Now now... With 5280 posts there is no reading quickly...
Mark sells boards and there is a Wiki wit hthe BOM needed.
Click on the link in GeWa's signiture and you will get to the wiki.
Mark sells boards and there is a Wiki wit hthe BOM needed.
Click on the link in GeWa's signiture and you will get to the wiki.
toroids
KEPha,
The toroids you describe are plenty big enough. Krell had 2 x 400va, with the rail voltage and current ratings implied you can probably run up the idle current to ksa100 levels (2.5A total)...make sure you have huge heatsinks etc...
Stuart
KEPha,
The toroids you describe are plenty big enough. Krell had 2 x 400va, with the rail voltage and current ratings implied you can probably run up the idle current to ksa100 levels (2.5A total)...make sure you have huge heatsinks etc...
Stuart
Whenever Stuart writes.... we listen!! ...... in anticipation....
No pressure Stuart! 😀
PS: Those SA-071's you sent are playing nicely! and because i have 4 of them in paralell (to match the output of the mid/tweet) I need a monster that runs on 95v rails, 50w class-A AND driver 2 ohm loads without breaking a sweat all day long! Basically a Jaccomplifier.
No pressure Stuart! 😀
PS: Those SA-071's you sent are playing nicely! and because i have 4 of them in paralell (to match the output of the mid/tweet) I need a monster that runs on 95v rails, 50w class-A AND driver 2 ohm loads without breaking a sweat all day long! Basically a Jaccomplifier.
K-amps said:
Those are extremely well designed and fully calculated up to the tiniest detail,..........at switch-on they turn red and burn a hole in the floor.
Well KEPha,
If you had your e-mail turned on I could send you the info about the boards. Unfortunately thats not possible so you may have to go P to P.
Mark
If you had your e-mail turned on I could send you the info about the boards. Unfortunately thats not possible so you may have to go P to P.
Mark
mica pads
Does anyone have any mica/thermal/ other pads that I can use or buy from you to electrically isolate and thermally couple my IRFP244's (aleph x) to the heat sink? My guess is that something that fits the Krell plastic MJL output transistors would fit these?
Just doesn't seem right to pay top $$$ to digikey for this. Need about 30.
Does anyone have any mica/thermal/ other pads that I can use or buy from you to electrically isolate and thermally couple my IRFP244's (aleph x) to the heat sink? My guess is that something that fits the Krell plastic MJL output transistors would fit these?
Just doesn't seem right to pay top $$$ to digikey for this. Need about 30.
Free at last, free at last...
I am shipping out the last two kits today. They will be going FedEx priority and should be delivered Friday or Monday.
The Krell KSA-50 GB is now (in a couple of hours when FedEx opens
) closed.
Yeah!!!!!!
The KNOWN issues with ALL the kits:
27 volt Zeners and the 4N48(?) diodes were miss labeled. They have the right printing on the components themselves so check before installation.
JAN Specific kits:
C104 and C109 are smaller values than specified. They should do no harm if installed already, but I will be sending 2 additional caps for each channel. An "add-on" cap that can be soldered to the bottom to bring the value to the correct range, and a single cap of the correct value. If you want the parallel caps just add a second on the bottom. If you are afraid of multiple paths then you will have to desolder the old cap and solder in the new one. Both a minor inconvenience and operation. I am sorry for it though.
Both of the above issues were due to Mouser. They swapped the Zener and diode packaging (verified via a second order of components that were shipped the same way!) and they miss shipped the Jan caps. Must have been a newbie packing or a hang over Monday!
All else should be good, please post here AND email me directly if not. stgrab@yahoo.com
I have a few components left and I will wait for a week to ensure the last kits arrived without issue. Once they arrive I will offer the final parts on a first come first serve basis. These last kits will NOT be replaceable if lost / damaged in shipping. They will be insured so you will get your money back but there will be no component replacements.
The kits will be $75 a PAIR, all components required EXCEPT output devices.
$5 shipping in the US.
$10 shipping REGULAR MAIL out of the US (REGULAR MAIL IS NOT INSURED OR TRACKABLE).
