For the Marantz 9's. How hard does it push the small signal tubes? In particular the 6DJ8's?
How is the Marantz pushing 310 volts on the plate when the tube itself is rated for 140 volts maximum? I assume it's referring to plate supply voltage (= peak forward plate voltage?) which is much higher at 550 volts.
If I were to use a near equivalent tube of 165 volts max plate voltage but a peak forward plate voltage of 330 volts would it work? 1 watt per plate dissipation. Last thing I would want to do is risk blowing the amp.
How is the Marantz pushing 310 volts on the plate when the tube itself is rated for 140 volts maximum? I assume it's referring to plate supply voltage (= peak forward plate voltage?) which is much higher at 550 volts.
If I were to use a near equivalent tube of 165 volts max plate voltage but a peak forward plate voltage of 330 volts would it work? 1 watt per plate dissipation. Last thing I would want to do is risk blowing the amp.
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The max plate voltage is plate-to-cathode voltage, never 'just' a number.
Always with respect to another node.
That's why multimeters have two leads ;-)
What's the Vak in that amp?
Jan
Always with respect to another node.
That's why multimeters have two leads ;-)
What's the Vak in that amp?
Jan
I wouldn't know the Vak, I'm not that knowledgeable about this stuff but the service manual is here: http://zilla.li/Resources/PDF/Marantz_8B_9/Marantz_9_Service_Manual.pdf
And here is the tube I wish to use:
And here is the tube I wish to use:
I can do that, still waiting on the Marantz's to arrive in the mail. I am doing some tube shopping for when they arrive. I can be patient though and wait if that's the best way of knowing.
It's not that. NOS tubes are much cheaper than paying $30-70 each for EH or Gold Lion new production. Also, not sure how long these new production tubes last anyway. I tend to listen for 8 hours a day, it's not just music but tv as well so tubes won't last as long for me.
I can test with a uTracer and check for shorts with a multimeter. I have no way of testing for gassy tubes but I am buying from a seller that tests for that.
I can test with a uTracer and check for shorts with a multimeter. I have no way of testing for gassy tubes but I am buying from a seller that tests for that.
If I use that (pin 1 = A, pin 3 = K) and look at the tables posted in post # 1, it seems clear that Vak is about 150V give or take a few.
So no problem.
Jan
So no problem.
Jan
So I would be safe with these tubes despite the lower Peak Plate Forward Voltage/Plate supply voltage.
Awesome, thanks!
Awesome, thanks!
As noted, the tube max anode values are not with respect to ground, they are with respect to the cathode.
The reason this is not spelled out is that it is undertood that the tube only sees what voltage is between the anode and the cathode.
The tube has no idea what ground is.
So it isn't spelled out but you need to internalize it for future understanding/discussion.
Jan
The reason this is not spelled out is that it is undertood that the tube only sees what voltage is between the anode and the cathode.
The tube has no idea what ground is.
So it isn't spelled out but you need to internalize it for future understanding/discussion.
Jan
According the schematic, V3 plate is at 300VDC and cathode is at 132VDC so 300-132=168VDC. That triode is operating at 168VDC. Each triode of that V3 is running at 1.72mA current.
