[Welly Wu]

Hey all! This one goes out to Tuberoller himself as well.

You may or may not care that I'm saving up for a Ah! Njoe Tjoeb 4000 CD player with all the upgrades in a little over a year from now. I'm reading a bunch of stuff on upscale audio's website. This is completely new to me. What is tube biasing and matching? What are the do's and don'ts about hybrid solid state / tube sources that are not stated in the upscale audio website? Remember, my questions pertain not to tube based headphone amplifier but the Ah! Njoe Tjoeb 4000 in terms of safety warnings and procedures. I read that there is enough voltage going through this cd player that if I'm not careful, well, I won't be posting around these parts no more (yes, you may cheer and laugh now). What does that mean with respect to the 4000? I did a search but not much safety related information came up with respect to the hybrid tube / solid state player that I am interested in. How would I go about safely changing tubes should I be inclined to do so without killing myself? In changing tubes around, would I have to do tube biasing and matching each time? Thanks!

 

[Budgie]

I will see if I can find some info on the Ah Tjoeb 4000, but I don't think there is anything to be concerned with.

(later that day-)
You will not need to adjust bias, when changing tubes. The small signal tubes will be fixed bias and do not need to be adjusted when changed, in that type of circuit. When changing the tubes, power down the player first, always. Never swap the tubes when powered up. If you want to be extra safe, unplug it from the outlet. If you handle the tube by holding the glass you will be safely insulated from the voltage, just don't let your fingers get down into the circuitboard or pins. Some people wear gloves when handing tubes to keep finger grease off of them, but it isn't really neccesary with low power tubes. Be warned, they do get hot enough to burn fingers.

I hope that helps.

 

[ServinginEcuador]

Tube matching is when you try and team up a pair of tubes that are very close on the amount of amplification that they have. That way the sound is equal in both channels.

Just one piece of advice Welly, don't get your heart set on anything a year in advance. Things change and progress so rapidly that in one year's time this unit could be surpassed quite handily by other units for less money and better sound. If you just stock pile the money and do your research around this time next year you will be much better served. Especially with the SACD II Sony is trying to force on us.