The RC ground breaker from signal ground to the chassis is for ground loop noise reduction. The voltage across the resistor is in the millivolt range. The capacitor in parallel is for RF rejection. I don't know what you mean by "survive to blow the fuse". Will "what" survive to blow the fuse? The chassis is at earth ground. You can leave the filter out if you wish and connect the signal ground directly to the chassis.
Just in the event you don't get a shock in a not properly failure proof designed system, yes, life will continue. In such a way
I am not saying this grounding scheme is not safe, just that I am too curious some times
I mean that if it is possible to DON'T put the resistor and just put the capacitor for RF filtering
You can't leave the resistor out just like that - your signal ground would be ill-defined. You would have to replace it by a piece of wire (the cap would be useless then) to ensure that ground reference for your audio path is defined.
From a safety point of view this is quite irrelevant. Important is the safe and sound connection of the earth wire of the 3-wire power cord to the chassis.
Any failure causing a meaningful charge/voltage on the chassis will blow the fuse - and that's what you want.
In practical terms, signal ground and safety ground are on almost the same potential. The resistor lifts signal ground a few mV above earth ground level helping to break ground loops (as scitizen17 stated earlier).
Cheers,
Martin
Why would I NEED to reference PS ground to Protective earth? My audio signals can be referenced to power supply ground and completely isolated from protective earth, and will sound good. Even using an input audio transformer, it will provide galvanic ground isolation, so the amp will be totally floating.
Sooooooo..... if there's no real need to tie PE (Protective Earth) and PS-GND (Ground side of PSU capacitors) regarding audio performance, then the need should came from safety issues.
Pardon me if I get boring with this matter
I would recommend reading that article, is the solution I've always implemented and I am going that route with this amp too. Don't really like the idea of NOT providing a direct path for current from the 0 volts rail to Protective Earth.
Earthing (Grounding) Your Hi-Fi - Tricks and Techniques
Earthing (Grounding) Your Hi-Fi - Tricks and Techniques
If that's the solution you've always used, why all the questions? No one here ever suggested to NOT provide a direct path for current from the 0 volts rail to Protective Earth.
The grounding scheme for the kit has always included a direct current path from circuit ground to chassis ground.
I can't agree with that, there's no direct path, there is a 10 ohm resistor.
i wrote a long and very well detailed reply to this but your bulletin board software kicked me off and now its lost to the ages, oh well screw it.
One of the main reasons for me buying his master kit was that I like his style of using PIO caps in the power supply, I remember back when I used to frequent diyaudio.com in 2003-2006 I wanted nothing but the very reliable amplifier that I could build, PIO catered to that, and I wanted a KT amp too!!
So this kit has been 9 years in the waiting.
I've been listening to chicago blues while it rains outside and thought about this reply while reading your comment.
In summary of what i was going to say is that people are modders nowdays, not designers, people dont want to build a tube amp from the ground up any more, the reason why they buy those cheap rubbish amps from china isnt because they think its the best its because they want to believe that its the best and not get disappointed when it arrives and it works, even if there are electrical flames shooting out the top of it they will still think that its operating perfectly.
Thats how far they are willing to go to believe the myths and hype that people tell them.
The reason why they are considering buying a cheap chinese amp in the first place is because they are looking for a replacement of their nasty sounding amp or device that is giving them a headache, thats what spurs them into looking into higher fidelity products.
If microsoft can get away with selling something like windows 8 with this method then we are in for some serious trouble in future.
and if people like that company which sold a product to get rid of the metro interface and put the start menu back on the screen can make money then the future is still bright.
I think that with the whole ease of modding a computer (or car) its become too easy for people to get the best, thanks to rap culture nowdays the best is simply whatever has diamonds and gold on it or has an extremely high price and brag value.
We even have american gangs over here in australia, and they are who dictate our young ones belief system and purchasing descisions. simply because its "cool". I dont have anything against cool stuff but I did grow out of it and stop letting other people dictate what I wanted, but these days you see even 40 year old people catering to this style of society and trying to be "badass".
People are consumers nowdays, not thinkers, they hit that purchase button after 3 or 5 minutes of reading about or looking at an amplifier. and because the photos are all photoshopped they believe the lies.
