As an aside, I find it unbelievably ironic that a site such as this, one dedicated to audio, can contain so much "audiophile bashing". The NCore thread is particularly vulgar in this respect. Let's look at a sensible definition of "audiophile"...Wiki's definition would seem rather reasonable: "a person enthusiastic about high fidelity sound reproduction." That's you and me. This site is for people enthusiastic about audio reproduction and I doubt many fall into the "okay is good enough" camp. We are all audiophiles. Were we not we wouldn't be spending time here.
Yes, we are both audiophiles in the sense of that definition. I, for one, am not bashing audiophiles, I am bashing audiophile folklore, a rather different thing. I am of the opinion that good sound reproduction is achieved through engineering (a form of applied science) rather than hearsay, superstition, voodoo and dogma. There is nothing magic about audio technology - it is just technology, a result of science and engineering.
The NCore thread is, as you point out, a good example - the amount of false information, hearsay and "audiophile religion" has been particularly vulgar in this respect.
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Good. It's just that many of your posts in this regard appear to bash the collective noun rather than selective examples of behaviour. Having read every post in the first 550 plus pages of the Ncore thread I would say there's more "audiophile bashing" and "Bruno idolisation" than "audiophile religion". Anyway, I think one can come to the table and either trash someone's goals or help them reach them, the latter being preferable in my mind. Carry on.
This is getting completely off-topic for this thread, but I went back and had a look at the last series of exchanges in the Ncore thread. There the OP asked for instructions for bridging two nc400's. As it turned out, he was severely misinformed by audiophile hearsay and hadn't done his numbers. Yes, we did provide him with a pointer to instructions, but we also pointed out the fallacy in his assumptions, and why a) he wouldn't gain any benefit from the bridging configuration (as his concern wasn't additional power but current drive capability) and b) that the nc400's, being specified down to a 1 ohm load, were more than capable of driving his "demanding" (down to 3 ohm) speakers.
Now, one could view that as trashing someone's goals - if the goals are to have the warm, fuzzy feeling of having followed all audiophile superstition and voodoo, and feeling you have the best system in the world. But on the other hand, you can be of the opinion that we helped him to reach the goal of enjoying exactly the same sound quality without useless waste of money and hardware. In the end, it is of course up to each of us to make those choices.
Marce, I've read and benefitted from your experience on this forum - thank you. I am also one of those who has built a multiple-rail linear supply to replace the atx psu for my audio pc. Further, I have experimented by removing the power to the ram and feeding regulated lifepo4 power directly to the ram, bypassing the usual supply. This gave a further benefit to the sound although not of the magnitude that changing the psu did.
I am not trying to pick a fight but keen to understand why. If we set aside the possibility that I am deluding myself or that I am lying - I can't help with the latter but regarding the former, I tested the playback on a couple of friends with a similar preference. I also suggest that the switching/linear argument is avoided as I was using components that I had to hand and realised that I could build a better linear than switcher with them.
If the ram just does it's job and clearly can't account for the difference in sq, could it be that something downstream from the ram is affected by the 'purer' power or perhaps the higher esr?
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Was the setup a proper double-blind, or could your friends see you?
There is a very good reason proper lab listening test protocols prescribe double-blind ABX. I have been surprised by how easily the person running the test communicates (unconsciously) his/her preferences to the test subjects...
Without proper measurements of the PCs noise spectrum we cannot really understand what is going on, just guess....
As I have said many times the noise in a PC is not just from the SMPS, a lot of noise is generated by the circuitry operating, this is called simultaneous switching noise. The best way to get a handle on this is to read up on the differences between DDR2 and DDR3, specifically how they have spread the switching between banks of RAM to limit the noise, this technique is also employed in SMPS, call spread spectrum switching.
