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Help with tube specs

I will be getting a pair of EML 300b "mesh pate" tubes in a few days.

EML warns that the meshes should be run between 22-28 watts of dissipation with the closer to 22 the better and 28 MAX.

The amp I will be using them in is fine but I have another amp I'm not sure of. It's a Welborne 300b DRD. I was able to find this much:

">>>I have a Welborne manual for the 300B DRD and there are no voltages given in the manual. However, the original owner wrote his voltages on the schematic after he built the amps. He shows 505V on the plate and 190V on the cathode for a plate voltage of 315V. He also shows a cathode current of 65mA. So that means you have a plate dissipation of 20.5W.<<<

I also got this:

" The 300b mesh will not tolerate 500v on the plate. Even with a reduced dissipation on the tube, the tube won't last!"

I also read that with the tube drawing 1.4 amps at 5 volts (7 watts) you would add this to the 20.5W for a total of 27.5W. At least that keeps me in the 22-28 realm.

Can anyone help me sift thru this info? Opinions as to "how safe" it would be would be appreciated.

In the meantime, I will only run it in the safe amp for warranty purposes but would eventually like to try it in the DRD and would hate to eat the money if it's a mismatch.

Thanks.
onemug

Showing 3 responses by isochronism

isochronism
2,893 posts
 
Hi Onemug,
I always agree with Al's and Charles's opinions wholeheartedly.
I am also a devote of the 300b as is Charles, and with his take on his Tak's, I believe!!
I currently use a pair of RP's with a secondary pair in the waiting as I got a nice deal on a quad set.
Starting fresh, I would go with your choice of EML true Mesh Plate. Very interesting.
I also have a pair of 45 amps which need more immediate attention on power tube replacement. EML is where I will go.
isochronism
2,893 posts
 
I recall in past posts of your general system set-up, which I always felt was excellent. In fact, I do plan to do similar as I have a pair of JBL 4550s with original HF driver/fiber horn etc, which I have had for years put away.
I am in a small apartment and will move someday and plan to also employ active xo. Your's must sound really nice!! The 45 amps came with TJs and RCA/Cunningham which I am currently using. The EML Globe limited looks very interesting.
I just switch back and forth from 300B to 45 amps every couple weeks. Sure do like them both. Using Beauhorn Virtuosos, btw.
isochronism
2,893 posts
 
Mesh on top and bottom!! Very nice indeed!!
I have heard/read nothing but good reports concerning EML.
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