I've had feedback from a friend that buyed one of my spare kits from the previous GB and he's a person that I trust.
He first used all PRPs like we're going to do and than experimented with resistors and caps too:
R13 best Caddocks MK132 and second best carbon films
R11 best Kiwames and second best carbon films (this is a very critical resistor for SQ)
R10 best Takmans Carbon and second best carbon films
R3 best Mills, second best Caddocks
R12 still under investigation but both nude Vishays and Takmans carbon were better, MK132 no good here
C9 Silmics sounds good but BG STD were way better, FK even better than STD (better no bypass with the FK)
C4, C7 Best Evox Rifa SMR (PPS)
C5 best Wima MKP10
Interesting, isn't it?
He first used all PRPs like we're going to do and than experimented with resistors and caps too:
R13 best Caddocks MK132 and second best carbon films
R11 best Kiwames and second best carbon films (this is a very critical resistor for SQ)
R10 best Takmans Carbon and second best carbon films
R3 best Mills, second best Caddocks
R12 still under investigation but both nude Vishays and Takmans carbon were better, MK132 no good here
C9 Silmics sounds good but BG STD were way better, FK even better than STD (better no bypass with the FK)
C4, C7 Best Evox Rifa SMR (PPS)
C5 best Wima MKP10
Interesting, isn't it?
Updated BOM for extra boards
I've decided to update the BOM for extra boards according to the feedback I've received.
So R13 now is a Caddock MK132V, carbon film as alternative.
All others shunt resistors are now carbon film only, no MF alternatives.
R11 is now part of the 'for audio' category.
I'm waiting for feedback about C12, it could became a Wima FKP2.
Oops Regi... I think you'll have to update again your reference archive...
I've decided to update the BOM for extra boards according to the feedback I've received.
So R13 now is a Caddock MK132V, carbon film as alternative.
All others shunt resistors are now carbon film only, no MF alternatives.
R11 is now part of the 'for audio' category.
I'm waiting for feedback about C12, it could became a Wima FKP2.
Oops Regi... I think you'll have to update again your reference archive...
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I got the KlickNship notice today. I guess something is about to happen!
Can't wait to have some nice bass at my place -LOL!
I guess its time to dig out the old Hafler amp carcass and get her ready for a new set of primo parts! Found her in a junk pile on the curb, one day when I was out running.
You get to do the next Ultimate GB Dario!
Been a labeling and boxing fool for last few days.
About 40 boxes will ship tomorrow. Several of you probably got emails already since a lot of the postage I was able to print from Paypal. Not sure yet if I can do international postage from paypal. I know I can but it wants me to fill out that big white international slip and I prefer the small green ones. Will ask the post office when I am there tomorrow.
Uriah
Been a labeling and boxing fool for last few days.
About 40 boxes will ship tomorrow. Several of you probably got emails already since a lot of the postage I was able to print from Paypal. Not sure yet if I can do international postage from paypal. I know I can but it wants me to fill out that big white international slip and I prefer the small green ones. Will ask the post office when I am there tomorrow.
Uriah
Oh I have one of those Halfer cases to! Rock solid and great for any amp that can fit in it!
Would any of you want to buy these chassis? They are 7x12x3.5" Aluminum front plate and steel chassis. Cant remember if the back is steel or aluminum. Lots of room in there and we would actually have a nice chassis. Monoblock, but thats kinda nice to. I have seen them and they do look good. Nice black anodized on the front. Kind of utilitarian but I still like them. Anyway, the guy lives down the street from me and said next time he buys them I could get in on the purchase.
I can get them without the silkscreen of course.
Front panel is THICK and they look nicer than his mockup.
You can see the back panel on this page http://www.d-sonic.net/
Uriah
An externally hosted image should be here but it was not working when we last tested it.
Would any of you want to buy these chassis? They are 7x12x3.5" Aluminum front plate and steel chassis. Cant remember if the back is steel or aluminum. Lots of room in there and we would actually have a nice chassis. Monoblock, but thats kinda nice to. I have seen them and they do look good. Nice black anodized on the front. Kind of utilitarian but I still like them. Anyway, the guy lives down the street from me and said next time he buys them I could get in on the purchase.
I can get them without the silkscreen of course.
Front panel is THICK and they look nicer than his mockup.
