Looks like your pin 8 values slightly exceed the 50v recommendation. Dropping your b+ a little to like 250 should get you within the recommended specification.
Its an all in one board right? Increasing the value of the last power resistors should get you there.
You know how many mA you are running and how many volts you should drop. Assume you are running 40 mA total and you need to drop 50 v. R=V/I so you need to add 1250 ohms to each rail.
Its an all in one board right? Increasing the value of the last power resistors should get you there.
You know how many mA you are running and how many volts you should drop. Assume you are running 40 mA total and you need to drop 50 v. R=V/I so you need to add 1250 ohms to each rail.
Your other option is to run the tubes a little hotter. Crank them up to 10 ma or so.
Another fix may be to lift the heaters a little higher although I have never tried that. Go to b+/3 by modifying your divider values.
As long as they aren't like $100 a piece tubes at anything you are probably close enough.
Also too lazy to search but are you running the heaters at 12.6-series or 6.3-parallel? Running at 12.6 mightgive you the extra headroom too.
Another fix may be to lift the heaters a little higher although I have never tried that. Go to b+/3 by modifying your divider values.
As long as they aren't like $100 a piece tubes at anything you are probably close enough.
Also too lazy to search but are you running the heaters at 12.6-series or 6.3-parallel? Running at 12.6 mightgive you the extra headroom too.
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So are you running the 6dj8 at the input and 6cg7 at the output?
Do me a favor measure pin 4 and 5 at each pin and then either 4 to 5 from v1 to v2 or vice versa.
I tried this combo with my dual mono aikido and could not get the heaters to balance between v1 and v2. Although I think I was pushing the limit of my xformer. 6dj8 draws some current.
Do me a favor measure pin 4 and 5 at each pin and then either 4 to 5 from v1 to v2 or vice versa.
I tried this combo with my dual mono aikido and could not get the heaters to balance between v1 and v2. Although I think I was pushing the limit of my xformer. 6dj8 draws some current.
OK......so I have changed the input tubes out for 6DJ8's.
They have been running this way for a few days now.
I have noticed much greater focus with these tubes but I have also noticed that they don't seem to have as much low bass.
Is this something that I can adjust with some resistor value changes?
The bass IS there but it just doesn't seem to be as full and noticeable as it was with the 6CG7's.
It's really noticeable with a heavy kick drum, it's just "MEH", what is there is nice sounding, it's just hard to explain.
It even almost sounds like the bass has been shoved out to the sides.
My room modes on either side of my room are much more pronounced with these tubes.
They have been running this way for a few days now.
I have noticed much greater focus with these tubes but I have also noticed that they don't seem to have as much low bass.
Is this something that I can adjust with some resistor value changes?
The bass IS there but it just doesn't seem to be as full and noticeable as it was with the 6CG7's.
It's really noticeable with a heavy kick drum, it's just "MEH", what is there is nice sounding, it's just hard to explain.
It even almost sounds like the bass has been shoved out to the sides.
My room modes on either side of my room are much more pronounced with these tubes.
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Well....Maybe not, I used my setup on a friends speakers and the low bass is there but the midbass has little authority, it's there it's just underwhelming.
I'm going to try the 6CG7's again and see how it goes.
My friends Emotiva CD player has WAY more output than my computer or my Ipod so maybe I don't need more gain I just need a source with more balls.
I'm going to try the 6CG7's again and see how it goes.
My friends Emotiva CD player has WAY more output than my computer or my Ipod so maybe I don't need more gain I just need a source with more balls.
I have found a way to describe what I have been hearing.
Bass at the top of Sub and the bottom of Mid has pop but not much thud to go along with it.
I have swapped the 6CG7's in place with no other modifications and I have gotten that thud back.
This must just be the character of that specific 6DJ8, It has focus & clarity at the expense of bass fullness.
Bass at the top of Sub and the bottom of Mid has pop but not much thud to go along with it.
I have swapped the 6CG7's in place with no other modifications and I have gotten that thud back.
This must just be the character of that specific 6DJ8, It has focus & clarity at the expense of bass fullness.
You'll find subtle tonal difference among 6DJ8s and equivalents such as 6922/ECC88/6N23P.
Amperex orangle globe A-getter type 6DJ8s and ECC88s have quite heavy bass. Telefunken ECC88s are very well balanced. Soviet 6N23P are very clear in sound without heavy bass, which I like the most. Even among those you'll notice differences based on which factory they come from.
Amperex orangle globe A-getter type 6DJ8s and ECC88s have quite heavy bass. Telefunken ECC88s are very well balanced. Soviet 6N23P are very clear in sound without heavy bass, which I like the most. Even among those you'll notice differences based on which factory they come from.
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