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Buckeye Hypex Nc502mp Multichannel Amp Teardown

If I was in the market, I would consider your products despite your solderphobia, because it seems your decisions are rational-based between solder/crimp divide.
I would even buy one, if I can convince @sarumbear to lend me a few k.;)
 
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Is he "manufacturing" or assembling?
Technically he is assembling but legally, like from the point of view of customs duty, the amplifier that he sells is his merchandise, hence he is the manufacturer. It all depends your point of view. I used the legal view.
 
Regarding crimp strength for the connections meant for quick disconnects: I can tell you that when I first tested my crimps, I used needle nose pliers to hold the quick disconnect and another pair to pull on the wire below the crimp point...the wire bundle started pulling through the wire sheath and began to rip before the crimp ever lost hold. So for this application, I can assure everyone the wire will never come loose from my quick disconnects.

On top of that, I use adhesive heat shrink on all the power quick disconnects for safety (if one ever slips off there won't be metal-on-metal contact).
 
Why even bother using FastOns when the posts clearly show a stamped/punched hole for soldering?
It's not "for soldering" -- the hole in the male FastOn is designed to accommodate a small raised circular area on the mating surface of its female counterpart. This feature supposedly helps prevent a FastOn connection from becoming "FastOff," especially when it's vertically oriented. :cool:
Female_Crimp_Connectors370[1].jpg
 
Some follow-up if you consider flipping the amplifier upside down...

Before I sent his @Buckeye Amps amp back to @AdamG247, I mentioned that the input and the control signals go to IDC connectors are friction fit. Since I knew Adam would be using the amp upside down, I added some butyl rubber around theses connectors. These are the connectors I highlighted here…

80FFA552-35E8-44E9-9997-03C4041DF01D.jpeg


Despite my extra effort, when Adam got the amp, one of the connectors had become partially unseated. So, while it may have just been knocked loose in shipping, given that it is working against gravity, Adam plans to add some Tesa tape to secure the connectors further.

While one could argue the use Hypex’s choice of a connector without retention is questionable, given the known shortcoming, it falls on the builder to remediate.
 
How many amps has @Buckeye Amps sold, and of those, how many have arrived with loose connectors? I am not a huge fan of them, but rarely have I seen them fail on a new (or even old) product unless subjected to many pull/attach cycles. The cheap ones of soft metal, sure, but decent ones IME last a long time.
 
Full disclosure. The amp build Rick is taking about made 3 separate ups trips. From origin at Buckeye to Amir in Wash St, then back to Rick and finally to me in SW Florida. It very well may have been dropped, kicked and tossed a few extra times as it crisscrossed the entire country.
 
How many amps has @Buckeye Amps sold, and of those, how many have arrived with loose connectors? I am not a huge fan of them, but rarely have I seen them fail on a new (or even old) product unless subjected to many pull/attach cycles. The cheap ones of soft metal, sure, but decent ones IME last a long time.

Thanks Don!

I agree when the connectors are used with ribbon cable…

I suspect part of the problem is less contact points and more strain from the much heavier Mogami wiring. The added strain relief may be an abundance of caution. I do it and so do others. @Buckeye Amps can make his own call. Am just providing some additional insight particularly for those who might be turning their amp upside down.
 
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So the J4 and J6 connectors have no latching and instead rely on the actual pins in the female connector to hold everything in place (each pin applies light clamping force to its mating connector).

That being said, I have toyed with the idea of a simple spot of hot glue or some other adhesive but to date I have refrained, mainly due to making it easy for the user to disconnect and reconnect if they ever want to upgrade a module.

From the top of my head, maybe 1 in 50 orders has had an issue with a connector coming loose during shipping. But never has one come loose during normal usage/setup/lugging around a persons house AFAIK.
 
How many amps has @Buckeye Amps sold, and of those, how many have arrived with loose connectors? I am not a huge fan of them, but rarely have I seen them fail on a new (or even old) product unless subjected to many pull/attach cycles. The cheap ones of soft metal, sure, but decent ones IME last a long time.

The only failure of a good-quality FastOn connection I've ever encountered was to the tweeter of an old JBL bookshelf speaker that had clearly been stored in a very damp environment -- it was caused by corrosion, not loss of contract tension.
 