You can see the back panel on this page http://www.d-sonic.net/
Uriah
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I am staying out of the grounding discussion. Ground it for every possible mode of failure or even swallowing it if that makes you feel safer. Perhaps enclose it in concrete so if a falling tree crushes your house the amp will still be okay and won't jump up and shock you. And what parent would ever let their baby suck on an RCA plug? If that wasn't just a silly joke, then perhaps that kid should be electrocuted so your genes are not passed on.
Dario, thanks for those updates on additional listening tests. I am thrilled BG's carried the day at C9. Interesting that no bypass is needed with FK. That could be very nice!
I don't understand what effect R11 could have on the signal. I thought all it did was isolate signal ground from power ground (there's that word again!). That's the last place I would expect a change, but I'm no designer, and I'm sure not an expert about that part--I never tried anything else there.
The problem with using a large, high-quality resistor such as Mills at R3 is fitting it on the board. The lead spacing of the Caddock MP930 is perfect, although the heatsink for it needs to be modified and squeezed in. A big resistor needs to be stood on end with one very long lead to the board.
Did your friend try Shinkoh's anywhere? I know they're not readily available, so maybe he couldn't get them. Takman are much cheaper, and I wish I had known they sound best before I bought the Shinkoh's! I would stay away from carbon resistors, though. I have heard too many bad things about them, although they are supposed to sound great in some circuits. Carbon film might be okay, though.
I can see how changing C12 might make an improvement.
What about your experiment with power filtering to avoid motor starting pops?
Peace,
Tom E
Dario, thanks for those updates on additional listening tests. I am thrilled BG's carried the day at C9. Interesting that no bypass is needed with FK. That could be very nice!
I don't understand what effect R11 could have on the signal. I thought all it did was isolate signal ground from power ground (there's that word again!). That's the last place I would expect a change, but I'm no designer, and I'm sure not an expert about that part--I never tried anything else there.
The problem with using a large, high-quality resistor such as Mills at R3 is fitting it on the board. The lead spacing of the Caddock MP930 is perfect, although the heatsink for it needs to be modified and squeezed in. A big resistor needs to be stood on end with one very long lead to the board.
Did your friend try Shinkoh's anywhere? I know they're not readily available, so maybe he couldn't get them. Takman are much cheaper, and I wish I had known they sound best before I bought the Shinkoh's! I would stay away from carbon resistors, though. I have heard too many bad things about them, although they are supposed to sound great in some circuits. Carbon film might be okay, though.
I can see how changing C12 might make an improvement.
What about your experiment with power filtering to avoid motor starting pops?
Peace,
Tom E
Uriah,
That case looks nice. Cost? All holes drilled? Power switch/LED included?
My monoblock cases are crude, cheapo aluminum 7 X 12 X 3, and it's a tight squeeze with a decent xformer and a big input cap off the board. Heatsink is mounted on one end (narrow side) on the OUTSIDE. Power stuff is on the other end. LED is on one long side, input and speaker posts on the other long side. All four sides are used, but internal wiring is all very short and direct.
Are you saving a pair of kits for me? Any extra boards?
Peace,
Tom E
That case looks nice. Cost? All holes drilled? Power switch/LED included?
My monoblock cases are crude, cheapo aluminum 7 X 12 X 3, and it's a tight squeeze with a decent xformer and a big input cap off the board. Heatsink is mounted on one end (narrow side) on the OUTSIDE. Power stuff is on the other end. LED is on one long side, input and speaker posts on the other long side. All four sides are used, but internal wiring is all very short and direct.
Are you saving a pair of kits for me? Any extra boards?
Peace,
Tom E
You get to do the next Ultimate GB Dario!
No thanks... I'm more interested in optimizing BOM...
You're welcome Tom,
BG seems the ULTIMATE cap for C9 but Silmics are still second best for more cost wise builds
So I did but it seems different...
He read your post, he affirms that is using a carbon here that makes the difference since carbon resistors are less 'permeable' to noise coming from ground.
See the attachment, to me it fits better than the Caddock with his heatsink...
He used a 5W Mills.
He read your post, he ordered some Shinkoh to try but he's a bit skeptic, in the past he found them soo sweet but definitevely coloured and not so transparent too...but they can be good for shunt apps.
Takman REX, Kiwame (=Koa SPR) and Koa CF (used in my BOM) are Carbon Film.
Carbon film resistors are reliable and built exactly like metalfilm ones (laser trimmed carbon substrate on ceramic core) and they doesn't suffer most of the problems of carbon composition ones.
Yes, let's wait for feedback about that...
Varistors mitigate the pops problem but it's not resolutive, one question...
