Fair enough - you do have a point even though this is 'DIY' audio
I think I'll make one of these up for some fun.
I was at my traffo maker / rewinder yesterday and he's got hundreds of
transformers sitting on shelf for as long as I can remeber. I'll see if he's got a
pigeon pair of split bobbin at few hundred VA he'll let go of for a song.
T
You are old fashioned.
Now how do you plan to measure this? (Signal contamination, not age.) I do this often on many full size systems and improve my designs according to the results. So if you are running a few hundred kilowatts of amplification I have some tips for you.
Even on the bench running standard quality checks, the AC power line quality may limit the performance of the device under test from meeting the manufacturers spec.s.
I recall one arena where the signal processing equipment was so badly affected by the design and AC power line issues that I just replaced it all. Yes the gear came from a major manufacturer, still in business, but following engineering recommendations from a well known consultant. (One who I don't agree with.)
1- I don't even know if it can improve any well made power amplifier. But any system with multiple AC powered gear connected together, that I'm quite sure.
2- My words was more about an attitude that I feel sometimes not totally objective, visible antiphases. Like your remark about the price of this Monster thing.
(I hate to say this ;-(
I don't think, considering what looks to be inside, the time for the study measurements and step by step improvements and the non industrial fabrication process, this price as scandalous.
Could-you give-me the price of a specific integrated circuit including its design process, produced at less than 100 samples ?
Now, if you think that the price of this gear is too much for what it can brings, this is a very subjective point of view, that depend of your fortune and the benefit you expect. For me, out of my reach, so many things more urgent ;-)
But a typical example of a thing we can study in DIY. That i find interesting, IMHO.
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Nah Peter Walker never listened to things (or never admitted to anyway). The Jung/Didden super-regulator is slightly lower noise but I doubt I need that.
I do have a couple of 500VA toroids* and half a dozen common mode chokes that somehow never made into into blacked out range rovers. But without a repeatable measurement I can do it's all in my head as to whether that makes a difference.
In particular I would like to actually test the electrostatic shields on a couple of toroids I have above say 100kHz. But making sure experimental error isn't larger than signal being measured means it's not a 10 minute lash up for me.
Yes.And so the discussion goes round and round.
I did a bunch of experiments a while back using a 12V LA truck battery (in good condition so presumably essentially zero output resistance) to power a USB isolator/power injector pcb with on board regulation.
I also experimented with D Cell NiCd 12V battery packs (also presumably very low output resistance) to power the same USB isolator/power injector pcb.
I used the same connection cable and the same connectors on each of the batteries in order to enable quick changeover and comparison.
I got two different sounds according to the battery chemistry type.
Hints mode off.
Dan.
Post # ? Sorry I missed it. I'm on batteries for the most part like Bill, even my 12V 20W T-amp but I'm willing to put it on a wall wart and try it.
I have two problems, I'm "deaf", and what I listen to isn't "good enough" to hear the difference. I have been waiting for years for the two posses to get together for an honest no peeking session, it will never happen.
You haven't done so already.....really ?.
And what type of battery ?.
It could be that the 'music' (industrial noise 'music') that you give links to has reduced your hearing....yes, really.
Why should this be opposing 'posses'.....the mutual goal is improvement, surely.
Dan.
Funny Ed, it's always easier to chastise those whom you put as "those guys". There's the whole point one finger three coming back that folks should think really hard about.
Also, this it diyaudio, not "go to the store and buy a system worth more than my annual income." Some assembly is assumed. I can assuredly believe that a $100 boom box would benefit from line filtration as could the poorly designed high end circuits that forgo psrr for philosophy, and a mitigation of ground loops having the entire audio playback sitting behind a isolation transformer. But there are plenty of ways to deal with that in the home setting that doesn't require a $1300 box. Again, not the usual place we see isolation transformers being used.
So taking a "mid fi" setup, say the equivalent of a $200ish CDP, $500 amp and maybe equivalent value preamp/tuner from the lines of parasound or adcom (pick equivalents as you like), and the ugliest domestic power you can find, is there a difference on the amp terminals? I realize that less than the cost of a monster 7000, but humor me.
Nicest thing you've said about me for months
This is the challenge, esp if the results are to be repeatable by someone else without 200k invested in test gear.
A possible answer for the first part of the sentence you quoted could have been, "buy a meter".
For the "something" i had an idea too, but i do not dare ;-)
If you have 39.37 inches, you don't have to worry?
But if you want to measure at the limits of perception the minimum would be a good quality sound card and a battery powered computicater thingy. Then all you have to find a nice low emi location.
Perhaps, but it's also being leveraged by a number of posters above as a means to ignore posts they don't want to address, that may or may not be inconvenient to actually prove their efforts (or their expensive parts) are actually doing something meaningful.
Great, then it should be fairly straightforward to show a significant change in the output. Which, when we get to brass tacks, showing the end result has not been part the sales pitch at all. Why should I or anyone else take all these claims at word of mouth?
I'm still looking for this costed reference schematic... So, no, I don't have a "recipe".
The method of verification is what is in question, I would think it was enough that JC admits the differences disappear when he does not know what
A and B are.
See Post #5274. I have tried this but found the series inductance of the two xfomers affects the dynamics of music. I have yet to find any series L filter that does not do this. Now a big choke across the line is a different story.
Not sure where you have been looking, but I thought some pretty pictures have already posted here.
Attached is one of my old ones showing noise riding in from the AC power line while the power supply rectifier diode is conducting. If you do the arithmetic this amount of noise will increase the noise floor to a level that may be perceptible depending on the loudspeaker's sensitivity (efficiency) and the listening environment noise floor. (About 29 dB spl without any gain or power supply filter loss for a small cheap loudspeaker. 46 dB spl with a horn and 19 dB spl with a low efficiency unit.)
Yes there is filtering for the expected 120 hertz ripple but it in a lower production cost power supply is almost useless at 6,000 hertz where the hearing of humans is most sensitive.
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If the inductance is very large it will widen the rectifier pulses. But with B2B trafos you only get twice the inductance.
You do get twice the radiated flux, which would be correlated with leakage inductance.
What is the significant difference between DM filtering in the isolation trafos and splitting your cap bank into 2 banks with small resistors in between? I would think the latter approach would be more effective and economical?
You do get twice the radiated flux, which would be correlated with leakage inductance.
What is the significant difference between DM filtering in the isolation trafos and splitting your cap bank into 2 banks with small resistors in between? I would think the latter approach would be more effective and economical?
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