And the transformer.
As usual snide and wrong. I'll assume you are refering to the transformer inside the unit, not the distribution transformers that contribute to the low supply resistance.
A 600 watt capable power transformer will an equivalent resistive loss of .25 ohms typical on the primary. That is a fixed resistance and doesn't change with load.
In a transformer design typically half the losses are magnetic and half resistive. As the transformer in an audio power amplifier is sized for maximum output and normal maximum has at least 10 dB of headroom losses are much less from the resistive component.
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Not quite. IEC and ANSI correspond. But of course the transmission distances are much shorter in Europe.
According to your numbers, no.
Also, try using impedance instead- that's probably a bit more honest.
In a 600 watt amplifier with a 2.5 amp time delay fuse I would expect .08 ohms of modulation on a fixed source resistance about .18 ohms and .25 for the transformer primary. So actually no change at all in the output voltage as the transformer probably runs in light saturation. Other wise including all of the fixed transformer losses around a 10% source resistance modulation
BTY don't mention to SY the the line resistance with a warm fuse is greater than the transformer's primary resistance. I think he is using his fingers to count and to do this kind of arithmetic he would have to cut off bits of his fingers. Also don't clue him in the NEC refers to resistance as there ain't much difference at 60 hertz and ohm is the unit for both.
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Nice bait and switch.
And you sorta neglected an important term in the impedance. But you knew that.
Nice bait and switch.
And you sorta neglected an important term in the impedance. But you knew that.
Well SY again you make nonsense claims. The thread started out asking about the fuse holder for a 600 watt amp. Unlikey it is a 5 amp fuse. Same ratings for the transformer I cited for a 600 watt amplifier. Then the other main issue is that fuses modulate resistance value under load and no other resistance does that.
But do let me know when you measure the AC power line impedance. Then tell me the difference between that and the resistance. Then we can talk about what inductance vs resistance has to do with transformer function.
Then we can do a double blind test to see if ...
The start up surge is a function of transformer design and load capacitance. One cheap way to get high peak watts is to use a low current capacity transformer and lots of capacitance. That would not have a large turn on surge but is really used in cheap units.
Toroid transformers often have a high surge current at turn on depending on when in the power cycle they were turned off.
Sizing a fuse to never fail during turn on but to always blow upon a fault is actually quite tricky.
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SY more nonsense, do you ever run out? Apparently you don't even know Ohms law. Remember when you didn't know the definition of capacitance.
What the F do you think we have been discussing.
But why don't you give us your bona fides.
Write the circuit equation for the power circuit under discussion.
What is the permissible range of AC line voltages in the US?
What is the standard current rating for a single family residence?
What is the maximum length allowed for residential branch circuit wiring?
What is the cold resistance of 1/2, 1, 2, 5 and 1O amp 3AGC fuses and how does that differ between fast blow and delay fuses?
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It should be noted that, as the OP has spotted in his junk box, there are some nasty panel mount fuses around. In domestic service you generally wont see a problem, but in my youth have seen plenty of lighting rigs and PAs where due to number of cycles (grunts blowing fuses) and physical abuse (grunts again). the cheaper ones can lose contact. I don't have numbers so this is personal paranoia, but would not use the bayonet type on a personal build. IEC connectors with integral fuse holder(s) is a very good compromise for domestic use IMHO.
UK is of course strange as we have this damn fool plug that has a fuse in it. I have asked the wife if I can upgrade the living room to 16A commando sockets. She is not buying
UK is of course strange as we have this damn fool plug that has a fuse in it. I have asked the wife if I can upgrade the living room to 16A commando sockets. She is not buying
Well folks... it HAS been done (which one was it, avclub.gr or avsite.gr ? can't remember, it was some years ago).
Small group of "testers", 4 or 5 I think, so the statisticians amongst you won't be satisfied, I know
Anyway:
To minimize the time interval, they used a diy Y-connector to the amp, without turning the gear off. Both power cords plugged into the wall sockets, only one to the Y-connector.
While music was playing, a guy plugged in the other power cord and immediately pulled out one of the two.
The testers could not see which one, and they only had to report if they thought the power cords had been swapped or not, regardless if the perceived change in the sound was for the better or worst (but to make things more interesting, they could take a note if it was "better" or not)
So, if someone noticed a "change" with no cable swap, he was obviously guessing. If actually there was a cable swap, maybe he wasn't guessing, but then again, maybe he was...
The comparison was extreme: same length of El-cheapo against an Ultra-Expensive one.
Ta-Daah ! the results :
Well, most of them - two or three, can't remember if they were 4 or 5 in total - gave correct answers by a small margin of 6-4 . I think one achieved a 7-3.
And yes, they all did think the expensive cord sounded a liiiiitle better, but the difference was so subtle AND uncertain, no way would they pay the huge price difference.
One of them admitted he could not spot any change, and was only guessing all the time. And his results were 5-5
And now the best part :
The remaining one.. was one-hundred-per-cent incorrect !!!
Oh, yeah baby, ten out of ten!
He spotted all the actual cable swaps as bluffs and all the non-changes as changes. Not a single side-step, rock solid consistency!
Golden ears in reverse, or GOLDEN EARS and pulling their leg ???
Boy, do I love cable tests, threads, disputes, and flames
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Mmmm, to be honest, I am reluctant to take sides on this one.
The guys who spotted differences came from the diy community of the forum, and you could rather call them skeptics, than audiophiles. According to their sayings, they concentrated on pretty precise minimal fragments of the recording to spot changes.
The "reverse golden eared" also admitted he could hear no difference and was just tossing coins when answering (Lotto suits him better than audio, I guess)
So for me, it's an insignificant sample who nevertheless did pick the expensive cord, be it by luck or not.
Waiting for ten more similar tests - or a big one - to take sides
The guys who spotted differences came from the diy community of the forum, and you could rather call them skeptics, than audiophiles. According to their sayings, they concentrated on pretty precise minimal fragments of the recording to spot changes.
The "reverse golden eared" also admitted he could hear no difference and was just tossing coins when answering (Lotto suits him better than audio, I guess)
So for me, it's an insignificant sample who nevertheless did pick the expensive cord, be it by luck or not.
Waiting for ten more similar tests - or a big one - to take sides
I think you should seriously reconsider that SAFETY fuse bypass thing...if there should be a fire, you could be held personally responsible for property damage, injuries or deaths.
Oh, and your claim that the power fuse affects the sound of you amp...my question would be, what's wrong with that amp?
Mike
So in operation, what is the range of voltage drop across the fuse? What is the resulting voltage drop across the transformer? How do those quantities compare? Now given the change in line voltage seen by the transformer vs current, how does that compare with the regulation of the xformer? I mean to say, transformer secondary voltage will vary something on the order of 10% between unloaded and max rated current; what percentage change in primary voltage results from fuse heating in the same conditions? Put yet another way, how does the secondary dV/dI compare with or without a fuse?
Is your magic 0R25 meant to represent the DCR of the primary? Since we don't operate transformers on DC I'm not sure how that's relevant. Surely you are not suggesting that the transformer primary on a 600W amplifier is drawing 480A on a 120V line voltage? If so you need a much bigger fuse.
I see SY is fielding the abuse usually reserved for me. Once I have a setup that works for a week or so I solder #10 buss wire across all fuse positions. I say F fuses.
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