$50 FedEx or UPS which are insured and track able. (I just paid out of pocket $52 x 5 shipments for the original GB; I won't do that again, sorry)
I am shipping out the last two kits today. They will be going FedEx priority and should be delivered Friday or Monday.
The Krell KSA-50 GB is now (in a couple of hours when FedEx opens
) closed. Yeah!!!!!!
The KNOWN issues with ALL the kits:
27 volt Zeners and the 4N48(?) diodes were miss labeled. They have the right printing on the components themselves so check before installation.
JAN Specific kits:
C104 and C109 are smaller values than specified. They should do no harm if installed already, but I will be sending 2 additional caps for each channel. An "add-on" cap that can be soldered to the bottom to bring the value to the correct range, and a single cap of the correct value. If you want the parallel caps just add a second on the bottom. If you are afraid of multiple paths then you will have to desolder the old cap and solder in the new one. Both a minor inconvenience and operation. I am sorry for it though.
Both of the above issues were due to Mouser. They swapped the Zener and diode packaging (verified via a second order of components that were shipped the same way!) and they miss shipped the Jan caps. Must have been a newbie packing or a hang over Monday!
All else should be good, please post here AND email me directly if not. stgrab@yahoo.com
I have a few components left and I will wait for a week to ensure the last kits arrived without issue. Once they arrive I will offer the final parts on a first come first serve basis. These last kits will NOT be replaceable if lost / damaged in shipping. They will be insured so you will get your money back but there will be no component replacements.
The kits will be $75 a PAIR, all components required EXCEPT output devices.
$5 shipping in the US.
$10 shipping REGULAR MAIL out of the US (REGULAR MAIL IS NOT INSURED OR TRACKABLE).
$50 FedEx or UPS which are insured and track able. (I just paid out of pocket $52 x 5 shipments for the original GB; I won't do that again, sorry)
Many thanks, Troy!
Even though I had the help of Mark and Al's boards in this project,and didn't need the parts group buy, I want to thank you for all of us, Troy!
It is your type of volunteer work that makes the diyaudio forum so special. Now I hope you can kick back and enjoy the "fruits of your labors".
Lyndon😀
Even though I had the help of Mark and Al's boards in this project,and didn't need the parts group buy, I want to thank you for all of us, Troy!
It is your type of volunteer work that makes the diyaudio forum so special. Now I hope you can kick back and enjoy the "fruits of your labors".
Lyndon😀
Re: Free at last, free at last...
Troy,
Whoever caused the extra charge should cough it up, if not you should spread the cost to all group buyers and we will pay the diff. Asking for your time for free is one thing, stiffing you with extra expenses is unacceptable!
Please let us know how you want this handled.
K-Concerned.
rabstg said:
Troy,
Whoever caused the extra charge should cough it up, if not you should spread the cost to all group buyers and we will pay the diff. Asking for your time for free is one thing, stiffing you with extra expenses is unacceptable!
Please let us know how you want this handled.
K-Concerned.
Thanks for everything Troy!
I hope that I didn't misscalculate and the missing cash isn't because of me. Anyway, just say the word (or send e-mail) and you'll have the extra money you payed to upgrade the kits to "all included exept outputs".
I REALLY don't like it that you have had to pay for us...
I hope that I didn't misscalculate and the missing cash isn't because of me. Anyway, just say the word (or send e-mail) and you'll have the extra money you payed to upgrade the kits to "all included exept outputs".
I REALLY don't like it that you have had to pay for us...
As I stated in the VERY beginning:
I would order the parts and ship out, BUT all the research and parts selection would be done by the group / thread members.
Well absolutely none of that was feasible. It basically became a trial and error parts investigation. Not for one PCB, but for two.
They are the same circuit (Jan and Al's) yet the majority of the parts were different. Similar part values required different pitch sizes and such.
A lot of components were special order and not returnable.
Basically the whole thing was a cluster f because I didn't dedicate the time from the get go. I basically ordered the parts and started kitting. Well when I test fitted the kits it all fell apart.
That and the fact that I was fighting a lost cause in trying to stay consistent with the Dale RN60 series resistors.
Al in all I am in the red $500-600 on this gig. Is that a big deal for me? No. I don't mind and it was a hell of a learning experience on parts ordering / acquisition.
