hey all any thoughts on sources for the torroid for this? The places I’ve looked did not have 18v secondaries at the va level the thread start recommends
Is there any value or harm in going with a higher voltage? If going higher is ok what kind of range is ok? Are there advantages or disadvantages with higher volt or should i just stick with 18?
Would this be ok? https://www.amplifiedparts.com/products/transformer-hammond-toroidal-power-18v-36v-secondary i don’t think it has the same va rating i thought the original said closer to 300va?
Curious what folks use for the power supply side. I tried and failed to understand the wiring for the board linked. It seems like the original post they used a separate rectifier than the power supply board has?
I still have a few of the boards but no posts to put in there. That’s easy enough to order though 😉
Is there any value or harm in going with a higher voltage? If going higher is ok what kind of range is ok? Are there advantages or disadvantages with higher volt or should i just stick with 18?
Would this be ok? https://www.amplifiedparts.com/products/transformer-hammond-toroidal-power-18v-36v-secondary i don’t think it has the same va rating i thought the original said closer to 300va?
Curious what folks use for the power supply side. I tried and failed to understand the wiring for the board linked. It seems like the original post they used a separate rectifier than the power supply board has?
I still have a few of the boards but no posts to put in there. That’s easy enough to order though 😉
The TE connectivity datasheet says the tolerance is +/-5% +0.1R
In this case, the additional 0.1 is enough to get it to the measured value.
Regardless, use them, don't worry about it, the amp is going to sound and work perfectly. 🙂
In this case, the additional 0.1 is enough to get it to the measured value.
Regardless, use them, don't worry about it, the amp is going to sound and work perfectly. 🙂
The highest-rated model on the sheet you linked appears to be 225VA which would be too low, I think. The recommendation is for 300VA - 400VA
I’m a fair way into the thread and 20V secondaries seem to be used successfully but you might need heat sinking to be a bit larger to dissipate the extra heat, if I understand correctly.
There’s lots of info in this thread on using the diyaudio store universal PSU (which I’m doing) and lots of recommendations for suitable transformers. It might help to mention what part of the world you’re in for more specific endorsements
@bilsch the 225VA Hammond you found is just a little too small. I wouldn't suggest less than 250VA.
You can go as high as 20VAC secondaries, but make sure you use 35v minimum caps everywhere.
https://www.newark.com/vigortronix/vtx-146-300-218/300va-toroidal-transformer-2x18v/dp/44AC7814
https://www.parts-express.com/Avel-Y236651-250VA-18V18V-Toroidal-Transformer-122-620?quantity=1
PN 732.182 from Toroid would do nicely. 320VA 18+18 https://toroid.com/power-supply-transformers-toroidal/
What's your question about the PSU? I don't follow what you are asking...
You can go as high as 20VAC secondaries, but make sure you use 35v minimum caps everywhere.
https://www.newark.com/vigortronix/vtx-146-300-218/300va-toroidal-transformer-2x18v/dp/44AC7814
https://www.parts-express.com/Avel-Y236651-250VA-18V18V-Toroidal-Transformer-122-620?quantity=1
PN 732.182 from Toroid would do nicely. 320VA 18+18 https://toroid.com/power-supply-transformers-toroidal/
What's your question about the PSU? I don't follow what you are asking...
Thanks for the links in the different torroids. I was actually thinking that with the space it may be easier to just get 2 smaller torroids and feed them from the same ac line. Would that work? Of course that means each channel needs it’s own rectifier and cap board. Maybe dual like that is better?
My question on the rectifier board from the shop is how to wire it up correctly. I just don’t understand what each of the terminals is and how to hook up the secondaries. Maybe I’m missing something obvious? I think some of the images in the first few posts are just gone now too.
What i would love to see is a compendium of sorts. With information spread out in super long threads it makes digestion difficult - at least for me. Happy to contribute in any way i can i just dont have a lot of knowledge yet. Going through 508 pages of text on an amplifier is a fairly tall order for proper assembly
I would love to see a step by step doc on the wiring for the psu. Explain the transformers to use or at least what qualities and maybe geographical sources? Explain what each terminal label actually means and which ones to use for their intended purpose
Similar for the different amplifier boards. I know some have this level of detail and some just link to a thread
My question on the rectifier board from the shop is how to wire it up correctly. I just don’t understand what each of the terminals is and how to hook up the secondaries. Maybe I’m missing something obvious? I think some of the images in the first few posts are just gone now too.
