room. Like I said, this will be my tombstone.

 

[wildlabs]

I think I have everything together except for some of the connectors which I can substitute -- but this capacitor is not in stock at Mouser and I can't find at DigiKey:

https://www.mouser.com/ProductDetail/505-MKP20.1-100-5
Would either of these work? (they look very similar, but I'm getting a little dizzy with this order form)

https://www.mouser.com/ProductDetail/WIMA/MKP2D031001F00JO00?qs=sJjjjplDs9uI93%2B9VxfPzA==
https://www.mouser.com/ProductDetail/WIMA/MKP2D031001F00JI00?qs=sJjjjplDs9u1SRmPcC2duw==
thanks for your help.

David

 

[TungstenAudio]

Either of those may work. The only difference is the packaging. Check the dimensions to see if they will fit next to the 220 uF electrolytics.

 

[wildlabs]

Thanks again -- the dimensions are all the same.

David

 

[6L6]

The bypass caps are not necessary. You can omit them with no guilt. None of the factory Aleph had them…

 

[wildlabs]

Thanks 6L6

 

[Mulburg]

Is there any other way to find out when the boards will be available again? I’m on the email me list.

 

[getgoin]

I have just about everything for Aleph J build except the PCBs and PSU C9 (Safety Capacitors 3300pF 20% X1 760VAC/Y1 500VAC). Neither Mouser or Digikey has them. Being new to this I couldn't tell what "similar products" were similar enough. For sure the voltage ratings were different. Anyone know of an available substitute?

 

[Ben Mah]

https://www.mouser.com/ProductDetai...EpiMZZMsh%2B1woXyUXj8%2BfClNFq2LSarOIyj8Yk9s=

 

[getgoin]

Thanks Ben Mah. They're in my Mouser cart now.

 

[JeyDee]

Will the input wires really be able to handle all of the expected low level input power???

👻
🙃
🧐
🤪

 

[Zen Mod]

fat solid core there ....... I mean - anywhere ....... I have no complaint if you're sure what you're doing , for everything

though, you know who's Cojones you'll start chewing, if something goes wrong , and you need to remove pcb from heatsink



(been there, done that)

 

[JeyDee]

fat solid core there ....... I mean - anywhere ....... I have no complaint if you're sure what you're doing , for everything

though, you know who's Cojones you'll start chewing, if something goes wrong , and you need to remove pcb from heatsink



(been there, done that)

🙂 Yea, you are right about that aspect of tight and as short as possible solid core wiring. Well, i am reasonably sure i have got it right. But of course not yet absolutely suresure 🤫

So, i am thinking - i will desolder at the terminals, to get the boards out of the amps, if i got something really wrong. Or if there will be some modding down the road 🙂

 

[JeyDee]

Since i am planning to run the two stock, stereo Aleph J amplifiers i am building in parallel mono, i have been thinking lately:

Is i advisable to add output coupling caps, to each output channel, as in the ACA, to successfully run Aleph J:s in parallel mono? Or is it Possible/Advisable to simply adjust the output DC balance to near perfection - and then parallel them channels 2 and two?

I am planning to place and order for the PSU snubbers pretty soon, and thats also a good time for placing an order for the output caps. If i need them.

 

[mkane77g]

Thats some fat input wire

 

[TungstenAudio]

Well, this is the noob forum..
There is another forum for Aleph 30 & Aleph 60. Those are bigger amps with more output devices per channel. What we see there is more applicable to what you would like to do. Also look for Bablefish J by Zen Mod. That amp has options for adding extra output devices. You don't need to double the whole board set, just the output parts to some extent. Those output devices are all that need to be matched.
No output coupling caps are necessary.