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McIntosh Transformer causing noise in speakers while disconnected.
- Thread starter ClassG33
- Start date
I like it when I am corrected. It means a lot to me and it should be done at every available opportunity by whomever sees fault in my ideas and comments.
I just started to read this thread and now see this was already pointed out before, sorry that I rubbed it in again..The plot thickens even further and gets more embarrassing as it goes along...LoL. It was a very long day...
It's fine. You are a professional and I know this. I admired your forthright interjection and if you where there at the time would have saved a lot of stuff from occurring.I just started to read this thread and now see this was already pointed out before, sorry that I rubbed it in again..
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It is unlikely the breaker is causing noise. Now GFCI or AFCI could be a source as mentioned by Peng. Your breakers in your breaker panel are plain breakers. However, if you have a bad or going bad GFCI in an outlet on the same circuit it might cause noise issues. I still think it unlikely, but I have run into that on two occasions.
As for your reconstituting your gear differently, am I right you are using XLR connections? Those are less likely to pick up noise though it is not impossible. Since the breaker panel is in that room, I'd keep more sensitive components away from it as much as possible. Your power amp normally would be least effected by it. So you could put it on the breaker panel side. I believe until proven wrong later today, that the most likely issue is your prior amp was damaged/defective in some way. If the new one slots in and is quiet, then you can forget about all this other stuff.
As for your reconstituting your gear differently, am I right you are using XLR connections? Those are less likely to pick up noise though it is not impossible. Since the breaker panel is in that room, I'd keep more sensitive components away from it as much as possible. Your power amp normally would be least effected by it. So you could put it on the breaker panel side. I believe until proven wrong later today, that the most likely issue is your prior amp was damaged/defective in some way. If the new one slots in and is quiet, then you can forget about all this other stuff.
After reading most of this thread I can only conclude it is caused by inductive coupling between the Amp and the coils in the crossover in the center speaker. Probably it was already concluded somewhere before, in that case I will the change the conclude in confirm.
mhardy6647
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Yes, indeed -- to quote a famous loudspeaker builder's recent posts here at ASR -- it's a "FACT" (the capitalization is all his)!Well it is what it is...
The real limiting factor for me is when the power conditioner is loaded down it becomes a voltage drop/resistive and that's a major liability.
The point about the loading effect of the conditioner is a good one -- although I really don't know how much of a factor it is IRL with a conditionar of suitable capacity(?).
I am beginning to wonder if the OP's just dealing with some crappy wiring -- although circuit breakers do go bad (BTDT, as they say) and get chattery and "flickery" and all sorts of badness (and, with the acknowlegement that @Blumlein 88 likely has far more experience with this than do I).
Here are the basic claimed specs for the Furman ELITE-15 PFi Power conditioner used by the OP. With my highlights.
It has the max of 15 Amps distributed across 13 outlets. The 3 Amps RMS reserve with 45 Amps peak (@ what time duration?) is iffy for sure for a AV system like this beasty McIntosh powered one. I think the system load presented at the Furman is considerable when the AV gear is cranked up with some heavy classical music etc and that the Furman will limit the output current causing a voltage drop on the AC supply and even for a tiny fraction of a second it still is a liability to the system. The RMS power output of the McIntosh is affected by the square of the Vpeak output of the McIntosh so any reduction could be a big deal I think. <Watts RMS = (Vpeak * 0.707) ^2 / R load>
mhardy6647
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Agreed. It's marginal at best.
Indeed (now that we're on the subject and my memory's been jogged!) don't many BIG power amps' manufacturers recommend plugging directly into the wall?
I think Mac may be one of them, in fact.
The OP may want to plug all of the little gizmos in his system into the power sweeterner and mainline the big ol' Mac amp -- right into the wall outlet.
I would think 20 amp circuits would be better for that A/V setup anyway -- if you don't have 20 amp circuits in there already, @ClassG33
Indeed (now that we're on the subject and my memory's been jogged!) don't many BIG power amps' manufacturers recommend plugging directly into the wall?
I think Mac may be one of them, in fact.