I dont believe this is the case on diyaudio or any of their sellers, but when you go outside of these borders you see all kinds of trickery going on, tho you do have good products too but you need to know where to go and thats a long process.
suffice to say that I'm going to be putting a solid aluminium etched US flag on the front of my amp, so I know exactly where it came from and when it came from and who made it.
I wish everyone in the US the best of luck and hope the future is just as bright as the last few hundred years for them and for us all.
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I've decided to not go with a black coat at all, but instead with a highly polished aluminium finish, I've got a dremel and a power drill, all I need is the polish wheels/sand discs and some time at it
I want to see my tubes in the reflection off the top.
I've also got a couple of goldy coloured (really yellow) 10mm LED's which I might put in underneath the KT88's to illuminate them (the leds are very dim so its ok!) (might have to remove a section of the tube base to let them shine through but thats ok)
The side panels should be as dark walnut as I can get, I'll probably have to re-stain them.
I've also decided upon the colour of the bellhousings:
Thinking about a highly polished gold coat.
I want to see my tubes in the reflection off the top.
I've also got a couple of goldy coloured (really yellow) 10mm LED's which I might put in underneath the KT88's to illuminate them (the leds are very dim so its ok!) (might have to remove a section of the tube base to let them shine through but thats ok)
The side panels should be as dark walnut as I can get, I'll probably have to re-stain them.
I've also decided upon the colour of the bellhousings:
Thinking about a highly polished gold coat.
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It's not easy albeit possible to polish aluminium to an extend that it looks almost like chrome-plated. But as I said, it's very laborious due to the softness of the metal (been there, done that).
Copper for example is much easier to polish to a mirror-like surface. Chrome-plating that might be the easier choice.
YMMV
Best,
Martin
Copper for example is much easier to polish to a mirror-like surface. Chrome-plating that might be the easier choice.
YMMV
Best,
Martin
better hope thare are no scratches when you start the 'grinding'
and also be exstremely careful not to make one while working on it
btw, I think what you see of this type of work will mostly be chromed metal
but stainless steel will most likely be polished
when polishing alu I use finest wetsanding paper, but sainding dry
then it shines
but clean it carefully constantly with water
and flush the sanding paper all the time
just one little small sandcorn, and its all wasted
but whatever, its DIY, who says it should be perfect
and also be exstremely careful not to make one while working on it
btw, I think what you see of this type of work will mostly be chromed metal
but stainless steel will most likely be polished
when polishing alu I use finest wetsanding paper, but sainding dry
then it shines
but clean it carefully constantly with water
and flush the sanding paper all the time
just one little small sandcorn, and its all wasted
but whatever, its DIY, who says it should be perfect
no no, not chrome, mirror finish, on everything.
I was thinking of some 320 grit wet and dry to even out any cuts/scrapes/edges and to flatten the chassis off by hand so I know exactly how I'm going and don't screw it up and scratch it badly.
Thats if its pretty bad already.
Then move onto 1000 grit W&D to give it an even softer surface to work on and polish.
Then hitting it with a large mop wheel on a 650 watt Makita power drill and some brown cutting compound.
Then using some blue cutting compound to bring it to a mirror finish on a 2nd mop.
I was thinking of some 320 grit wet and dry to even out any cuts/scrapes/edges and to flatten the chassis off by hand so I know exactly how I'm going and don't screw it up and scratch it badly.
Thats if its pretty bad already.
Then move onto 1000 grit W&D to give it an even softer surface to work on and polish.
Then hitting it with a large mop wheel on a 650 watt Makita power drill and some brown cutting compound.
Then using some blue cutting compound to bring it to a mirror finish on a 2nd mop.
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Gloves + Full face respirator from S.E.A with a pre-filter, you don't want to breathe in metallic airborne dust!
OR get it in your eyes.
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Ah.
I'll be needing to give it a thin clear coat paint job afterwoods then inorder to seal it up and keep the mirror finish.
Correct?
Either that or electroplating it, or using a chemical reaction.
http://en.wikipedia.org/wiki/Chromate_conversion_coating#Aluminum
Nah that requires a huge amount of money
Clear coat it is, apparently.
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