Thank you.
I think they are the same as the dimensions of the Galaxy case given on the store chassis page but it would be good to have this confirmed.
I have a Metec case which is very close in width and height but is conveniently deeper so I can fit an infra red remote controlled Alps blue pot which I'll use and also add a second pair of RCA sockets with a DPDT toggle switch.
I think they are the same as the dimensions of the Galaxy case given on the store chassis page but it would be good to have this confirmed.
I have a Metec case which is very close in width and height but is conveniently deeper so I can fit an infra red remote controlled Alps blue pot which I'll use and also add a second pair of RCA sockets with a DPDT toggle switch.
@batteryman
Main pcb, 182x112
Front/back pcb 43x232
Face mounting holes 25x220 (equally located off center lines)
Main pcb, 182x112
Front/back pcb 43x232
Face mounting holes 25x220 (equally located off center lines)
Building out my Noir today, stuffing the what is supposed to be PNP bc516 (Q21/Q71) transistor, threw it in the tester just to make sure the pinout is correct and the mega328 is telling me it in a NPN. Part numbers match the circuit, even says jcbc516 on it. Is the tester wonky? First time using this tester.
Well, confirmed it is a PNP and the tester is being strange. DMM confirms it. Still learning this stuff.
The Mega328's firmware isn't sophisticated enough to recognize Darlington bipolar transistors. Probably its creators ran out of memory on the dirt cheap microcontroller, and didn't write code for anything except the most common devices. It doesn't recognize silicon controlled rectifiers either. Or Diacs. Or polyfuses. Or high-transconductance JFETs.
Just fired it up and letting it stabilize now! I mounted the power switch upside down so gotta flip that over, will have to go back through and shorten up all the fly wires too. Haven't put any music through it yet, thats next!
My pcbs arrived a few days ago & the parts on the BOM from Mouser arrivved last week so ready to go.
I accidentally bought two sets of pcbs so if anyone in the UK wants a set at cost price with free postage please pm me.
I'll post photos showing my build with remote volume control and 24v linear psu which arrived last week as well. Also some testing using REW.
I accidentally bought two sets of pcbs so if anyone in the UK wants a set at cost price with free postage please pm me.
I'll post photos showing my build with remote volume control and 24v linear psu which arrived last week as well. Also some testing using REW.
Did a quick test with music, got a hum that changes with volume and right channel is about half the output of left. Did the initial wire wiggle test and nothing changed. Will pull it apart and go back through it. Input was from my phone playing Spotify, and used some cheap akg ear buds for initial test.
Any thoughts on where I should start looking on the right channel?
Any thoughts on where I should start looking on the right channel?
Nice I have build headphone amps using TubeCad Circuits before, Especially his SRRP designs. This is his version of a "Better" Solid state version of SRRP:
https://www.tubecad.com/2005/February/blog0037.htm
And this is the amp I build based on that circuit:
And a prototype (not the final version).
https://www.tubecad.com/2005/February/blog0037.htm
And this is the amp I build based on that circuit:
And a prototype (not the final version).
I was attracted to the Noir because I am tired of opamps and prefer simple designs and tube amps & preamps.
We have become far too obsessed with the specs and trying to achieve almost unmeasureable distortion levels, as if either will guarantee better sound quality.
We have become far too obsessed with the specs and trying to achieve almost unmeasureable distortion levels, as if either will guarantee better sound quality.
Same here. I have a nice-ish commercial opamp based hpa (Schiit magni heresy), a hybrid tube (SS design) and now this. Still have to debug my noir this week, figure out the low volume on the right channel and the hum.
At least you'll get much satisfaction from solving the problems and I can only hope to avoid them!
Had a little time after dinner tonight to sit at the bench with the noir and methodically work through the issues, hum and R-channel is half the volume.
With electronics I tend to point the finger in the mirror as the root of all problems, so I was sure I fumbled something, but took a step back and decided to eliminate things 1 by 1.
Shorted input, and I had to flip the switch a couple times to make sure it was on! Ok, that's good! Tried my lab headphones (cheap akg ear buds) directly into my phone (Samsung Galaxy S9+) and would you guess what I heard? Yep, right channel at half volume, lol!
I grab my Salnote Zero iem (32ohm) and plug those into my phone, equal volume and expected sound quality. Ok, phone isn't shot. Plug into Noir, BOOM both channels at equal volume! Yes! Problem #1 "fixed" by replacing faulty test equipment.
Now for the hum. I disconnect the 3.5-RCA splitter from my phone and the hum is still there and acting like RF interference, as I move it around I can hear it changing. Wiggle the super extra long fly wires and yep, it changes too. Not much, but you can hear it.
I grab my Kindle Fire 7 to try a different source and instantly when I plug the splitter cord in it goes dead silent!
WooHoo! And DAMN this thing sounds good! Boy, what a relief it is to know I actually got it right the first time and just had faulty test equipment! Quiet, is an understatement! This thing is black. Like no moon, underground in a cave. Can't hear a thing and I still have relatively good hearing.
I'm pretty impressed! Now to take it upstairs and try it as a preamp to my Aleph 30.
With electronics I tend to point the finger in the mirror as the root of all problems, so I was sure I fumbled something, but took a step back and decided to eliminate things 1 by 1.
Shorted input, and I had to flip the switch a couple times to make sure it was on! Ok, that's good! Tried my lab headphones (cheap akg ear buds) directly into my phone (Samsung Galaxy S9+) and would you guess what I heard? Yep, right channel at half volume, lol!
I grab my Salnote Zero iem (32ohm) and plug those into my phone, equal volume and expected sound quality. Ok, phone isn't shot. Plug into Noir, BOOM both channels at equal volume! Yes! Problem #1 "fixed" by replacing faulty test equipment.
Now for the hum. I disconnect the 3.5-RCA splitter from my phone and the hum is still there and acting like RF interference, as I move it around I can hear it changing. Wiggle the super extra long fly wires and yep, it changes too. Not much, but you can hear it.
I grab my Kindle Fire 7 to try a different source and instantly when I plug the splitter cord in it goes dead silent!
WooHoo! And DAMN this thing sounds good! Boy, what a relief it is to know I actually got it right the first time and just had faulty test equipment! Quiet, is an understatement! This thing is black. Like no moon, underground in a cave. Can't hear a thing and I still have relatively good hearing.
I'm pretty impressed! Now to take it upstairs and try it as a preamp to my Aleph 30.
Remind yourself: there are four transistors inside the box. Two in the left channel and two more in the right.
Slightly related, I've also fixed the hum issue on my phone, I guess its been a while since I've cleaned the jack and it was full of fuzz and lint, enough to not allow it to make contact at the tip. Lesson learned!
My Noir is working and sounds excellent using my old Sennheiser 595 headphones and also with Sony WH-1000XM5 (16r impedance).
I haven't fitted a regulator for the remote vol pot as yet.
I decided to make some measurements with REW and my Behringer UAC222 audio interface.
The results are impeccable and the Noir also makes a fine preamplfier - just needs more inputs and a selector (I plan on fitting a second set of input RCAs). Measured at 500 and 50mv in. Output to the 27k input impedance of the UAC222.
I am staggered at what can be achieved with only 2* active devices. It makes a mockery of all of the 'state of the art' opamps.
* okay, one is a darlington transistor.
I am using a 24v Chinese linear PSU. https://www.ebay.co.uk/itm/125867248299
What we need is a more compact version for preamp use only (hint) and with onboard 24v regulator. (eg LT 1965


