And Mouser replys.....
SHIPPING INFORMATION
TO EXPEDITE YOUR ORDER, WE UPGRADED IT TO SHIP UPS 2nd DAY AIR
AT A TOTAL COST OF $15.48. MOUSER PAID FOR THE UPGRADE
AND ONLY CHARGED YOU THE UPS GROUND SERVICE RATE OF $8.47!
FOB: SHP POINT
Even though I won't be home to receive it! Oh well... Brenda can babysit them till I get back.
Mark
SHIPPING INFORMATION
TO EXPEDITE YOUR ORDER, WE UPGRADED IT TO SHIP UPS 2nd DAY AIR
AT A TOTAL COST OF $15.48. MOUSER PAID FOR THE UPGRADE
AND ONLY CHARGED YOU THE UPS GROUND SERVICE RATE OF $8.47!
FOB: SHP POINT
Even though I won't be home to receive it! Oh well... Brenda can babysit them till I get back.
Mark
Mark A. Gulbrandsen said:
I've heard of baby sitters and dog sitters but diode sitters? 😉
I shopped around town and came up with zip on the 1N5309 so Mouser will ship them along with a few other KSA100 parts. For me the full BOM for two boards stuffed including PCB cost is around $335.00 CND. The only extra cost was that I purchased 100 each of the 2SC2240 & and 2SA970 around $50.00
Mouser: $75.00...1N5309 + a few R's & some On Semi T's
Digikey: $150.00...most of the semi's + electrolytics & LED stuff
Parts Connexion: $60.00...R's & solen caps
Mark G./P. Watts Boards: $50.00
Not a bad start in my books but I sure wish the metal work and power supplies were not so hard to conjure.
Cheers,
Shawn.
where can I buy electronic parts?
Hi everyone,
I am new immigrant to canada.
i live in toronto now,
I am very interested in ksa 100mk2
where can I buy electronic parts in toronto?
Are there any eletronic parts market in toronto??
I'd like to buy some high-quality and high-end parts.
thanks
😕
Hi everyone,
I am new immigrant to canada.
i live in toronto now,
I am very interested in ksa 100mk2
where can I buy electronic parts in toronto?
Are there any eletronic parts market in toronto??
I'd like to buy some high-quality and high-end parts.
thanks
😕
The boat has left.....
Thank Patrick for the clarification......I'm a little late but not to worry!
Thank Patrick for the clarification......I'm a little late but not to worry!
TomWaits said:
Shawn,
what position in the Krell Stereo Amplifier race are 1500VA toroids with a $40 tag worth ?
Toroid pictures when the broken back mountain mailman arrives.
jacco vermeulen said:
Is that a "Brokeback Mountain" (a movie) joke? 😉
Yep. 
A mailman on a mule, carrying 2 huge donuts.
Speaking about good fortune, bought the toroids from 2 individuals, on the same day.
Same size, same secondaries voltage. I'll need Fluoxetine, if the brand is even the same.
Call me Jacco (secondary) Twist.
A mailman on a mule, carrying 2 huge donuts.
Speaking about good fortune, bought the toroids from 2 individuals, on the same day.
Same size, same secondaries voltage. I'll need Fluoxetine, if the brand is even the same.
Call me Jacco (secondary) Twist.
jacco vermeulen said:what position in the Krell Stereo Amplifier race are 1500VA toroids with a $40 tag worth ?
I still have 3-4 pieces of 44-0-44 1000VA but are you telling me you have some 1.5kVA's for sale?
With the 44-0-44 I'll have 60 volt rails, higher output potential and heat issues but to get ready for it I jumped up the voltage for most of the electrolytic's and the rest of the caps are 250V, 500V etc.
I'm wondering if any of the resistor values, especially on the pre and VAS section, would require tweaking to properly accommodate the +/- 60 volts DC? Any thoughts guys?
Race? What race? I'm slow poking the the KSA50. It is a shame but it is all there, case and all, just crying for attention. I have to finish the 50 before sinking my time and teeth into the 100. Also I need more experience building, so my theory is if I get the 50 good then the 100 will be better as I gain more experience with the metal work.
The concept for the metal work I have for the KSA100 could put me back an easy $1000.00!!! If the spring work schedule continues like it is now I may do it but still it is hard to justify. If not I'll go with fans and a steel coffin just like every other amp that we have all seen before.
We'll see...my ideas sometimes change like the weather. 🙂
Jah,
Shawn.
Newbie
Hi Everyone!
Call me Wi, a newbie to this project. Seriously, this project seems really interesting and it's great that you guys have gone this far to get it flying off the ground.
I saw some post re: group pcb buy and diode buy.
Question:
1. Can I still opt-in for the buy or is it too late now?
2. I haven't gone through the thread completely, but is there components list for the project (KSA 100 mkII clone)?
Thx!
-W
Hi Everyone!
Call me Wi, a newbie to this project. Seriously, this project seems really interesting and it's great that you guys have gone this far to get it flying off the ground.
I saw some post re: group pcb buy and diode buy.
Question:
1. Can I still opt-in for the buy or is it too late now?
2. I haven't gone through the thread completely, but is there components list for the project (KSA 100 mkII clone)?
Thx!
-W
Wi,
The boards have been ordered and delivered to the group purchase members. I believe Mark A. Gulbrandsen is now serving people in the waiting list. You might want to check with him. If there is enough interest that could be a new production run.
There is a Wiki page with construction info here:
http://www.diyaudio.com/wiki/index.php?page=Add+your+names+join+the+group+buy
Yesterday I updated it with the URL to the latest (known) Bill Of Materials.
