Interesting, X.
After putting liquid white-out at 3 places:
* the top of the bracket that the CPU cooler is bolted to
* the top edge of the (horizontal) CPU cooler's aluminium base plate
* the end of the heat pipe at the other end of the fin stack
... I still get lower readings than you do??
There's a few degrees between readings on one channel and the other but basically, I get:
* without the Noctua 'noise reduction' cables:
- bracket L: 37 deg C R: 30 deg C
- heat pipe L: 41 deg C R: 38 deg C
- P mosfet L: 33 deg C R: 33 deg C.
* using the 'noise reduction' cables - which reduce the fan speed:
- bracket L: 37 deg C R: 33 deg C
- CPU cooler's base L: 39 deg C R: 39 deg C
- heat pipe L: 39 deg C R: 39 deg C
- P mosfet L: 30 deg C R: 31 deg C.
Ambient temp was 20 deg C.
There is a bit of fan noise, though.
Andy
Well if your IR thermometer is accurate (does it measure your forehead circa 36C?) then your amp is running fairly cool as your heatsinks and fan are doing a great job. I think this is normal as I was talking about my Dell CPU heatsinks dissipating 150w whereas you are closer to 90w. My passive heatsink is 55C so an active one with fan at 38C sounds about right.
Don’t worry about it anymore. It’s running cool as a cucumber.
Don’t worry about it anymore. It’s running cool as a cucumber.
Good test, X - I just measured my forehead (several times!) ... and the reading was 33.7 deg C.
So it would seem my temp gun measures 2 or 3 deg low.
Still, 2 or 3 deg higher than what I posted ... is still good.
Andy
X, Hugh,
Now for those about to rock it with the AN in full glory choosing back in black:
BRZHIFI BZ4015 double radiator aluminum case for power amplifier|Amplifier| - AliExpress
BRZHIFI BZ4315A double radiator aluminum case for power amplifier|Amplifier| - AliExpress (More depth, but looks like speaker and RCA connector holes need to be drilled for this one)
p.s Did you guys get the double AC/DC pun?
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Andy, what is the current flowing through source resistors (0.12 Ohm) ?
Are they warm/hot?
Are they warm/hot?
Good test, X - I just measured my forehead (several times!) ... and the reading was 33.7 deg C.
So it would seem my temp gun measures 2 or 3 deg low.
Still, 2 or 3 deg higher than what I posted ... is still good.
Andy
The current through R142 (0.12 ohm, as you say, for the 4R version) is:
* channel 1: 373mV - so 3.11a
* channel 2: 363mV - so 3.03a
And yes, minek, they are hot to touch - I'd say about 40 deg C.
Andy
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Good work Andy, have you had a chance to sit down and have a good listen to the AN?
Hugh might be around knocking on your door for a listen as well
Not yet, Gary. I had been waiting for my Vampire spkr BPs to arrive from the USofA (they are 10 days late!
) ... but Hugh has suggested I just rig up a temporary connection. This happens to be not so difficult! I happen to have some of the spkr wire I make, lying around - and all I need to do is crimp a spade connector onto one end ... which can fit over the spade lug on my SSRs, with bare wire at the spkr end.
(I had made it up to send it someone, to compare against his spkr wires - but he has not yet got around to making his up.
)So I should be able to have a listen this arvo - and compare the AN 4R against the NAKSA 80s I'm currently using to power my mid panels and ribbons.
First on the mids (3.2 ohms) - then on the ribbons (2 ohms).
Andy
Haha - no positive achievement yet, Hugh,
Monday arvo:
* I connected the input RCA to each AN board - but dispensing with the 2-pin header and just using the (heatshrinked) crimp connectors.
* then I found I had to make up a pair of spkr cables from scratch, as the ones I had lying around - which I thought I could make use of - turned out not to be suitable. And, as well as spade connectors on the AN-board end, I had to solder banana plugs on the other end ... as I couldn't use bare wire, coz my Maggie panels have banana sockets, not binding posts.
* then I screwed the back panel onto the case - and this revealed a problem! The bolt holes for the vertically-mounted AN boards are located centrally between the top and bottom edges of the back panel - and, in this position, the AN boards interfere with the SSR boards which I mounted on the bottom panel.
Tuesday, I took a day off from the project and did other things.
So I now have to:
* undo all 8 AN-board bolts.
* unplug all 10 connections on each AN board.
* remove the RCA sockets and the earth terminals underneath them, to allow me to put the ends of each back panel on my drill-press.
* mark and drill 8 holes 1/2" above the existing holes, to raise the position of the AN boards on the back pael. This of course will ruin the look of the rear panel!
* then re-attach all the connections to the AN boards.
* and bolt them into their new positions.
Then, I should be able to screw on the back panel without pressing against the SSR boards ... and conduct my listening test.
It's nearly noon, here - but I'm hoping I'll be listening late this arvo.
Andy
Monday arvo:
* I connected the input RCA to each AN board - but dispensing with the 2-pin header and just using the (heatshrinked) crimp connectors.
