Review Notes Tube reviews written by John Templeton.
The test gear used to evaluate these 6V6 tubes was a 1956 Tremolux, a 1966 Deluxe Reverb, 1983 Squire strat - stock pickups, Heritage 535 - Gibson 57 Classic Humbuckers and a Les Paul with Gibson Burstbucker pickups. Strings were a mix of GHS and D'Addario 10-52 gauge. No outboard effects. George L's custom cables from the guitars to the amp.
JAN Philips 6V6GT - This is a premium grade tube that was originally sold under several brand names. Construction is very robust and it had to be in order to survive the applications they were used in. Those applications usually involved plate voltages that were far beyond the design parameters of the NOS tube. They can also take a lot of physical stress.
There is nothing lacking in the tone department, having a nicely balanced response across the frequency spectrum. Biasing is very forgiving allowing you to set them to run cool for extended life or toasty for lots of breakup at lower volumes. Abuse does not come without a price. If you run these tubes real hard and biased hot they can become mechanically noisy and rattle after a few months. If you have any of the smaller Fender tweed amps, silver and blackface Champs, Princeton's and Deluxe Reverbs, this can be considered a genuine OEM replacement part. Fender used them extensively from the 50's through to the early 80's.
For vintage tone and of course the "vibe", this is what you need. Back to top
Electro Harmonix 6V6GT - When EH brought out this 6V6, guitar players everywhere gave a huge sigh of relief. Finally someone was producing an affordable alternative to NOS that kicked ass in the tone department and was able to survive the 6V6 torture test - the Deluxe Reverb. EH got it right.
The EH 6V6 can take high plate voltages while producing sweet, singing sustain or all out crunch. Physically it bares a close resemblance to the old RCA 6V6 with a rounded, oval plate structure, straight glass and rugged support spacers. This tube is OEM in most currently produced amplifiers that require a 6V6. This is the current industry standard with a well earned reputation for great tone and long life at a very affordable price. There's a new player in town that may give the EH a run for its money, check out the review on the JJ 6V6. Back to top
Genalex / Gold Lion CV511/6V6GT reissue - The Gold Lion 6V6 is the top of the line in current production 6V6 power tubes. To go on about the subtle tone variation would frankly be a waste of time. They have the classic 6V6 sound. Plenty of smooth creamy overdrive. You won’t get better tone and reliability from anything else on the market. If you want even more then look for NOS tubes like Brimar U.K., Philips, or RCA. To test the initial reliability I installed a set in a 1956 Bassman. The dual 5U4GB rectifiers provide a rock solid 440 volts on the plates. The only modifications done to the amp were upgraded screen resistors (5w 1K) and a variable bias control. I’ve done this with NOS tubes and the JJ 6V6 (an indestructible tube) but never with a Russian or Chinese product. Happily there were no issues, or smoke, only great tone. DO NOT try this at home, it was only a test to see if they would burn out on startup. Currently there is no long term performance data on life expectancy or road worthiness but given the rugged construction I expect them to be equal or superior to anything else in the current market offerings. Back to top
JJ 6V6S - In addition to JJ’s other robust line of power tubes, a 6V6 is being produced that is extremely good. There is no longer a need to search out expensive NOS that have been picked over for 20 years. While there is a market for the NOS product, you are no longer required to buy NOS in order to get really great results.
For about 6 months I have been torture testing the JJ 6V6 in guitar amplifiers. That not only includes using them, but putting them in real life working situations. They have been subject to rough handling, over biasing and under biasing in amps with plate voltages ranging from 380 – 475 VDC. The tubes would not die and the matching on them drifted less than 2 ma over the life of the test. That’s about six months of continuous use and abuse.
How do they sound? That’s probably the most important question and a very easy one to answer. These tubes sound great, period. They do clean with smooth clear high end. On the other end of the spectrum big fat bass notes that are well defined having a piano like quality are produced. Crank up the gain and you will get everything from a nice crunch to all out screaming distortion. And not just mush, but a very controllable, musical distortion. A well tuned amp running the JJ 6V6 and getting a good strong signal from your guitar may make you want to cash in your old TS808. One rig that was used as a tester consisted of a ‘66 Deluxe Reverb fitted with a Celestion Vintage 30. The JJ’s were put in with a plate voltage of 440 volts and biased at about 80% of their rated output. This would kill many tubes (and had in the past). A current production Les Paul Standard was plugged in and the resulting sound could only be described as “crazy”. Just about any genre of music from blues, jazz to classic rock was obtained.
If you are a guitar picker with a love for tone you owe it to yourself to try a set of these outstanding tubes. Back to top
Mullard 6V6GT - This is a very nice 6V6 vacuum tube that is built quite ruggedly. In addition to the normal internal supports there are support rods running from the top mica to the bottom mica. This must help to limit movement of any of the internal elements. Tung-Sol has added these rods to their 6V6-GT tubes since the original release which had none. While the Tungsol has a single bent cooling fin attached to both copper support rods below the getter, the Mullard has two individual cooling fins.
The sound is exactly what you expect with any good 6V6. They have sparkle and chime at lower volumes, and the notes thicken and bloom as you increase the volume. When wound up these little tubes can yield a wild amount of crunch to a fluid overdrive. These would be great in single end amps and will make your Deluxe Reverb bark.
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TAD 6V6GT-STR - The EH 6V6 is designed and built much like an RCA and captures the classic sound. The new TAD does this and more. It has all the classic tone you want, plenty of gain and very little noise at all. It will handle the abuse that currently can only be handled by the JJ 6V6-S tube. Traditionalists don’t seem to trust the JJ because of its unique construction and think of it as something between a 6V6 and 6L6. They have been my favorites because you can punish them and they take it. With the TAD there is now another tube that gives me that same feeling of security.
The bottle is made from very thick glass and my sample of four were consistently straight and internally well aligned. I have no worries at running them at 450 volts and above average current. The plate construction is more conventional than a JJ but TAD has added cooling fins to both halves of the plate structure. This helps get rid of the excess heat when you run them outside of the standard 6V6 envelope.
If you are looking for something more traditional than the JJ 6V6S tube but more rugged than the EH 6V6, the TAD 6V6GT-STR tube should hit the sweet spot.
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Tung-Sol 6V6GT - The Tung-Sol 6V6-GT is an outstanding tube and I feel it delivers a much smoother overdrive that you could describe as creamy instead of crunchy. The tone is better that almost anything I've heard. The only comparable is the 7408 from RCA and that an industrial grade worth a fortune. The sound is better defined than the Electro Harmonix with less compression than EH or JJ. The trade off is that they are not as loud as the JJ, they have less "in your face" midrange but that's about it. I ran a set in a slightly modified ‘59 Bassman (450 plate volts biased at about 9 watts static dissipation). No problems at all and the blues tone was incredible, much smoother than NOS or JJ with a fluid musical distortion and moderate compression. By comparison, the JJ was louder, compressed hard and had a crunchy rock sound. No microphonics with the Tung-Sol and a very low noise floor. In a tweed amp like a Deluxe or Tremolux that is made for a 6V6, the blues players may pee their pants. Although they are well made (different than the EH), it is possible that you would want something more like the JJ when playing in bars just because their hard midrange cuts a bit better. All of the Tung-Sol brand tubes seem to be worth the money. The JJ and the Tung-Sol are the only 6V6 tubes I will use in my amps or sell to customers from now on. For a vintage purest I would go Tung Sol all the way since they sound great and look like the real deal.