Hello everyone. I'm young and I'm new to the forum. i'm sorry for some writing mistake but i'm using google translate. the reason for my thread is that I built a pre Boz and I have at the output i have a potentiometer of 50k ohm alps, rotating up to 99% all ok, rotating until end of the race at 100% feels a strong bang.I also tried an input potentiometer to reduce the strong signal of the cd, but I input potentiometer produces a slight mass noise during rotation, and at maximum rotation it bumps as in the output potentiometer. I read an article where they say that you can adjust the bias to the symmetrical clipping point, i have a dats with oscilloscope function but i do not know where to connect the two terminals. Thanks in advance for your answers!
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BOZ has a lot of gain, resulting in very high input sensitivity (easily driven into clipping). There are several post on lowering the gain for the BOZ. See BOZ replacement parts post #22 for example.
thank you very much for the answers, and for kindness. I solved the problem. the bang that made the potentiometer rotated to the maximum was like the bang that makes the IRF610 when it lights up and goes off, under a certain voltage. I had set the trimmer to 2.85v at IRF610 SOURCE, and 30v at DRAIN, and maybe I was at the IFR610 ignition voltage limit. then I set the trimmer to 3v to SOURCE, and 28v to the DRAIN, and the potentiometer does not bother anymore.
for the problem of input distortion, i do not know how to use oscilloscope, i hope the 3v adjustment to SOURCE of the IRF610 is fine, otherwise i will test ears or. said this, thank you mr. nelson pass, which gives us these very simple and cheap projects, but very well played. i am very happy with my BOZ and with a little money i have a pre that SUON !!
Aleph 5 diy
Hi mr pass, I made an aleph 5, I ask you kindly if you could suggest me a proper diet. There are many schemes on the internet but I do not know what to use. I thank you in advance and I do my best compliments. If anyone beyond Mr Pass wants to suggest, I'm grateful
Hi mr pass, I made an aleph 5, I ask you kindly if you could suggest me a proper diet. There are many schemes on the internet but I do not know what to use. I thank you in advance and I do my best compliments. If anyone beyond Mr Pass wants to suggest, I'm grateful
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Hello Giovanni, you are coming around to this diy stuff very nicely, good work!
These class A amps run very hot, the case built of of aluminum will conduct heat from the heat sinks to the front panel, and bottom, top and back panels all will become very hot.
Your power capacitors and tiny transformer sit on something in the picture that is white? Hopefully this is not a heat conductive material- looks like it might be wood or nylon or plastic. If so, excellent! You will not conduct the 60C heat from the heat sinks right to your other components. If the frame is steel and not aluminum, even better. In the 2nd picture there are 6 caps across, the 1st and 6th look like they are mounted on the hot bottom panel (not the white dealie), in the next pic they look to be missing?
I have noticed that on my "Extrema" amp, the heat from the heat sinks moves through the metal on every chassis surface (top, bottom, front, back) (everything is aluminum), directly cooking the capacitors and transformers that are mounted on the bottom of the chassis like eggs on a frying pan. I had to loosen the fasteners and pick them up a little bit so they are not touching (or put a heat insulating device in between or something).
So it will be good to assume every surface will be hot is all I'm saying.
Keep up the good work.
These class A amps run very hot, the case built of of aluminum will conduct heat from the heat sinks to the front panel, and bottom, top and back panels all will become very hot.
Your power capacitors and tiny transformer sit on something in the picture that is white? Hopefully this is not a heat conductive material- looks like it might be wood or nylon or plastic. If so, excellent! You will not conduct the 60C heat from the heat sinks right to your other components. If the frame is steel and not aluminum, even better. In the 2nd picture there are 6 caps across, the 1st and 6th look like they are mounted on the hot bottom panel (not the white dealie), in the next pic they look to be missing?
I have noticed that on my "Extrema" amp, the heat from the heat sinks moves through the metal on every chassis surface (top, bottom, front, back) (everything is aluminum), directly cooking the capacitors and transformers that are mounted on the bottom of the chassis like eggs on a frying pan. I had to loosen the fasteners and pick them up a little bit so they are not touching (or put a heat insulating device in between or something).
So it will be good to assume every surface will be hot is all I'm saying.
Keep up the good work.
the air temperature inside the enclosure will be roughly at the average temperature of the many panels connected to the heatsinks.
You have to ventilate the interior to get that air temperature down. The closer you can get the internal temperature to the room air temperature, the cooler the internal components will operate.
You have to ventilate the interior to get that air temperature down. The closer you can get the internal temperature to the room air temperature, the cooler the internal components will operate.
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