JJ Electronics Slovakian Vacuum Tubes:

Inspector #20

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Anybody have experience with these??? Seem like a better buy than the China-made Groove Tubes....Thoughts????
 
I've had JJ tubes in a couple of different amps. I'm probably not the best person to ask. I can't hear a lot of difference between different brands of tubes unless they are going bad. They worked fine in the amps I had them in but so did other brands.
 
Cool...everyone loves Groove Tubes, but they are China made...so I'm looking at alternative makers.

Got tubes going out in both amps...
 
JJ tubes are ok. Their ECC83 are closest to the former Telefunken valves, soundwise. They are (at least were) using the same process and the old machines. The only tubes where actual problems have occured in the past are the JJ EL34.

Up to now i had (heater-) failures of two EHs: an ECC82 /12AU7, an ECC83/12AX7 and an EL84. None on JJs.

A few things should be noted: the pins of the JJ nine point sockets are a tiny little bit thinner than usual. So if the sockets are *really* worn out (=old) there can be contact problems.
A few years ago they changed the cathodes and reduced their emission to the minimum meeting the specs. In normal operation his cannot be noticed. But they are unusable in LoV applications, especially at 12 V (in my tests they need at least 18 V...)

BTW: their cheap ECC83 is technologically the best ECC83 on the market due to the advanced grid construction.
 
i got the JJs ECC83s, thats there 12AX7s. then there is a couple styles of the ECC83s. some have a little bigger elliment on the inside.im not sure of the proper term.i think one has a hair more gain. i mostly have just small low wattage amps ive used these in.
 
i got the JJs ECC83s, thats there 12AX7s. then there is a couple styles of the ECC83s. some have a little bigger elliment on the inside.im not sure of the proper term.i think one has a hair more gain. i mostly have just small low wattage amps ive used these in.
Apparently there are two or three basic types: the ECC83S, the ECC803 and the ECC83 MG. According to the photos shown by a german dealer. The one with the larger system - the ECC803 - is described here: https://www.tube-town.net/ttstore/Tubes/JJ-Electronic/JJ-ECC803-12AX7::3243.html

To me that reads that the cheaper tube with the smaller systems is superior except in high gain guitar amps.
 
I've had good experiences with JJ's. I have retubed several amps in the last few years with them and they have sounded good and been durable, but I will say that in at least one case, an amp that I had sounded better with Chinese preamp tubes in it. Don't know why, just did, so I ended up pulling the JJ's and putting GT12AX7C's in. So, I think some amount of experimentation is in order. Some amps are purported to sound better with Russian tubes too.
 
Thanks to all who replied. The 12ax7 in my 1997 VS265 is still original, so I think its time to replace it.

One of my DSL40C's developed that "wind blowing" or "air escaping" sound rather suddenly, so it's likely tube time.

I fed tubes to my JTM30 and JTM45 lije candy. Back then, you could buy tubes at Thrifty Drug Stores... :-)
 
When i was a kid we had a Tube tester in the local Safeway grociery store :) looked like a big Pinball machine or something.
 
Groove Tubes: Fender bought out GT about 9 years ago. Up to that time, GT sourced their tubes not only from China, but from Russia and Slovakia, too. I doubt that has changed for today's GT offerings.

Here's an old chart:
Groove Tubes Cross Reference Chart
Groove Tubes Part Number Original Part Number
GT-6L6B Sovtek 5881WXT
GT-6L6S JJ 6L6GC
GT-E34LS JJ E34L
GT-EL34R Electro-Harmonix EL34
GT-EL84R Sovtek EL84
GT-EL84S JJ EL84
GT-6V6R Electro Harmonix 6V6GT
GT-6V6S JJ 6V6S
GT-12AX7C Shuguang 12AX7-A
GT-12AX7R Sovtek 12AX7-WA
GT-12AX7R2 Sovtek 12AX7-LPS Vacuum Tube
GT-12AX7R3 Electro-Harmonix 12AX7-EH
GT-ECC83S JJ ECC83-S
GT-12AT7 Shuguang 12AT7
GT-12AY7 Electro-Harmonix 12AY7EH / 6072

http://www.thetubestore.com/Tubes/Groove-Tubes
 
Why? I am still running some amps with 50 year old tubes.

Probably because you are not recording with amps in an isloation room at nearly full volume. I run a 90 watt Celestion Creamback in the 40watt DSL40C so I can run the amp wide open without the speaker breaking up.

When we were playing lots of outdoor venues with my JTM45 Full Stack, we were replacing tubes all the time.

SRV's amp tech also stated that a key, and often overlooked component of SRV's tone, was that he (like Gary Moore) ran almost full volume.....

Watch Gary roll his volume knob on an off, before and after each riff, in an effort to control his rig at full volume...

 
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