What I do mind is the fact that the stress from this was the last nail in the coffin of my marriage. 13yrs to the month. The wife was NEVER happy since I moved her to Dallas, and after 5 yrs it had had not improved. This GB and the associated stress (mental NOT financial) and the purchase of another piece of property here in TX drove in the final nail. When we decided to sell the current house and build a new one she knew we would be staying here and this GB became the "excuse" to go back to Louisiana. Well you can take the girl out of the country, but you can't take the country out of the girl.
I apologize for the delay in getting the kits out, the majority of the time was waiting for correct parts. The secondary was test fitting each one over and over. Lastly the OCONUS delay was coughing up the $52 a shipment to ENSURE they arrived as I did not have to luxury of "hoping" the regular mail worked. I needed tracking numbers and insurance to complete what I had started.
The only thing I can assure the GB’ers of is that the parts you rx’ed are at a GREAT discount from what it would cost you to purchase the components yourself. As you can see the new (remainder) of the kits went up $15 a pair and I still don’t think that is at the actual cost but at least I can get ride of the components.
Now in 6 months after I’m divorced and the X is sending me to the cleaners, THEN it will be a financial hardship. As of now it was manageable.
I would order the parts and ship out, BUT all the research and parts selection would be done by the group / thread members.
Well absolutely none of that was feasible. It basically became a trial and error parts investigation. Not for one PCB, but for two.
They are the same circuit (Jan and Al's) yet the majority of the parts were different. Similar part values required different pitch sizes and such.
A lot of components were special order and not returnable.
Basically the whole thing was a cluster f because I didn't dedicate the time from the get go. I basically ordered the parts and started kitting. Well when I test fitted the kits it all fell apart.
That and the fact that I was fighting a lost cause in trying to stay consistent with the Dale RN60 series resistors.
Al in all I am in the red $500-600 on this gig. Is that a big deal for me? No. I don't mind and it was a hell of a learning experience on parts ordering / acquisition.
What I do mind is the fact that the stress from this was the last nail in the coffin of my marriage. 13yrs to the month. The wife was NEVER happy since I moved her to Dallas, and after 5 yrs it had had not improved. This GB and the associated stress (mental NOT financial) and the purchase of another piece of property here in TX drove in the final nail. When we decided to sell the current house and build a new one she knew we would be staying here and this GB became the "excuse" to go back to Louisiana. Well you can take the girl out of the country, but you can't take the country out of the girl.
I apologize for the delay in getting the kits out, the majority of the time was waiting for correct parts. The secondary was test fitting each one over and over. Lastly the OCONUS delay was coughing up the $52 a shipment to ENSURE they arrived as I did not have to luxury of "hoping" the regular mail worked. I needed tracking numbers and insurance to complete what I had started.
The only thing I can assure the GB’ers of is that the parts you rx’ed are at a GREAT discount from what it would cost you to purchase the components yourself. As you can see the new (remainder) of the kits went up $15 a pair and I still don’t think that is at the actual cost but at least I can get ride of the components.
Now in 6 months after I’m divorced and the X is sending me to the cleaners, THEN it will be a financial hardship. As of now it was manageable.
KAS50 vs KAS50s
Hi dear,
what is the difference between the KAS-50 and KAS-50s, I read on the web that the KAS 50 sounds better. On which one is this project based?
K
Hi dear,
what is the difference between the KAS-50 and KAS-50s, I read on the web that the KAS 50 sounds better. On which one is this project based?
K
Firstly there can only be one K on this thread. 😀
This thread is for the original (but second version) KSA-50.
The KSA-50 is a pure class-A power amp. The KSA-50S, is a sustained high bias version that Krell likes to call class-A, but it is not pure Class-A in the classical sense.
The "S" stands for sustained bias, or actually dynamic bias.
This thread is for the original (but second version) KSA-50.
The KSA-50 is a pure class-A power amp. The KSA-50S, is a sustained high bias version that Krell likes to call class-A, but it is not pure Class-A in the classical sense.
The "S" stands for sustained bias, or actually dynamic bias.
