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DIY Purifi Amp builds

wineds

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Finally finished my build. A 5 to 12V compatible trigger allows me to turn everything on with my Okto Dac remote. Trigger is implemented using a SFH619A Darlington opto coupler which was wired inline and covered with heatshrink tubing and mesh. Thanks to @JimM for the ideas.

IMG_20200414_112029.jpg
 

phoenixdogfan

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I have decided to go forward with this project. I have sourced a local business (I live in Nashville, Tn) that does laser cutting of aluminum. The owner believes he can do a custom back panel from aluminum which will have all the proper cut outs and replace the back panel of the 300 mm wide Ghent Hypex NC400 case I purchased last year. Gonna cost around $125 USD. Only thing is it will be raw aluminum (no annodizing or powder coating). I can obviously anodizing at a later time, but it's expensive (like a $100 flat rate for annodizing). So my question is whether using an uncoated aluminum panel poses any safety risks, or is it perfectly OK, assuming I use Ghent's IEC grounding wire running to the case bottom?

Also, my second question is where can I get the wire housings for the end of the cables that connect to the Hypex Smsl 1200a400. Does either Hypex or Purifi supply them? Are the wires Purifi supplies pre-crimped or do I need to buy a crimping tool and crimps. If so, what size of crimps? Hyppex sells them but in two different sizes, so which size would I need to order? Also If neither Hypex nor Purifi supplies the wiring housing that snap connect into the SMPS what's my vendor for those? And what are the part numbers?

There are any number of good Youtube videos on how to crimp, so I'm pretty sure I could get the hang of it quickly, inasmuch as it seems very straightforward, but do the crimped wires just snap into the connector housing? Does that require any special technique?

I will keep everyone posted. Since my source will have a complete CAD design blueprint for the back panel perhaps he can become a resource to others on this site. He seems very professional and helpful. And who knows when Ghent will offer a case designed for Purifi. Seems like it's been promised since January. This could be a good way for people to go forward if they want to just do an assembly job, like me, rather than a customized full-on DIY.
 

JimM

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Aluminum would be fine, you could paint it you want color, look online for painting aluminum. There are no safety issues using bare aluminum vs anodize or painted. aluminum other than bare aluminum is more conductive.
JimM
 
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JimB

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I have decided to go forward with this project. So my question is whether using an uncoated aluminum panel poses any safety risks, or is it perfectly OK, assuming I use Ghent's IEC grounding wire running to the case bottom? ...

Really, just appearance. Just be sure you're happy to live with it.

... Also, my second question is where can I get the wire housings for the end of the cables that connect to the Hypex Smsl 1200a400. Does either Hypex or Purifi supply them? Are the wires Purifi supplies pre-crimped or do I need to buy a crimping tool and crimps. If so, what size of crimps? Hyppex sells them but in two different sizes, so which size would I need to order? Also If neither Hypex nor Purifi supplies the wiring housing that snap connect into the SMPS what's my vendor for those? And what are the part numbers? ...

In my opinion, this has been covered to death - probably far more than anyone wanted to see, back in this time-frame, where I gave options to achieve the wiring without soldering or crimping:
https://www.audiosciencereview.com/...y-purifi-amp-builds.10478/page-13#post-303183
https://www.audiosciencereview.com/...y-purifi-amp-builds.10478/page-24#post-329791
https://www.audiosciencereview.com/...y-purifi-amp-builds.10478/page-24#post-332770

Part numbers and sources have been covered.

... who knows when Ghent will offer a case designed for Purifi. Seems like it's been promised since January. This could be a good way for people to go forward if they want to just do an assembly job, like me, rather than a customized full-on DIY.
I'll follow up with Ghent to see how they are progressing. I was lead to believe it would be another couple months.
 
