ttocs
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I always have a wonderful time, wherever I am, whomever I'm with. (Elwood P Dowd)
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Post by ttocs on Oct 27, 2022 8:32:23 GMT -5
The TV developed a high pitch whine that came from the upper right side. My dad would get up and pound the side of the TV with his fist, and the whine would stop ... for a while, anyway. Yeah, a transformer. The TV case was metal and was eventually dented in about an inch from the pounding. So, just a suggestion  Well, in this case, the transformer is going to do what it wants to do regardless of being attached to the amp case or not. It's still making the noise, but it's not transmitting all of it to the metal case, and the amp feet aren't transmitting it to the shelf. As far as I can determine, the tranny emits two noises, an extremely faint hum that can only be heard when I place my ear against the amp case. And then there's the geiger counter noise, a ticking sound, which doesn't happen all the time so the DC Offset theory doesn't fit. This amp powers the 4 Surrounds and 4 Tops, so when there's no audio activity the amp noise is either silent or almost silent, but if the speakers are very active and loud the amp noise is louder. |
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Post by AudioHTIT on Oct 27, 2022 10:23:34 GMT -5
The TV developed a high pitch whine that came from the upper right side. My dad would get up and pound the side of the TV with his fist, and the whine would stop ... for a while, anyway. Yeah, a transformer. The TV case was metal and was eventually dented in about an inch from the pounding. So, just a suggestion Well, in this case, the transformer is going to do what it wants to do regardless of being attached to the amp case or not. It's still making the noise, but it's not transmitting all of it to the metal case, and the amp feet aren't transmitting it to the shelf. As far as I can determine, the tranny emits two noises, an extremely faint hum that can only be heard when I place my ear against the amp case. And then there's the geiger counter noise, a ticking sound, which doesn't happen all the time so the DC Offset theory doesn't fit. This amp powers the 4 Surrounds and 4 Tops, so when there's no audio activity the amp noise is either silent or almost silent, but if the speakers are very active and loud the amp noise is louder. This Geiger counter noise wouldn’t be the ticking heat expansion noise some transformers make when their mounting screws are too tight? |
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ttocs
Global Moderator
I always have a wonderful time, wherever I am, whomever I'm with. (Elwood P Dowd)
Posts: 8,154
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Post by ttocs on Oct 27, 2022 11:07:03 GMT -5
Well, in this case, the transformer is going to do what it wants to do regardless of being attached to the amp case or not. It's still making the noise, but it's not transmitting all of it to the metal case, and the amp feet aren't transmitting it to the shelf. As far as I can determine, the tranny emits two noises, an extremely faint hum that can only be heard when I place my ear against the amp case. And then there's the geiger counter noise, a ticking sound, which doesn't happen all the time so the DC Offset theory doesn't fit. This amp powers the 4 Surrounds and 4 Tops, so when there's no audio activity the amp noise is either silent or almost silent, but if the speakers are very active and loud the amp noise is louder. This Geiger counter noise wouldn’t be the ticking heat expansion noise some transformers make when their mounting screws are too tight? No. When I removed the toroidal transformer center bolt I had the opportunity to turn the amp on while the tranny was lifted a bit with some extra rubber beneath it, and the noise continued but was much quieter. I do believe it's an expansion noise of sorts that, apparently, toroidal transformers are known to make, except that the huge one in my Krell amp is silent, but then that amp cost 12 times what the BasX amp cost. The noise level I heard last night is totally fine with me. I had to turn off the sound and turn off the Dyson fan to be able to hear the amp noise. |
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Post by leonski on Oct 27, 2022 16:59:00 GMT -5
The high pitched whine? (not WINE) was the flyback........
My brother and I bought our parents an EARLY Sony Trinitron in 19" and the cart to go with it.
That TV was perfect until it was too far gone to fix......Mechanical tuner parts were Unobtanium
and I suspect the expertise to actually DO the work was also gone.....
BEFORE the Zenith Space Command remote? We had a TV which used a GI style right angle FLASHLIGHT.
This was also a Zenith set and you had 4 places to shine the light,.....
Later we DID have the Space Command remote. NOTABLE for NOT needing batteries. A little spring loaded
hammer struck a tuning fork......!
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Post by leonski on Oct 27, 2022 17:04:04 GMT -5
An experiment?
Get a Stainless Hose Clamp to fit......
And a piece of the densest elastomer you can find........A thick inner tube may be good for 'test'.
cut a strip the length of the Circumference of the Tranns and 1" wide at the most.
CLAMP it......Give it a good 'squeeze' and It would not surprise me to learn the toroid was now dead silent.....
If this sort of works? Try a 2nd layer of rubber........You got NOTHING to lose....
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ttocs
Global Moderator
I always have a wonderful time, wherever I am, whomever I'm with. (Elwood P Dowd)
Posts: 8,154
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Post by ttocs on Nov 1, 2022 9:27:12 GMT -5
I was wrong. I'm never shy to say it when it happens. It means I've learned something.