Did you connected PGND to the case (directly or via Termistor, cap, diode bridge...)?
I didn't and I suspect this is a big part of the problem...
Attachments
I see, at your home accidents never happen. Nor that they can't, but that luck is always on your side. Congratulations. Not everybody is able to have their eyes on their kids 24/7. They don't need to be babies to suck it, or even suck them to get a shock. Your wife moving it apart to do some cleaning could be the next victim.When probabilities come into play, shhiit happens, but Murphy's law happens too...
But as I said, each one of us are old enough to know what to do. I wish you luck.
On another topic, do you have any picture of your case? Want to see how you disposed your heatsinks.
Dario, you said you have a problem, what is it?
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Update: MyRef_C Ultimate BOM Documentation v1.4
Here it is the last Doc archive for this project. The only one change has been a new update of the BOM of ClaveFremen for the people who is buying only boards (not complete kits) and want to try an alternate high-end BOM. Not better or worse, just different.
MyRef_C_Ultimate_Documentation_v1.4.rar
Regards,
Regi
Here it is the last Doc archive for this project. The only one change has been a new update of the BOM of ClaveFremen for the people who is buying only boards (not complete kits) and want to try an alternate high-end BOM. Not better or worse, just different.
MyRef_C_Ultimate_Documentation_v1.4.rar
Regards,
Regi
Not a real problem, just that the amp is very sensible to spikes, like the ones when the refrigerator starts.
Tom also has a similar annoiance.
Varistors mitigate this.
Not exactly, until this last revision the BOM was identical to the GB one with exception of harder to find parts (PRP, Black Gate) so that it was possible to order all parts from Digikey and Mouser.
In addition some alternative (but reccomended) parts were added (Carbon films in some crtical positions, SBYV27 diodes dor D2,D3).
In this last revision, since I've had a positive feeedback about their use these alternative parts became the only one indicated, along with the MK132 new entry (reccomended alternative).
c9
I wonder how about this cap (solid alum) for C9
VISHAY BC COMPONENTS|228112326221|CAP ALUM ELECT 220UF, 25V, AXIAL | Newark Canada
Have you tried nichicon muse ES before? it supposes to be very close to BG N
I wonder how about this cap (solid alum) for C9
VISHAY BC COMPONENTS|228112326221|CAP ALUM ELECT 220UF, 25V, AXIAL | Newark Canada
Have you tried nichicon muse ES before? it supposes to be very close to BG N
Mmh, the dissipation factor is way higher than Silmics or BGs...
I don't think Muse ES are on par with BGs or even Silmics but I never tried them so mine is only a speculation...
Regi I hope you keep that file going for along time. Its a great resource and it sure is a pain to try to collect all that information from the thread. Nice to have your .rar!
Still plenty to ship but most of US shipments are out as well as Canada and around 10 international.
LDRs are being bagged this weekend and will let me finish the rest of the orders.
Uriah
Still plenty to ship but most of US shipments are out as well as Canada and around 10 international.
LDRs are being bagged this weekend and will let me finish the rest of the orders.
Uriah
OK that might not be a good one, how about this
Digi-Key - 493-3712-ND (Manufacturer - RR71A221MDN1)
I read from here that polymer caps could be very good
I also found this interesting cap comparsion
The last one........until the date!
Never planned to give it up. I am opened to new additions and ideas.Nice to know the kits have started to flight
I am super impressed with the obbligatos. They are soldered in but I wanted to get an idea what it might sound like DC coupled so I took a few alligator clips and wire and bypassed the caps with straight wire. The difference was so hard to tell I had to do it several times. Something changes a tiny bit but is so slight that it makes you think your brain is playing tricks with the sound. The sound actually didnt change but the imaging changed ever so slightly. I could not even describe how it changed. Its there but minimal. Wow is my only words for Obbligatos. I heard they were good but to have almost no imprint on the signal is wonderful.
I listened to Roger Waters - Amused to Death today. Just the first few tracks. In the first track around 2:25-2:35 a large cat growls. It was far far behind my ears. Insane imaging. Of course the recording of that CD helps a lot. Its not as if thats happening with ever disc but it seems magic to get the image wrapped almost all the way around your head.
Uriah
I listened to Roger Waters - Amused to Death today. Just the first few tracks. In the first track around 2:25-2:35 a large cat growls. It was far far behind my ears. Insane imaging. Of course the recording of that CD helps a lot. Its not as if thats happening with ever disc but it seems magic to get the image wrapped almost all the way around your head.
Uriah
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