Is this a safety issue, I got her opened up so I can remedy that if needed. What gauge wire is necessary from the mains to the transformer?
Well it certainly is not done normally as it is prone to breaking because of vibration, mechanical stress etc. The gauge depends on the power consumption but in general 0.5 to 0.75 mm2 is OK for a preamplifier and it is still flexible.
Make sure to measure mains voltage in your area and adjust primaries to that. In 230V areas often the 240V settings work out best. I think I see you are in a 115V area and the device is wired for 110V. I would choose 120V primaries I think. Always measure first.
Also please note that connecting the effect generator can lead to undesired effects as the output caps are only 0.47 µF. That means no solid state power amplifiers in practice. It is also possible that the added gain is unneeded, noise is amplified or added, power on/off effects are added and the sources may have way better drive capabilities than the inserted device. Almost any modern DAC with 2V output can drive a 10 kOhm volume potentiometer/power amplifier with a smile and such without any coupling capacitors.
Make sure to measure mains voltage in your area and adjust primaries to that. In 230V areas often the 240V settings work out best. I think I see you are in a 115V area and the device is wired for 110V. I would choose 120V primaries I think. Always measure first.
Also please note that connecting the effect generator can lead to undesired effects as the output caps are only 0.47 µF. That means no solid state power amplifiers in practice. It is also possible that the added gain is unneeded, noise is amplified or added, power on/off effects are added and the sources may have way better drive capabilities than the inserted device. Almost any modern DAC with 2V output can drive a 10 kOhm volume potentiometer/power amplifier with a smile and such without any coupling capacitors.
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I have plenty of of solid core wire in that range, so that's easy enough.
I have measured the mains when I built it and at various time, it's 115v nominal. The voltages in the amp are all nominal as built, so I left it as is. In case I remember correctly the build guide has some more details of wiring the primary. I still want to find the original stuff to scan it to post it here.
What effect generator? A moving magnet cartridge? Interesting point of view, but not too far off base, after all music reproduction from a stereo is an effect. I have used it with both solid state amps and tube amps. Ohhh I see what you did there. Couldn't help yourself could you?
Yes the line stage has something like 19db of gain, but the phono is more in line with the cartridge I use. You did read that I only use it as a moving magnet phono preamp right? I'm sure a moving magnet cartridge can also drive a power amp buy its self with no coupling capacitors. LOLZ.
I have measured the mains when I built it and at various time, it's 115v nominal. The voltages in the amp are all nominal as built, so I left it as is. In case I remember correctly the build guide has some more details of wiring the primary. I still want to find the original stuff to scan it to post it here.
What effect generator? A moving magnet cartridge? Interesting point of view, but not too far off base, after all music reproduction from a stereo is an effect. I have used it with both solid state amps and tube amps. Ohhh I see what you did there. Couldn't help yourself could you?
Yes the line stage has something like 19db of gain, but the phono is more in line with the cartridge I use. You did read that I only use it as a moving magnet phono preamp right? I'm sure a moving magnet cartridge can also drive a power amp buy its self with no coupling capacitors. LOLZ.
You should use stranded wire.
Yes I read you use it as phono preamp but the signal will still go through the line stage and it 2 x 0.47 µF. Please calculate what happens if you connect that to an amplifier with 10 kOhm input impedance and 1 µF input caps (which are in series with the 0.47 µF of the line stage).
If you use it as phono preamp via its Tape Out outputs then it has 2 x 0.22 µF output caps. Also calculate here what happens when connecting to the example power amplifier. Yes that is an effect generator. If one calculates and checks impedances and cap values as things are non standardized in the tube world then one just knows it is off in at least 50% of cases. Well in fact I have never seen it to be right straight away. That's is why tube devices often need to be "married" to other devices. They are not plug and play in combination with todays gear. "Todays" is the last 20 years.
In the light of this it is comical to see people busy with very expensive coupling caps that are chosen too small by default.
Yes I read you use it as phono preamp but the signal will still go through the line stage and it 2 x 0.47 µF. Please calculate what happens if you connect that to an amplifier with 10 kOhm input impedance and 1 µF input caps (which are in series with the 0.47 µF of the line stage).
If you use it as phono preamp via its Tape Out outputs then it has 2 x 0.22 µF output caps. Also calculate here what happens when connecting to the example power amplifier. Yes that is an effect generator. If one calculates and checks impedances and cap values as things are non standardized in the tube world then one just knows it is off in at least 50% of cases. Well in fact I have never seen it to be right straight away. That's is why tube devices often need to be "married" to other devices. They are not plug and play in combination with todays gear. "Todays" is the last 20 years.
In the light of this it is comical to see people busy with very expensive coupling caps that are chosen too small by default.
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Does that matter?!
Read the sad story. A pity all in all. Kondo-san seemed to know what he was doing. Saw a device by him some years ago and it was built quite beautiful.
Read the sad story. A pity all in all. Kondo-san seemed to know what he was doing. Saw a device by him some years ago and it was built quite beautiful.
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I didn't know the story, thanks.
It's pitiful and disgusting but it's commonplace in the business world.