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mocenigo

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Aluminum would be fine, you could paint it you want color, look online for painting aluminum. There are no safety issues using bare aluminum vs anodize or painted. aluminum other than bare aluminum is more conductive.
JimM

Properly painting aluminium is however a chore. To get good results one should clean it very well with silicone remover, then use a etching primer or even better a 2K primer. Then wash again. Then paint it a few times. And it is easy to get it wrong. At least for me, I can be quite clumsy.
 

phoenixdogfan

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Properly painting aluminium is however a chore. To get good results one should clean it very well with silicone remover, then use a etching primer or even better a 2K primer. Then wash again. Then paint it a few times. And it is easy to get it wrong. At least for me, I can be quite clumsy.
I would probably either get it powder coated or annodized, but right now I just want to get it together and up and running, it is after all a back panel and will be in an equipment rack, so it may be so completely out of sight and mind, I might just decide there is no issue living with it indefinitely.
 

phoenixdogfan

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Really, just appearance. Just be sure you're happy to live with it.



In my opinion, this has been covered to death - far more than probably anyone wanted to see, back in this time-frame, where I gave options to achieve the wiring without soldering or crimping:
https://www.audiosciencereview.com/...y-purifi-amp-builds.10478/page-13#post-303183
https://www.audiosciencereview.com/...y-purifi-amp-builds.10478/page-24#post-329791
https://www.audiosciencereview.com/...y-purifi-amp-builds.10478/page-24#post-332770

Part numbers and sources have been covered.


I'll follow up with Ghent to see how they are progressing. I was lead to believe it would be another couple months.
Many thanks. I'll be up and running before Ghent even releases the new cabinet on that timetable, and he AFIK has shown no inclination to sell partial cases. So, speaking for myself, I'll give him a pass, and if he's delayed even longer than two months, my method may prove viable for anyone who wants a no frills way to get up an running with the Eval 1.

Many thanks for your help. This thread and you contributions have proven to be invaluable.
 
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JimB

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... and if he's delayed even longer than two months, my method may prove viable for anyone who wants a no frills way to get up an running with the Eval 1. ...
"Your" method still gets Ghent a sale, no?
 

phoenixdogfan

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"Your" method still gets Ghent a sale, no?
Yes it does, b/c anyone doing it will have to buy one of his cases and adapt the back end, so he should have no complaints esp if he's unwilling to send a modified back end. It just spares me, personally, the wait time and the expense of buying two cases--one which I'll never use and have to resell just to get back some of my money spent.
 

Labjr

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Is Ghent making a case for the EVAL1 set with the banana plug speaker outputs?
 

TimoJ

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Finally got the speaker connectors from China (they are actually really good quality, full metal). Removed the original banana terminals and the switch from the PCB. I also wired sense wires from the PCB to the speaker terminals.
Still waiting for power switch, not sure how to do all that. I maybe just switch AmpOn signal with the switch since I use an external relaybox to switch the main power.

Here are few pics of my amp's current status. (speaker terminal soldering joints are fully flowed with lots of solder and heat. For some reason picture reflections makes them look bad)

Pic1.jpgpic2.jpg
 

maxxevv

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I have decided to go forward with this project. I have sourced a local business (I live in Nashville, Tn) that does laser cutting of aluminum. The owner believes he can do a custom back panel from aluminum which will have all the proper cut outs and replace the back panel of the 300 mm wide Ghent Hypex NC400 case I purchased last year. Gonna cost around $125 USD. Only thing is it will be raw aluminum (no annodizing or powder coating). I can obviously anodizing at a later time, but it's expensive (like a $100 flat rate for annodizing). So my question is whether using an uncoated aluminum panel poses any safety risks, or is it perfectly OK, assuming I use Ghent's IEC grounding wire running to the case bottom?

.

Your local workshops are ripping you off big time for both things.

I would suggest you do a search online (wherever you may be located) for similar services. If you can create the required CAD files for the laser cutting, I'm very sure you can get it done for both process at about 1/5 to 1/4 of what you were quoted above.
 

kaka89

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The more I read the less confident I am to build this.
I thought it would be as easy as assembling a PC. It is not.

Especially when I want to build mine using two Neurochrome buffer boards and 1 SMPS1200A400, the default cable kit doesn't do that.
 
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JimB

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Is Ghent making a case for the EVAL1 set with the banana plug speaker outputs?
Kind of like @TimoJ? I hope so. I'll will ask about their project status after I prepare some test notes...
 

Labjr

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Kind of like @TimoJ? I hope so. I'll will ask about their project status after I prepare some test notes...
I think they'd have to make a case that requires the builder to remove the banana jacks from the PCB?
 
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