Trying to better understand
Dario gave good reasons for only using LM3886TF and I respect that, but I want to think about another option. I'm hoping KSTR may have some opinions or experience that would help me understand.
We have learned through KSTR and Suburra that controlling the potential of the heatsink is important to controlling noise. Using the 'TF' and grounding the heatsink is our solution and it looks like a good one.
What I am wondering is what would happen if you did use the uninsolated 'T' chip and left the heatsink at V-? My first guess is that the heatsink might act as an antenna broadcasting the ripple on the V- rail. In that case, why would anyone ever use the 'T' chip in a high quality application?
I suppose that the opposite could happen. The fact that the heatsink would be connected to a "constant" and non-zero potential might control the hum, but I think this is much less likely. Any thoughts?
This is purely a theoretical question as I plan on using 'TF' chips.
Dario gave good reasons for only using LM3886TF and I respect that, but I want to think about another option. I'm hoping KSTR may have some opinions or experience that would help me understand.
We have learned through KSTR and Suburra that controlling the potential of the heatsink is important to controlling noise. Using the 'TF' and grounding the heatsink is our solution and it looks like a good one.
What I am wondering is what would happen if you did use the uninsolated 'T' chip and left the heatsink at V-? My first guess is that the heatsink might act as an antenna broadcasting the ripple on the V- rail. In that case, why would anyone ever use the 'T' chip in a high quality application?
I suppose that the opposite could happen. The fact that the heatsink would be connected to a "constant" and non-zero potential might control the hum, but I think this is much less likely. Any thoughts?
This is purely a theoretical question as I plan on using 'TF' chips.
I don't have the answer but, usually, people used T chips with insulating pads.
Russian K71-4 Polystryene Caps
Sorry for so many posts in a row, but each are a different subject, so....
It looks like guys from this thread are buying these up. I just ordered a few for me and they appear to be going fast. If you think you might like to try these, I recommend that you hurry, they may already be gone. Also, if you miss out on the first link, he had some others in lots of 4 listed elsewhere in his store.
As for me, I plan on comparing the K71-4, Sonicap Gen 1, and possibly some Mundorf ZNs. I like Bob's suggestion of passing around a pair of True Coppers, but I am planning on tri-amping my next speaker project, so 6 True Coppers gets pricey.
Sorry for so many posts in a row, but each are a different subject, so....
It looks like guys from this thread are buying these up. I just ordered a few for me and they appear to be going fast. If you think you might like to try these, I recommend that you hurry, they may already be gone. Also, if you miss out on the first link, he had some others in lots of 4 listed elsewhere in his store.
As for me, I plan on comparing the K71-4, Sonicap Gen 1, and possibly some Mundorf ZNs. I like Bob's suggestion of passing around a pair of True Coppers, but I am planning on tri-amping my next speaker project, so 6 True Coppers gets pricey.
Sure. I Forgot it...
I'm planning to put some text about it on PCB... it shouldn't be used if the heatsink is part of chassis (and thus probably connected to safety ground).
The most recent layout:
It's also larger (0.5 cm) than beta boards.
Attachments
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I'm often using the non-isolated T-version on an otherwise floating heatsink without isolating pad (Mica, Kapton or Al2O3) for test builds without problem. You must take care of NEVER shorting the heatsink to GND or anything else --> instant smoke. Even when explicitly connecting the HS to V- it is not any safer (and shorting the supply in case of error), as the metal tab must never be used to carry current.
A non-grounded / non-earthed heatsink is not practicable for a final product. The isolated version of the chip was made to speed up and simplify mass production of amplifiers.
-------:-------
Due to (temporary) health problems I wasn't able to work on the test build today, maybe tomorrow, we'll see. Since the basic question about C14 was answered I would have no problem if Dario now decides to go ahead as planned with PCB manufacture. The PCB is pretty OK as is.
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If that's really, really you, it's fortunate you chose audio instead of video as your major hobby interest.
And that's not Dario's face. He is actually a 84 year old man with white hair and a big bushy mustache.
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Same goes for me, this portrait is how I feel (a hero of my subculture)... Nasty shock when I look in a mirror, or hear what my wife thinks of me!
I also stopped chain-smoking (again) three years ago....!
I was wondering if anyone is up for sharing a mouser BOM for this order?
I see mouser have a method for entering a BOM, saving it, and then 'sharing' it with people (obviously in their interest, but helpful in a way).
I got a little way into it but it's tedious work. I would be happy to share the load and enter say 1/4 of the order if others would chip in also.
I think we could enter separate BOM's for different sections of Dario's BOM, add them to our carts one by one and then check out when everything is there. It's quicker to delete a few items some folk don't need than for everyone to enter all the parts one by one.
Any ideas? If someone has already placed an order we might be able to use that?
I'm not working for mouser by the way, they ship to Japan from Hong Kong, which is quicker for me than shipping from North America or Europe, and they have good stock levels usually.
Bill
I also stopped chain-smoking (again) three years ago....!
