Thanks OS for clarifying about this amp, some members exibit blown transistors, maybe because of faulty parts. This amp is real God like..!!.. if built properly and nicely...
wow thank you kean, your expalanation will take time for me to fully understand.
but when i build this honey badger i try to match as i could following part
q1/q2
q7/q8
q5/q6
r3/r6
r8/r9
r15/r16
r20/r21
but when i build this honey badger i try to match as i could following part
q1/q2
q7/q8
q5/q6
r3/r6
r8/r9
r15/r16
r20/r21
This is wrong information. Q5/6 are installed facing the same way on the board. Also KSA992 are ECB layout and BC560 CBE layout so it is not as simple to mirror them around as one has Collector center pin and other has a base center pin.
correct niss_man, i have to bend my bc560 leg and isolate using heatshrink tube.
Sorry for wrong info. 😱
To redeem myself , here is a pin for pin equivalent:
http://www.mouser.com/ds/2/149/KSA1015-61942.pdf
KSA1015.
These match the BCxxx's typical characteristics almost exactly. http://www.mouser.com/ds/2/149/BC556-193550.pdf
Use the GR gain group. Buy extra's to match as Keen suggests (.10c at mouser).
OS
To redeem myself , here is a pin for pin equivalent:
http://www.mouser.com/ds/2/149/KSA1015-61942.pdf
KSA1015.
These match the BCxxx's typical characteristics almost exactly. http://www.mouser.com/ds/2/149/BC556-193550.pdf
Use the GR gain group. Buy extra's to match as Keen suggests (.10c at mouser).
OS
That's a great find! They are probably even better, as you can see in the Fairchild BC560 datasheet there is a droop at 1V/50uS, but not for the japanese part. Only drawback is the lower Hfe. I will have to try these in my Kmultipliers whenever I have the chance.
Unfortunately the NPN part, KSC1815 doesn't show Vcesat comparable to the BC550. Possibly, the BC327-40 and KSC1015 are the ultimate BJT pair for low-Vce linearity. If Ft match is desired, BC550/KSC1015 both should still work great. However I want to test this to make sure.
Unfortunately the NPN part, KSC1815 doesn't show Vcesat comparable to the BC550. Possibly, the BC327-40 and KSC1015 are the ultimate BJT pair for low-Vce linearity. If Ft match is desired, BC550/KSC1015 both should still work great. However I want to test this to make sure.
I was a little rusty(wrong info). But since I was going to order some (ksa1015's) , I thought it should be "shared".
OS
OS
Can you see if this is correct?
R7+R8 constrained the dial to block overcurrent settings (did I do it right?)
R29+R30 constrained the dial to block overcurrent settings (did I do it right?)
R27 changed per information in this thread (and from there I just guessed)
Q5,Q6 changed per information in this thread (does it affect Q3, Q4?)
Q14,Q15 changed to avoid severe mismatch (onsemi's low HFE new China fab NPN)
Q16,Q17,Q19,Q20 per information in this thread, 50,50v rails, 8 ohm speaker
Marked all higher current resistors
C4, changed to a reasonable value for higher resolution bass with non-ringing treble
D3 indecipherable, "different compensation options" indecipherable and therefore these need checked out too.
R7+R8 constrained the dial to block overcurrent settings (did I do it right?)
R29+R30 constrained the dial to block overcurrent settings (did I do it right?)
R27 changed per information in this thread (and from there I just guessed)
Q5,Q6 changed per information in this thread (does it affect Q3, Q4?)
Q14,Q15 changed to avoid severe mismatch (onsemi's low HFE new China fab NPN)
Q16,Q17,Q19,Q20 per information in this thread, 50,50v rails, 8 ohm speaker
Marked all higher current resistors
C4, changed to a reasonable value for higher resolution bass with non-ringing treble
D3 indecipherable, "different compensation options" indecipherable and therefore these need checked out too.
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If someone could send me some xSA1015 I could confirm whether they will be best here. That would be nice since Dan has already posted a huge schematic showing them. However I don't expect to see any significant deviation from the datasheet.
Not sure if its the right place,
but i wanted to give this amp a try. However, my PSU is at +-85v on load.. Would maybe be a bit too much when running this on 4r speakers? How would the amp handle it, do i need to change something, maybe add a pair or two of output transistors?
but i wanted to give this amp a try. However, my PSU is at +-85v on load.. Would maybe be a bit too much when running this on 4r speakers? How would the amp handle it, do i need to change something, maybe add a pair or two of output transistors?
For +/- 85Vdc you should have six pairs of plastic output devices for driving four ohm speakers. +/-60Vdc really is the max for the Honey Badger.
It would take a complete redesign. The Honey Badger has an EF2 output stage. Anything bigger should have an EF3. Look into the 6 pair Leach or Leach Double-Barrel.
For driver, 2sc5171 & 2sa1930 are good pairs & have linear hfe ic performance.
For output stage, MJL3281 & MJL1302 OR NJW3281 & NJM1302 are another option.
All of them are available in mouser.
For output stage, MJL3281 & MJL1302 OR NJW3281 & NJM1302 are another option.
All of them are available in mouser.
1. Help us All out. Leave out R9, R10 and R14 then report to us how the circuit you built responds to the upgrades.
2. Earl Muntz circuit improvement methods are a well established design process.
3. Plant the circuit in question in to Spice and give it a run or two and report to
us how the circuit responds. " What if " questions are ideal for Spice examination
and you would be Helping your self and others.
I'm simulating a similar amp, using the BC550 pair for the CCS, KSC1845 for the diff pair, and a simpler two transistor current mirror. R14 at 2.2K does lower overall distortion, but I'm not sure why. R9 makes it worse, and R10 doesn't do much that I can see. I assumed there was a real world application for them that would not be easy to see in a sim.
Found my answers... R9 is to prevent the current sink pair oscillating (found mentioned in Walt Jung's "Sources 101" article in Audioexpress); R14 is for isolating the differential pair form the capacitance of Q7.
It fascinates me that the opamp internals mirror the typical Class AB Amplifier; and there are some fantastic audio opamps now; NE5532 and OPA2134's I favor. I saw a great "tube" video where a person had, I think, three silicons which was putting out some decent volume with minimal parts. And the "Long Tailed Pair" Tube Amp Front-End (12ax7 Phase Inversion) always finds it way into the solid state world by necessity. The concept is the same, just bigger and different parts. It's all the same. We enslave electrons to dance at frequencies that we can see with our ears.