help...5E3 content

[morroben]

You're right!

Quote:
Originally Posted by Blue Whale View Post
Are you sure that the meter is telling the truth?
Well, I can't be 100% sure. I've checked a couple of known things. My meter reads 123 VAC out of my wall. It reads 8.8 VDC out of a used 9 volt battery I have laying around. Like I said, it does read 3 VAC on pin 2 with no output tubes, which seems correct. The meter has a fresh battery in it. I mean, anything's possible, but I've tried to check the meter as best as I can.

But what I didn't do was check the 9 volt battery on the AC setting of the multimeter. That Energizer 9 volt has 14.9 VAC according to this thing.
Son of a .....

[Blue Whale]

Very good, go enjoy the amp. You know now how to fiddle with the bias setting, so that's som'it to tweak if inclined, otherwise just have a good twang for now and let those 6V6s sing.

Enjoy it.

All the best for your music.

[morroben]

Thanks for all your help. I'm excited to make some noise!

[JohnnyCrash]

I've missed this thread's progress.

Is all well then?

Your MM is reading nearly 15 volts on a 9v battery?! HAHA! Time for a new MM. both of mine are on the skids, so I can relate.

How does she sound?

[morroben]

Yeah...it's reading almost 15 VAC on a 9 volt battery. I feel like an idiot for not thinking of that. I thought I was doing good checking the multimeter against known things, but the DC and AC factor didn't occur to me. I checked AC at the wall and DC on a battery, but didn't think to check for an AC reading on a battery. A new multimeter will be in my future.
You know, it sounds really good right now. With the internal issues sorted out, and fresh tubes, it's sounding sweet.
I mistakenly ordered JJ6V6S power tubes. Will these present any problems compared to the 6V6GTs? They sound great.
As far as the background noise issue, I still think there's more than there used to be, but it's really not that bad. Of course it seemed worse when the amp was sitting on my desk opened up with me sitting in a chair with my face 18" away. Now that I have it closed up and back in it's normal spot in the corner with me 8' away, that noise isn't nearly as noticeable.
I'm loving this amp tonight. My neighbors, not so much.

[Blue Whale]

Originally Posted by morroben

I mistakenly ordered JJ6V6S power tubes. Will these present any problems compared to the 6V6GTs? They sound great.

These modern JJs will present no problems.

Even though folks use these to substitute for 5881s because of the high voltages that these valves can stand, don't think of them as 6L6s. You should still use your 8ohm tap as per the 6V6 setting not your 6L6 tap on your Mission 5E3.

They are just a bit heftier build than the old stock 6V6GT, heavier plates and more like the old 6V6GTA perhaps which stood 14W on the plate, crossed with a lighter weighted 5881, 6L6WGB.

The fact that they sound great in the amp is cool, and that the amp is back on song is fantastic.

[morroben]

Excellent. One last question and I swear I'll leave you alone for a while.
What are the advantages/disadvantages of the two different wiring arrangements for the 6V6s? There's the one that I had originally which is shown in the pictures of my sockets...this one incorporates a 470 ohm resistor into things. Then there's a one that's shown in that last Mission diagram that I posted the picture of. Which is how I have it now. Does it matter? Is one better than other?

[Blue Whale]

Do you mean 750 ohm 3watt screen grid resistors on pins4?

If you plan on sticking with 6V6GT valves then I'd be inclined to leave them out.

However if you wish to use 6L6GC, 6L6WGB or 5881 types then you will need to reinstall those 750 ohm 3watt resistors.

In simple terms they are used because the 6L6 effectively has a lower resistance than the 6V6 thus higher output, so keeps the current in check.

If using 6L6s I'd also be changing the rectifier to a 5V4 which will raise the voltages about 30V over the 5Y3.