Hi Salas,
perfect, that is exactly the way I feel the last two years when I retired and started to work with the Pass "Apollo" Forum.....every year two or three new rockets (F5 turbo, F6, SIT, M2, J2....) published by the Amp committee in Foresthill.
I reflect to change to the Russian side maybe there is less stress and more vodka.....
O.k. The SIT with the four 3,3 ohm resistors is the best!
NO doubt! All shyness is gone! Precise, powerfully til the bottom. With my quick B1 now a bit bit too sharp wit my Lowthers.
Maybe for Lowthers characteristic I preferred in the past darker sounding amps.....
What a change! Of course I will look for the distortion spectrum, maybe I have dominant k3....
Unfortunately I have now a good hum, is it possible that the placing of the resistorloop in the case nearer to the xformer is hum susceptible? I suppose so... Because I put away the second channel, crippled F4, to lower the current and the hum remained on the same level.
Mike you are right to persist on the try with the bulbs or resistors, they set the level for other solutions like CCS or Mufollower!
Salas please another CCS, still better than the last....
Best Gerd
NO doubt! All shyness is gone! Precise, powerfully til the bottom. With my quick B1 now a bit bit too sharp wit my Lowthers.
Maybe for Lowthers characteristic I preferred in the past darker sounding amps.....
What a change! Of course I will look for the distortion spectrum, maybe I have dominant k3....
Unfortunately I have now a good hum, is it possible that the placing of the resistorloop in the case nearer to the xformer is hum susceptible? I suppose so... Because I put away the second channel, crippled F4, to lower the current and the hum remained on the same level.
Mike you are right to persist on the try with the bulbs or resistors, they set the level for other solutions like CCS or Mufollower!
Salas please another CCS, still better than the last....
Best Gerd
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See solving the hum issue first, if the hum won't go no matter what resistor loop care, its about PSU breakthrough including its higher harmonics. That cascode CCS gives great PSRR up very high, I could present you a single Mosfet one with a TO-220 having a faster gate for mid way results you may prefer, and less components, but try solve the issues when using a resistor first, since you gravitate towards that one. And let me know.
Hi Salas, thanks!
yes I will look for the hum by placing the resistors in other way....
the bulbs have a good place on the top of the case, less hum.
o-k- with your CCS the hum was really absent...
I am still not happy with so much wattage in resistors......
so I am open to try another CCS solution, really!
" its about PSU breakthrough including its higher harmonics." What do you mean by this? I use an 500W xformer and the normal First Watt pcb with 8x22.000uF, not sufficient? even for one channel? of course I combined the two +-24V to 48V.
hi Franz,
I used three 3,3 and some 1,5 and 1 Ohm Vishay metal combined, I got them here
50 Watt, axial bei reichelt elektronik
I suppose this non inductive Vishay should be better......?
RTO 50F 10 - Dickschichtwiderstand 50W TO220 10 Ohm, 5 - Dickschichtwiderstände TO220 bei reichelt elektronik
yes I will look for the hum by placing the resistors in other way....
the bulbs have a good place on the top of the case, less hum.
o-k- with your CCS the hum was really absent...
I am still not happy with so much wattage in resistors......
so I am open to try another CCS solution, really!
" its about PSU breakthrough including its higher harmonics." What do you mean by this? I use an 500W xformer and the normal First Watt pcb with 8x22.000uF, not sufficient? even for one channel? of course I combined the two +-24V to 48V.
hi Franz,
I used three 3,3 and some 1,5 and 1 Ohm Vishay metal combined, I got them here
50 Watt, axial bei reichelt elektronik
I suppose this non inductive Vishay should be better......?
RTO 50F 10 - Dickschichtwiderstand 50W TO220 10 Ohm, 5 - Dickschichtwiderstände TO220 bei reichelt elektronik
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I wrote IF its not due to loop hum then its about PSU breakthrough. Don't be surprised if there might be charging cycle products in heavy PSUs also. Very low impedance goal in such PSU is another thing. SE power stage has no cancellation like PUSH-PULL, plus some gain here. Remains to find out if its due to loop sensitivity for transformer field. I will see about another CCS for you to try soon enough then.
Yes, exactly, Mike and tea-bag! I have three 3,3 and two 1 and one 0,5 to get about 2,5A and 13,9V with 47V . Later in the evening I will change the position of the "resistor loop" I spreaded them generously over the second half of my heatsink. I am quite sure it is the loop getting hum.
But first I have to go for my 82 years old father in law, who is very happy to be visited....
My combined Lowther and Tone Tubby have both 8 Ohm.
But first I have to go for my 82 years old father in law, who is very happy to be visited....
My combined Lowther and Tone Tubby have both 8 Ohm.
if you're chasing exactly same point in time-space conundrum - you need to go in opposite direction
higher load resistance for lower speaker impedance , and vice versa
Thanks,
I tried to wrap my pea brain around the load line, and could not.
So more bulbs, or more resistors, in parallel for sharing of burn load.
One of the reasons I want to get this running soon is to help heat the house!
Gerd, I am still wondering if your using a step-up here now. Very interested.
Thanks,
Gerd, I am still wondering if your using a step-up here now. Very interested.
what do you mean with step- up the xformer I tried at the input?