darTZeel NHB-108 Model 2 - The Best Stereo Amplifier In The World Just Got Way Better!

[all2ofme]

Did you go one XLR per channel, then? Would love to see a pic

Measured some screws on my 18NS power supply and got lower impedance on some of the screws next to the IEC, but if I remember correctly you (or perhaps someone else here) got the nod from darTZeel to use one of the ones along the PSU’s top panel. Which one specifically?

(Love love love my darTZeels. Just fantastic gear.)

 

[Porsche]

the best in the world, that's funny, there is NO best, I will keep my Burmester

 

[all2ofme]

I'm sure your Burmester is fantastic. Would love to hear one one day. It might even tie in nicely to a possible shared love of Porsches

(If the "best" you're referring to is the one in the thread title, I'll agree with you that hyperbole and absolutes aren't often helpful. But that thread title was also written five years ago. We've moved onto way nerdier things, like how to ground the thing ;-))

 

[Zeotrope]

Did you go one XLR per channel, then? Would love to see a pic

Measured some screws on my 18NS power supply and got lower impedance on some of the screws next to the IEC, but if I remember correctly you (or perhaps someone else here) got the nod from darTZeel to use one of the ones along the PSU’s top panel. Which one specifically?

(Love love love my darTZeels. Just fantastic gear.)

Check out post #58 in this thread
I measured ~0.1ohm resistance using this screw.

Probably better; but doubt it will make a difference, to use the circled screw pictured below instead, but note that it’s very short, so you will need a longer screw, and you’ll need to secure the nut from the inside while you tighten It. Note that it’s connected to the chassis/case, and I used the post you see to the left of the AC connector.

The reason why the ground makes a difference on the preamp is because the signal/chassis ground is still connected to the AC mains ground, even though it’s battery powered. This is must be why @Mike Lavigne noticed that the AC cord makes a difference on the 18NS. Note that you can set the ground lift to on, which may make this unnecessary; but I haven’t changed it (My ground jumper is “Connected” inside the preamp).

Will post a photo of the back of the amp shortly.

 

[all2ofme]

Ha ha, yes — I saw post #58, but I wasn’t 100% clear on which screw was shown. Too zoomed in

The internal pic you just posted circles the screw where I got the lowest measurement, which is encouraging. Whether or not the screw choice makes a difference here is another thing entirely, of course.

Very interesting re: Mike’s findings. Will be a pity if my mate who just bought a Model Two and 18NS needs one more nice power cable

 

[Zeotrope]

I used the screw on top of the case, in the upper left corner - you can see the screw post in the image above. It’s the closest top cover screw to the AC inlet.

 

[Zeotrope]

You can see the XLR Omega ground cables here.

 

[all2ofme]

Amazing. Thanks very much indeed. Will be interested to see how this pans out

 

[struts]

Check out post #58 in this thread
I measured ~0.1ohm resistance using this screw.

Probably better; but doubt it will make a difference, to use the circled screw pictured below instead, but note that it’s very short, so you will need a longer screw, and you’ll need to secure the nut from the inside while you tighten It. Note that it’s connected to the chassis/case, and I used the post you see to the left of the AC connector.

The reason why the ground makes a difference on the preamp is because the signal/chassis ground is still connected to the AC mains ground, even though it’s battery powered. This is must be why @Mike Lavigne noticed that the AC cord makes a difference on the 18NS. Note that you can set the ground lift to on, which may make this unnecessary; but I haven’t changed it (My ground jumper is “Connected” inside the preamp).

Will post a photo of the back of the amp shortly.

Hi Zeotrope, Just passin' through and reading this thread out of idle curiosity (hi Ben!) and saw your pictures of the ALTAIRA installed on your 18NS/108. Although I understand the cable shoes are attached to bolts that go into or through the chassis plates the cable shoe itself is not making galvanic contact with the case because of the anodising. Anodising is actually a very good insulator! Best practice is to Dremel away the anodising under the shoe for chassis earthing wires (my apologies if you have done this but it doesn't look like it). Of course that may influence your choice of which screw to use!

 

[Zeotrope]

Hi Zeotrope, Just passin' through and reading this thread out of idle curiosity (hi Ben!) and saw your pictures of the ALTAIRA installed on your 18NS/108. Although I understand the cable shoes are attached to bolts that go into or through the chassis plates the cable shoe itself is not making galvanic contact with the case because of the anodising. Anodising is actually a very good insulator! Best practice is to Dremel away the anodising under the shoe for chassis earthing wires (my apologies if you have done this but it doesn't look like it). Of course that may influence your choice of which screw to use!

Hi! Thanks for your message.
Actually, DarTZeel uses the 18NS power supply case as a ground point. You can see this in the interior photo of the PSU. So the case screw is perfectly fine. Again, resistance was measured to be < 0.1 ohm. Appreciate the comment though, never hurts to check!

