Electar tube 10 use EL84s?

[bwanab]

After modding my Electar mostly to the specs here, I find that the tone is surprisingly good. However, given that it uses a 6L6/5881, it is still really loud for my intended use (low volume practice). I wonder if anyone could provide any opinions on the wisdom of using a Yellowjacket to fit an EL84 in place of the 5881? It looks like it might be a good match, but I enough of a tube amp mod newbie to look for some guidance from more informed people.

[TD_Madden]

No doubt you'd have to take it out of the cabinet....

[bwanab]

Because of the size of the yellowjacket + tube? I don't think so. The Tube 10 is constructed with the tubes pointing down outside of the wiring part of the cabinet, essentially dangling in back of the speaker which itself is enclosed. There is a lot of room for the 5 inches or so of length that it would physically take.

Or maybe I'm missing your point....

[TD_Madden]

guess I need to take another look at my Tube 10.....yes, it's "outside" the cab, but I thought I remembered that 6L6 using most if its lengthwise space.

[AdmiralB]

Voltage is too high for an EL84 - it's about 450V, IIRC. Since the amp is already cathode biased, you would have to use the Univalve version of the YJ, which has no components in it - it's just a socket adaptor.

EL34 works well in these, the PT seems to be up to the current demands. A 50V zener on the PT secondary center tap is also a good idea, since these creep in to AB operation. That'd get you into EL84-compatible territory too.

[bwanab]

I tried a Svetlana EL34 in mine. I thought it sounded a bit muddy. When I put the stock Sovtek 5881 back in, it sounded much nicer. Is there some trick to getting a good tone with the EL34?

[bwanab]

guess I need to take another look at my Tube 10.....yes, it's "outside" the cab, but I thought I remembered that 6L6 using most if its lengthwise space.

You're right - the yellowjacket is not going to fit. Add that to the voltage being too high....

Thanks everybody for your input. Much appreciated.

[AdmiralB]

Well, I modified the preamp on mine to more of a Marshall spec - brighter than stock. I also have the zener to lower the B+.

[bwanab]

Well, I modified the preamp on mine to more of a Marshall spec - brighter than stock. I also have the zener to lower the B+.

Have you got a schematic?

[AdmiralB]

http://www.freeinfosociety.com/elect...iew.php?id=375

[bwanab]

http://www.freeinfosociety.com/elect...iew.php?id=375

I hate to be dumb but, ... where on that schematic does the 50 V Zener go?

[AdmiralB]

Between the HV center tap and ground. Yellow wire, on the HV secondary.

You need a 50W, 50V cathode-case piece.