I was wondering if anyone is up for sharing a mouser BOM for this order?
I see mouser have a method for entering a BOM, saving it, and then 'sharing' it with people (obviously in their interest, but helpful in a way).
I got a little way into it but it's tedious work. I would be happy to share the load and enter say 1/4 of the order if others would chip in also.
I think we could enter separate BOM's for different sections of Dario's BOM, add them to our carts one by one and then check out when everything is there. It's quicker to delete a few items some folk don't need than for everyone to enter all the parts one by one.
Any ideas? If someone has already placed an order we might be able to use that?
I'm not working for mouser by the way, they ship to Japan from Hong Kong, which is quicker for me than shipping from North America or Europe, and they have good stock levels usually.
Bill
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Thanks for the good wishes, but the runs are still nailing me down at home... I might at least be able to play a little with the layout in EAGLE (out of competition, that is).
- Klaus
It only has to be done once and can be shared. Please see this link.BOM Tool Help: Mouser.com
I use the Excel method with the downloadable template.
I'm sure Dario will/can set things up so builders can just use his after they establish a Mouser account.
If someone already has or doesn't want certain parts, there is an opportunity to edit the list before final purchase.
I use the Excel method with the downloadable template.
I'm sure Dario will/can set things up so builders can just use his after they establish a Mouser account.
If someone already has or doesn't want certain parts, there is an opportunity to edit the list before final purchase.
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Hi Bill,
the BOM can be easily imported using the Mouser import tool.
I've added a column on the BOM spreadsheet with the Import tool codes, simply copy it to clipboard and paste in the Import tool, click the import button and you're done (remember that the BOM is for one monoblock).
Dario
That's great Dario, very helpful! I hate wasting time doing stuff that isn't fun!
Especially duplicating tedious work!
Much appreciated!
Bill
Just a couple more options/clarifications provided by Mouser.
Sharing a Project with your Colleague(s)
Click on the “Project Manager” link.
Click on the link called “Share Project”, and then simply follow the instructions from there.
If you share a Project with your colleagues you will have the option to either send them read only copy that they will be able to view and order from our website, or you can send them an editable copy so that you can work together on updating and creating the project.
If you send your colleague an editable copy you will be able to see all of their changes from you Project Manager and you will have the ability to accept or deny any changes that they have made.
If you would like to share your project with a group there is a URL is created and you can post that URL or send to anyone that you would like. This works for both editable projects and read only projects.
Sending a Copy of Your Shopping Cart to a Colleague
In the Cart click on the link to "Share this Cart with a Colleague". Then follow the instructions listed. An e-mail will be sent to your colleague so that they can access a copy of your shopping cart and place the order for you. They will be able to access the shopping cart by clicking on a link in the e-mail that is sent to them or they can enter the access ID number on our EZ Buy page on our website.
Sharing a Project with your Colleague(s)
Click on the “Project Manager” link.
Click on the link called “Share Project”, and then simply follow the instructions from there.
If you share a Project with your colleagues you will have the option to either send them read only copy that they will be able to view and order from our website, or you can send them an editable copy so that you can work together on updating and creating the project.
If you send your colleague an editable copy you will be able to see all of their changes from you Project Manager and you will have the ability to accept or deny any changes that they have made.
If you would like to share your project with a group there is a URL is created and you can post that URL or send to anyone that you would like. This works for both editable projects and read only projects.
In the Cart click on the link to "Share this Cart with a Colleague". Then follow the instructions listed. An e-mail will be sent to your colleague so that they can access a copy of your shopping cart and place the order for you. They will be able to access the shopping cart by clicking on a link in the e-mail that is sent to them or they can enter the access ID number on our EZ Buy page on our website.
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Off Topic
Bob,
If Dario is really, really an 84 year old man with white hair and a bushy mustache, then I am really impressed. I hope that, when I am 84, I am still working, still staying up all night working on audio projects, still able to hear the difference in sound in the orientation of a capacitor, and still able to go out on the town and dance salsa
On second thought, I take some of that back. I already enjoy a good nap too much to stay up all night.
Jac
Bob,
If Dario is really, really an 84 year old man with white hair and a bushy mustache, then I am really impressed. I hope that, when I am 84, I am still working, still staying up all night working on audio projects, still able to hear the difference in sound in the orientation of a capacitor, and still able to go out on the town and dance salsa
On second thought, I take some of that back. I already enjoy a good nap too much to stay up all night.
Jac
If Dario is really, really an 84 year old man with white hair and a bushy mustache, then I am really impressed. I hope that, when I am 84, I am still working, still staying up all night working on audio projects, still able to hear the difference in sound in the orientation of a capacitor, and still able to go out on the town and dance salsa
Jac, thanks!
I've missed that one!
But I must correct Bob, It's actually me in the photo when I was young (about 35)... you know, in the sixties color pictures were a quite a new technology and I wanted to try...
So, while I'm really 84 with bushy mustache, that picture represent my inner self-image.
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