)

I haven't fitted a regulator for the remote vol pot as yet.
I decided to make some measurements with REW and my Behringer UAC222 audio interface.
The results are impeccable and the Noir also makes a fine preamplfier - just needs more inputs and a selector (I plan on fitting a second set of input RCAs). Measured at 500 and 50mv in. Output to the 27k input impedance of the UAC222.
I am staggered at what can be achieved with only 2* active devices. It makes a mockery of all of the 'state of the art' opamps.
* okay, one is a darlington transistor.
I am using a 24v Chinese linear PSU. https://www.ebay.co.uk/itm/125867248299
What we need is a more compact version for preamp use only (hint) and with onboard 24v regulator. (eg LT 1965





@Mark Johnson
How about a preamp only pcb with 4 onboard relay switched inputs, 12v regulated supply for remote volume pot. (mine is working and does not introduce noise when moving and is a good upgade for those with limited mobilty.)?
Pcb could be smaller as the bias can be a good bit lower as it would not need to drive into less than about 1k.
How about a preamp only pcb with 4 onboard relay switched inputs, 12v regulated supply for remote volume pot. (mine is working and does not introduce noise when moving and is a good upgade for those with limited mobilty.)?
Pcb could be smaller as the bias can be a good bit lower as it would not need to drive into less than about 1k.
Noir's schematic is public domain; nobody owns it and nobody can prevent you from re-implementing it in other form-factors. At least two members have uploaded photos to this thread, showing Noir PCBs they created themselves. It's not a gigantic task to lay out your own board and send its Gerbers to a fab; then you can get exactly the board dimensions (X by Y) and aspect ratio you need, to fit into a specific chassis of your choosing. You can also add whichever bells and whistles (features) you desire. Perhaps a relay based stepped attenuator with 63 precisely matched volume settings? Perhaps an AmyAlice supply filter* or two? Whatever your heart desires. Design it, lay it out, send it off to fab (tutorial here), and have fun building it.
(*) also public domain, also found here on the diyA forums
(*) also public domain, also found here on the diyA forums
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