What i would love to see is a compendium of sorts. With information spread out in super long threads it makes digestion difficult - at least for me. Happy to contribute in any way i can i just dont have a lot of knowledge yet. Going through 508 pages of text on an amplifier is a fairly tall order for proper assembly
I would love to see a step by step doc on the wiring for the psu. Explain the transformers to use or at least what qualities and maybe geographical sources? Explain what each terminal label actually means and which ones to use for their intended purpose
Similar for the different amplifier boards. I know some have this level of detail and some just link to a thread
There's some great info in @rhthatcher documents he made for his PSU designs. I found them very helpful in trying to wrap my mind around the PSU wiring. Note that his stereo boards integrate the soft start thermisters into the PSU board as well as the thermister inserted in series for the PSU chassis ground, which are separate off board connections one makes on most other PSU builds. Look at his "F5 New Orig Build Guide-1.0b.pdf", the W8 doc, and V8 doc to put some of the puzzle pieces together.
There's also a great video from BAF'24 that @6L6 presented on linesr PSU builds.
There's also a great video from BAF'24 that @6L6 presented on linesr PSU builds.
Yes, thats a lot. But you will for sure learn a hell of a lot. It is absolutely worth it. I read the whole thing when i was a brand new Aleph J builder. And I can really recommend it! 🙂
Take it easy, do Not hurry. Simply Enjoy the ride.
🎷🙂🎸
You have two secondaries (4 wires total) with Antek transformers. They are AC output of course and you need one rectifier for each secondary. I recommend you look at the datasheet for the specific rectifier you have to know which pins/tabs are for the two AC wires from transformer secondary vs which are your rectified DC positive & negative out to the CRC filter board.
Heres an example showing blue/green Antek secondaries going into the rectifier, with red/black DC rectified coming out and going to CRC PCB. Note the purple PCB on top of the rectifier is Randy's snubber PCB.
RankStranger - As Ben has said, you would need a better meter to accurately measure resistors of low value. I have an HP 34401A that can do a 4-wire Kelvin measurement for resistance. Otherwise you are just measuring the resistance of the meter leads also, in addition to your resistor. I'm sure your resistors are fine.
bilsch, there is also an Aleph J build guide for noobs, I referred to that thread as well. The first post has tabs for each step in build process.
Not at all! Sorry if you took it that way.
I was hoping to learn WHY that is the best way to do it.
--What is the little tab thingie and why ground it (something about a ground for a shielded cable?)
--Anything I should be aware of connecting it the way you suggest? Any fringe case I would need to consider compatibility wise? Mostly thinking about using it with a true balanced XLR preamp vs. just a XLR cable carrying a standard unbalanced signal. I know the Aleph J is not a balanced amp.
--Even if not ideal...if I only hook up pins 2 & 3 (+ / -), it would still work. What I am doing here is making sure the other stuff is grounded, which is best practice(?)
@birdbox where did you get the rectifier pcbs? Is there a project with the schematic / board files or did you just order them from somewhere?
From the photo it looks like you are using the capacitor side of the diyaudio power supply board - just not the rectifier side?
@roboDNA posted free gerbers and you can have a PCB house fab up 15-30 for around $10 shipped. PM me if you need a little guidance.
The boards you see in the photo are sold by @rhthatcher. I had to drill out the center hold in the PCB though to get the bolt head through. I belive roboDNA's design has a larger general hole to accommodate bolt heads to pass through to the rectifier base (don't want to load up the fiberglass PCB as that can lead to problems.)
The boards you see in the photo are sold by @rhthatcher. I had to drill out the center hold in the PCB though to get the bolt head through. I belive roboDNA's design has a larger general hole to accommodate bolt heads to pass through to the rectifier base (don't want to load up the fiberglass PCB as that can lead to problems.)
@6L6 see below!
The main preamp driving it will be a McIntosh C53, which is balanced on the XLRs (though there is conveniently unbalanced RCA pre-outs as well I can use). I also want to use this amp with other preamps that will have unbalanced/RCA connectors. So...ideally trying to do the most universal option that will work with everything, even if I compromise a bit on performance.
Another solution is I can just ditch the XLR inputs entirely and use RCA inputs on the build.
Thanks!
The main preamp driving it will be a McIntosh C53, which is balanced on the XLRs (though there is conveniently unbalanced RCA pre-outs as well I can use). I also want to use this amp with other preamps that will have unbalanced/RCA connectors. So...ideally trying to do the most universal option that will work with everything, even if I compromise a bit on performance.
Another solution is I can just ditch the XLR inputs entirely and use RCA inputs on the build.
Thanks!