Finally my pearl3 is playing, thank you Wayhne, 6L6 and everyone involved in this great project.
@ Boydk Thanks for the Jfets and I don't miss my defective Xono, you were right.
The case and parts of the power supply are from my Xono.
@ Boydk Thanks for the Jfets and I don't miss my defective Xono, you were right.
The case and parts of the power supply are from my Xono.
Attachments
Hi,
especially for the Pearl 3 I finished my first ever XLR interconnect
3 x 1 m pure silver per signal path, a total of 9 m for a complete cable, braided, shielded per signal path, and then the three (+, -, and GND) braided again, with Viborg pure copper/gold-plated connectors. 16 hours of handcrafting 🙈
Pure fun 😍
especially for the Pearl 3 I finished my first ever XLR interconnect
3 x 1 m pure silver per signal path, a total of 9 m for a complete cable, braided, shielded per signal path, and then the three (+, -, and GND) braided again, with Viborg pure copper/gold-plated connectors. 16 hours of handcrafting 🙈
Pure fun 😍
Let's do a little math. 32V rails unloaded, 55mA per rail per board. Worst case is 32-15= 17V drop at the regs. P = IV = 17V * 55mA per reg = 0.935W So each reg/heatsink combo will dissipate about 1W. You'll want to look at the datasheet for: max input voltage, power dissipation. Can the reg take 32V in?
In reality the voltage drop will be a little less because loaded voltage will be a little less. But ~1W is close enough for this exercise.
An possible way to burn off some of those volts will be to do some prefiltering with one or more RC stages after your 4700uF caps. Do you have more caps in your parts stash? You'll want to pick some resistors to get a good voltage drop AND with a power rating to handle the heat they will burn off. For this calculation you need to consider 110mA through each resistor to account for both channels.
Perhaps a 1N5349B (zener diode, 5 watts, 12 volts) in series, one per rail, might be something to consider? (datasheet)
Today there are 37,000 of them in stock at Mouser US
Today there are 37,000 of them in stock at Mouser US
Thanks. I'm going to try a buck converter which takes up to 40v and has a pretty tiny footprint so will fit in the enclosure...
I wanted to read that article, written by some guy named Mark Johnson, and I was somewhat frustrated by the difficulty in gettin hold of it. Bought a print copy of that issue off Amazon. That's not a very cost effective method of getting access to the material. Glad to be pointed to the DIYAudio store. They have the entire archive on a thumb drive. I have ordered it, hope Jan Didden is getting a bigger slice of the money than he gets from Amazon sales.
I have a question regarding the Pearl 3 power supply pcb. If you elect to use a machine screw, star washer and nut for the chassis ground located in the corner of the pcb, is that screw passing through the chassis (presumably with the chassis finish removed)?
It must attach to the chassis somewhere.
Also, does Jim or anyone else have a recommendation for an inexpensive (less than $50) ferrule tool kit? There are so many conflicting reviews on Amazon and the internet.
Thanks,
John
It must attach to the chassis somewhere.
Also, does Jim or anyone else have a recommendation for an inexpensive (less than $50) ferrule tool kit? There are so many conflicting reviews on Amazon and the internet.
Thanks,
John
Ok, I see what the intention with that ground screw is: it must be tied to the chassis.
Would appreciate a recommendation on the ferrule tool.
John
Would appreciate a recommendation on the ferrule tool.
John
I use an inexpensive ferrule kit (crimping tool plus supplies) that I bought from Amazon HERE . I liked it so well that I had Amazon ship another kit to @6L6 , who liked it too. Probably there are highly regarded Name Brand crimpers for professional use, sold at higher prices, but I don't know about those.
We use This Phoenix Contact ferrule crimper at the lab. It does a similar job at 10x the price of the Amazon unit.
Getting closer, but still not finished:
Thanks!
I had great help, of course
she is just sleeping there 🙈
I had great help, of course
she is just sleeping there 🙈Thanks Mark. I was leaning toward the Preciva brand based on what I saw. In addition to Phoenix, Knipex and Wiha make pricey versions of the tool, but as a hobbyist that tool will only get occasional use.
John
@jiminassi Iwiss make reasonably-priced and quality crimping tools sold under the iCrimp brand.
The Icrimp qr-kit does ferrules, and various other fittings. It's available on Amazon, one of my rare purchases from them. Sorry appears to be NLA.
They have a ferrule crimper.
Matt's Tech Pages has a good section on crimpers: https://www.mattmillman.com/info/crimpconnectors/
The Icrimp qr-kit does ferrules, and various other fittings. It's available on Amazon, one of my rare purchases from them. Sorry appears to be NLA.
They have a ferrule crimper.
Matt's Tech Pages has a good section on crimpers: https://www.mattmillman.com/info/crimpconnectors/
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Guys, I have the Wirefy Crimping tool with several die sets for different types of crimp terminals including ferrules which I can recommend (although it is relatively expensive). I use it on every build. But the tool specifically made for ferrules, as you know, has a completely different operating mechanism that is specifically designed to crimp those round barrels. I decided on the latest designed Preciva tool which will crimp down to AWG 28 ferrules. $18.99 on Amazon with something like 1200 ferrules as a kit.
John
John
Maybe a crimping tool thread on its own would be in order, so "we" can
get back to, what it´s all about: Pearl-3??
Following a thread and getting one notification after another on totally P-3-unrelated stuff is kind of PITA.
get back to, what it´s all about: Pearl-3??
Following a thread and getting one notification after another on totally P-3-unrelated stuff is kind of PITA.