The boards have been ordered and delivered to the group purchase members. I believe Mark A. Gulbrandsen is now serving people in the waiting list. You might want to check with him. If there is enough interest that could be a new production run.
There is a Wiki page with construction info here:
http://www.diyaudio.com/wiki/index.php?page=Add+your+names+join+the+group+buy
Yesterday I updated it with the URL to the latest (known) Bill Of Materials.
From Pwatts KSA100 wiki:
The amp should work OK at lower supply voltages, but for optimal performance they should be >42V. This is because of the 39V zeners used for the LTP's resistor current sources. Try to keep it between 48-52V voltage though.
Can I get around this with 60 volt rails or am I just heading straight for trouble? Tweak or lower rails are a must?
Shawn.
The amp should work OK at lower supply voltages, but for optimal performance they should be >42V. This is because of the 39V zeners used for the LTP's resistor current sources. Try to keep it between 48-52V voltage though.
Can I get around this with 60 volt rails or am I just heading straight for trouble? Tweak or lower rails are a must?
Shawn.
Hi Mark,
Just sent you $43 for the 10 1N5309s.I received my 4 boards today they look great thanks for the hard work you put into them.
Regards
Anthony
Just sent you $43 for the 10 1N5309s.I received my 4 boards today they look great thanks for the hard work you put into them.
Regards
Anthony
higher rails...
Shaun,
The rails you are contemplating are not intrinsically out of the question, you just have to compensate in your heatsinks or perhaps fans etc. Assuming you keep the idle current at the level required for 100W class A, the heat output will increase linearly with the voltage.
Stuart
Shaun,
The rails you are contemplating are not intrinsically out of the question, you just have to compensate in your heatsinks or perhaps fans etc. Assuming you keep the idle current at the level required for 100W class A, the heat output will increase linearly with the voltage.
Stuart
Thx + Separate Items
Thx for the reply.
I also notice the following: "there are no output boards made as part of the pcb".
Another questons:
1. Does "output boards" consist both "output relay module" and "output stage"?
2. I assume "power control module" is not included in the main board either?
Thx!
-W : )
Thx for the reply.
I also notice the following: "there are no output boards made as part of the pcb".
Another questons:
1. Does "output boards" consist both "output relay module" and "output stage"?
2. I assume "power control module" is not included in the main board either?
Thx!
-W : )
Since there is no standard heat sink that everyone can buy for this project, some will use forced cooling, as in the original Krell KSA-100, others will use passive cooling, which requires close to 40 lbs of a well designed extrusion. With so many different ways of physically installing the power transistors, making output boards would have been pointless.
The additional modules can be built on standard perforated boards, turret terminals attached to the heat sinks, turret boards, etc. They may be also replaced by other solutions, if you decide to brew your own.
😉
The additional modules can be built on standard perforated boards, turret terminals attached to the heat sinks, turret boards, etc. They may be also replaced by other solutions, if you decide to brew your own.
😉
Re: higher rails...
True, I don't plan on trying to get more class A out of it, so if my rail voltage is higher, then I should be able to acheive a similar result by lowering the bias current?
I can easily purchase 2 watt versions of the 39volt zeners too.
Shawn.
Stuart Easson said:
True, I don't plan on trying to get more class A out of it, so if my rail voltage is higher, then I should be able to acheive a similar result by lowering the bias current?
I can easily purchase 2 watt versions of the 39volt zeners too.
Shawn.
Hi Tom,
as said there is nothing wrong with changing the Vrail voltage.
But you must go back to the schematic and re-calculate the dissipations in all the devices.
A few that particularly need attention are
r11&12
q9&10
q14 to 17
qoutputs
do not change the zener disipation. Instead change the feed resistor wattage and resistance (or parallel a pair of higher value).
If you want 100W of ClassA into 8r (5Apk) then you must maintain Iq>2.5A plus a small margin i.e. ~=2.6A
At 60V the dissipation will go to 300W instead of 260W, not an amp killer, but either higher running temperature (=lower SOAR) or bigger sink dissipation.
Are you sure 44Vac gives only 60V? I would expect +-62Vdc (312W) when biased to 2.6A.
To all
What voltages exist around the FETs?
I think the gates are sitting at about 31V.
That would put the source @ about 27V. Can anyone confirm? I trying to establish what happens to Q5 & D5 @ alternative Vrail and when signal is passing.
Is q11 & q12 a cascode or simply a constant voltage dropper? It looks just like a fixed voltage Vbe multiplier.
I think it drops a constant 1.5V to 1.7V irrespective of signal or Vrail.
as said there is nothing wrong with changing the Vrail voltage.
But you must go back to the schematic and re-calculate the dissipations in all the devices.
A few that particularly need attention are
r11&12
q9&10
q14 to 17
qoutputs
do not change the zener disipation. Instead change the feed resistor wattage and resistance (or parallel a pair of higher value).
If you want 100W of ClassA into 8r (5Apk) then you must maintain Iq>2.5A plus a small margin i.e. ~=2.6A
At 60V the dissipation will go to 300W instead of 260W, not an amp killer, but either higher running temperature (=lower SOAR) or bigger sink dissipation.
Are you sure 44Vac gives only 60V? I would expect +-62Vdc (312W) when biased to 2.6A.
To all
What voltages exist around the FETs?
I think the gates are sitting at about 31V.
That would put the source @ about 27V. Can anyone confirm? I trying to establish what happens to Q5 & D5 @ alternative Vrail and when signal is passing.
Is q11 & q12 a cascode or simply a constant voltage dropper? It looks just like a fixed voltage Vbe multiplier.
I think it drops a constant 1.5V to 1.7V irrespective of signal or Vrail.