That works for me!
https://www.diyaudio.com/forums/pass-labs/321925-diyaudio-watt-m2x-22.html#post5620442
Russellc
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Did not my link in post 1054 work?
You guys seem to be having trouble - all I do is click on actual blue post number. A new tab is created automatically. I highlight that address and copy and paste it.
This is in Chrome on my PC or on my iPhone native browser.
Actually, that’s just a piece of white paper to hide clutter on back panel so that you can focus on the mu metal box more easily.
For M2X I added Kapton tape to edges of strip that goes underneath the Edcor to prevent shorting. Top box is taped to PCB with Kapton tape.
Short story is that $20 sheet of 8in x 10in mu metal really works. Pricey stuff.
You guys seem to be having trouble - all I do is click on actual blue post number. A new tab is created automatically. I highlight that address and copy and paste it.
This is in Chrome on my PC or on my iPhone native browser.
Actually, that’s just a piece of white paper to hide clutter on back panel so that you can focus on the mu metal box more easily.
For M2X I added Kapton tape to edges of strip that goes underneath the Edcor to prevent shorting. Top box is taped to PCB with Kapton tape.
Short story is that $20 sheet of 8in x 10in mu metal really works. Pricey stuff.
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"View only 10 posts/page like I do" is pretty much the same as "Be reasonable, do it my way"
and is, laughably, unnecessary. Since it's quite simple to post links that work for everybody, no matter how many posts/page they choose to view.
Hmmm, it would be very easy to start posting links that only go to the right place for people who've set their control panel options to "50 posts/page". If anyone complains we can simply tell them, be reasonable, switch to the other way.
and is, laughably, unnecessary. Since it's quite simple to post links that work for everybody, no matter how many posts/page they choose to view.
Hmmm, it would be very easy to start posting links that only go to the right place for people who've set their control panel options to "50 posts/page". If anyone complains we can simply tell them, be reasonable, switch to the other way.
Let's use example in #1054.
This is the content of the posted link :
Note the number 311 which will open page 311 which content is dependent on control panel setting.
When a link was obtained by doing a right click on the post number in the right corner, this is the content of the link :
Note direct link to post number with no reference to any page number. Usable for everybody irrespective of control panel setting.
This is the content of the posted link :
Code:
https://www.diyaudio.com/forums/pass-labs/281520-official-m2-schematic-311.html#post5569239When a link was obtained by doing a right click on the post number in the right corner, this is the content of the link :
Code:
https://www.diyaudio.com/forums/pass-labs/281520-official-m2-schematic-post5569239.htmlThanks for explaining that. I never even knew there were all these links that I have posted in last 6 years and 25k posts that don't actually work for some members. Sorry...
So, I could just reformat the simple link that I normally use by:
moving the postxxxx.html to where the page number is and get rid of the page number? Or go through the Vulcan mind melt super secret handshake that Mark posted to do this? (heck, I don't even know how to set my view to 50 per page - indeed it is a dark art. Reading 50 per page is like looking through a old style line (circa 1980's) dot matrix printer paper that never ends...
)Official M2 schematic
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Okay, I get the "teach a man to fish" mantra.
Have you considered the "I will be less condescending" one?
"View only 10 posts/page like I do" is a viable option, is it not?
The Melbourne
DHL shipment just arrived. I'll be reasonable and do it your way, either SMT or TH...
I will try to verify that it works tonight.
Lets' start with data for TH version
Schematic for v1:
Stuffing guide:
Parts list below in attachments.
DHL shipment just arrived. I'll be reasonable and do it your way, either SMT or TH...
I will try to verify that it works tonight.
Lets' start with data for TH version
Schematic for v1:
Stuffing guide:
Parts list below in attachments.