Personally I would not recommend playing with the RAMs power supply, unless you fully understand the implications. Now you said it gave further benefits to the sound, this could be because you are actually increasing the noise floor not reducing it adding texture to the sound further down the line, again only very careful measurements with high GHz scopes etc will give a true picture of what is going on, I do get to see PCB designs and systems I have worked on to this level as I tend to work mainly on rather more sensitive stuff, such as now where I am having to drive from Blackburn every week to play about with some PCB designs at Cobham Flight refuelling. I have also worked on a lot of communications systems where again we investigated noise and noise related problems to the nth degree, as well as doing a few SMPS's to replace linear supplies in a mil trainer jet.
As I have said many times the noise in a PC is not just from the SMPS, a lot of noise is generated by the circuitry operating, this is called simultaneous switching noise. The best way to get a handle on this is to read up on the differences between DDR2 and DDR3, specifically how they have spread the switching between banks of RAM to limit the noise, this technique is also employed in SMPS, call spread spectrum switching.
Personally I would not recommend playing with the RAMs power supply, unless you fully understand the implications. Now you said it gave further benefits to the sound, this could be because you are actually increasing the noise floor not reducing it adding texture to the sound further down the line, again only very careful measurements with high GHz scopes etc will give a true picture of what is going on, I do get to see PCB designs and systems I have worked on to this level as I tend to work mainly on rather more sensitive stuff, such as now where I am having to drive from Blackburn every week to play about with some PCB designs at Cobham Flight refuelling. I have also worked on a lot of communications systems where again we investigated noise and noise related problems to the nth degree, as well as doing a few SMPS's to replace linear supplies in a mil trainer jet.
Very cool!
(Cobham were the guys who developed the probe and drogue air-to-air refuelling technology back in the day)
Yep, having to spend summer in a Hotel in Bournemouth and drive to Windborne every day to play with PCBs. I also worked for Cobham at Blackburn and was in control of the rigid PCB designs for this:
http://www.northropgrumman.com/Capabilities/ANVIC5/Documents/vic5.pdf
Also work down at Racal Acoustics doing the headphone stuff to go on the boxes. I do get to design boards for some cool stuff, but spend a lot of my year away from the wife and kids, and it is starting to put a strain on life..... Trouble is these sort of firms don't like their data floating about all over the place so its generally on site work. This is where I have learned a lot about noise, EMC etc due to the stringent levels that have to be reached for this sort of gear. Interestingly done powered headsets with the switchmode on the same board as the headphone electronics in the earshell, no problems with sound quality, noise etc, which is why sometimes I believe a lot of the fear of SMPS's is unfounded, thought it was a good layout
(I did it...)
http://www.northropgrumman.com/Capabilities/ANVIC5/Documents/vic5.pdf
Also work down at Racal Acoustics doing the headphone stuff to go on the boxes. I do get to design boards for some cool stuff, but spend a lot of my year away from the wife and kids, and it is starting to put a strain on life..... Trouble is these sort of firms don't like their data floating about all over the place so its generally on site work. This is where I have learned a lot about noise, EMC etc due to the stringent levels that have to be reached for this sort of gear. Interestingly done powered headsets with the switchmode on the same board as the headphone electronics in the earshell, no problems with sound quality, noise etc, which is why sometimes I believe a lot of the fear of SMPS's is unfounded, thought it was a good layout
(I did it...)Double cool - I currently am restoring some of the old Racal, Plessey and Watkins-Johnson cold war electronic warfare equipment, and of course familiar with Clansman etc., but not really up to date with the latest generation of equipment.
Yes, that sucks!
Indeed. Was involved with some of the early TEMPEST stuff...
Interestingly done powered headsets with the switchmode on the same board as the headphone electronics in the earshell, no problems with sound quality, noise etc, which is why sometimes I believe a lot of the fear of SMPS's is unfounded, thought it was a good layout
I agree. The fear of SMPSs is mostly totally irrational, based on the dirt cheap wall wart ones. A well designed SMPS can be quieter than a linear supply, and superior in all other respects too.
