Hi guys,
I'm planning on building the Noir and I have a few questions.
Please don't shoot me if I ask 'stupid' questions. I'm a bit ignorant about things electrical and rather be safe then sorry.
"The DC wall wart output is filtered by a common mode choke and applied to a bridge rectifier. This means Noir can accept both (positive center, negative sleeve) wall warts and also (negative center, positive sleeve) wall warts"
Does this mean A* and B* can both be plus or minus? (I guess so, but just to make sure).
About the power supply, are there any special requirements, or can I take any 24 volt, > 750 ma wall wart?
I noticed the one in the BOM is out of stock for quite some time now, and I think I may have some lying around somewhere (1.5 and 4 amps).
I'm planning on building the Noir and I have a few questions.
Please don't shoot me if I ask 'stupid' questions. I'm a bit ignorant about things electrical and rather be safe then sorry.
"The DC wall wart output is filtered by a common mode choke and applied to a bridge rectifier. This means Noir can accept both (positive center, negative sleeve) wall warts and also (negative center, positive sleeve) wall warts"
Does this mean A* and B* can both be plus or minus? (I guess so, but just to make sure).
About the power supply, are there any special requirements, or can I take any 24 volt, > 750 ma wall wart?
I noticed the one in the BOM is out of stock for quite some time now, and I think I may have some lying around somewhere (1.5 and 4 amps).
PSU
Hi jtrompetter
Like you I am a novice too, so I am not sure how tollerant the Noir circuit is of different DC polarity connections at the socket.
Maybe Mark can weigh in on that question.
Because this is a high qality hi fi project I would suggest you pay a little more for you PSU you could also add the diyaudiostore SMPS filter.
Supplies with 24 volt DC output and rated greater than 500ma should be fine.
The wallwart type is safest for a novice, just make sure it has your contries mains connector plug.
You could try Digikey, Mouser, or even RS components.
Have fun.
Hi jtrompetter
Like you I am a novice too, so I am not sure how tollerant the Noir circuit is of different DC polarity connections at the socket.
Maybe Mark can weigh in on that question.
Because this is a high qality hi fi project I would suggest you pay a little more for you PSU you could also add the diyaudiostore SMPS filter.
Supplies with 24 volt DC output and rated greater than 500ma should be fine.
The wallwart type is safest for a novice, just make sure it has your contries mains connector plug.
You could try Digikey, Mouser, or even RS components.
Have fun.
Mouser's website is offline at the moment, but I was able to find a suitable 24V DC wall wart at Netherlands DigiKey: (link). Images below. Maybe a more thorough search would turn up another one, rated for 500 mA {this one is 1000 mA -- okay but unnecessarily overpowered}
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Attachments
Completed my Noir HPA
This was another great project form DIY Audio Store,
I like the black PCB, makes all the component pop. Cleaning black PCB seam a bit harder as you see any residue that is left behind. I still have a few final touches, I tried (3) different products but ended up with Isopropyl Alcohol and paper towel to get it clean. Lay paper towel strip on the PCB and use a brush or Q-Tip with Alcohol and rub it on top of the paper towel, it will pull the flux residue into the paper when the alcohol vaporizes. Almost bought a ultra sonic cleaner but didn't in the end, maybe future purchase.
The Build went smooth, the full kit was not in stock, so I sourced the parts between Mouser, Digi-Key, Parts Connexion & Parts Express. It a bit of a treasure hunt find all the parts you need for a project these days, but adapt and overcome.
Startup went well; followed the build guide, and dialed back all (3) pots. after applying power the Bias started at 2.5V and raised to 5.10V. Small tweak after warm up and all was stable. No His or Hum, played some of my go to tunes on my powered speakers to do a quick test if audio works, the Noir sound great but need to spend some more time with it and try my headphones over the weekend.
Next Project will be the Aleph J Dual Mono, cant wait. I have received all the parts, but still have to order the enclosure. Planning to start mid December during my 2 weeks vacation. (if I can wait that long
)
I have to start thinking about speaker selection, I'm building a power amp but don't have a pair of passive speakers (No Bueno, as we say in Miami)
I hope that everybody has a great weekend,
Greetings form Sunny Miami,
Max
This was another great project form DIY Audio Store,
I like the black PCB, makes all the component pop. Cleaning black PCB seam a bit harder as you see any residue that is left behind. I still have a few final touches, I tried (3) different products but ended up with Isopropyl Alcohol and paper towel to get it clean. Lay paper towel strip on the PCB and use a brush or Q-Tip with Alcohol and rub it on top of the paper towel, it will pull the flux residue into the paper when the alcohol vaporizes. Almost bought a ultra sonic cleaner but didn't in the end, maybe future purchase.