So the J4 and J6 connectors have no latching and instead rely on the actual pins in the female connector to hold everything in place (each pin applies light clamping force to its mating connector).

That being said, I have toyed with the idea of a simple spot of hot glue or some other adhesive but to date I have refrained, mainly due to making it easy for the user to disconnect and reconnect if they ever want to upgrade a module.

From the top of my head, maybe 1 in 50 orders has had an issue with a connector coming loose during shipping. But never has one come loose during normal usage/setup/lugging around a persons house AFAIK.
My personal opinion is that it is OK as is, but if you were to add some type of user-removable glue or tape, that would be a plus. However, I'd avoid using any glue that was not easily removable for the reason you stated.
 
Looking at @Rick Sykora 's picture, I'd be inclined to change the routing to the connectors just a hair by letting the cables be just a little bit longer to allow more strain relief, and would probably skip the tie-wrap. It provides a cleaner look but potentially more strain (and higher crosstalk) on the cables. Having a straight shot to the connectors makes shorter cable, and again a clean look, but could "pull" a little on the connectors. Making the cables a little longer and moving them "down" to the bottom edge of the board in the picture, they would not run over the top of the inductors (noise coupling), and could have a little more strain relief to the connectors. May do nothing, just thinking out loud.
 
Looking at @Rick Sykora 's picture, I'd be inclined to change the routing to the connectors just a hair by letting the cables be just a little bit longer to allow more strain relief, and would probably skip the tie-wrap. It provides a cleaner look but potentially more strain (and higher crosstalk) on the cables. Having a straight shot to the connectors makes shorter cable, and again a clean look, but could "pull" a little on the connectors. Making the cables a little longer and moving them "down" to the bottom edge of the board in the picture, they would not run over the top of the inductors (noise coupling), and could have a little more strain relief to the connectors. May do nothing, just thinking out loud.
This :)

I have been doing this just recently on current builds (and usually I tried to do it, subconsciously, on past builds because of the strain relief you mentioned).
 
This :)

I have been doing this just recently on current builds (and usually I tried to do it, subconsciously, on past builds because of the strain relief you mentioned).

Btw, while I agree with @DonH56 's suggestions, I did cut the tie wraps on one amp module to test whether I could get lower noise than the original wiring. I did not. While getting further from the inductors is good advice, the picture is misleading as it does not show how far away they are vertically.

As for the crimps, I did check all the speaker ones before I shipped back to @AdamG247 and they were fine. :cool:
 
Btw, while I agree with @DonH56 's suggestions, I did cut the tie wraps on one amp module to test whether I could get lower noise than the original wiring. I did not. While getting further from the inductors is good advice, the picture is misleading as it does not show how far away they are vertically.

As for the crimps, I did check all the speaker ones before I shipped back to @AdamG247 and they were fine. :cool:
Rick, what noise bandwidth did you measure? I was thinking it might help better reject noise at the switching frequency, which should be inaudible...

No dog in this hunt, just curious, thanks - Don

Edit: I do own a Buckeye 2xNC252 amp so maybe a small dog... ;)
 
Rick, what noise bandwidth did you measure? I was thinking it might help better reject noise at the switching frequency, which should be inaudible...

No dog in this hunt, just curious, thanks - Don

Edit: I do own a Buckeye 2xNC252 amp so maybe a small dog... ;)

Sorry, not that high. I am usually just looking at the audible spectrum. Notably, Amir had found some 60 Hz noise in one channel. I was able to reproduce, but removing the tie wrap and moving the signal wires around did not yield any improvement.
 
Sorry, not that high. I am usually just looking at the audible spectrum. Notably, Amir had found some 60 Hz noise in one channel. I was able to reproduce, but removing the tie wrap and moving the signal wires around did not yield any improvement.

Yah, I suspect the 60 Hz coupling is elsewhere. Thanks for poking around!
 
I used to use a washer underneath the lug, but after the first tear down back in 2020 it was suggested to have the lug directly contacting the bare case metal as a washer can affect grounding performance (I think Amir pointed to an article at the time discussing this). I will look back through that tear down thread.
When I was running corrective action at a major computer firm, one of my victories was to BAN all star washers from the plant. So many failure modes it was not funny. We eventually got rid of most split-locks using proper torque instead. Deformed thread hardware was far more reliable.

For good reliability contact, you need to make it "gas tight" which is easy with no washer.
 
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