Nuuk said:
Yes, uncle Nick. (c) Pedja.😎
In your arrangement you could have signal star ground?
The little board on the right could be removed and the resistors also connect at the one in the middle.
From that little board on the middle (signal star ground), take a small resistor (1 to 2.7 ohms) to the power star ground.
The chips could be even closer this way, more silent amp.
Or you have everything independent (including PSU) or the ground should be only one.
I miss DIN plugs...🙄
😀
Note: the right input caps would have to be side by side with the left ones.
And Nick, you use very thin PSU wires...
Use at least 1.5mm (I use multi-strand), and for ground, 2.5mm.
Thanks for your comments Carlos. 🙂
To clarify, are you saying that there is no need for a signal ground star for each channel?
Does that apply in the case of using a single signal ground star or where you have one per channel as well?
This amp is silent
There is just no noise at all even with my ear touching the speaker. No switch on thump or noise when the amp is powered down. I believe a slightly larger gap like I have in this case helps cooling too!
Could you explain? They are still widely avaialble (at least here in the UK) 😕
Point taken Carlos. I prefer solid core wires to stranded and larger diameter solid core wires are quite stiff and difficult to work with. I keep meaning to get some 0.8mm solid core that would be an improvement on the 0.6mm. Is this a safety issue or a performance issue?
PS And thanks to Uncle Pedja for the connecting wire tip! 🙂
To clarify, are you saying that there is no need for a signal ground star for each channel?
Does that apply in the case of using a single signal ground star or where you have one per channel as well?
This amp is silent
There is just no noise at all even with my ear touching the speaker. No switch on thump or noise when the amp is powered down. I believe a slightly larger gap like I have in this case helps cooling too! Could you explain? They are still widely avaialble (at least here in the UK) 😕
Point taken Carlos. I prefer solid core wires to stranded and larger diameter solid core wires are quite stiff and difficult to work with. I keep meaning to get some 0.8mm solid core that would be an improvement on the 0.6mm. Is this a safety issue or a performance issue?
PS And thanks to Uncle Pedja for the connecting wire tip! 🙂
Nuuk said:
Yes.
Nuuk said:
Both.
Nuuk said:This amp is silent
Yes, your arrangement is good, I believe in you.
Nuuk said:
That is true, but a thick heatsink would help.
Better to have a thick heatsink to avoid "hot-spots" than a thin and large one.
Nuuk said:
I know they are, and some are really good, like those locking type plugs that Naim uses.
The problem is that this is not a standard anymore, so RCA to DIN adapters would be needed.
Naim is including RCA inputs on their gear too, market dictates it.
DIN plugs make the grounding arrangements much tighter and better. Single ground.
Nuuk said:
Performance.
Large currents travel through them.
And the ground is common, it should be the thicker wires (as you have).
Safety is not an issue here, I don't think those thin wires will put your amp on fire anyway.
If you like solid core, why not 1.5mm?
Everything made with solid core wire, well arranged and braced can be very good looking.😎
And it still has some flexibility.😉
Yes, I guess so. I am just a little worried about connecting such stout wires to those very fragile chip pins in the case of P2P construction!
I may try 1.0mm next time though. That is the size of wires used for household lighting circuits in the UK (and I suspect Europe too).
I had no trouble connecting large wires to the pins, but the pins have been reinforced with the capacitor leads, so they form a reasonably solid connection point. The wires are also cut to the right length and cable-tied to support each other.
The wire is fairly thick probably about 2.5mm. I buy 5 core flex and strip the cores out, so I get indentical wire with 5 different colour insulation.
BTW: I hope there is an attachment attached. 😱
Attachments
Nuuk said:
😱
1mm in the UK?
We use 1.5mm for lighting around here.
And plugs on the wall usually have 2.5mm, some good installations even have 4mm.
Yes, you can buy these solid core wires cheap, they are used for electrical installations.
A suggestion on wire colors inside the amp:
Blue: V+
Black: Ground
Brown: V-
Green/Yellow: Earth
Standard colours inside machine are : L - brown or black, N - blue, PE - green / yelow. Plus - red, minus - dark blue, ground - green.
Upupa Epops said:
Yes, but these colours are not easily available in this type of wire.
That's why I suggested those colours.
EDIT: talking about standard colours and layout, in RCA plugs the red is the right channel, this is universal.
