Mark,
There was many other values for constant current diodes, also lover voltage ratings diodes at that time when the KSA100 was constructed. However the 1.5 Watt ratings for the 1N5309 diode could not be shifted out for a To 92 device (maximum dissipation of 1W). Also, the 1N5309 is strongly temperature dependent so it could be possible Krell chosen this device out of that parameter. But Im not sure of that, just guessing.
Stuart or PWatts, do you have any thoughts about this? Regards.
There was many other values for constant current diodes, also lover voltage ratings diodes at that time when the KSA100 was constructed. However the 1.5 Watt ratings for the 1N5309 diode could not be shifted out for a To 92 device (maximum dissipation of 1W). Also, the 1N5309 is strongly temperature dependent so it could be possible Krell chosen this device out of that parameter. But Im not sure of that, just guessing.
Stuart or PWatts, do you have any thoughts about this? Regards.
I doubt whether the 1N5309 choice was the result of many pondering sleepless nights from Dan the Man.. as we can gauge from some of the other component choices it's likely to be just what they could lay their hands on. I also doubt whether the J509 was available at that time. Regarding temperature stability, that's not really an issue, just like a few ppm clock deviation in digital stuff. Rapid change (i.e. thermal-induced current jitter) is far more important.
As to the power ratings, even with a 1Vrms input signal the dissipation doesn't exceed 80mW peak so the difference between 1W and 1.5W is irrelevant. Still it may be a good idea to suspend the diode leads a mm or so in the air and not with the body mounted in contact with the PCB for less heat transfer from the substrate from the drivers heating the board.
However, as to all things in audio, the proof of the theory lies in the listening.. Mark if you've time, how about you try to evaluate the differences between the 1N5309 currently mounted, the cheaper 1N5310 and the J509?
Of course a LM317 or REG1117 configured as a current source with a 300ohm resistor and 200ohm trimpot will provide results, but will look horrible on the board. Still, once I have all up&running I plan to measure the differences with my AP but most people will have started building by then already.
As to the power ratings, even with a 1Vrms input signal the dissipation doesn't exceed 80mW peak so the difference between 1W and 1.5W is irrelevant. Still it may be a good idea to suspend the diode leads a mm or so in the air and not with the body mounted in contact with the PCB for less heat transfer from the substrate from the drivers heating the board.
However, as to all things in audio, the proof of the theory lies in the listening.. Mark if you've time, how about you try to evaluate the differences between the 1N5309 currently mounted, the cheaper 1N5310 and the J509?
Of course a LM317 or REG1117 configured as a current source with a 300ohm resistor and 200ohm trimpot will provide results, but will look horrible on the board. Still, once I have all up&running I plan to measure the differences with my AP but most people will have started building by then already.
I agree... Monoblock only. And since these are Chineese made trannys... not the likes of Plitron or other high end trannys you may see lower power at very low impedancees. A 1KVA would be better in a monoblock, a 2KVA in a stereo job. You'd have a better chance with this one Its closer to the VA rating of the original Krell tranny.
You don't have to deal with him through E-Bay... you can buy direct . Look at the AN8440. I wonder if we should do a GB of these....? Since it also has two other 18 volt 2 amp windings that could easily supply the relay circuits and such this would be the one to get, not the E-Bay unit.
You don't have to deal with him through E-Bay... you can buy direct . Look at the AN8440. I wonder if we should do a GB of these....? Since it also has two other 18 volt 2 amp windings that could easily supply the relay circuits and such this would be the one to get, not the E-Bay unit.
Hi,
45 + 45Vac is far too high for a Klone.
I believe that KSA100 used 37 + 37Vac.
The 8440 is about 37Vac when connected to 120Vac but is only 730VA (800-72) so the voltage will fall below spec.
My original look back at the antek data must have misread the information but the same message "too small" still applies.
Edit,
I cannot see Mark G's posts.
It says he is on my "ignore list", but I have never set up an ignore list.
Is someone mucking about with my profile?
How do I set is back?
45 + 45Vac is far too high for a Klone.
I believe that KSA100 used 37 + 37Vac.
The 8440 is about 37Vac when connected to 120Vac but is only 730VA (800-72) so the voltage will fall below spec.
My original look back at the antek data must have misread the information but the same message "too small" still applies.
Edit,
I cannot see Mark G's posts.
It says he is on my "ignore list", but I have never set up an ignore list.
Is someone mucking about with my profile?
How do I set is back?
What was the reasoning behind the Q9,10,11,12 original's (Toshiba 2sa968, 2sc2238) verses the BOM's MJE15034/35 change?
The 2s's are 100 Mhz vs. 30 Mhz for the MJE's
Shopping around I noticed the 15035's were backorderd (now available this week) with plenty of the 15034's to be instock. That means your likely to get different batches and I have plenty of the Toshiba's already for those particular drivers.
On Semi sample is 5 pcs only and not enough for 3 mono blocks
I'll be using the T03 MJ15024/25 as output's and this might work out better in the end.
Any comments?
Regards
David
The 2s's are 100 Mhz vs. 30 Mhz for the MJE's
Shopping around I noticed the 15035's were backorderd (now available this week) with plenty of the 15034's to be instock. That means your likely to get different batches and I have plenty of the Toshiba's already for those particular drivers.
On Semi sample is 5 pcs only and not enough for 3 mono blocks
I'll be using the T03 MJ15024/25 as output's and this might work out better in the end.
Any comments?
Regards
David