|
|
Post by Dr Bunsen Honeydew on Jul 10, 2014 9:26:23 GMT
|
|
|
|
Post by welder on Jul 10, 2014 9:44:33 GMT
|
|
|
|
Post by MartinT on Jul 10, 2014 9:53:35 GMT
The P10 has one, so don't worry. |
|
|
|
Post by Dr Bunsen Honeydew on Jul 10, 2014 10:04:24 GMT
It depends how they do it. Filter design is a black art and all of them increase source impedance, some less than others.
|
|
|
|
Post by pre65 on Jul 10, 2014 11:17:07 GMT
The DC blocker I built was very very similar to the Rod Elliot one, but I'm sworn to secrecy about the differences.  |
|
|
|
Post by MikeMusic on Jul 10, 2014 12:30:18 GMT
Yes I'd need a bit more encouragement than that to just buy it and cross fingers
Home made for £70-175 or allegedly £400 new
Might be easy to make for someone that knows what they are doing (not me)
|
|
|
|
Post by MikeMusic on Jul 10, 2014 12:33:17 GMT
Thanks (oh no not another box ...) |
|
|
|
Post by MikeMusic on Jul 10, 2014 12:33:59 GMT
The P10 has one, so don't worry. Top man McGowan ! Good news |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 11, 2014 8:37:06 GMT
Very rarely do I find myself in agreement with the Doc!
However I would suggest that including large voltage smoothing caps along with pair of 1000Vac full bridge rectifiers will have the desired results even with used in conjunction (IE before) a mains regenerated that has one incorporated.
Bryston have been building them into their amplifiers for many years now
|
|
|
|
Post by danielquinn on Jul 11, 2014 8:47:34 GMT
Very rarely do I find myself in agreement with the Doc! As a high end audio dealer , it would of course to analogous to turkeys voting for xmas . 
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Jul 11, 2014 16:03:23 GMT
As a high end audio dealer , it would of course to analogous to turkeys voting for xmas .
Hello Daniel Could you decipher you post for me as that would help at lot! |
|
|
|
Post by gazjam on Jul 11, 2014 22:05:11 GMT
In my own Balanced mains setup at home I used a 2KVA transformer. Safety was inportant and RCBO's were fitted. Build thread here: tinyurl.com/Hardwired-balanced-mainsMajor improvement in my system, basically noise floor down, music up. Not tried a regen unit, but others have tried on combination with a BPS and said they work well together, not mutually exclusive which is exactly as the Doc says. |
|
|
|
Post by Dr Bunsen Honeydew on Jul 11, 2014 22:43:07 GMT
There is nothing unsafe about them. Just about every transistor class B or AB amp uses a split rail transformer as step down, do you have to use a RCB in every amp, of course not.
|
|
|
|
Post by onepoint5 on Jul 12, 2014 1:10:51 GMT
In my own Balanced mains setup at home I used a 2KVA transformer. Safety was inportant and RCBO's were fitted. Build thread here: tinyurl.com/Hardwired-balanced-mainsMajor improvement in my system, basically noise floor down, music up. Not tried a regen unit, but others have tried on combination with a BPS and said they work well together, not mutually exclusive like the Doc says. I have a balanced transformer and can cheerfully report the same influences, lower noise floor, far more open, you just hear the music, and less crud. Everything is plugged in, mac mini, DAC, amps the lot. Should have invested in one years ago. To experiment, a Monster Power conditioner upstream was evaluated mainly for protection system rather than for noise filtering. It didn't work, left the sound thin in comparison, couldn't stand it. For now the best results are an isolation transformer (x 2 the kVA of the balanced transformer) upstream. The principle reason is to smooth out the current lumps on the primary of the balanced transformer, creates less acoustic noise from the balanced transformer. Still looking for an under/overvoltage solution, just may go with a protection relay, current wise, everything is under control. Yes, RCBO on the output of the balanced transformer, easy to implement, and very important. As for regenerators.....noisy things, electrically, to maintain the same waveform with non linear loads (and a transformer with rectifier is definitely a non linear load), the regenerator has to be oversized by 1.6x. The distortion figures for regenrators vary from 3% (linear loads) to higher. The distortion from supply at home is 2% from the street, so are you gaining anything? If the voltage in the street is lower or higher than what your equipment can withstand, then it's on to the supply company to get their act together. Equipment tolerance is there for the device to function with a wide voltage variation, in the case of amps, can be -20% to +10%. Having a tightly regulated AC supply is not a requirement unless your turntable runs a synchronous motor, then again the turntable would have its own PSU for the motor anyway. If you own and are happy with a regenerator, go for it, very glad for you. For those that don't, there are alternatives and they work extremely effectively. |
|
|
|
Post by pinkie on Jul 12, 2014 9:01:59 GMT
There is nothing unsafe about them. Just about every transistor class B or AB amp uses a split rail transformer as step down, do you have to use a RCB in every amp, of course not. I don't understand. Are you saying that RCB's are unnecessary and do not provide protection from electric shock in mains electrical systems? The output from an isolating transformer is potentially full mains - 230v PD and at least 10 amps. It will be connected by a mains lead to a device. If I connect my amp to the wall socket and the dog chews through the lead while I am out of the house, the RCB will protect the dog. What protects the dog if it chews the lead on the output of a mains transformer? Surely there are 3000va there potentially? The RCB's in the house will be of no benefit since they are isolated from the dog-killing supply by a transformer. The output from a power amplifier is to the speakers via speaker cable and is usually about 100VA or so - not 3000va. I would have thought RCB's on the output of a device supplying mains voltage and current were a good idea |
|
|
|
Post by Dr Bunsen Honeydew on Jul 12, 2014 9:10:06 GMT
You are talking nonsense. Do you realise what has to fail in order for that to happen. You have a RCB in your house, you don't need another one. The very very worst that can happen is one leg of the balanced line i.e. 120v (considered relatively non lethal) will be available and if any significant current is drawn it will still trip the house RCB. It is like putting a plaster on top of a plaster. You really should stick to accountancy.
