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A couple of weeks ago, I picked up a used Dayton SA1000. It was extremely quiet (no humming, buzzing or any other sounds) when I got it, and for the first week it remained that way. Then it started humming quite noticeably (and the hum is amplified by the driver).


(By comparison, the other SA1000 I have is still extremely quiet.)


Having run a bunch of the usual tests on it to rule out other problems (like ground loop), I'm certain it's a problem with the amp itself. I read somewhere - regarding a different amp - that defective or worn "filter caps" may be to blame and that these usually can be replaced.


Has anyone ever replaced filter caps on an SA1000? If so:

- could you please indicate which parts you used as a replacement;

- whether a relative novice like me (with some, but not a lot, of soldering experience) could do the repair himself; and

- how well it worked out?


Thanks!
 

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I know with some of the Dayton amps if you use one of those 3 prong to 2 prong grounding adapters it will get rid of the hum. It worked on my SA240.
 

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Thanks for the reply. I'm pretty sure it's not a ground loop issue, because it was dead quiet for the first week I had it in my set-up, and then all of a sudden it started humming, despite nothing new plugged into or unplugged from my system, or anywhere else in the house.


(I had a humming issue with the very first SA1000 I brought into my house, a couple or so years ago. I tried a cheater plug (actually a cheater cord) work-around, but it didn't do anything. I had the amp replaced shortly thereafter and I've never had an issue with the replacement.)


Last weekend I ordered a Monster PowerCenter HTS1600 - because it was on sale for $149 ($100 off) at FutureShop - just to see, risk-free, what it might do for the hum. What it did was attenuate it quite a bit. It didn't eliminate it, but it made it significantly quieter.


That said, my other amp - which was plugged directly into an outlet, and not into the HTS1600 - was still dead quiet. (Which is how the "new" amp was for the first week I had it.)


So...what does this mean? Does this indicate that maybe it is a ground loop after all, or is a ground loop still ruled out? Or does it just mean that the HTS1600 somehow massages the S:N ratio down to an acceptable level, but that a bum capacitor might still be the most likely culprit?


Thoughts/comments are appreciated. Thanks!
 

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Easy way to know if it's a ground loop or bad filter caps....simply take the amp to another outlet and connect a speaker to it. Turn on the amp with no input signal and check for hum at all ranges of the volume know.
 

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I had that same amp and it went bad in 3 weeks. Send it back and buy a Crown or Berhinger. Also using a cheater plug can be a safety hazard!
 

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Discussion Starter #7
No can do. I bought it used off a ChaseHT forum member who - just to be clear - sold it to me in 100% working order.


I've contacted Dayton to inquire about filter cap replacement. I need to know which part(s) to remove and the exact spec of the replacement part(s). Hopefully they'll be able to help out.
 

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Quote:
Originally Posted by eljaycanuck  /t/1492651/fixing-a-dayton-sa1000s-hum#post_23793622


Thanks for the reply. I'm pretty sure it's not a ground loop issue, because it was dead quiet for the first week I had it in my set-up, and then all of a sudden it started humming, despite nothing new plugged into or unplugged from my system, or anywhere else in the house.


(I had a humming issue with the very first SA1000 I brought into my house, a couple or so years ago. I tried a cheater plug (actually a cheater cord) work-around, but it didn't do anything. I had the amp replaced shortly thereafter and I've never had an issue with the replacement.)


Last weekend I ordered a Monster PowerCenter HTS1600 - because it was on sale for $149 ($100 off) at FutureShop - just to see, risk-free, what it might do for the hum. What it did was attenuate it quite a bit. It didn't eliminate it, but it made it significantly quieter.


That said, my other amp - which was plugged directly into an outlet, and not into the HTS1600 - was still dead quiet. (Which is how the "new" amp was for the first week I had it.)


So...what does this mean? Does this indicate that maybe it is a ground loop after all, or is a ground loop still ruled out? Or does it just mean that the HTS1600 somehow massages the S:N ratio down to an acceptable level, but that a bum capacitor might still be the most likely culprit?


Thoughts/comments are appreciated. Thanks!

Could be a few things, but you haven't clarified the conditions of the hum. Does it hum with no RCA connection into the amp but connected to the speaker? With no RCA connection does the hum change if you raise or lower the volume? If you disconnect the speaker level output do you hear any mechanical hum from the chassis? I have seen noisy transformers/power supplies in a few cases or it could be other electronics in the power supply.
 

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Discussion Starter #9
Hi, Mark. Thanks for chiming in.

Quote:
Does it hum with no RCA connection into the amp but connected to the speaker?
Yes.
Quote:
With no RCA connection does the hum change if you raise or lower the volume?
Yes.
Quote:
If you disconnect the speaker level output do you hear any mechanical hum from the chassis?
Yes.
 

