"Dual mono" and True Dual Mono

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Spannko
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Re: "Dual mono" and True Dual Mono

Post by Spannko »

ThomasOK wrote: 2019-09-17 22:39

So I'm not sure how you would take the connection closer to mother earth.

I suppose one possible extension of the separate left and right grounds would be to have another circuit breaker and AC wall outlet so that you could have one channel on one circuit and one channel on the other, keeping the grounds separate back to the panel. A lot of work but it might be interesting.
Yes, this is the sort of thing I had in mind, although I’d recommend trying two power cables into the one breaker as well, to see which works best in your system. I’ve tried it on my system, and two breakers sounded worse, musically and sound wise.
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Re: "Dual mono" and True Dual Mono

Post by Spannko »

lejonklou wrote: 2019-09-18 09:08
ThomasOK wrote: 2019-09-13 17:44 Completely separate grounds for the left and right channel means that the only place the grounds of the two channels come together is at the AC power strip or the wall.

Even equipment that is dual mono in construction normally has the left and right signal grounds connected together. This is easily tested by checking for continuity between the two grounds with a VOM. With my current system you have separate left and right grounds in the cartridge, phono stages, preamps, power amps and speakers. So the grounds only come together at the power strip.
Sorry, I haven't paid proper attention to this discussion. Perhaps because it was buried in a 78 page long playground thread instead of having its own - which it deserves and therefore I made one.

With most HiFi units, even when they are said to be built as dual mono, the signal grounds are not separated but join one another, either on the circuit board or by going into the same chassis ground. This causes a ground loop, sometimes multiple ones, when the unit is connected to the next unit, as the RCA interconnects carry two grounds - left and right - which once again meet in the next unit. And if the signal ground is connected to the chassis ground, there are additional loops created by the grounds in the power cords, which meet in the power strip.

Ground loops are bad for the music. Sometimes a loop picks up hum or other noise, but even when it doesn't, it "muddies the water" of the reproduction. It's usually not until you remove it that you notice its degradational effects.

With my true Mono units - SINGularity, Sagatun Mono and Tundra Mono - where each channel is housed in its own case and with the floating signal ground layout that I use, left and right signal grounds never meet. They run completely separated all the way from each coil in the cartridge to the coils in each speaker. They don't meet in the power strip.

The chassis grounds are arranged as a star and meet only in the power strip. Interestingly it still matters in which order the power cords are plugged into the power strip, and I have yet to hear a star grounded strip sounding better than the best regular strips.

Left signal and left signal ground run as an isolated chain from cartridge to speaker. Right signal and right signal ground run as an isolated chain from cartridge to speaker. The two don't meet each other and they are shielded on their journey by the chassis grounds.
I know very little about electronic circuit design but I’m wondering if the “protective earth” causes more problems than it solves?

To help you understand my thinking, here are a few thoughts bouncing around my head:

1. Take a simple circuit - battery +’ve > wire > bulb > wire > battery -‘ve This doesn’t need a ground to work.

2. Domestic power supply - Live > cable > bulb > cable > Neutral This also doesn’t need a ground to work.

3. International Space Station - good luck getting a good ground up there!

My guess is that the Singularity/Sagatun/Tundra work on the same principle.

My understanding is that the green/yellow cable is not an earth wire. It’s a Circuit Protective Conductor (CPC) intended to provide a safer route for the current to return back to its source should the enclosure become live in the event of a fault (rather than through you or I!)

So, would it be better to dispense with the CPC altogether by using a double insulated design inside a Faraday cage type enclosure which is enclosed in a non-conductive material?
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Re: NOT FUNNY

Post by Defender »

Ron The Mon wrote: 2019-09-18 21:54
Defender wrote: 2019-09-18 21:03 ...search: audiophile club athens,...

in the video you see how to do it - this guy knows it (its really funny) ;)
I watched your linked video and it saddens me.

What I wrote above is not funny or a joke. It is based on science and current U.S. electrical code. If you wish to mock me and call me a fraud, send Fredrik a Private Message and have me banned from here.

I take hi-fi reproduction very seriously. I may sometimes kid here but nothing I have written should be considered a joke.

Ron the Mon
Hi Ron,
I have difficulty to say sorry for something which was absolutely not my intention but will do so: sorry for that this message came at the wrong place and actually made you feel that.
It has nothing to do with what you wrote which is all correct to my opinion it was not questioning anything you wrote at all.
Our electrical system is different from yours and I absolutely agree with your approach - you can actually measure your earth loop resistance.
We have L1 N and PE. L1 is live N is null or natural and PE is the Earth.
Earth is connected to N in the circuit breaker - and is going with a short and thick copper wire to a pole in the ground either outside house or even inside the house (to keep distances short).