Attachments
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Vias in the annular rings surrounding M3 bolt holes are a good idea! Ultra cautious reliability-obsessed people like joshua43214, who might skeptically question the long term viability of the top side annulus AND the bottom side annulus AND the plated-thru-hole of the M3 diameter bolt, now have to imagine a scenario in which eight top-copper-to-bottom-copper vias, all go open circuit simultaneously. For some reason.
Of course, it . could . happen .
And it also could happen that Charlize Theron and Halle Berry could ring my doorbell tonight and ask if I wanted to buy Girl Scout Cookies while modeling Victorias Secret underclothes. It . Could . Happen .
Of course, it . could . happen .
And it also could happen that Charlize Theron and Halle Berry could ring my doorbell tonight and ask if I wanted to buy Girl Scout Cookies while modeling Victorias Secret underclothes. It . Could . Happen .
Happened to me, just last week. I told them as much as I appreciated the offer, I have a Girl Scout in the house already and she doesn't make me model Victorias Secret underclothes while I buy the cookies.
Pretty sure it was Halle Berry and Charlize Theron, though, not the other way around. Does that still count?
^^This
I sleep better at night now
My point was about the washers, post profile, and post material.
There are many reasons why conventional star washers are not a good idea, most of them relate to contact surface area, and damage to the pads. Placing any washer between the post and pad, just adds extra opportunity for resistance between the pad a post. Adding a conventional star washer between the nut and pad reduces contact area and will distort the pad, which very likely will result in cutting through the gold leafing with repeated use.
The washer I linked will not damage the pad, and has greater contact area.
using hex posts without a washer will put a hex imprint on the board, which could decrease contact after removal/installation, thus a round post or a hex post with a round profile at the end is preferred.
Most coating for aluminum conduct very poorly. The particular coating (iridite) on the posts in the BOM is supposed to be conductive. However, a quick Google search will tell you that only certain classes of iridite coating actually conduct well. The data sheet from Keystone only calls it "Clear Iridite," whatever that is. The only reliable source I know for gold plated standoffs is Allo.com, but they charge a ton for shipping. Plenty of gold colored posts on Ebay though.
So to sum up: Large contact area is good, low contact area is not good. fewer mechanical parts in the signal path is good, more mechanical parts in the signal path or not good. Not damaging the pad is good, damaging the pad is not good. Conductive coatings are good, non-conductive coatings are not good (no coating on aluminum is bad).
So, I would not call it being overly cautious. Just plain old due diligence combined with a lifetime of experience with fasteners.
Most grateful for teeing that one up. The ladies were good sports about it, BTW, and agreed to model the undies themselves, if I would buy some cookies from them. Seemed fair enough.
I think they were cookies.
The TH Melbourne has been tested and initial few test tracks sound great. There is also an incredible smoothness that comes from a single ended Class A front end. Will do some longer term listening and report later on sound quality. This was build a bit off spec as I used what was in my bench. Only had 220uF caps for the CRCRC, and 10uF vs 47uF for the smoothing caps on the internal nodes. Also, just cheap resistors and caps in general except the input coupling cap is Silmic II. I did not have the proper 0.1% tolerance resistors needed to set the DC offset at zero - it ended up at 90mV so I ended up using a home made non-polar electrolytic with a pair of back-to-back 100uF caps. Maybe a pot would not be a bad idea here... Also, the bias current on the front end is running quite a bit higher than the predicted model, so not sure what's going on but perhaps a resistor value may be off. It is running 45mA when should be around 16mA. So about 3x more heat than usual but still manageable with local heatsinks (although they are hot).
However, I found a major error on this PCB that managed to slip by due to my carelessness - pins 1 and 3 are flipped, despite studying this and knowing what they were supposed to be... So I had to use flying leads to the proper bolt pad for testing. Will correct on final GB board.
However, I found a major error on this PCB that managed to slip by due to my carelessness - pins 1 and 3 are flipped, despite studying this and knowing what they were supposed to be... So I had to use flying leads to the proper bolt pad for testing. Will correct on final GB board.
Attachments
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