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Discussion Starter #11
Well, I brought the amp in on October 18th and I'm still waiting for a definitive diagnosis. So far, I've been told it's been tested, it's been misplaced, it's been re-tested, it's a mechanical vibration, it's not a mechanical vibration and they don't hear anything. *sigh*


I visited the shop a couple of weeks ago and the technician demostrated that he couldn't hear the hum: He hooked the amp up to a small (maybe 4") speaker tucked way under his workbench, plugged in an audio source and started blasting music. (WTF?!)


After turning off the music and pointing out the hum, I re-explained everything for the nth time and he said he'd have a look at it again. (He said he thinks it might be the filter capacitors.) This coming Friday, I'll drop by the shop to see how they're doing.


WHAT I'M WONDERING:

- The amp I brought in was silent when I got it, and two weeks later it started humming.

- The other SA-1000 I have was silent for over two years and it has recently started humming.

- My AVR and Emo amp don't hum, however, and neither did my previous AVR.


1. Is it possible that the filter caps on the Dayton amps are of such poor quality that they fail in the course of a few years? (The tech was surprised when I told him the amps were between 2-5 years old. He thought they were at least 10 years old.)


2. Is it possible that the "quality" of the electricity in my house* is damaging the filter caps on the Dayton amps? If 'yes':

- What can I do to improve the quality of the electricity?

- Why wouldn't the AVR and Emo amp also be affected?


(*I actually had an electrician inspect my electrical panel about 2-1/2 years ago just to make sure everything was in order and it got a clean bill of health.)


Thanks for your thoughts/comments.
 

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Hum is a product of the 60-Hz AC line signal... If he is plugging in a 4" speaker to test, it may not have the range to reach 60Hz, thereby he won't hear anything... You have to test it with a speaker that can generate a 60Hz signal....
 

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Discussion Starter #13
Yeah, I thought it was pretty funny (in a face-palm sort of way) that he was using such a tiny speaker - plus loud music - to test for a hum. Anyway, after I told him that my sub had an 18" Eminence driver in it, he said he thought he had an Eminence driver somewhere in the shop, and that he'd dig it out and use it to test the amp with.


If he's done so by this Friday, great; otherwise, I'll take my amp back. I figure seven weeks is enough time for a shop to determine whether or not there's a problem with a piece of equipment.


But that will leave me stuck with a humming amp - and another one at home - and worried that if I replace the Daytons with, say, an iNuke or some other amp, I'll be back in the same situation IF the electricity in my house is the cause of all this. (If that's even a possibility.)
 

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Quote:
Originally Posted by eljaycanuck  /t/1492651/fixing-a-dayton-sa1000s-hum#post_23783069


A couple of weeks ago, I picked up a used Dayton SA1000. It was extremely quiet (no humming, buzzing or any other sounds) when I got it, and for the first week it remained that way. Then it started humming quite noticeably (and the hum is amplified by the driver).


(By comparison, the other SA1000 I have is still extremely quiet.)


Having run a bunch of the usual tests on it to rule out other problems (like ground loop), I'm certain it's a problem with the amp itself. I read somewhere - regarding a different amp - that defective or worn "filter caps" may be to blame and that these usually can be replaced.


Has anyone ever replaced filter caps on an SA1000? If so:

- could you please indicate which parts you used as a replacement;

- whether a relative novice like me (with some, but not a lot, of soldering experience) could do the repair himself; and

- how well it worked out?


Thanks!

Sounds like a defective torroidal power transformer...

The laminations construction may have come loose..

Also double check the transformer mounting screws as they can vibrate if not torqued down properly..

The amplifier is assembled in China, and may just have an inexpensive, low quality transformer..


Why not check with Parts-Express for technical support..


Just my $0.05.... 👍😉
 

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Discussion Starter #16
Thanks for the input. The tech said he ruled out a mechanical vibration (which wouldn't be transmitted to the driver anyway...would it?) and he may or may not have ruled out the transformer - I'll have to ask him about it this Friday.


I did contact Dayton/PE about it, and they suggested I ship the amp to them. Unfortunately, shipping from and back to Ottawa, Canada is too much additional cost for me. (It'll be enough to pay to get the amp fixed.)
 

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I hope things work out..

Most of the less expensive audio components made in China are throw-aways..

The parts aren't available and the minimum service center bench rate fee exceeds its value..


Just my $0.05... 👍😉
 

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Does anyone have a circuit diagram for the dayton audin sa1000 amp? My sa1000 amp broke down, I replaced the fuses but they keep burning up when I start the amp.
 
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