You don't want a 160VA, all it will do is radiate more hum. If you are buying new, get around 50VA.
Not finding anything on the SKA GBS50. What is it?
(24) 4700uf caps? That's enough for a really, really big power amp.
Wayne would approve - look at an inside photo of any of the XP phonostages. TONS of capacitance.
Not finding anything on the SKA GBS50. What is it?
(24) 4700uf caps? That's enough for a really, really big power amp.
Wayne would approve - look at an inside photo of any of the XP phonostages. TONS of capacitance.
Hi All
This is may 1st post on the Pearl 2 forum. Have read through it a few times it is incredible the amount of info that their is. To a 1st timer this amount of info can add to confusion, so when that happens I will ask questions. I am building the Pearl 2 with the diyaudio PSU. I have ordered all the parts (I think).
My toroidal is 50vac 2x22vac
Nichicon 10 000uf 35v.
Will the above capacitors be adequate for both the Pearl 2 and the PSU?
This is may 1st post on the Pearl 2 forum. Have read through it a few times it is incredible the amount of info that their is. To a 1st timer this amount of info can add to confusion, so when that happens I will ask questions. I am building the Pearl 2 with the diyaudio PSU. I have ordered all the parts (I think).
My toroidal is 50vac 2x22vac
Nichicon 10 000uf 35v.
Will the above capacitors be adequate for both the Pearl 2 and the PSU?
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This may be a little late by way of answer, but still ...
The 22V secondary x 1.4 gives approx 31V, but since the trafo is only about 15% loaded, we should add 10% regulation factor, giving you about 34V. Then rectifier diode loss drop ~1V puts you somewhere in the neighborhood of 33V at the capacitors.
So, technically, 35V caps will work but it only leaves a small margin for “oops”. I’d suggest 50V rated caps. It’s what I’m using, but I’m also using a trafo with 24V secondaries.
Terry
once it's gone through PC , it's in CAD category
even if only for pic posting purposes
I started out firing up DipTrace intending to get a pcb fabricated, then quickly came to my senses, realizing for a small simple one-off CLC power supply that there was a cheaper faster easier way.
This is certainly more complex than the method I used - I just poked the components through the empty board until they fit well next to one another. No need to use so much "fancy technology."
I had leftover perfboard scraps, and wasn’t sure they were quite big enough to fit the whole supply circuit as I had it designed. Good thing I checked, because the rectifier diodes and 10mF caps were indeed too big if I wanted to keep the inductors for the CLC, so I had to change to DO-41 diodes and caps with a slightly smaller diameter. Sadly by the time I went through the layout iterations and part changes, it probably would have been faster to do the pcb.
I know you get great success with separate boxes for power supply and the Pearl 2 in terms of quietness but frankly it is a lot of expense/weight/space for just phono. I have been using Antek transformers with the available optional thick metal shielding with great success. I have used these with my Ba3 preamp and my Burning amp (available up to 600 VA) and I have to put my ear to the speaker to hear any hiss at all on phono input with volume at max. This is even with unit modified for 55 db of gain. I can't hear hiss 3 inches from speaker. I call that pretty quiet from all 3 components.
I like to keep my power supplies very simple. For the pearl I used simple CRCRCR and have pretty low ripple. The board regulates it again so no need for complex circuits. I do filter my AC power supply with RFI filter
I like to keep my power supplies very simple. For the pearl I used simple CRCRCR and have pretty low ripple. The board regulates it again so no need for complex circuits. I do filter my AC power supply with RFI filter
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Eric, No doubt the Pearl 2 is dead quiet with an external power supply but it may interest you to know several builders have built the Pearl 2 with the powers supply in a single chassis. I have personally built two Pearl 2s, both are single steel chassis construction. They are dead quiet. The Antec toroidal transformers are in cans in both units, which curiously, the cans cost more than the transformer itself. The AC wiring is twisted and away from the input. One of my Pearl 2s has braided shielding on the input and output wires and one doesn’t, and there is no difference in sound or musicality. Also one has 50v rated components, the other 35v rated components, again no difference. I’ve tried out several phono stages over the years, the Pearl 2 is hands down the most beautiful sounding to my ears.
As my equipment rack is getting full, I'm contemplating moving my Pearl PSU inside the chassis with the PCBs. I was planning on using a small transformer and a pair of Salas' BiB regulators. If this works, I get a shelf back to use for a new piece of equipment
Dont know the particulars of your build, I sort of followed 6L6's lead. If my power supply gets too near the Phono section chassis, it hummed. Seems like I remember 6L6 having same issue.
Interested to see how you tame this issue!
Russellc
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Jim: yes, the plan is to use Salas' shunt reg in place of the onboard regulators for the Pearl II. I have a few sets of boards, one of which is partially populated. Need to acquire the appropriate transformer first. I was thinking of using Antek's smallest toroid.
Russellc: I used Jim's example as well. But box space is getting sparse, so something has to give. Not sure how this will turn out, but it will be a little while before I actually get to try this. I'm really hoping I can make this work - I know a few others have. I have an Aleph-J (for me) and an ACA to build with my 11 year old daughter for her birthday first...
Russellc: I used Jim's example as well. But box space is getting sparse, so something has to give. Not sure how this will turn out, but it will be a little while before I actually get to try this. I'm really hoping I can make this work - I know a few others have. I have an Aleph-J (for me) and an ACA to build with my 11 year old daughter for her birthday first...
Hello everyone,
I have a question regarding a PSU for Pearl II. Do you think it would be possible to build this using something off the shelf like a Mean Well PSU GST120A48-P1M https://cdn.shopify.com/s/files/1/1006/5046/files/GST120A-spec.pdf? The reason I ask is that this would be my first build after ACA 1.6 and I would like to avoid handling high voltage circuits as my immediate next project.
By the way, thanks for all your discussions and pictures, I think I found a new hobby that will burn a hole in my pockets
I have a question regarding a PSU for Pearl II. Do you think it would be possible to build this using something off the shelf like a Mean Well PSU GST120A48-P1M https://cdn.shopify.com/s/files/1/1006/5046/files/GST120A-spec.pdf? The reason I ask is that this would be my first build after ACA 1.6 and I would like to avoid handling high voltage circuits as my immediate next project.
By the way, thanks for all your discussions and pictures, I think I found a new hobby that will burn a hole in my pockets