The Build went smooth, the full kit was not in stock, so I sourced the parts between Mouser, Digi-Key, Parts Connexion & Parts Express. It a bit of a treasure hunt find all the parts you need for a project these days, but adapt and overcome.
Startup went well; followed the build guide, and dialed back all (3) pots. after applying power the Bias started at 2.5V and raised to 5.10V. Small tweak after warm up and all was stable. No His or Hum, played some of my go to tunes on my powered speakers to do a quick test if audio works, the Noir sound great but need to spend some more time with it and try my headphones over the weekend.
Next Project will be the Aleph J Dual Mono, cant wait. I have received all the parts, but still have to order the enclosure. Planning to start mid December during my 2 weeks vacation. (if I can wait that long
)I have to start thinking about speaker selection, I'm building a power amp but don't have a pair of passive speakers (No Bueno, as we say in Miami)
I hope that everybody has a great weekend,
Greetings form Sunny Miami,
Max
Attachments
First a thank you to the designer and the community.
My DAC (MiniDSP IL-DSP) has too little power for my new headphones (AKG-K701). Therefore, I have now come across the Noir, which I am considering building. In the scheme it has an ALPS 10K potentiometer. I have a 100K ALPS. Since 10K is a lot less load than headphones anyway, can I use 100K right away? Or should I use a 1k potentiometer as a source for a headphone output anyway?
I thank you for your opinion.
Felix
My DAC (MiniDSP IL-DSP) has too little power for my new headphones (AKG-K701). Therefore, I have now come across the Noir, which I am considering building. In the scheme it has an ALPS 10K potentiometer. I have a 100K ALPS. Since 10K is a lot less load than headphones anyway, can I use 100K right away? Or should I use a 1k potentiometer as a source for a headphone output anyway?
I thank you for your opinion.
Felix
Higher resistance potentiometers generate more thermal noise. That's why I recommend 20K or below. However, if you want to try 100K in your Noir and find out whether the noise level is acceptable to you -- please go right ahead. The pot is connected to the PCB by fly-wires, so it definitely isn't major surgery to remove the volume control and install another in its place.
The entire electronics industry is experiencing a supply shortage, everywhere around the world, in all product categories. Demand exceeds supply, and it takes years to build more factories to increase supply. Semiconductors get most of the press coverage, but ALL electronic components are in short supply at the moment. Even humble passives like resistors and inductors.
I notice that DigiKey does have, in stock, the big brother of Noir's L1. Noir calls for a 3.4 millihenry, 500 milliampere choke from Kemet's SU9V product line. At a small penalty in noise filtering, you could substitute the next-higher current model: 700 milliamps and only 1.7 millihenries. Same manufacturer, same physical dimensions, fits in the same PCB footprint. Prefix "SU9V" where V indicates Vertical. But current rating is a little bigger than necessary and inductance is a little smaller than desired. (I also notice that Mouser doesn't have that one in stock).
https://hbr.org/2021/02/why-were-in-the-midst-of-a-global-semiconductor-shortage
https://techwireasia.com/2021/10/heres-what-the-2021-global-semiconductor-shortage-is-all-about/
https://en.wikipedia.org/wiki/2020–2021_global_chip_shortage
I notice that DigiKey does have, in stock, the big brother of Noir's L1. Noir calls for a 3.4 millihenry, 500 milliampere choke from Kemet's SU9V product line. At a small penalty in noise filtering, you could substitute the next-higher current model: 700 milliamps and only 1.7 millihenries. Same manufacturer, same physical dimensions, fits in the same PCB footprint. Prefix "SU9V" where V indicates Vertical. But current rating is a little bigger than necessary and inductance is a little smaller than desired. (I also notice that Mouser doesn't have that one in stock).
https://hbr.org/2021/02/why-were-in-the-midst-of-a-global-semiconductor-shortage
https://techwireasia.com/2021/10/heres-what-the-2021-global-semiconductor-shortage-is-all-about/
https://en.wikipedia.org/wiki/2020–2021_global_chip_shortage
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