 

[struts]

Sounds like it's all good. I was just going on what I could see in the photos which don't reveal what is going on under that screw head. Is it going into a tapped hole with good contact with bare metal all the way through or is it going through a drilled hole to a nut on the other (anodised) side? If the latter it could conceivably be making no galvanic contact, I guess you are saying it is the former. What is the resistance measurement you refer to? Between which points? Cable shoe and ???

 

[Zeotrope]

Sounds like it's all good. I was just going on what I could see in the photos which don't reveal what is going on under that screw head. Is it going into a tapped hole with good contact with bare metal all the way through or is it going through a drilled hole to a nut on the other (anodised) side? If the latter it could conceivably be making no galvanic contact, I guess you are saying it is the former. What is the resistance measurement you refer to? Between which points? Cable shoe and ???

Hi, I actually just measured resistance again, between A and B (i.e., the screws that are threaded into both points), and it’s 0.9 ohm.
Shunyata says resistance should be <1 ohm for a good ground connection, so I think it’s fine.
In my notes when I installed it I measured 0.1ohm between the actual AC ground plug receptacle and the screw post (maybe I made a mistake, but I doubt it .

 

[struts]

Hi, I actually just measured resistance again, between A and B (i.e., the screws that are threaded into both points), and it’s 0.9 ohm.
Shunyata says resistance should be <1 ohm for a good ground connection, so I think it’s fine.
In my notes when I installed it I measured 0.1ohm between the actual AC ground plug receptacle and the screw post (maybe I made a mistake, but I doubt it .

Well It definitely sounds like my concerns were unfounded although I still don't understand from looking at the photos how/where the galvanic contact is being made. All I can see is anodised surfaces! Anyway, thanks for answering, I was just curious.

 

[Zeotrope]

Well It definitely sounds like my concerns were unfounded although I still don't understand from looking at the photos how/where the galvanic contact is being made. All I can see is anodised surfaces! Anyway, thanks for answering, I was just curious.

I'm not 100% sure either, but the ohm meter doesn't lie! Thanks for your interest and curiosity, I appreciate it!

 

[struts]

I'm not 100% sure either, but the ohm meter doesn't lie!

I'm with you on that. I have learned to trust my Fluke more than my own eyes!

 

[Zeotrope]

I'm with you on that. I have learned to trust my Fluke more than my own eyes!

Fluke here is as well!
”It’s not a fluke if it’s a Fluke” ?!

 

[Zeotrope]

Has anyone heard a fairly loud ”pop” through the speakers when touching the front faceplate of the 18NS? I’m guessIng it was static electricity as it’s winter here and the air is drier (although my house is well humidified)… but still not sure why, since my Ground jumpers are set to “Connected”?

 

[Mike Lavigne]

Has anyone heard a fairly loud ”pop” through the speakers when touching the front faceplate of the 18NS? I’m guessIng it was static electricity as it’s winter here and the air is drier (although my house is well humidified)… but still not sure why, since my Ground jumpers are set to “Connected”?

all the time if i don't touch something to ground myself before i touch the 18NS. particularly in the wintertime with less humidity. at the coldest part of the winter i need to slide my hand onto the 18NS while it's still touching the rack.

i typically touch my wood rack or my wood top layer on my Herzan. something not metal. this varies based on shoes you are wearing and type of floor/carpet.

 

[Zeotrope]

all the time if i don't touch something to ground myself before i touch the 18NS. particularly in the wintertime with less humidity. at the coldest part of the winter i need to slide my hand onto the 18NS while it's still touching the rack.

i typically touch my wood rack or my wood top layer on my Herzan. something not metal. this varies based on shoes you are wearing and type of floor/carpet.

Thanks Mike! So you get that “pop” through the speakers as well. I don’t think anything was damaged.
Shouldn’t it drain through the AC ground (my ground jumpers are set to “Connected”), or not because the battery charger is disconnected completely while in operation? I’ll ask Herve.

Touching wood will drain it? What about just touching the volume dial?

 

[Mike Lavigne]

Thanks Mike! So you get that “pop” through the speakers as well. I don’t think anything was damaged.
Shouldn’t it drain through the AC ground (my ground jumpers are set to “Connected”), or not because the battery charger is disconnected completely while in operation? I’ll ask Herve.

Touching wood will drain it? What about just touching the volume dial?

touching something non conductive will drain the static charge from your body to a degree for a brief period of time.

which mostly works for me. these last few weeks with it under freezing and the air dry i've had to be more deliberate about it. most of the year the humidity is sufficient that a brief touch is enough. the 18NS is sensitive to these things considering it's battery power and minimalist circuits. but it's never been a big deal really.

another thing i do is to turn the 18NS on, let it go thru it's start-up, and put it in mute prior to turning on the amps. that's the best fool proof approach.