It's not the transformer making the ticking noise, it is the fans. Yes, they are not spinning when it happens, but that's because they are getting a low enough amount of power to juuuust barely make them react internally but not enough to spin, just over the threshold of the low temp setting, according to service. But the fans will spin when really needed, which in my case has never happened yet. When I had the top off I measured the temperature of the heat sink and at the highest volume level, listening to music in All Stereo, with the Fronts turned off so only the 8 channels on the BasX A-800 were in operation, the temperature never was more than 90ºF at the hottest spot on the heatsink.
So I told service thank you, but I'm not sending it in for service. The noise is less than when I had the amp on the padded shelf in the front of the room, since adding the extra rubber under the transformer, so now I have to shut everything off to hear it. I lived with it for 2-1/2 years up to now, so it's fine with me forever.
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Post by leonski on Nov 1, 2022 16:40:43 GMT -5
Man, I LOVE IT when somebody gets to root cause. I don't care if my guess was wrong.....YOU got to it!
My old Carver Cube made a little putt-putt noise. Something power supply related.....It was an odd design with a big Choke (fist size) and some other goodies.
It was meant to turn on and off IN TIME TO THE MUSIC so it stored very little energy except in the magnetic field of the choke......No large 'storage' capacitors.....
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Post by drumace on Nov 6, 2022 13:00:52 GMT -5
Disclaimer- I did not read the entire thread, but I had the exact same issue on my A-500 I bought new from Emotiva.
Since the amp always stays cool, I decided to unplug those fans and that’s it, problem gone. I believe the root cause is a wrong calibration of these fans for when they should REALLY kick in. I have sufficient clearance between my components and they’re all in the open space so heat it not a problem.
Reading reports about this issue on the newer generation amps means to me that the issue is carried on rather than fixed.
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Post by leonski on Nov 6, 2022 15:30:18 GMT -5
Silly Question?
Are the fans simpy 'on' or 'off'? Or is there a throttle / control to speed?
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Post by drumace on Nov 6, 2022 15:45:20 GMT -5
Silly Question? Are the fans simpy 'on' or 'off'? Or is there a throttle / control to speed? There’s no switch, just 2 connectors (assuming one for each fan) that you can disconnect (not sure if that voids the warranty though but my amp is 5 y/o). |
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Post by leonski on Nov 6, 2022 16:58:00 GMT -5
So? I you turn it UP all the way with a SunLamp on it and sitting on a heating pad, the fans run the same as they do....at idle?
I just don't know that IF I thought a fan was necessry, that it would't have some kind of temp control on-off or even some kind of proportional control......
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Post by oidarnam on Nov 6, 2022 20:46:55 GMT -5
So? I you turn it UP all the way with a SunLamp on it and sitting on a heating pad, the fans run the same as they do....at idle? I just don't know that IF I thought a fan was necessry, that it would't have some kind of temp control on-off or even some kind of proportional control...... I don't have a BasX amp (yet  ), but you are asking if the fan is either on or off or has variable speed control based on the temperature? Good question, although the simplest implementation is just on or off. I would think, however, that the fans are in there for a good reason and come on when they do for a good reason too. Maybe at modest output levels, fans are unnecessary. One would hope that whether or not the fans are connected, the thermal protection would kick in and shut down the amp before irreparable damage is done.
I'm guessing the next generation of BasX amps will have a SMPS (like the A2m), but unlike the A2m, maybe the extra weight budget would allow for passive cooling so the fan(s) can be eliminated. There are other amps in this class that are passively cooled, I believe.
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Post by leonski on Nov 7, 2022 14:20:04 GMT -5
So? I you turn it UP all the way with a SunLamp on it and sitting on a heating pad, the fans run the same as they do....at idle? I just don't know that IF I thought a fan was necessry, that it would't have some kind of temp control on-off or even some kind of proportional control...... I don't have a BasX amp (yet ), but you are asking if the fan is either on or off or has variable speed control based on the temperature? Good question, although the simplest implementation is just on or off. I would think, however, that the fans are in there for a good reason and come on when they do for a good reason too. Maybe at modest output levels, fans are unnecessary. One would hope that whether or not the fans are connected, the thermal protection would kick in and shut down the amp before irreparable damage is done.
I'm guessing the next generation of BasX amps will have a SMPS (like the A2m), but unlike the A2m, maybe the extra weight budget would allow for passive cooling so the fan(s) can be eliminated. There are other amps in this class that are passively cooled, I believe.
I don't get it, either. Just how expensive IS aluminum heat sinking? Compared to fans and some additional circuitry? |
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), but you are asking if the fan is either on or off or has variable speed control based on the temperature? Good question, although the simplest implementation is just on or off. I would think, however, that the fans are in there for a good reason and come on when they do for a good reason too. Maybe at modest output levels, fans are unnecessary. One would hope that whether or not the fans are connected, the thermal protection would kick in and shut down the amp before irreparable damage is done.