July 1st, 2010 | 
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http://www.oldtonezone.com – the second in a series of videos explaining the basic concepts behind tube amps.
Duration : 0:9:24
http://www.oldtonezone.com – the second in a series of videos explaining the basic concepts behind tube amps.
Duration : 0:9:24
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@Anthony
, yes one common way to ADJUST bias is to measure the cathode current directly or via the voltage drop at a cathode resistor. Anyhow If one says high cathode current = high bias, that means lower negative voltage at the grid. The grid voltage is the cause, the cathode current the effect.
even if it …
@Anthony
even if it gets a tad too techy here
BTW I love your guitar lessons
Greetings from Germany
@spdscherge Yeah I …
@spdscherge Yeah I should have been more specific. Isn’t bias typically measured in terms of urrent though, not voltage?
Take care with …
Take care with wordings like high/low bias, cause bias voltage is always negative. So high bias, like Anthony wrote, means less negative voltage at the grid e.g. -10,0 V instead of -12.5V.
i really want to …
i really want to get a tube amp but idk what i want. any tips?
Yes, but tubes have …
Yes, but tubes have a ’safe’ operating range, so unless you know what you’re doing, it’s best to have the bias set by a tech even when there’s a bias pot provided. Unless of course the bias pot it wired to only allow values inside the ’safe’ range for the tubes.
Okay that makes …
Okay that makes sense. So a bias pot would allow me to dial in what I want as far as power tubes operating. Thanks a lot! Really helpful videos, I watched the whole tube amps collection you have up. I appreciate it.
Bias basically …
Bias basically describes how ‘hot’ the power tubes are operating, high bias causes the power tubes to overdrive more easily, but at the expense of nice clean tones, and low bias makes it hard to overdrive the power tubes, and results in more clean volume.
what does biasing …
what does biasing refer to? i’m saving to buy a classic 30 w/ a bias pot installed, what does that do?
Great videos. …
Great videos. thanks for posting.
Thanks Anthony, …
Thanks Anthony, from a guy who’s played digital modeling amps for about ten years and is trying figure out “real” amps.
Excellent videos… …
Excellent videos…as always
thanks for the …
thanks for the great video, really helpful
it’s good to hear scientific like indepth info
5 stars
Hey Anthony, these …
Hey Anthony, these first two vids are great. Would you mind including something about the pros/cons of having a combo amp over a head/cabinet and vice versa? Thanks.
No, but I’ve modded …
No, but I’ve modded (and subsequently ruined) several
Very true.
Very true.
5 Stars
5 Stars
what kind of guitar …
what kind of guitar do you use?
thanks, you are …
thanks, you are filling in the gaps for me with these videos. have you ever tried to build your own amp?
What about the …
What about the MIDDLE frequency knob. Many amps have that too, and it’s very important in the overall sound. In the live cut you don’t want to argue with the bass guitar over a BASS frequencies no more than you want to argue with a sax or cymbals when it comes to TREBLE (high) freq. So the MIDDLE freq is very important.
Again, another …
Again, another great video. I gave it 5 stars like always.
What is “good” …
What is “good” distortion is somewhat subjective. A couple hints: depending on how much “preamp” distortion you can get (not much with the bjr), the kind of (preamp and power) tubes, the OT transformer, the speaker and of course the guitar, you’ll get very different tones. And as Stevie mentions, preamp and power tube distortions are really different beasts. Some prefer the first, some the other. So maybe the Bjr is just not the right amp for you ?
Thanks for the amp …
Thanks for the amp videos. Very interesting info about amps.
excellent
excellent
Great series so far …
Great series so far Anthony. Look forward to the next installment!
Excellent ! …
Excellent ! Thankyou Anthony.