Hi. I just joined DIYA because I got it in my head that this amp was something I wanted to build.
But I was reading the first few pages of this thread, and it occurred to me that I am a bit flaky, and probably need an amp with a more robust protection scheme than just remembering to be careful. Did anybody ever come up with any DC/undercurrent protection for one of their builds?
But I was reading the first few pages of this thread, and it occurred to me that I am a bit flaky, and probably need an amp with a more robust protection scheme than just remembering to be careful. Did anybody ever come up with any DC/undercurrent protection for one of their builds?
AMP CONTROL BOARDS – Virtual Zero Audio Store
These boards are discussed here. How to build a 21st century protection board
These boards are discussed here. How to build a 21st century protection board
Are you asking from a protection solution for DC or a current limiter to protect against shorting or overdriving the outputs?
There are plenty of protection solutions for DC offset that are often separate from the amplifier circuit (The DIYAudio store sells a solution). However, if you are looking for a current limiter to protect the output devices from being overdriven or shorted, then you would typically need something built into the amplifier circuit.
There are plenty of protection solutions for DC offset that are often separate from the amplifier circuit (The DIYAudio store sells a solution). However, if you are looking for a current limiter to protect the output devices from being overdriven or shorted, then you would typically need something built into the amplifier circuit.
This amp is pretty darn robust. It will take a real beating. I have driven my poor 5ch honey badger hard and beound a lot over the past year. It just smiles and gives me a bloody kick in the face 🙂
(all this given it is build kind of right)
(all this given it is build kind of right)
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thx 🙂 That is my favorite build. The time and money spend on that build was high. But the result was outstanding.
The 21st Century Protection system does provide overload protection, as well as DC offset detection, overtemp and power loss detection. Overload is easy to detect by measuring voltage drop across a pair of emitter resistors.
How to build a 21st century protection board
It also provides for soft start and if you have tubes a warm-up delay. Also if you buy the power supply boards from them, it disconnects the power supply from the outputs when a fault is detected. Also blinks the power LED to let you know what fault it has.
Having trouble finding Q7 and Q8 KSC1845 short of waiting 210 days on Digikey or 300 days on Mouser. Any alternatives for this part. I have not found any references to swapping this part.
npn's like mpsao6 or ztx450 will do for q7/q8...you have a lot of other options...
https://www.onsemi.com/pub/Collateral/MPSA05-D.PDF
https://www.diodes.com/assets/Datasheets/ZTX450.pdf
https://www.onsemi.com/pub/Collateral/MPSA05-D.PDF
https://www.diodes.com/assets/Datasheets/ZTX450.pdf
Getting the Badger together.... This will be a dual mono version obviously, the LEDs for the power will be the badgers eyes. I found a cool little decal, I think it's going to work nicely. I almost didn't use it as some of the stuff can get kinda puerile, but "What's up Doc?' 😛
The speaker boards are just there for place holder, I'm going to swap them out for another design.
The speaker boards are just there for place holder, I'm going to swap them out for another design.
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back ordered until June
For Q3, 4,7, and 8. RS Components lots of 200 back ordered until June 7. Digikey 200 days, Mouser Oct 2021🙁
For Q3, 4,7, and 8. RS Components lots of 200 back ordered until June 7. Digikey 200 days, Mouser Oct 2021🙁
I think the total open loop gain will still be high enough with these substitutes, hence presume that no passive components need to be recalculated. But I'm not the wisest one here, so others may contradict.
Best regards!
Best regards!
MPSA06 is also backordered
ZTX450 is available but has a Vceo of only 45V. Problematic for Q7/8 with 60V rails.
Is looks like AmpsLab has KSC1845 available in lots of 20.