Are these the same tubes as the EL84-S that Groove Tubes carries? Slovakian origin?
The EL84S is the JJ EL84
The EL84Y is the Ei EL84
The EL84R is the Sovtek EL84
In all the above, they are run and distortion matched rather than statically matched. This means they are tested over the entire operating range.
As a bit of side info ....
Many folks do not match, in any way, EL84 tubes. Mesa EL84 tubes as an example are not rated or matched. Mesa does do some great matching though on their 6L6 and EL34 tubes.
Most EL84 amps are cathode biased. Some folks think the Fender Blues Jr is a cathode biased amp as it has EL84 output tubes. This is not the case. It is a class A/B Grid Biased amp. El84 tubes were chosen for that amp as they were less pricy for Fender than 6V6 tubes.
The EL84R is what is found in most high production EL84 amps. These are a robust tube but replacing them with most anything else will really open up an amp as these make an amp (to my ears) sound as if a blanket was placed over the amp. But ... they are a reliable tube.
The EL84Y is a good sounding tube but the least reliable of any of the EL84 types. On an amp with a split bias such as a Mazerati or RxEX, a cool trick is to use a duet of these on one side and a duet of the EL84S on the other side. The duets in these amps are side pairs, not inner and outer duet pairs as in most grid biased amps that use four output tubes.
The EL84S is rated as a 12 watt tube, standard EL84 specs but in test they easily can dissipate 14 watts and hold up better than one would expect. I think these are the best current production EL84 tubes out there and rival many NOS types.
The Electro Harmonix EL84 is also out there and is a pretty nice tube. It is not as strong as the JJ but does have some cool sonic attributes. It does hold up nicely and is more reliable than the Ei. This tube has welded plates rather than crimped plates and at time you will find their match go south in some factory runs pretty fast. I think this is due to impurities in the plate welds where the heat treating of the plates was done before the plates were welded together rather than after the fact so as they heat up there are gasses released inside the tube from the impurities of the weld that were not removed in heat treating after plate welding.
GuitarZ: Best Pandemic Comment - Delivery guy shows up. As we're social distancing, I look at myself in brown loafers, black socks, gym shorts, t-shirt and say "I realize this is not my best look". His response "You can wear whatever you want to the apocalypse."
May 1, 2020 14:39:30 GMT -7
roscoenyc: read a newspaper.
May 19, 2020 17:20:32 GMT -7
roscoenyc: You know in school when they talked about "your permanent record"? Well, this is it! Learn to spell! Don't be stupid!
May 21, 2020 8:19:01 GMT -7
premiumplus (Dave): Due or do? Which or witch? Knob or nob? Their or there? Bass or base? Too much time on my hands...
May 24, 2020 6:31:30 GMT -7
roscoenyc: Ah, the incessant tire kickers. oh jeez.
May 25, 2020 6:57:46 GMT -7
GuitarZ: Needed some noise to fill a break in a tune I'm recording. It was too quiet. Just happened to have some High Quality Dr Z Ghia noise to fill the void. "Heal Your Sound with Dr Z! It's not just a guitar tone prescription!"
Jun 13, 2020 8:29:27 GMT -7
GuitarZ: Must be great to be a skunk. Eating bird food about 10' from our sun room. I'm clapping and yelling. At best, it might have given me one "yea what?" look while continuing to dine. At one point, there were two skunks and two racoons.
Jun 14, 2020 18:49:33 GMT -7
captainron (Ron): Hueter Toledo, just another business of today that doesn't care about tomorrow!
Jun 25, 2020 12:51:43 GMT -7
KeithA: Hueter Toledo....that business is gone to the dogs
Jun 26, 2020 8:22:26 GMT -7
easyed: Guitar Z, I encountered to ultimate garbage raiding combo once. We'd been having problems with the garbage cans being raided by raccoons for weeks. Late in the evening I heard rattling at the cans. I went out and found that he'd allied with a skunk. "OK"
Jun 30, 2020 11:40:27 GMT -7
GuitarZ: EasyEd - Someone at work topped us both. The inside of their car had been somewhat ransacked. They were blaming their son. They checked the video. It was a Bear! I'll stick with the racoons, skunks, foxes, and squirrels.
Jul 1, 2020 16:47:50 GMT -7
bigboki: In this age and time when everybody are struggling and especially S&Ms I am amazed to see that kind of ignorance. I am really sorry for your experience dear Dr Z but it is for the better. You don't want to do business with those kind of people anyway.
Jul 4, 2020 8:17:40 GMT -7
GuitarZ: Didn't want to restart the plumbing thread, so I figured I'd ShoutBox this. How the heck does cleaning the aerator on a faucet cause a leak to start under the faucet? Huh? Arggggh!!!!
Jul 10, 2020 7:40:17 GMT -7
The Bad Poodle Experience: well, Mike, it shouldn't have been the cause of a leak. double-check your work.
Jul 10, 2020 12:56:49 GMT -7
GuitarZ: I updated in the Plumbing thread that the Moen website says that a faulty aerator can cause a handle/base leak. Eiyy! I really don't understand how plumbing works. I was ready to double check all connections. But, the leaking stopped with cleaned Aerator.
Jul 11, 2020 18:13:56 GMT -7