The OP may want to plug all of the little gizmos in his system into the power sweeterner
and mainline the big ol' Mac amp -- right into the wall outlet.I would think 20 amp circuits would be better for that A/V setup anyway -- if you don't have 20 amp circuits in there already, @ClassG33
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- Thread Starter
- #430
The Furman has two High Current outlets, but it does not tell you exactly how much more amperage this supports. In my opinion, and I am very open to being wrong on this, I believe amp companies say to go into the wall so people do not make the mistake of using a power center or surge protector that doesn't support High Current. This is most likely just a liability tactic for people who do not read manuals and just buy stuff online, or in the case of salespeople who don't know any better. Truthfully I am scared as he'll of the idea of not having any protection between the wall and nice gear.
- Thread Starter
- #431
No 20 amp that I could use unfortunately, but I hear you. When I am designing low voltage for new builds, and I'm working with their electricians, I always put it in writing several times that the Mech. Room needs dedicated 20 amp circuits for the racks. I also make them add dedicated circuits for subwoofer locations for people doing line Arrays or just multi sub systems. My Panamax has a amperage reader, and on this system, I've never exceeded 6amps that I have noticed, even when pushing my Arcam AVR20 to its limits. Although I plan to have these converted to 20 amp circuits when I add 2 subwoofers later this year .Agreed. It's marginal at best.
Indeed (now that we're on the subject and my memory's been jogged!) don't many BIG power amps' manufacturers recommend plugging directly into the wall?
I think Mac may be one of them, in fact.
The OP may want to plug all of the little gizmos in his system into the power sweeterner
I would think 20 amp circuits would be better for that A/V setup anyway -- if you don't have 20 amp circuits in there already, @ClassG33
Try without the Furman and with the original AC cables delivered with your products.
Do you have proper grounds on your outlets ? ( can US outlets be without ground ? )
US power cables only fits one way into the socket is it so ? Polarised plugs I think it’s called .
Are hot and neutral wired correctly in your outlets ? No DIY electrical work done in your house ?
A hot/neutral mixup may not be a danger for the equipment but it can affect the stray magnetic field of the transformers in power supplies .
Do you have proper grounds on your outlets ? ( can US outlets be without ground ? )
US power cables only fits one way into the socket is it so ? Polarised plugs I think it’s called .
Are hot and neutral wired correctly in your outlets ? No DIY electrical work done in your house ?
A hot/neutral mixup may not be a danger for the equipment but it can affect the stray magnetic field of the transformers in power supplies .
Also looked at the spectrum in more detail:
Its indeed a nice grid of 60Hz odd harmonics.
My guess: interaction of the rectifier with the transformer that the transformer sends out as a strong EM field.
Its indeed a nice grid of 60Hz odd harmonics.
My guess: interaction of the rectifier with the transformer that the transformer sends out as a strong EM field.
I was very suspect of the 40 Hz fundamental frequency hypothesis. That if it was correct would go way above my headspace into territory unknown for me but I went with it to see what happens. The same for the hypothesis of the RF output modulation stuff. Too complex and too many unlikely things combined to result in such a effect. Thanks for the test results indicating 60 Hz.
Cheers.60.07 Hz to be more exactI was very suspect of the 40 Hz fundamental frequency hypothesis. That if it was correct would go way above my headspace into territory unknown for me but I went with it to see what happens. The same for the hypothesis of the RF output modulation stuff. Too complex and too many unlikely things combined to result in such a effect. Thanks for the test results indicating 60 Hz.
@Hayabusa
So if 60.07 Hz then why would the software trigger on a ~40 Hz slope?
Is it poor slope/trigger levels and poor software programming or simply not reliable?
I am accustomed to analogue instrumentation where the trigger level is adjustable by slope or voltage and these issues like with the software simply do not exist.
So if 60.07 Hz then why would the software trigger on a ~40 Hz slope?
Is it poor slope/trigger levels and poor software programming or simply not reliable?
I am accustomed to analogue instrumentation where the trigger level is adjustable by slope or voltage and these issues like with the software simply do not exist.
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