Hey all. I need some help with my A38(40) build. So last night I hooked it up to my power supply, 54vdc. But I cannot bias the amplifier and I get about 32vdc at the output. I went over the boards, no broken tracks or shorts, no grounding of any of the semi conductors etc. Not quite sure what is going on, but the 1R 2w resistors get quite warm, not hot but very warm. Please can someone assist. Here is a pic of my build
Hi
I havent. But how would that effect the heating up of the 1r 2w resistors and not being able to bias it
I havent. But how would that effect the heating up of the 1r 2w resistors and not being able to bias it
I was under the impression that I was suppose to short the input pins while setting the bias? Willing to try whatever it takes to get these amps working. Please advise on what to check further
Yes you should short the input but the input ground must be attached to the PSU ground as well.
Dear sir
Please solve my problem in ax14 ampl.
I measure voltage across npn .33 ohm resistance 5.2mV and at pnp .33 ohm resistance is 4.7 mV
Dc off set (out put to grground is 13.5 mV(200mV range)
How can i get equal volts at npn and pnp side emitter resistance.
Please solve my problem in ax14 ampl.
I measure voltage across npn .33 ohm resistance 5.2mV and at pnp .33 ohm resistance is 4.7 mV
Dc off set (out put to grground is 13.5 mV(200mV range)
How can i get equal volts at npn and pnp side emitter resistance.
Everything looks good.
I can't see a problem here.
You can't get exactly same voltages for npn and pnp.
Any of the little transistors, I mean just now. In the negative half-wave amplifier. I would check their pins for resistance with ohm-meter.
hello group members, does anyone have the apex TB7 tone control files that they can share? does it sound good just like the TB3 does it work without problems with the Apex TB1 preamp? I want to have more control options on my two AX11 apex.
apexaudio
Which of your amplifiers would you recommend to build for listening to diverse music at home in a room of 20-40 m2. What amplifier power is needed for such a room and what supply voltage to choose.
For the amplifier I will use an equalizer body as in the photograph (body height 55 mm) and radiators with an area of approximately 600-800 cm2 per channel.
Which of your amplifiers would you recommend to build for listening to diverse music at home in a room of 20-40 m2. What amplifier power is needed for such a room and what supply voltage to choose.
For the amplifier I will use an equalizer body as in the photograph (body height 55 mm) and radiators with an area of approximately 600-800 cm2 per channel.
2x50W 8Ohm\2x100W 4Ohm is the amplifier you are searching for. i suggest Apex Ax14- simple and very nice sounding amplifier.
1. What is the DC voltage (AC voltage) supply should be for 2x50W 8Ohm / 2x100W 4Ohm.
2. What is the min (max) area of the radiator cm2 should be per channel for 50W 8Ohm / 100W 4Ohm.
2. What is the min (max) area of the radiator cm2 should be per channel for 50W 8Ohm / 100W 4Ohm.
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2x28Vac for 4Ohm load or 2x32Vac for 8Ohm load. heatsinks you have should be more than enough - you could post images of them?