Why did I mentioned the video: because there are people who take their hobby serious as we do with sometimes different approaches.

Sorry again if it made you feel offended which was not my intention at all.
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Re: "Dual mono" and True Dual Mono

Post by lejonklou »

Spannko wrote: 2019-09-18 23:56I know very little about electronic circuit design but I’m wondering if the “protective earth” causes more problems than it solves?

To help you understand my thinking, here are a few thoughts bouncing around my head:

1. Take a simple circuit - battery +’ve > wire > bulb > wire > battery -‘ve This doesn’t need a ground to work.

2. Domestic power supply - Live > cable > bulb > cable > Neutral This also doesn’t need a ground to work.

3. International Space Station - good luck getting a good ground up there!

My guess is that the Singularity/Sagatun/Tundra work on the same principle.

My understanding is that the green/yellow cable is not an earth wire. It’s a Circuit Protective Conductor (CPC) intended to provide a safer route for the current to return back to its source should the enclosure become live in the event of a fault (rather than through you or I!)

So, would it be better to dispense with the CPC altogether by using a double insulated design inside a Faraday cage type enclosure which is enclosed in a non-conductive material?
You're right that the reason we have mains earth is safety. And that's a good thing! But it can also be used as a sink for high frequency noise. And as such it's quite beneficial for sound quality. You can tie signal ground to it or not, both approaches work but I have had the best results when I don't.

You can use a reinforced insulation around the electronics instead of a protective earth, that's called a class II power supply. They're very common, as a lot of units don't have a power cord with an earth conductor. You can use class II on every part of the system, that works. But then if you put every unit in a metal box, connect a wire to each metal box and bring all those wires together in one point, it usually sounds a little better. And if you connect that point to the ground, it usually sounds a little better still.

I'm very pleased with the mains ground and don't want to get rid of it.

And by the way, you wrote:
My guess is that the Singularity/Sagatun/Tundra work on the same principle.
Yes, and so does every other piece of equipment. The protective ground is not required for your system to work. You can connect all your power cords to a power strip without grounded outlets and it will still work. But I suggest you don't, because the mains ground makes it safer and also improves sound quality.
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Re: "Dual mono" and True Dual Mono

Post by Spannko »

lejonklou wrote: 2019-09-19 09:48
Spannko wrote: 2019-09-18 23:56I know very little about electronic circuit design but I’m wondering if the “protective earth” causes more problems than it solves?

To help you understand my thinking, here are a few thoughts bouncing around my head:

1. Take a simple circuit - battery +’ve > wire > bulb > wire > battery -‘ve This doesn’t need a ground to work.

2. Domestic power supply - Live > cable > bulb > cable > Neutral This also doesn’t need a ground to work.

3. International Space Station - good luck getting a good ground up there!

My guess is that the Singularity/Sagatun/Tundra work on the same principle.

My understanding is that the green/yellow cable is not an earth wire. It’s a Circuit Protective Conductor (CPC) intended to provide a safer route for the current to return back to its source should the enclosure become live in the event of a fault (rather than through you or I!)

So, would it be better to dispense with the CPC altogether by using a double insulated design inside a Faraday cage type enclosure which is enclosed in a non-conductive material?
You're right that the reason we have mains earth is safety. And that's a good thing! But it can also be used as a sink for high frequency noise. And as such it's quite beneficial for sound quality. You can tie signal ground to it or not, both approaches work but I have had the best results when I don't.

You can use a reinforced insulation around the electronics instead of a protective earth, that's called a class II power supply. They're very common, as a lot of units don't have a power cord with an earth conductor. You can use class II on every part of the system, that works. But then if you put every unit in a metal box, connect a wire to each metal box and bring all those wires together in one point, it usually sounds a little better. And if you connect that point to the ground, it usually sounds a little better still.

I'm very pleased with the mains ground and don't want to get rid of it.

And by the way, you wrote:
My guess is that the Singularity/Sagatun/Tundra work on the same principle.
Yes, and so does every other piece of equipment. The protective ground is not required for your system to work. You can connect all your power cords to a power strip without grounded outlets and it will still work. But I suggest you don't, because the mains ground makes it safer and also improves sound quality.
Very interesting. Thank you.
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