* then I found I had to make up a pair of spkr cables from scratch, as the ones I had lying around - which I thought I could make use of - turned out not to be suitable. And, as well as spade connectors on the AN-board end, I had to solder banana plugs on the other end ... as I couldn't use bare wire, coz my Maggie panels have banana sockets, not binding posts.
* then I screwed the back panel onto the case - and this revealed a problem!
The bolt holes for the vertically-mounted AN boards are located centrally between the top and bottom edges of the back panel - and, in this position, the AN boards interfere with the SSR boards which I mounted on the bottom panel.Tuesday, I took a day off from the project and did other things.
So I now have to:
* undo all 8 AN-board bolts.
* unplug all 10 connections on each AN board.
* remove the RCA sockets and the earth terminals underneath them, to allow me to put the ends of each back panel on my drill-press.
* mark and drill 8 holes 1/2" above the existing holes, to raise the position of the AN boards on the back pael. This of course will ruin the look of the rear panel!
* then re-attach all the connections to the AN boards.
* and bolt them into their new positions.
Then, I should be able to screw on the back panel without pressing against the SSR boards ... and conduct my listening test.
It's nearly noon, here - but I'm hoping I'll be listening late this arvo.
Andy
If you go back to the pic I provided in post #1213, you can see how the SSRs are mounted on the floor of the case, just forward of the AN boards. It wasn't apparent when the back panel was resting 45 deg outwards ... but when I fix it in the vertical position ... the spades which are located at the bottom of each AN board collide with the SSR board.
So raising the AN boards will stop this from happening.
Andy
Hi Andy,
I feel for ya man, taking one step forward only to be knocked back two steps can be frustrating.
I was taking a closer look at the picture from post#1213, it’s a bit blurry, but it looks like the metal crimp sockets are sticking out the back of all the Molex KK 2-pin female housing?
I feel for ya man, taking one step forward only to be knocked back two steps can be frustrating.
I was taking a closer look at the picture from post#1213, it’s a bit blurry, but it looks like the metal crimp sockets are sticking out the back of all the Molex KK 2-pin female housing?
Hi Andy,
I see your photo now. It would seem that you should move your SSR boards as they are in the floor where the screw holes don’t matter. Whereas redrilling the amp boards cause unsightly holes on the rear panel. You could even mount the SSRs to the air vent slots that are there. I think an M3 fits through those slots. Or even sheet metal screw if you had to.
I am concerned about your Molex KK connectors. It looks like the crimp connectors are not fully seated into the shell. If not fully seated, the will not engage the PCB mounted male pins. But then you mention soldering them directly. The whole point of having them is to allow quick and easy removal of all the connectors on the board. Do you not have a proper crimping tool? They are $20 and in a pinch, use needle nose pliers. But I highly recommend getting real crimp pliers. They make your connections secure and professional. Soldering wires directly to a board is not recommended. It is susceptible to strain and fatigue and will break/fail much sinner than of having a connector not relieve the stress.
If you need help with crimpers pliers I am sure someone nearby in Oz can tell you where to get them locally. I got mine from Amazon. A popular one are the “Engineer” brand.
X and I came to the same conclusion and that is to move the SSRs. That might be easier. If however you choose to go with the back panel, you can use something like this: Prime-Line, Black Products KD 16082 Self Adhesive Textured Plastic Screw Hole Covers (Pack of 53) - - Amazon.com
to cover the holes... I use them to cover the holes on handle screws and such. Peel stick and done.
to cover the holes... I use them to cover the holes on handle screws and such. Peel stick and done.
Yes, they do stick out a bit, on those 2-pin headers, V. I did check the underside of each header, to make sure the connector was right at the bottom end of the header, before plugging them in. And since the LEDs and the SSR turned 'On' ... the pins must've been making contact.
Absolutely true about the unsightly holes, X.
But the SSRs are currently sited midway between the input RCAs and the mains wires ... and I would prefer not to move them sideways towards either one of these.No - not soldering them directly ... simply not using the plastic header and plugging each crimped socket directly onto its pin. If you use heatshrink over the crimped socket ... it helps to keep the socket tight.
I bought a crimper from Amazon, X, soon after you posted a list of the ones you use.
Now I've drilled the new holes, JT ... the old holes (only M3!) don't look that bad. I think your adhesive covers would look far worse!
Yes, Hugh too tight, really!
But as I said earlier, to me ... moving the SSRs is problematical.
Anyhoo, I have drilled the new holes and fitted the AN boards back on the rear panel. But it's taken more time than I had anticipated - as I also had to fix the problem of the base panel of the case drooping down below the bottom edge of the rear panel (even though there's not much weight on the base, at the back of the case).
I had some 3/4" x 1/8" aluminium angle lying around - so I cut a couple of lengths and tapped the holes that I drilled in these brackets. So one bracket is now bolted to the base of the case - with a hole drilled into the back panel, to take another bolt.
Tomorrow, I will replace the one earth bolt that you can see in the pic a few posts back with 2 earth bolts (2" apart) ... as there are too many earth connections, really, for the one bolt.
Then, I can listen!
Andy
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