|
|
|
|
Post by pinkie on Jul 12, 2014 10:05:05 GMT
You are talking nonsense. Do you realise what has to fail in order for that to happen. You have a RCB in your house, you don't need another one. The very very worst that can happen is one leg of the balanced line i.e. 120v (considered relatively non lethal) will be available and if any significant current is drawn it will still trip the house RCB. It is like putting a plaster on top of a plaster. You really should stick to accountancy. Please don't keep telling me I'm talking nonsense. I prefaced my question by saying I didn't understand. Why can't you just answer a question civilly. My understanding, from the qualified electrician I have just consulted, is that the RCB is tripped by a differential between the live and neutral feeds on the primary circuit, and that they would not be affected by an event on the other side of the transformer. A circuit breaker (fuse) on the supply side of the transformer might be tripped by an excessive load (fault condition) on the output side of the transformer, but the reaction times are nowhere near as fast, and the sensitivity much less than with RCB's. That's why we have RCB's to protect us and don't just rely on circuit breakers (fuses) The potential difference between 2 of the wires in the lead my dog chewed is 240v due to the phase difference. Even at 120v - the issue of whether it is lethal or not depends on the current drawn. Are you teasing me? Are you telling me that all mains voltage in the USA or Japan is non-lethal, unprotected, and you can cheerfully stick your fingers in it? I do stick to accountancy. I ask advice of qualified engineers when considering doing anything with electricity. The highly qualified engineer I discussed this with gave me helpful explanations of why some mains treatment might benefit the sound produced by some audio equipment, and so I am now interested to learn more. But I am concerned that anything I try is safe for me and my family. |
|
|
|
Post by gazjam on Jul 12, 2014 10:11:38 GMT
Great post. In my own Balanced mains setup at home I used a 2KVA transformer. Safety was inportant and RCBO's were fitted. Build thread here: tinyurl.com/Hardwired-balanced-mainsMajor improvement in my system, basically noise floor down, music up. Not tried a regen unit, but others have tried on combination with a BPS and said they work well together, not mutually exclusive like the Doc says. I have a balanced transformer and can cheerfully report the same influences, lower noise floor, far more open, you just hear the music, and less crud. Everything is plugged in, mac mini, DAC, amps the lot. Should have invested in one years ago. To experiment, a Monster Power conditioner upstream was evaluated mainly for protection system rather than for noise filtering. It didn't work, left the sound thin in comparison, couldn't stand it. For now the best results are an isolation transformer (x 2 the kVA of the balanced transformer) upstream. The principle reason is to smooth out the current lumps on the primary of the balanced transformer, creates less acoustic noise from the balanced transformer. Still looking for an under/overvoltage solution, just may go with a protection relay, current wise, everything is under control. Yes, RCBO on the output of the balanced transformer, easy to implement, and very important. As for regenerators.....noisy things, electrically, to maintain the same waveform with non linear loads (and a transformer with rectifier is definitely a non linear load), the regenerator has to be oversized by 1.6x. The distortion figures for regenrators vary from 3% (linear loads) to higher. The distortion from supply at home is 2% from the street, so are you gaining anything? If the voltage in the street is lower or higher than what your equipment can withstand, then it's on to the supply company to get their act together. Equipment tolerance is there for the device to function with a wide voltage variation, in the case of amps, can be -20% to +10%. Having a tightly regulated AC supply is not a requirement unless your turntable runs a synchronous motor, then again the turntable would have its own PSU for the motor anyway. If you own and are happy with a regenerator, go for it, very glad for you. For those that don't, there are alternatives and they work extremely effectively. |
|
|
|
Post by gazjam on Jul 12, 2014 10:20:00 GMT
My £0.02 worth, having installed a BPS in my home. Having additional safety protection may indeed impact on ultimate sound quality, but for me having it there means I don't have to worry about "What if" scenarios that however unlikely, are statistically possible to happen. Having that worry would affect my enjoyment of the music and that alone made it worth it to me personally. I remember me and the Doc had a good (friendly  ) chat about it over on Hifi Subjectivist and I took his points on board, he DOES know what hes talking about. However as always there's different ways to look at these things, and with electrical safety/redundancy people have different points of view. My own personal values means safety comes first. This is why I got a spark to sign off my install and spoke with a mate who installs power stations for a living, i.e. knows his onions! The improvement I got with the BPS was immense, so couldn't be happier. |
|
|
|
Post by gazjam on Jul 12, 2014 10:23:44 GMT
One other point... The discussion of the safety of balanced mains transformers has been discussed to death over on Wigwam, Subjectivist, Pinkfish et al, and its the same arguments and counter arguments that come up time and time again. I'm liking how TAS is as a forum, its different. It would be a drag if we just went the same way as those others. Why do us hifi guys like repeating ourselves so much! Its only hifi ffs! always in the best possible taste... Gaz. |
|
) chat about it over on Hifi Subjectivist and I took his points on board, he DOES know what hes talking about.