KSA50 (Mark 2)
The KSA50s is not a fixed Class A amplifier, it's bias is floating.
Some tests state the s-version to be the better of the 2.
I found the fixed bias KSA50 to be more pleasing, maybe a personal thing. Auditioned a lot of both real Class A and floating bias amplifiers, plenty of those were giant size and mega buck models. The fixed bias ones always had the edge, imo.
The KSA50s is not a fixed Class A amplifier, it's bias is floating.
Some tests state the s-version to be the better of the 2.
I found the fixed bias KSA50 to be more pleasing, maybe a personal thing. Auditioned a lot of both real Class A and floating bias amplifiers, plenty of those were giant size and mega buck models. The fixed bias ones always had the edge, imo.
Troy,
I truly am sorry to hear what the GB has cost you thus far, both emotionally and financially. Each of us involved could have done more to ensure order accuracy, and for that you should allow us to get you to atleast the break-even point for parts/shipping cost.
Thanks for everything!
~Brad
I truly am sorry to hear what the GB has cost you thus far, both emotionally and financially. Each of us involved could have done more to ensure order accuracy, and for that you should allow us to get you to atleast the break-even point for parts/shipping cost.
Thanks for everything!
~Brad
Once again, the financial cost is water under the bridge. Don't sweat it... The only reason I bring it up is sort of a justification for the time it took. By being patient the GB'ers got a much better deal.
Just remember if I join a GB you are running to be patient with me.
So enough already with the outpouring of offers to pay more..
If ya'll have that much money to give away, pool it together and buy me a vacation home on a beach in Italy! 😀
Just remember if I join a GB you are running to be patient with me.
So enough already with the outpouring of offers to pay more..
If ya'll have that much money to give away, pool it together and buy me a vacation home on a beach in Italy! 😀
Ixys Vbe 55-06n07
Does anyone know whether the case of the IXYS bridge module VBE 55-06N07 (data sheet here) is isolated or not isolated? Pic attached.
As you see in the pic, the bottom of the package is metal, I've mounted it to my case with thermal compound and it occurred to me that it may be live! I measured it with a DMM and found open circuits between all pins and the case (swapped DMM leads and results are also the same), did a diode test (again swapping leads, same result) and found no drop between any pin and the case.
Funny thing is that IXYS doesn't have any info on this and the data sheet indicates nothing.
Anyone know this package?
I hate to fire up the xformer without being sure.
edit- going to double post this on the A-X thread... this is holding me up!
Does anyone know whether the case of the IXYS bridge module VBE 55-06N07 (data sheet here) is isolated or not isolated? Pic attached.
As you see in the pic, the bottom of the package is metal, I've mounted it to my case with thermal compound and it occurred to me that it may be live! I measured it with a DMM and found open circuits between all pins and the case (swapped DMM leads and results are also the same), did a diode test (again swapping leads, same result) and found no drop between any pin and the case.
Funny thing is that IXYS doesn't have any info on this and the data sheet indicates nothing.
Anyone know this package?
I hate to fire up the xformer without being sure.
edit- going to double post this on the A-X thread... this is holding me up!
Attachments
Your check between the case to terminals with an ohm meter to was all you need to know. No continuity means its not conected. The IXYS specs do mention 3lv isolation voltage rating and I would bet thats whey they mean... terminal to case mounting.
Mark
Mark
Mr Green,
the isolation voltage on the datasheet tells you that you need not use any insulating material.
I have 2 IXYS power mosfets mounted on 1 heatsink with thermal paste only. Same style package, IXFN200N07, the datasheet of that one also mentions isolation voltage only.
(Its kiddy computer game time overhere, the one i am on now can not resize pictures, i'll post a pic of the sink and mosfets later. Mmm, think i just flushed my rep. by that statement)
the isolation voltage on the datasheet tells you that you need not use any insulating material.
I have 2 IXYS power mosfets mounted on 1 heatsink with thermal paste only. Same style package, IXFN200N07, the datasheet of that one also mentions isolation voltage only.
(Its kiddy computer game time overhere, the one i am on now can not resize pictures, i'll post a pic of the sink and mosfets later. Mmm, think i just flushed my rep. by that statement)