It maybe OK electrically but they are also superior in premature dying. If it is not a cap then it is something else that breaks. I use SMPS a lot but this still is a drawback. They don't last as long as the old transformer, rectifier, cap power supplies.
Often the SMPS being replaced is something like a PicoPSU. Why not build a good linear PSU and see? Nothing wrong with people wanting to give this a go. I would rephrase it as "someone wanting to improve the PSU they are using and a linear one is likely easier to design for quality than an SMPS." And before you say "why don't you buy XYZ?" let's remember this is DIY. BTW I'm not even sure the OP is listening here anymore...
Well, they are more complex. But I have had my fair share of electrolytics in linear suppies drying out and diodes failing...
Again I think this is down to bad design and choice of components, in the above mentioned types of designs you have to de-rate components to get decent MTBF figures, CAPS MIN 50% on voltage, resistors again less than 50% on power rating. A lot of commercial gear doesn't have to work without failure and is built to a price with caps barley rated at their working voltage.
This is not a problem for DIY designs, you can de-rate your components and get better reliability. 15 years is usually a min time for operation of a lot of this gear. And cost is a concern these days, the IPC did a big thing about cost reduction for Mil design around 2011.
Had a chat with a colleague who works on the assembly side of electronics regarding SMPS reliability...
He said figure how many products there are with SMPS's produced and in use, then figure the percentage failure...it is actually no worse than linear, just the number of failures is higher due to the number of products out there with SMPS's, products that we wouldn't have if we still had linear supplies only. And he seconded my view that they are used in products that require the ultimate reliability so doesn't agree that they are any less reliable, if competently designed.
The one caveat is we now have access to very cheap goods via ebay and such like, some of these are decent well manufactured, some are built and sold to a cost...I have bough some photographic equipment that falls into this last category, such as light stand adaptors for flash guns, very cheap both in cost and quality, such things as tightening screws going directly into plastic...the same happens with electronic goods.
He said figure how many products there are with SMPS's produced and in use, then figure the percentage failure...it is actually no worse than linear, just the number of failures is higher due to the number of products out there with SMPS's, products that we wouldn't have if we still had linear supplies only. And he seconded my view that they are used in products that require the ultimate reliability so doesn't agree that they are any less reliable, if competently designed.
The one caveat is we now have access to very cheap goods via ebay and such like, some of these are decent well manufactured, some are built and sold to a cost...I have bough some photographic equipment that falls into this last category, such as light stand adaptors for flash guns, very cheap both in cost and quality, such things as tightening screws going directly into plastic...the same happens with electronic goods.
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So, funny thing. I had subscribed to the thread to get email notifications whenever someone posted, but after my last reply I didn't receive anything until yesterday...
I got the email and figured someone replied out of the blue, only to find there were 4 pages and a full discussion going on. Thanks a lot, guys, I got a few things from what you guys said :-D
And yes, from that post you may have gathered I don't know the ins and outs of transformers. I'd say I know just enough to confidently say more than zero, but that's about it. That's what brought me here, amongst other places
Just to be clear, I'd never commit to potentially electrocuting myself unless I had a pretty damn good idea about what I was dealing with. And a few posts on a DIY site aren't all it takes for me to run out and think I'd be able to handle laying out or playing with a very much lethal transformer.
I've read up on them a bit, and my understanding is developing, but you don't know what you don't know until you know. Right?
As for this situation and its status, since April bigger things have popped up and I'd put this on the back burner. Part of moving it to the back burner came from when I'd also looked into more about this on the AMB forums with trying to use a 3 Sigma 11s to provide the 3 rails. This lines up with me not knowing what caps or op-amps or rectifiers I'd be using. Going with a kit like that seemed like a quick root to getting this moving, but I was informed that the Sigma 11s max out around 4amps (IIRC) and they also can't provide below 5v, so now way to make a 3.3v rail from one. At that point I put this on pause because I didn't know where to go. I kinda figured it was dead in the water :-/
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