A standard too is the layout, the disposition of the plugs on the back pannel.
Normally, with a vertical layout, left channel RCA female is the top one, the right channel (red) is the bottom one.
You can connect the wires without looking.
But there are exceptions.
With an horizontal layout, looking at the front pannel, on the back the right channel is the right plug.
Again, you can connect the wires without looking.
But there are exceptions.
Like my AA dac.
I always make things standard, I give very importance to these things, I like to be able to plug and unplug cables without having to look at the back.
It's a shame that there are exceptions on commercial products.
and most importantly Greg - you have securely fixed those caps in place. If the caps wires can move, you will most likely break a pin. 😉
Very neat work by the way!
I was just testing to see if you paying attention Carlos. 😀
Yes, it is 1.5mm in the UK too. The 1.00mm wires that I was thinking of come out of the stranded cable used for making the ground connections in the mains supply (bonding water pipes etc). They can be used if they are 'unstranded' and insulated.
I will stick to
Red: +V
Black: -V
Blue: Ground
Green/Yellow: Earth
but I guess for DIY, it is really down to what each of us has got used to! 😉
Thanks, but a little too tight. I can't fit a T-network without a complete rebuild. I just happen to have a full picture. 😀
I got close. Except for minus - dark blue (white) and ground - green (green/yellow)
Thanks. Everything ties together quite rigidly so I don't think a pin will break. 😉
Attachments
carlosfm said:
Morphine
What a CD, Carlos, The recording is just one of the best, It's not really my cup of thee, but it's really good, sound wise.
I bought the CD with the title GOOD! WOW!
Thanks for the tip🙂 🙂
Audiofanatic 😉
Good enough for Uncle P - good enough for me! 😉
I just ordered Movimento and Antologia from the library. 🙂
Audiofanatic said:Morphine
What a CD, Carlos, The recording is just one of the best, It's not really my cup of thee, but it's really good, sound wise.
I bought the CD with the title GOOD! WOW!
It's not the music you like at first listening, you will learn to like it, give it some more listens, you will be addicted.
You won't go wrong with any Morphine album.
Get'em all if you can, if you get to love'em.
Unique (different, original) bass playing, unique sax.
Good songs, good lyrics, good music.😎
Nuuk said:
I really have a vice for good music, since I was a kid.
The vice is spreading, that's very good.
Another pearl, shiny new, just released, just bought:
Ben Harper and the blind boys of Alabama - "There will be a light".
Excellent music, and, what's more, an excellent test for any system.
Very good recording, and the bass is outrageous, incredible.
Your speakers will jump out of the supports to the floor.
Let's see who has serious amps, bass has to be tight, you have to be punched in the chest, the house must not vibrate.😀
Buy it!
It's addictive.
PS: I have all of the Ben Harper albums (as well as Morphine😉 ), they are all excellent.
Oh, Ben doesn't pay me anything.😀
Re: Re: Re: Re: Re: Re: Another T
I've done pretty much that, and the noise is now a little over 1ma AC. Plenty good enough for practical purposes, as the hum is completely inaudible at less than any actual listening distance. I would guess that totally quiet would require different boards or point to point wiring.
The output is very much the same as on my NI amp built with the same boards. One thing is different, however, and that is that the inverted amp has much more noise with nothing connected to the inputs. The NI amp is completely indifferent regarding the input jacks (shorted, connected, open). I haven't thought this one through yet, but seems to make sense regarding the different ground paths for the feedback loop. Do I surmise correctly here?
Sheldon
carlosfm said:
I've done pretty much that, and the noise is now a little over 1ma AC. Plenty good enough for practical purposes, as the hum is completely inaudible at less than any actual listening distance. I would guess that totally quiet would require different boards or point to point wiring.
The output is very much the same as on my NI amp built with the same boards. One thing is different, however, and that is that the inverted amp has much more noise with nothing connected to the inputs. The NI amp is completely indifferent regarding the input jacks (shorted, connected, open). I haven't thought this one through yet, but seems to make sense regarding the different ground paths for the feedback loop. Do I surmise correctly here?
Sheldon
Sheldon said:
No need for P2P.
Next time you will know better what you need to make a board for a completely silent amp.😉
Sheldon said:
Mmmm...
You use an input buffer, right?
So, the amp always sees a previous stage.
Do you have a resistor from input to ground? If you have an input buffer, put the resistor before it.
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